JP5352777B2 - Quartz device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a crystal device by performing microfabrication of a crystal substrate by dry etching. <P>SOLUTION: An adhesive film 21 is vacuum-pasted by a vacuum-paste device 3 to a supporting substrate 11 cleaned by a cleaning device 2. A crystal substrate 9 which has formed mask layers 13a, 13b is vacuum-pasted on the supporting substrate 11 via the adhesive film 21 by a vacuum pasting device 4. Electrostatic attraction is performed to the supporting substrate 11, heat transmission gas is supplied between the supporting substrate 11 and a substrate mounting surface 41a, and dry etching of a crystal substrate 9 is performed. Etching is performed to the depth where a part of an outer shape cross section of a crystal device remains by dry etching on the surface 9a. After the dry etching of the surface 9a, an adhesive layer is removed by wet etching and the crystal substrate 9 is peeled off the supporting substrate 11. Etching is performed by the dry etching on a reverse surface 9b to the depth where a remaining part of the outer shape cross section of the crystal device is removed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing a crystal device such as a crystal resonator element.

  In the manufacture of a crystal device such as a crystal resonator element, wet etching is employed as a method for processing a crystal substrate. However, the processing width that can be realized by wet etching of the quartz substrate is about 100 to 80 μm, and miniaturization has a limit. Further, in wet etching, the quartz substrate is etched along the crystal orientation, which becomes a processing restriction.

  In order to solve the limit of miniaturization and processing restrictions unavoidable in wet etching, it has been proposed to process a quartz crystal substrate by dry etching. For example, Patent Documents 1 and 2 disclose a method of manufacturing a quartz crystal resonator element from a quartz substrate by using dry etching and wet etching together. Patent Document 3 discloses a method of manufacturing a crystal vibrating piece from a crystal substrate only by dry etching.

  However, a dry etching method that can be practically used in consideration of the characteristics of a quartz substrate, which is a hard and brittle material having high hardness, including those disclosed in Patent Documents 1 to 3, has not been proposed. That is, it is possible to experimentally finely process a crystal piece or the like by a general dry etching method. For example, the diameter or side is about 2 to 3 inches, and the thickness is about 100 to 200 μm or less. There has not yet been provided a practical dry etching method that is very thin and brittle and that can realize fine processing on a quartz substrate that is easily warped or cracked due to heat.

JP 2007-13383 A JP 2007-259036 A JP 2007-166242 A

  An object of the present invention is to provide a practically practical manufacturing method for manufacturing a crystal device by finely processing a quartz substrate, which is a brittle material having high hardness and brittleness, by dry etching.

The present invention includes a vacuum vessel to which an etching gas is supplied, a plasma generation source that generates plasma by ionizing the etching gas in the vacuum vessel, and a dielectric that is disposed on the bottom side of the vacuum vessel. A substrate mounting portion, an electrostatic adsorption electrode built in the substrate mounting portion, and a heat transfer gas supply mechanism for supplying heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting portion. And a quartz substrate having a mask layer corresponding to the shape of the quartz crystal device formed on the first and second surfaces facing each other, and a support having a larger area than the quartz substrate. A substrate is prepared, an adhesive layer is formed on a first surface of the support substrate facing each other, and an adhesive layer is formed on the first surface, and the second surface of the quartz substrate is placed on the second surface via the adhesive layer. Bonding to the first surface of the support substrate The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a direct current is applied to the electrostatic chucking electrode. A voltage is applied to electrostatically attract the support substrate to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. While supplying, plasma is generated by the plasma generation source to etch the first surface of the crystal substrate to a depth where a part of the outer cross section of the crystal device remains, and the etching of the first surface of the crystal substrate is completed. Later, the support substrate to which the crystal substrate is bonded is carried out of the vacuum container, the adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the crystal substrate is peeled off from the support substrate. The support group Forming the pressure-sensitive adhesive layer again on the first surface of the substrate, bonding the first surface of the crystal substrate that has been etched through the pressure-sensitive adhesive layer to the first surface of the support substrate, The support substrate bonded with the substrate is carried into a vacuum vessel of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a DC voltage is applied to the electrostatic chucking electrode. Then, the support substrate is electrostatically attracted to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. Etching the second surface of the quartz crystal substrate by etching the second surface of the quartz crystal substrate to a depth at which the remaining part of the outer cross section of the quartz crystal device is removed by generating plasma from the plasma generation source. After completion, the support to which the quartz substrate is bonded is attached. The holding substrate is taken out of the vacuum container, the pressure-sensitive adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the second surface of the crystal substrate is bonded to the support substrate through the pressure-sensitive adhesive layer. In this case, there is provided a method for manufacturing a crystal device, wherein at least the mask layer formed on the second surface of the crystal substrate is pushed into the pressure-sensitive adhesive layer to such a depth that the mask layer is buried in the pressure-sensitive adhesive layer .

  In a state where the quartz substrate is bonded to the support substrate via the adhesive layer, handling such as loading / unloading of the dry etching apparatus into / from a vacuum container, mounting on the substrate mounting portion of the dry etching apparatus, and the like is performed. Therefore, it is possible to reliably prevent the quartz substrate, which is a hard and brittle material, from being damaged by an external force that acts during handling such as loading and unloading. Even when the quartz substrate is very thin with a thickness of, for example, 200 μm or less, particularly about 100 μm or less, it is possible to carry it in and out of the vacuum container without damaging the quartz substrate.

  Since the quartz substrate is bonded to the support substrate via the adhesive layer, the mutual adhesion between the support substrate, the adhesive layer, and the quartz substrate is high. Further, the support substrate is held with high adhesion to the substrate mounting surface by electrostatic adsorption. Therefore, the heat conductivity between the support substrate and the substrate mounting surface via the heat transfer gas and the heat conductivity between the support substrate and the quartz substrate via the adhesive layer are both good. As a result, the quartz substrate can be cooled with high cooling efficiency, and the temperature of the quartz substrate can be controlled with high accuracy. By cooling the quartz substrate with high efficiency and high accuracy, the quartz substrate is warped, peeled, cracked, or other damage caused by heat, or the quartz substrate itself is heated to a high temperature (for example, 400 to 500 ° C. or higher). Alteration can be prevented.

  By embedding the second surface of the quartz substrate to a sufficient depth in the adhesive layer, the plasma wraps around the boundary between the second surface of the quartz substrate and the adhesive layer, and the adhesive of the quartz substrate resulting therefrom Peeling from the layer can be prevented. That is, during etching of the first surface of the quartz substrate, the quartz substrate is held in close contact with the support substrate via the adhesive layer.

  Preferably, the depth at which the second surface of the quartz substrate is pushed into the pressure-sensitive adhesive layer is such that the height from the support substrate to the surface of the pressure-sensitive adhesive layer at the end of etching of the first surface of the quartz substrate. The height is set according to the selection ratio between the quartz substrate and the adhesive layer so as to be higher than the height from the support substrate to the second surface of the quartz substrate. Thereby, it is possible to more reliably prevent the plasma from entering the boundary between the second surface of the quartz substrate and the adhesive layer until the etching of the first surface of the quartz substrate is completed.

In addition, the present invention provides a vacuum vessel to which an etching gas is supplied, a plasma generation source that generates plasma by ionizing the etching gas in the vacuum vessel, and a dielectric that is disposed on the bottom side of the vacuum vessel. Heat transfer gas supply for supplying heat transfer gas to the substrate mounting surface disposed on the substrate mounting portion, the electrostatic chucking electrode built in the substrate mounting portion, and the substrate mounting surface which is the upper end surface of the substrate mounting portion A dry etching apparatus having a mechanism, and preparing a quartz substrate in which a mask layer corresponding to the shape of the quartz crystal device is formed on each of the first and second surfaces facing each other, and having a larger area than the quartz substrate. A support substrate is prepared, an adhesive layer is formed on the first surface of the support substrate facing each other, and an adhesive layer is formed on the first surface, and the second surface of the quartz substrate is interposed through the adhesive layer. Affixed to the first surface of the support substrate The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and the electrostatic chucking electrode A DC voltage is applied to the support substrate to electrostatically attract the support substrate to the substrate mounting surface, and the heat transfer gas supply mechanism causes the heat transfer between the substrate mounting surface and the second surface of the support substrate. While supplying the gas, plasma is generated by the plasma generation source to etch the first surface of the crystal substrate to a depth at which a part of the outer cross-section of the crystal device remains, and the first surface of the crystal substrate is etched. After the etching is completed, the support substrate to which the crystal substrate is bonded is taken out of the vacuum container, the pressure-sensitive adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the crystal substrate is peeled off from the support substrate. After said Forming the pressure-sensitive adhesive layer again on the first surface of the holding substrate, and bonding the first surface of the crystal substrate that has been etched through the pressure-sensitive adhesive layer to the first surface of the support substrate; The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a DC voltage is applied to the electrostatic chucking electrode. And the support substrate is electrostatically adsorbed on the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. However, plasma is generated by the plasma generation source to etch the second surface of the quartz substrate to a depth at which the remaining part of the outer cross section of the quartz device is removed, and the second surface of the quartz substrate After completion of etching, the quartz substrate was bonded The support substrate is unloaded from the vacuum container, the pressure-sensitive adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the first surface of the crystal substrate is attached to the support substrate via the pressure-sensitive adhesive layer. Provided is a method for manufacturing a crystal device, wherein at the time of bonding, the crystal substrate is pushed into the pressure-sensitive adhesive layer to such a depth that at least a processing step of the first surface of the crystal substrate caused by etching is embedded in the pressure-sensitive adhesive layer. .

  By burying the first surface of the quartz substrate in which a processing step is generated by etching to a sufficient depth in the adhesive layer, the plasma wraps around the boundary between the first surface of the quartz substrate and the adhesive layer; The peeling from the adhesive layer of the quartz substrate resulting from it can be prevented. Therefore, during etching of the second surface of the quartz substrate, the quartz substrate is more securely held in a state of being in close contact with the support substrate via the adhesive layer. In addition, since the adhesion area between the first surface of the quartz substrate and the adhesive layer increases, the thermal conductivity between the support substrate and the quartz substrate via the adhesive layer becomes better, and the quartz substrate The cooling efficiency of the quartz substrate during etching of the second surface can be improved. In particular, since the heat conduction from the quartz substrate to the support substrate is proportional to the square of the shortest distance between the two, when the machining depth of the first surface of the quartz substrate is large (for example, the machining depth is more than twice the etching width) In this case, the thermal conductivity between the quartz substrate and the support substrate is lowered, but the first surface of the quartz substrate in which the processing step is generated is embedded to a sufficient depth in the adhesive layer. Thus, this decrease in thermal conductivity can be suppressed.

  Preferably, the depth at which the first surface of the quartz substrate is pushed into the pressure-sensitive adhesive layer is such that the height from the support substrate to the surface of the pressure-sensitive adhesive layer at the end of etching of the second surface of the quartz substrate. The height is set according to the selection ratio between the quartz substrate and the pressure-sensitive adhesive layer so as to be higher than the height from the support substrate to the first surface of the quartz substrate. Accordingly, it is possible to reliably prevent the plasma from entering the boundary between the first surface of the quartz substrate and the adhesive layer until the etching of the second surface of the quartz substrate is completed.

The present invention includes a vacuum vessel to which an etching gas is supplied, a plasma generation source that generates plasma by ionizing the etching gas in the vacuum vessel, and a dielectric that is disposed on the bottom side of the vacuum vessel. A substrate mounting portion, an electrostatic adsorption electrode built in the substrate mounting portion, and a heat transfer gas supply mechanism for supplying heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting portion. And a quartz substrate having a mask layer corresponding to the shape of the quartz crystal device formed on the first and second surfaces facing each other, and a support having a larger area than the quartz substrate. A substrate is prepared, an adhesive layer is formed on a first surface of the support substrate facing each other, and an adhesive layer is formed on the first surface, and the second surface of the quartz substrate is placed on the second surface via the adhesive layer. Bonding to the first surface of the support substrate The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a direct current is applied to the electrostatic chucking electrode. A voltage is applied to electrostatically attract the support substrate to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. While supplying, plasma is generated by the plasma generation source to etch the first surface of the crystal substrate to a depth where a part of the outer cross section of the crystal device remains, and the etching of the first surface of the crystal substrate is completed. Later, the support substrate to which the crystal substrate is bonded is carried out of the vacuum container, the adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the crystal substrate is peeled off from the support substrate. The support group Forming the pressure-sensitive adhesive layer again on the first surface of the substrate, bonding the first surface of the crystal substrate that has been etched through the pressure-sensitive adhesive layer to the first surface of the support substrate, The support substrate bonded with the substrate is carried into a vacuum vessel of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a DC voltage is applied to the electrostatic chucking electrode. Then, the support substrate is electrostatically attracted to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. Etching the second surface of the quartz crystal substrate by etching the second surface of the quartz crystal substrate to a depth at which the remaining part of the outer cross section of the quartz crystal device is removed by generating plasma from the plasma generation source. After completion, the support to which the quartz substrate is bonded is attached. A holding substrate is unloaded from the vacuum container, the pressure-sensitive adhesive layer is removed, the quartz substrate is peeled off from the supporting substrate, and the supporting substrate has a conductive portion on at least the second surface. Provide a method. The support substrate may be formed by forming a conductive film as a conductive portion on a dielectric such as sapphire or quartz, or the support substrate may be made of a conductive material such as Si.

The present invention includes a vacuum vessel to which an etching gas is supplied, a plasma generation source that generates plasma by ionizing the etching gas in the vacuum vessel, and a dielectric that is disposed on the bottom side of the vacuum vessel. A substrate mounting portion, an electrostatic adsorption electrode built in the substrate mounting portion, and a heat transfer gas supply mechanism for supplying heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting portion. And a quartz substrate having a mask layer corresponding to the shape of the quartz crystal device formed on the first and second surfaces facing each other, and a support having a larger area than the quartz substrate. A substrate is prepared, an adhesive layer is formed on a first surface of the support substrate facing each other, and an adhesive layer is formed on the first surface, and the second surface of the quartz substrate is placed on the second surface via the adhesive layer. Bonding to the first surface of the support substrate The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a direct current is applied to the electrostatic chucking electrode. A voltage is applied to electrostatically attract the support substrate to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. While supplying, plasma is generated by the plasma generation source to etch the first surface of the crystal substrate to a depth where a part of the outer cross section of the crystal device remains, and the etching of the first surface of the crystal substrate is completed. Later, the support substrate to which the crystal substrate is bonded is carried out of the vacuum container, the adhesive layer is removed, the crystal substrate is peeled off from the support substrate, and the crystal substrate is peeled off from the support substrate. The support group Forming the pressure-sensitive adhesive layer again on the first surface of the substrate, bonding the first surface of the crystal substrate that has been etched through the pressure-sensitive adhesive layer to the first surface of the support substrate, The support substrate bonded with the substrate is carried into a vacuum vessel of the dry etching apparatus, the second surface of the support substrate is mounted on the substrate mounting surface, and a DC voltage is applied to the electrostatic chucking electrode. Then, the support substrate is electrostatically attracted to the substrate mounting surface, and the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism. Etching the second surface of the quartz crystal substrate by etching the second surface of the quartz crystal substrate to a depth at which the remaining part of the outer cross section of the quartz crystal device is removed by generating plasma from the plasma generation source. After completion, the support to which the quartz substrate is bonded is attached. The holding substrate is carried out of the vacuum container, the pressure-sensitive adhesive layer is removed, the quartz crystal substrate is peeled off from the support substrate, the pressure-sensitive adhesive layer is formed on the entire surface of the support substrate, and the pressure-sensitive adhesive layer is a polyimide-based material Provided is a method for manufacturing a crystal device, which comprises an adhesive and the chemical used for the wet etching is an organic solvent.

  Since the entire surface of the support substrate is covered with the adhesive layer, it is possible to prevent the support substrate from being etched during dry etching of the crystal substrate. As a result, contamination due to the material etched away from the support substrate can be prevented, and the service life of the support substrate can be extended.

  By removing the pressure-sensitive adhesive layer from the support substrate by wet etching, mechanical stress acting on the quartz substrate that causes damage such as cracking can be minimized when the quartz substrate is peeled from the support substrate.

  Preferably, the pressure-sensitive adhesive layer is removed by an ashing process before the pressure-sensitive adhesive layer is removed and the quartz substrate is separated from the support substrate. Specifically, the height from the support substrate to the surface of the pressure-sensitive adhesive layer is made lower than the height from the support substrate to the surface of the quartz substrate on the support substrate side by the ashing process. When the pressure-sensitive adhesive layer is removed to this height, the chemical solution can easily enter the boundary between the crystal substrate and the pressure-sensitive adhesive layer (the bonding surface of the crystal substrate to the pressure-sensitive adhesive layer) from the side wall of the crystal substrate, and the crystal substrate is peeled off from the support substrate. The time required to do this can be shortened.

  Preferably, the support substrate includes a groove or a through hole for introducing a chemical used for the wet etching into the pressure-sensitive adhesive layer. Providing such grooves and through holes also facilitates the entry of the chemical into the boundary between the quartz substrate and the adhesive layer (the bonding surface of the quartz substrate to the adhesive layer), in order to peel the substrate from the support substrate. The time required can be shortened.

  By performing cooling by such a cooling mechanism, the quartz substrate during dry etching can be cooled with higher efficiency and higher accuracy.

  According to the method for manufacturing a crystal device of the present invention, the crystal substrate is bonded to the support substrate through the adhesive layer, so that the crystal substrate is damaged by an external force that is applied during handling such as loading / unloading of the dry etching apparatus into / from the vacuum container. Can be reliably prevented. In addition, the support substrate on which the quartz substrate is bonded through the adhesive layer is held with high adhesion to the substrate mounting surface by electrostatic adsorption, and heat transfer gas is supplied between the support substrate and the substrate mounting surface. Since the dry etching is performed in a state, the quartz substrate can be cooled with high efficiency and high accuracy, and the quartz substrate can be prevented from being warped, peeled off, cracked, or the like due to heat, or the quartz itself is altered. Therefore, by the manufacturing method of the present invention, it is possible to realize fine processing by dry etching on a quartz substrate which is a practically practical hard and brittle material.

  In particular, the formation of the pressure-sensitive adhesive layer on the support substrate is performed by sticking in a vacuum atmosphere, or the quartz substrate is bonded to the support substrate via the pressure-sensitive adhesive layer in a vacuum atmosphere, thereby interposing bubbles. Since the quartz substrate can be bonded to the support substrate via the pressure-sensitive adhesive layer in a state of having a high degree of adhesion, the quartz substrate can be cooled with higher efficiency and higher accuracy during dry etching.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since quartz is high in hardness and brittle, the quartz substrate has characteristics different from those of general processing objects such as a semiconductor substrate in performing fine processing by dry etching. Specifically, a quartz crystal substrate used for manufacturing a quartz crystal device such as a quartz crystal vibrating piece is very thin and brittle with a diameter or a side of about 2 to 3 inches and a thickness of about 100 to 200 μm or less. Therefore, handling such as carrying in and out of the vacuum chamber of the dry etching apparatus is difficult. In addition, since the quartz substrate is very hard and has a slow etching rate, during dry etching, the quartz substrate is exposed to heat from plasma for a long time and becomes high temperature. As described above, a very thin and brittle quartz substrate having a thickness of about 100 to 200 μm is liable to be warped by heat and cracks caused by it. In addition, the crystal itself is altered by the high temperature during dry etching. Specifically, the crystal itself is altered at a high temperature of about 400 to 500 ° C. or more. Therefore, sufficient measures against heat are necessary in dry etching of a quartz substrate. In consideration of the above points, the embodiment of the present invention described below practically implements fine processing by dry etching of a quartz substrate.

(First embodiment)
Referring to FIG. 1, a crystal device manufacturing apparatus 1 in this embodiment includes a cleaning apparatus 2, a vacuum bonding apparatus 3 (shown schematically in FIG. 2), a vacuum bonding apparatus 4, and a dry etching apparatus 6 (details are shown in FIG. 3). And a wet etching apparatus 7. This crystal device manufacturing apparatus 1 uses a tuning-fork type crystal vibrating piece 8 shown in FIGS. 4A and 4B, which is an example of a crystal device, on both surfaces, that is, the surface (first surface) of the crystal substrate 9 shown in FIGS. ) Manufacturing is performed by performing dry etching on both 9a and the back surface (second surface) 9b. Further, in this crystal device manufacturing apparatus 1, a support substrate 11 shown in FIG. 5 is used in order to facilitate handling of the crystal substrate 9. In FIG. 1, a solid line arrow indicates a path between the crystal substrate 9 and the support substrate 11 in dry etching of the surface 9a of the crystal substrate 9, and a dotted line arrow indicates a path between the crystal substrate 9 and the support substrate 11 in dry etching on the back surface 9b. .

  4A and 4B, the quartz crystal vibrating piece 8 has a shape in which a pair of arms 8b and 8c having a rectangular cross section parallel to each other extend from one side of a flat rectangular parallelepiped base 8a. Grooves 8d and 8e having a rectangular bottomed cross-sectional shape are provided on both surfaces (upper and lower surfaces in FIGS. 4A and 4B) of the individual arm portions 8b and 8c. Moreover, there are metal layers 12a and 12b on both surfaces of the base portion 8a and the arm portions 8b and 8c. These metal layers 12a and 12b are mask layers (metal masks) 13a and 13b for dry etching to be described later. The metal layers 12a and 12b may be used as an electrode for vibrating the crystal vibrating piece 8, or may be removed in a later process to form another electrode on the crystal vibrating piece 8.

  Although the dimension of the crystal vibrating piece 8 is not specifically limited, For example, it sets as follows. The thickness T1 (excluding the metal layers 12a and 12b) of the base portion 8a and the arm portions 8b and 8c is about 100 μm. The width W1 of the base 8a is about 200 to 500 μm, and the width W2 of the arms 8b and 8c is about 60 to 120 μm. The grooves 8d and 8e have a depth D1 of about 40 μm and a width W3 of about 20 to 30 μm. The thickness T2 of the metal layers 12a and 12b is about 3 to 5 μm.

  Referring to FIGS. 5, 6, and 10, the quartz crystal substrate 9 has a thin disk shape with a thickness T′1 of about 100 μm and a diameter of about 2 to 3 inches, and has an orientation flat 9 c. On the front surface 9a and the back surface 9b of the quartz substrate 9, mask layers 13a and 13b having the same shape are patterned. In the present embodiment, the mask layers 13a and 13b are made of a metal such as Ni or Cr and are formed as desired by photolithography. The thickness T′2 of the mask layers 13a and 13b is about 3 to 5 μm. However, the material and thickness of the mask layers 13a and 13b are not limited to this. The metal mask layers 13a and 13b are formed by sputtering, for example.

  The etching selectivity of the resist mask is about 1 to 3 under the etching conditions of quartz (crystal substrate 9) to be described later in detail. When the processing depth is about several tens to several hundreds μm as in this embodiment, the resist If a mask is used, its thickness needs to be several tens of μm. This thick resist mask of several tens of micrometers has a large dimensional variation in consideration of the performance and cost of the exposure apparatus. On the other hand, the etching selectivity of a metal mask such as Ni or Cr under quartz etching conditions is about 20 to 40. Therefore, when the processing depth is about several tens to several hundreds of μm, the thickness of the metal mask is 3 to 3. It may be about 5 μm, and can be formed with high accuracy while suppressing variation in dimensions. Therefore, in this embodiment, mask layers 13a and 13b made of metal such as Ni and Cr are used instead of a resist mask. However, since the metal mask layers 13a and 13b are heated during the dry etching of the quartz substrate 9 and become high temperature, and the mask layers 13a and 13b are shaved, the thickness of the mask layers 13a and 13b also changes, so that internal stress occurs. This internal stress causes warpage of the quartz substrate 9 on which the mask layers 13a and 13b are formed. That is, when the mask layers 13a and 13b made of metal are used, the quartz substrate 9 is easily warped or cracked due to heat during dry etching as compared with the case where a resist mask is used. In this embodiment, as will be described in detail later, the quartz substrate 9 on which the mask layers 13a and 13b are formed with high efficiency and high accuracy can be cooled and maintained at a relatively low temperature during dry etching. The internal stress generated in 13b is reduced or alleviated to prevent warping of the quartz substrate 9 due to heat during dry etching and damages such as cracks resulting therefrom.

  Further, in this embodiment, the mask layers 13a and 13b are formed on both the front surface 9a and the back surface 9b of the quartz substrate 9, so that the mask layer is formed only on one of the front surface 9a and the back surface 9b. Thus, the internal stress of the mask layers 13a and 13b, which has become a high temperature during dry etching, acts equally on the front surface 9a and the back surface 9b of the quartz substrate 9. In this respect as well, damage such as warpage of the quartz substrate 9 due to heat during dry etching and cracks caused by the warpage can be prevented.

  Referring to FIG. 6, each mask layer 13 a, 13 b includes an annular frame portion 14 formed near the periphery of the quartz substrate 9 and two linear frame portions 15 a, 15 b arranged so as to be orthogonal to each other. Prepare. In addition, a large number of device forming portions 16 for forming the crystal vibrating piece 8 are provided in each of four regions in the annular frame portion 14 partitioned by the straight frame portions 15a and 15b. Specifically, the device forming portion 16 has a contour corresponding to the outer shape of the crystal vibrating piece 8 to be processed, and has an opening 17 in a portion corresponding to the grooves 8d and 8e. A large number of device forming portions 16 are arranged on both sides of the branch frame portion 18, both ends of which are continuous with the straight frame portion 15 a and the annular frame portion 14. By subjecting the front surface 9a and the back surface 9b of the quartz substrate 9 to dry etching, the exposed portion of the quartz crystal is removed without being covered with the mask layers 13a and 13b. Grooves 8d and 8e are formed. Thereafter, by separating the device forming portion 16 from the branch frame portion 18, the individual crystal vibrating pieces 8 shown in FIGS. 4A and 4B are obtained. In the following description, unless specifically mentioned, the mask layers 13a and 13b simply refer to the device forming portion 16. The shapes of the mask layers 13a and 13b are not limited to this example, and can be arbitrarily set according to the shape and number of crystal devices to be processed.

  Referring to FIGS. 5 and 9, the support substrate 11 has a thin disk shape having a sufficiently larger area than the quartz substrate 9, and is provided with a notch 11c. In this embodiment, the area of the support substrate 11 is such that the five crystal substrates 9 are sufficiently spaced apart from each other, and any crystal substrate 9 is sufficiently spaced from the outer peripheral edge of the support substrate 11. It is set to 200 to 340 mm so that it can be placed in a state in which it is in contact.

  In the present embodiment, the support substrate 11 is made of glass, and the conductive film 19 is formed on the lower surface (second surface) 11b. However, materials such as sapphire and quartz can be used instead of glass. Further, the support substrate 11 may be formed of Si. Since Si itself has conductivity, unlike the case of using a dielectric such as glass, sapphire, or quartz, it is not necessary to provide the conductive film 19 on the lower surface 11b. The functions required for the support substrate 11 are that it has sufficient strength, good thermal conductivity, can be electrostatically adsorbed by an electrostatic adsorption electrode 47 described later, and is not easily etched by plasma. In addition, when the quartz substrate 9 is peeled off from the support substrate 11 by wet etching, it may not be shaved. As long as these functions are obtained, the material, structure, dimensions, and the like of the support substrate 11 are not particularly limited. For example, in the present embodiment, the thickness T ″ of the support substrate 11 is about 600 to 800 μm, but the thickness T ″ is not particularly limited as long as sufficient strength can be secured.

  The support substrate 11 is formed with a large number of through holes 11d penetrating from the upper surface 11a to the lower surface 11b in the thickness direction in five regions (see FIG. 5) where the crystal substrate 9 is bonded via the adhesive film 21. . These through holes 11d have a function of introducing a chemical used for wet etching into the adhesive film 21 when the quartz substrate 9 is peeled from the support substrate 11 by wet etching, as will be described in detail later. The through hole 11d in the present embodiment has a circular cross-sectional shape with a diameter of about 300 to 500 μm. However, as long as necessary functions are exhibited, the number, distribution, cross-sectional shape, dimensions, and the like of the through holes 11d can be set as appropriate.

  Although details will be described later, in order to facilitate understanding of the relationship between the support substrate 11 and the quartz substrate 9, an outline of the steps executed by the quartz device manufacturing apparatus 1 in FIG. 1 will be described with reference to FIGS. 7A to 7D. To do. First, as shown in FIG. 7A, the adhesive film 21 is attached to the upper surface (first surface) 11a of the cleaned support substrate 11. Next, as shown in FIGS. 7B and 7C, the five quartz crystal substrates 9 are bonded to the support substrate 11 via the adhesive film 21. After performing dry etching in this state, as shown in FIG. 7D, the pressure-sensitive adhesive film 21 is removed by wet etching, and the five crystal substrates 9 are peeled from the support substrate 11. Thereafter, the adhesive film 21 is again attached to the upper surface 11a of the cleaned support substrate 11, and the quartz substrate 9 that is reversed upside down is attached. Then, after dry etching is performed again, the pressure-sensitive adhesive film 21 is removed by wet etching, and the five crystal substrates 9 are peeled off from the support substrate 11.

  Referring to FIG. 2, the vacuum bonding apparatus 3 performs the bonding of the adhesive film 21 to the upper surface 11 a of the support substrate 11 in the vacuum atmosphere chamber 22. The pressure-sensitive adhesive film 21 is supplied with cover films 23a and 23b provided on both sides. A supply roll 24 around which a pressure-sensitive adhesive film 21 with cover films 23a and 23b is wound is accommodated in the chamber 22 of the vacuum applicator 3. One cover film 23 a (the lower side in the figure) is peeled off from the pressure-sensitive adhesive film 21 unwound from the supply roll 24 by the peeling roll 26. The pressure-sensitive adhesive film 21 exposed by peeling off the cover film 23a is attached to the upper surface 11a of the support substrate 11, and the pressure-sensitive adhesive film 21 and the other cover film 23b are cut along the outer contour of the support substrate 11 by a cutter (not shown). The Thereafter, the other cover tape 23 b is peeled off by the peeling tape 27. The pressure-sensitive adhesive film 21 is attached to the entire surface of the support substrate 11. In other words, after the adhesive film 21 is attached, the upper surface 11a of the support substrate 11 is covered with the adhesive film 21 and is not exposed.

  In the present embodiment, the pressure-sensitive adhesive film 21 is made of a polyimide-based pressure-sensitive adhesive having a constant thickness, and the cover films 23a and 23b are made of polyethylene terephthalate (PET). Moreover, the thickness of the adhesive film 21 is about 40 μm, and the thickness of the cover films 23 a and 23 b is about 70 μm. The functions required of the adhesive film 21 include sufficient adhesive strength, high heat resistance, almost no outgas even under reduced pressure and high temperature (for example, 5 ppm or less), and can be easily removed by wet etching. is there. As long as these functions are satisfied, the type and thickness of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive film 21 are not particularly limited.

  Referring to FIG. 3, the dry etching apparatus 6 includes a chamber (vacuum container) 28 that constitutes a processing chamber that performs plasma processing on the quartz substrate 9. The upper end opening of the chamber 28 is closed in a sealed state by a top plate 29 made of a dielectric material such as quartz. An ICP (inductively coupled plasma) coil 30 as a plasma generation source is disposed on the top plate 29. A high frequency power supply 32 is electrically connected to the ICP coil 30 via a matching circuit 31. A substrate susceptor 33 having a function as a lower electrode to which a bias voltage is applied and a function as a substrate holding table is disposed on the bottom side in the chamber 28 facing the top plate 29. The chamber 28 is provided with a loading / unloading gate 34 that can be opened and closed. An etching gas supply source 37 is connected to an etching gas supply port 36 provided in the chamber 28. The etching gas supply source 37 includes an MFC (mass flow controller) and the like, and can supply the etching gas from the etching gas supply port 36 at a desired mixing ratio and flow rate. Further, a vacuum exhaust device 39 including a vacuum pump or the like is connected to an exhaust port 38 provided in the chamber 28.

  The substrate susceptor 33 is made of a substrate mounting plate (substrate mounting portion) 41 made of a dielectric material such as ceramics, aluminum having alumite coating on the surface, etc. In this embodiment, a metal plate (support member) that functions as a pedestal electrode ) 42, a spacer plate 43 made of ceramics, a guide cylinder 44 made of ceramics, a metal ground shield 45, and a ring 46 surrounding the substrate mounting plate 41. A substrate mounting plate 41 that constitutes the uppermost portion of the substrate susceptor 33 is fixed to the upper surface of the metal plate 42.

  The substrate mounting plate 41 has a thin disk shape as a whole and has a circular outer shape in plan view. The upper end surface of the substrate mounting plate 41 functions as a substrate mounting surface 41a on which the support substrate 11 to which the crystal substrate 9 is bonded is mounted.

  Bipolar electrostatic chucking electrodes 47A and 47B are built in the vicinity of the substrate mounting surface 41a of the substrate mounting plate 41. A DC voltage for electrostatic attraction is applied to the electrodes 47A and 47B for electrostatic attraction from DC voltage application mechanisms 51A and 51B including a DC power supply 48 and an adjustment resistor 49 and the like. Instead of the bipolar electrode for electrostatic attraction, a monopolar type electrode for electrostatic attraction may be used.

  11A, FIG. 11B, FIG. 15A, and FIG. 15B together, when the support substrate 11 is placed on the substrate placement surface 41a, the substrate placement surface 41a and the lower surface 11b of the support substrate 11 are A large number of recesses 41b communicating with each other are formed so as to form a minute space or gap closed between them. The substrate mounting surface 41 a is provided with a supply hole 41 c for supplying heat transfer gas (He in this embodiment) to the gap between the substrate mounting surface 41 a and the support substrate 11. These supply holes 41 c are connected to the heat transfer gas supply mechanism 52. The heat transfer gas supply mechanism 52 includes a heat transfer gas source (He gas source in the present embodiment) 53, a supply channel 54 extending from the heat transfer gas source 53 to the supply hole 41c, and a heat transfer gas source 53 of the supply channel 54. A flow meter 56, a flow control valve 57, and a pressure gauge 58 are provided in that order from the side. The heat transfer gas supply mechanism 52 includes a discharge channel 59 that branches from the supply channel 54, and a cut-off valve 60 provided in the discharge channel 59. Furthermore, the heat transfer gas supply mechanism 52 includes a bypass flow path 61 that connects the supply hole 41 c side to the discharge flow path 59 with respect to the pressure gauge 58 of the supply flow path 54. When supplying heat transfer gas, the cut-off valve 60 is closed, and the heat transfer gas is sent from the heat transfer gas source 53 to the supply hole 41 c through the supply flow path 54. The controller 62 controls the flow rate control valve 57 based on the flow rate and pressure of the supply flow path 54 detected by the flow meter 56 and the pressure gauge 58. On the other hand, when the heat transfer gas is discharged, the cut-off valve 60 is opened, and the heat transfer gas between the lower surface 11b of the support substrate 11 and the substrate mounting surface 41a passes through the supply hole 41c, the supply flow path 54, and the discharge flow path. The air is exhausted from the exhaust port 54 via 59.

  The heat transfer gas supply channels 54 in the substrate mounting plate 41 are configured as a plurality of channels extending in the vertical direction (the thickness direction of the substrate mounting plate 41) toward the individual supply holes 41c. That is, the supply flow path 54 in the substrate mounting plate 41 does not include a portion extending in the horizontal direction or a branching portion. Therefore, the electrostatic chucking electrode 47 can be disposed in the vicinity of the substrate placement surface 41a, and the support substrate 11 can be firmly adsorbed to the substrate placement surface 41a with relatively little electric power.

  A high frequency applying mechanism 63 that applies a high frequency as a bias voltage is electrically connected to the metal plate 42. The high frequency application mechanism 63 includes a high frequency power supply 64 and a variable capacitor 65 for matching.

  A cooling mechanism 66 for cooling the metal plate 42 is provided. The cooling mechanism 66 includes a refrigerant flow path 67 formed in the metal plate 42, and a refrigerant circulation device 68 that circulates the temperature-controlled refrigerant in the refrigerant flow path 67.

  In the chamber 28, there are provided lifting pins 72 that pass through the substrate susceptor 33 and are driven by a driving device 71 to move up and down. When the support substrate 11 is carried in, the elevating pins 72 are in a raised position where the upper end protrudes from the substrate susceptor 33. The support substrate 11 is placed on the upper end of the elevating pins 72 at the raised position. From this state, the support pins 11 are placed on the substrate susceptor 33 as the elevating pins 72 are lowered. On the other hand, when the support substrate 11 is unloaded after the plasma processing is finished, the elevating pins 72 are raised to lift the support substrate 11 from the substrate susceptor 33.

  Next, the steps executed by the crystal device manufacturing apparatus 1 will be described in detail with reference to the flowchart of FIG. 8 and the schematic diagrams of FIGS. 9 to 16.

  First, the support substrate 11 is cleaned by the cleaning device 2 (step S1, FIG. 9 in FIG. 8). As a cleaning method, there is a cleaning method combining alkaline cleaning and acid cleaning called RCA cleaning used for particle removal and pure water cleaning. Next, the adhesive film 21 is affixed to the upper surface 11a of the washed support substrate 11 (step S2 in FIG. 8, FIG. 9). The sticking of the adhesive film 21 to the support substrate 11 is performed by vacuum sticking in the chamber 22 of the vacuum sticking apparatus 3 as described above. Therefore, the pressure-sensitive adhesive film 21 can be attached to the support substrate 11 in a state where the degree of adhesion of the pressure-sensitive adhesive film 21 to the support substrate 11 is high and no air bubbles are interposed between the pressure-sensitive adhesive film 21 and the support substrate 11. Further, since the support substrate 11 is washed before the adhesive film 21 is attached, no dust or the like is interposed between the adhesive film 21 and the support substrate 11. Also in this respect, the pressure-sensitive adhesive film 21 can be attached so as to have a high degree of adhesion to the support substrate 11. If the pressure-sensitive adhesive film 21 is heated and softened when being attached to the support substrate 11, the degree of adhesion of the pressure-sensitive adhesive film 21 to the support substrate 11 can be further increased. As specific conditions for vacuum application, for example, the degree of vacuum in the chamber 22 (based on absolute vacuum) is about 50 to 300 Pa, and the stage temperature is about room temperature to about 80 ° C.

  Next, the five crystal substrates 9 are bonded to the support substrate 11 via the adhesive film 21 by the vacuum bonding apparatus 4 (step S3 in FIG. 8, FIG. 10). As schematically shown in FIG. 10, a fixed portion 74 and a movable portion 75 located above the fixed portion 74 are accommodated in the chamber 73 of the vacuum bonding apparatus 4. The support substrate 11 has the lower surface 11b side fixed to the upper end surface of the fixing portion 74, and the upper surface 11a to which the adhesive film 21 has been vacuum-applied is in an upward posture. Each crystal substrate 9 has a front surface 9 a fixed to the lower end surface of the movable portion 75 and a back surface 9 b in a downward posture. In this state, the inside of the chamber 73 is depressurized to a predetermined degree of vacuum. Next, the movable part 75 moves downward in the vertical direction, whereby the back surface 9 b of the quartz substrate 9 is pushed into the adhesive film 21 on the support substrate 11. The quartz substrate 9 is pushed into the pressure-sensitive adhesive film 21 to such a depth that at least the mask layer 13b formed on the back surface 9b is completely buried in the pressure-sensitive adhesive film 21. As specific conditions for vacuum bonding, for example, the degree of vacuum in the chamber 22 (based on absolute vacuum) is about 100 to 750 Pa, the stage temperature is about room temperature to 80 ° C., and the quartz substrate 9 is attached to the support substrate 11. The pressing pressure is about 0.1 to 1 MPa.

  Thus, the quartz substrate 9 is bonded to the support substrate 11 via the adhesive film 21 by vacuum bonding in the chamber 22 of the vacuum bonding apparatus 4. Therefore, there are no bubbles between the pressure-sensitive adhesive film 21 and the quartz substrate 9, and the degree of adhesion of the quartz substrate 9 to the pressure-sensitive adhesive film 21 is high. In addition, since at least the mask layer 13b formed on the back surface 9b of the quartz substrate 9 is completely embedded in the adhesive film 21, the contact area between the quartz substrate 9 and the adhesive film 21 is large.

  When the crystal substrate 9 and the pressure-sensitive adhesive film 21 are pressed and bonded together by the vacuum bonding apparatus 4, the pressure-sensitive adhesive film 21 may be heated. Since the pressure-sensitive adhesive film 12 is softened by heating, the pressure-sensitive adhesive film 21 surely enters the concavo-convex portion of the back surface 9b of the quartz substrate 9 formed by the mask layer 13b.

  Next, dry etching of the surface 9a of the quartz substrate 9 is performed by the dry etching apparatus 6 (step S4 in FIG. 8, FIGS. 3, 11A, and 11B).

  First, the support substrate 11 on which the five quartz crystal substrates 9 are bonded via the adhesive film 21 is carried into the chamber 28 of the dry etching apparatus 6 from the gate 34 by an arm (not shown), and the lower surface 11b is placed on the substrate. It is mounted on the surface 41a. Specifically, the lower surface 11b of the support substrate 11 is placed on the upper end of the lifting pins 72 (raised position) positioned above the substrate placement surface 41a. Thereafter, the elevating pins 72 are lowered by the driving device 71, whereby the lower surface of the support substrate 11b is placed on the substrate placement surface 41a. The quartz substrate 9 is carried into the chamber 28 and placed on the substrate placement plate 41 in a state where the quartz substrate 9 is bonded to the support substrate 11 via the adhesive film 21. As described above, the quartz substrate 9 of the present embodiment has a thickness T′1 of about 100 μm and is very thin. 9 can be reliably prevented.

  A DC voltage is applied from the DC voltage application mechanism 51 to the electrostatic attraction electrode 47 built in the substrate mounting plate 41, and the lower surface 11b of the support substrate 11 (the conductive film 19 is formed as described above). ) Is electrostatically attracted to the substrate placement surface 41a. The support substrate 11 is held on the substrate placement surface 41a with high adhesion by electrostatic attraction.

  Subsequently, heat transfer gas (He in the present embodiment) is supplied from the heat transfer gas supply mechanism 52 through the supply hole 41c, and is transferred to the gap between the substrate mounting surface 41a and the support substrate 11 formed by the recess 41b. Filled with hot gas.

  Thereafter, the etching gas is supplied from the etching gas supply source 37 into the chamber 28 through the etching gas supply port 36, and evacuation by the vacuum exhaust device 39 is executed, so that the inside of the chamber 28 is maintained at a predetermined pressure. Subsequently, a high frequency voltage is applied from the high frequency power source 32 to the ICP coil 30, and a bias voltage is applied to the metal plate 42 of the substrate susceptor 33 by the high frequency application mechanism 63 to ionize the etching gas to generate the plasma P in the chamber 28. generate. The surface 9a of the quartz crystal substrate 9 is etched by the plasma P. Specifically, a portion of the surface 9a of each crystal substrate 9 that is not covered with the mask layer 13a, that is, a portion outside the outer contour of the crystal vibrating piece 8 and a portion of the groove 8d are etched. Since five crystal substrates 9 are attached to one support substrate 11, this dry etching is a batch process.

  In order to increase the etching rate of the quartz substrate 9, it is necessary to apply a high bias voltage to the metal plate 42 with a high plasma density. Further, since the quartz substrate 9 has a high hardness, the etching time becomes long even if the plasma density is increased and a high bias voltage is applied. Therefore, the quartz substrate 9 is exposed to heat from the plasma for a long time, and the heat absorption from the plasma is remarkable. The quartz substrate 9 is about 100 μm and is very thin and brittle. Therefore, assuming that the quartz substrate 9 is not sufficiently cooled, damage such as warpage due to heat and cracks resulting from the warpage occurs. Further, the higher the temperature of the quartz substrate 9, the greater the internal stress due to the difference in the coefficient of thermal expansion between the quartz substrate 9 and the mask layers 13a and 13b, causing damage such as warping and cracking. Furthermore, when the quartz substrate 9 is moved to a high temperature of about 400 ° C. to 500 ° C., the quartz itself is altered. However, in this embodiment, since the quartz substrate 9 can be cooled and maintained at a relatively low temperature with high efficiency and high accuracy, the etching conditions required for dry etching of the quartz substrate 9 (high plasma density, high bias voltage, In addition, the quartz substrate 9 can be prevented from being damaged due to heat while satisfying a long processing time. Hereinafter, this point will be described in detail.

  During the etching, the coolant is circulated in the coolant channel 67 by the coolant circulation device 68 to cool the metal plate 42, thereby cooling the crystal substrate 9 on the support substrate 11. The quartz substrate 9 is cooled by heat conduction between the adhesive film 21, the support substrate 11, the heat transfer gas, and the metal plate 42 via the substrate mounting plate 41. Since the adhesive film 21 is attached to the support substrate 11 by vacuum bonding, the degree of adhesion of the adhesive film 21 to the support substrate 11 is high, and no bubbles are interposed between the adhesive film 21 and the support substrate 11. Moreover, since the quartz substrate 9 is bonded to the support substrate 11 via the adhesive film 21 by vacuum bonding, the degree of adhesion of the quartz substrate 9 to the adhesive film 21 is high, and the quartz substrate 9 and the adhesive film 21 are bonded. There are no air bubbles between them. In addition, the quartz substrate 9 is pushed into the adhesive film 21 to a sufficient depth, and the contact area between the two is large. Therefore, the thermal conductivity between the support substrate 11 and the pressure-sensitive adhesive film 21 and the thermal conductivity between the pressure-sensitive adhesive film 21 and the quartz substrate 9 are both good. In addition, since the support substrate 11 is held with high adhesion to the substrate placement surface 41a by electrostatic adsorption, and is filled with a heat transfer gas between the support substrate 11 and the substrate placement surface 41a, The thermal conductivity between the support substrate 11 and the substrate mounting plate 41 is also good. Since the thermal conductivity between the substrate mounting plate 41 and the quartz substrate 9 is thus good, the quartz substrate 9 during dry etching can be cooled with high efficiency and high accuracy. By cooling the quartz substrate 9 with high efficiency and high accuracy, the quartz substrate 9 is maintained at about 100 ° C. or less even under etching conditions of high plasma density, high bias voltage, and long processing time (for example, about 80 minutes). it can. As a result, it is possible to prevent the quartz substrate 9 from being warped, peeled off, cracked, or deteriorated during the dry etching. Further, damage such as warpage, peeling and cracking of the quartz substrate 9 due to peeling of the adhesive film 21 from the quartz substrate 9 and the support substrate 11 and expansion of bubbles due to heat during dry etching can be prevented. Furthermore, by cooling the quartz substrate 9 with high efficiency and high accuracy, internal stress due to the difference in thermal expansion coefficient between the quartz constituting the quartz substrate 9 and the metal constituting the mask layers 13a and 13b can be reduced. Damage due to stress can also be prevented. Furthermore, since the quartz substrate 9 does not reach a high temperature due to highly efficient and highly accurate cooling, it is possible to prevent the quartz itself from being altered by heat.

  As described above, the quartz substrate 9 is pushed into the pressure-sensitive adhesive film 21 to such a depth that the mask layer 13b formed on at least the back surface 9b is completely buried in the pressure-sensitive adhesive film 21. Thus, by embedding the back surface 9b of the quartz substrate 9 in the adhesive film 21 to a sufficient depth, it is possible to prevent plasma from entering the boundary between the back surface 9b of the quartz substrate 9 and the adhesive film 21. When the plasma wraps around the boundary between the back surface 9 b of the quartz substrate 9 and the adhesive film 21, the adhesive film 21 at this boundary portion is etched, causing peeling of the quartz substrate 9 from the adhesive film 21. By embedding the quartz substrate 9 to a sufficient depth in the adhesive film 21 to prevent the plasma from wrapping around, the peeling of the quartz substrate 9 from the adhesive film 21 can be prevented, and the quartz substrate 9 is attached to the support substrate 11. The adhesive film 21 can be maintained in close contact.

  As described above, the entire upper surface 11 a of the support substrate 11 is covered with the adhesive film 21, and the upper surface 11 a itself is not exposed even in the portion of the upper surface 11 a of the support substrate 11 where the crystal substrate 9 is not bonded. It is covered with the adhesive film 21. Therefore, the support substrate 11 can be prevented from being etched during the dry etching of the quartz substrate 9. As a result, contamination due to the material etched away from the support substrate can be prevented. Further, since the support substrate 11 is not dry-etched, the service life is extended. Further, by covering the entire upper surface 11 a of the support substrate 11 with the adhesive film 21, the plasma wraps around the boundary between the back surface 9 b of the quartz substrate 9 and the adhesive film 21 described above, and the quartz substrate 9 resulting therefrom The peeling from the adhesive film 21 can be prevented more reliably.

  As schematically shown in FIG. 11B, when the outside of the outer contour of the quartz crystal vibrating piece 8 is etched to a depth of ½ of the outer cross section of the quartz crystal vibrating piece 8, and the etching depth of the groove 8d reaches the bottom. Then, the etching of the surface 9a of the quartz substrate 9 is finished. The depth at which the crystal substrate 9 is pushed into the adhesive film 21 is such that the height from the support substrate 11 to the surface of the adhesive film 21 at the end of etching of the surface 9a of the crystal substrate 9 is as follows. It is preferable to set according to the selection ratio of the quartz substrate 11 and the pressure-sensitive adhesive layer 21 so as to be higher than the height up to the back surface 9b. Thereby, it is possible to more reliably prevent the plasma from entering the boundary between the back surface 9b of the quartz substrate 9 and the adhesive film 21 until the etching of the front surface 9a of the quartz substrate 9 is completed.

Specific etching conditions in this embodiment are as follows. The etching gas is a C ₄ F ₈ / He mixed gas, and the flow rate of each gas is 30 sccm for C ₄ F _{8 and} 120 sccm for He. The pressure in the chamber 28 is 0.5 Pa. The high frequency power applied to the ICP coil 30 is 1500 W, and the bias power applied to the metal plate 42 is 700 W. The voltage applied to the electrostatic adsorption electrode 47 is ± 1.2 kV. The filling pressure of the heat transfer gas (He in this embodiment) into the gap between the support substrate 11 and the substrate mounting surface 41a is 1200 Pa. The temperature of the substrate susceptor 33 is maintained at about 20 ° C., whereby the temperature of the quartz substrate 9 is maintained at about 100 ° C. or less. Under this etching condition, the etching rate of the quartz substrate 9 is 0.5 to 1.0 μm. The etching selectivity of the mask layers 13a and 13b made of a metal such as Ni or Cr is about 20 to 40. The etching time is about 40 to 80 minutes. The etching gas is not limited to the C ₄ F ₈ / He mixed gas. Instead of C ₄ F ₈ , other fluorocarbon gases can be used. For _example, can be used _{CHF 3, CF 4, C 4} F 6, C 5 F 8, CH 2 F 2 or the like. Other than the fluorocarbon-based gas, SF ₆ , NF ₃ or the like can be used. In addition, other rare gas may be used instead of He.

  After the etching of the surface 9 a of the quartz substrate 9 is completed, the support substrate 11 to which the quartz substrate 9 is bonded is carried out of the chamber 28 of the dry etching apparatus 6 from the gate 34. At this time, the elevating pins 72 are first lifted by the driving device 71 so that the support substrate 11 is separated from the substrate placement surface 41a, and then the support substrate 11 is carried out of the chamber 28 by an arm (not shown). By handling in a state of being bonded to the support substrate 11, damage to the quartz substrate 9 due to an external force acting during unloading can be reliably prevented.

  Next, the quartz substrate 9 is peeled from the support substrate 11 (step S5 in FIG. 8, FIG. 12). Specifically, the crystal substrate 9 is peeled from the support substrate 11 by removing the pressure-sensitive adhesive film 21 on which the crystal substrate 9 is bonded to the support substrate 11 by the wet etching apparatus 7. In this embodiment, since the adhesive film 21 consists of a polyimide-type adhesive, organic solvents, such as acetone and NMP (N-methyl-pyrrolidone), are used as a chemical | medical solution. However, the type of the chemical solution is appropriately selected according to the material of the adhesive film 21. The support substrate 11 on which the crystal substrate 9 is bonded is immersed in the chemical solution. During immersion, the chemical solution is stirred (if the quartz substrate 9 is not damaged, ultrasonic vibration may be added to the chemical solution). When the quartz substrate 9 is peeled from the support substrate 11 by wet etching, the mechanical stress acting on the quartz substrate 9 that causes damage such as cracking is removed when the quartz substrate 9 is peeled from the support substrate 11. It can be minimized. Further, in the five regions of the support substrate 11 to which the crystal substrate 9 is bonded, the chemical solution is introduced into the adhesive film 21 through the through-holes 11d penetrating in the thickness direction. The quartz crystal substrate 9 can be quickly peeled from the support substrate 11 while further reducing the stress. Specifically, when a through hole 11d (or a groove 11f shown in FIG. 19 described later) is provided in the support substrate 11 as in this embodiment, the time required for peeling is about 6 to 20 hours. On the other hand, when the support substrate 11 has a simple plate shape in which neither the through hole 11d nor the groove 11f is provided, the time required for peeling is about 30 to 45 hours.

  The etching of the surface 9a of the quartz substrate 9 is completed by the above steps (Steps S1 to S5 in FIG. 8).

  Next, etching of the back surface 9b of the quartz substrate 9 is performed. This back surface 9b etching process (steps S6 to S10 in FIG. 8) is a repetition of the same process as the front surface 9a etching process (steps S1 to 5 in FIG. 8). Hereinafter, although the etching process of the back surface 9b will be described, the points not particularly mentioned are the same as in the etching of the front surface 9a.

  First, after the support substrate 11 is cleaned by the cleaning device 2 (steps S6 and 13 in FIG. 8), the adhesive film 21 is applied to the entire upper surface 11a of the support substrate 11 by vacuum application using the vacuum application device 3 ( Step S7 in FIG. 8, FIG. 13). Before the adhesive film 21 is attached, the support substrate 11 is washed to remove dust and the like, and the adhesive film 21 is attached by vacuum application. Therefore, the adhesive film 21 is attached to the support substrate 11 with dust, bubbles, etc. It can affix in the state which has the high adhesiveness which does not interpose.

  Next, the five crystal substrates 9 are bonded to the support substrate 11 by the vacuum bonding apparatus 4 through the adhesive film 21 by vacuum bonding (step S8 in FIG. 8, FIG. 14). As schematically shown by an arrow A in FIG. 12, the quartz substrate 9 is turned upside down so that the unetched back surface 9 b faces upward and the front surface 9 a faces downward, and the front surface 9 a is pushed into the adhesive film 21 on the support substrate 11. . A step is generated on the surface 9a of the quartz substrate 9 by dry etching (step S4 in FIG. 8). The quartz substrate 9 is pushed into the pressure-sensitive adhesive film 21 to such a depth that at least the processing step formed on the surface 9 a is completely buried in the pressure-sensitive adhesive film 21. Since the crystal substrate 9 is bonded to the support substrate 11 via the adhesive film 21 by vacuum bonding, there is no air bubble between the adhesive film 21 and the crystal substrate 9, and the crystal substrate 9 adheres to the adhesive film 21. High degree. In addition, since at least the processing step of the quartz substrate 9 is completely embedded in the adhesive film 21, the contact area between the quartz substrate 9 and the adhesive film 21 is large. If the pressure-sensitive adhesive film 21 is heated when the quartz substrate 9 and the pressure-sensitive adhesive film 21 are pressed together, the pressure-sensitive adhesive film 12 is softened by heating, and the pressure-sensitive adhesive film 21 surely enters the unevenness due to the processing step.

  Next, dry etching is performed on the back surface 9b of the quartz substrate 9 by the dry etching apparatus 6 (step S9 in FIG. 8, FIGS. 3, 15A, and 15B). As schematically shown in FIG. 15B, outside the outer contour of the quartz crystal vibrating piece 8, half of the outer cross section of the quartz crystal vibrating piece 8 that remains without being removed by etching of the surface 9 a is etched. The etching of the back surface 9b of the quartz substrate 9 is continued until the etching depth of the groove 13e reaches the bottom. When the etching of the back surface 9b is completed, the thickness direction of the quartz substrate 9 excluding the branch frame portion 18, the annular frame portion 14, and the straight frame portions 15a and 15b in the region outside the outer contour of the quartz crystal resonator element 8. The crystal is removed as a whole, and an opening penetrating the crystal substrate 9 in the thickness direction is formed. Further, grooves 8d and 8e are formed on both surfaces of the individual arm portions 8b and 8c.

  Since the quartz substrate 9 is pasted by vacuum bonding to the adhesive film 21 pasted on the cleaned support substrate 11 by vacuum pasting, the degree of adhesion between the quartz substrate 9 and the support substrate 11 with respect to the adhesive film 21 In addition, dust and bubbles do not intervene, and in addition, since the quartz substrate 9 is pushed into the adhesive film 21 to a sufficient depth and the contact area between both is large, the thermal conductivity is good. In addition, since the support substrate 11 is held with high adhesion to the substrate placement surface 41a by electrostatic adsorption, and is filled with a heat transfer gas between the support substrate 11 and the substrate placement surface 41a, The thermal conductivity between the support substrate 11 and the substrate placement surface 41a is also good. Therefore, the crystal substrate 9 can be maintained at about 100 ° C. or less even under etching conditions of high plasma density, high bias voltage, and long processing time (for example, about 80 minutes). The deterioration of the crystal itself can be prevented. In particular, since the heat conduction from the quartz substrate 9 to the support substrate 11 is proportional to the square of the shortest distance between the two, when the processing depth of the surface 9a of the quartz substrate 9 is large (for example, the processing depth is twice the etching width). In the above case, the thermal conductivity between the quartz substrate 9 and the support substrate 11 is lowered, but the surface 9a of the quartz substrate 9 where the processing step is generated is sufficiently deep in the adhesive film 21. By embedding to this extent, this decrease in thermal conductivity can be suppressed.

  Further, since the surface 9a of the quartz substrate 9 is pushed into the pressure-sensitive adhesive film 21 to such a depth that the processing step is filled, the plasma wraps around the boundary between the surface 9a of the quartz substrate 9 and the pressure-sensitive adhesive film 21 and the result. The peeling of the quartz substrate 9 from the adhesive film 21 can be prevented. Therefore, the quartz substrate 9 can be maintained in close contact with the support substrate 11 via the adhesive film 21. The depth at which the crystal substrate 9 is pushed into the adhesive film 21 is such that the height from the support substrate 11 to the surface of the adhesive film 21 at the end of etching of the back surface 9b of the crystal substrate 9 is as follows. It is preferable to set according to the selection ratio of the crystal substrate 11 and the pressure-sensitive adhesive layer 21 so as to be higher than the height up to the surface 9a. Thereby, it is possible to more reliably prevent the plasma from entering the boundary between the front surface 9b of the quartz substrate 9 and the adhesive film 21 until the etching of the back surface 9b of the quartz substrate 9 is completed.

  Furthermore, since the entire upper surface 11a of the support substrate 11 is covered with the adhesive film 21, etching of the support substrate 11 and contamination caused by the etching can be prevented, the service life of the support substrate 11 is extended, and the plasma wraps around. The resulting peeling of the quartz substrate 9 from the adhesive film 21 can also be prevented.

  Furthermore, since the quartz substrate 9 is carried into and out of the chamber 28 of the dry etching apparatus 6 while being bonded to the support substrate 11, damage to the quartz substrate 9 due to an external force acting during loading and unloading can be prevented.

  Finally, the pressure-sensitive adhesive film 21 is removed by the wet etching device 75, and the quartz substrate 9 is peeled from the support substrate 11 (step S10 in FIG. 8, FIG. 16). Since the quartz substrate 9 is peeled from the support substrate 11 by wet etching, mechanical stress acting on the quartz substrate 9 that causes damage such as cracking can be minimized.

  After both the surfaces of the quartz substrate 9 are dry-etched by the above steps to form individual quartz crystal vibrating pieces 8, subsequent steps such as removal of the metal layers 12a and 12b and formation of other electrodes are performed as necessary.

  As described above, since the quartz substrate 9 is bonded to the support substrate 11 via the adhesive film 21, damage to the quartz substrate 9 due to an external force acting during handling such as loading / unloading into / from the chamber 28 of the dry etching apparatus 6 is ensured. Can be prevented. Further, the support substrate 11 obtained by vacuum-bonding the quartz substrate 9 via the vacuum-adhered adhesive film 21 is held with high adhesion to the substrate placement surface 41a by electrostatic adsorption, and the support substrate 11 and the substrate placement surface are provided. Since dry etching is performed in a state where a heat transfer gas is supplied to and from 41a, the quartz substrate 9 can be cooled with high efficiency and high accuracy, and the quartz substrate can be warped, peeled, cracked, etc. It can prevent its own alteration. In particular, in these respects, the method of the present embodiment can finely process a very thin substrate made of a crystal having high hardness and brittleness by dry etching without causing damage such as warpage, cracking, or alteration of the crystal itself due to heat. This is a practically practical method.

(Second Embodiment)
Referring to FIG. 17, the crystal device manufacturing apparatus 1 in this embodiment includes an ashing apparatus 10 in addition to the cleaning apparatus 2, the vacuum bonding apparatus 3, the vacuum bonding apparatus 4, the dry etching apparatus 6, and the wet etching apparatus 7. . Referring also to FIG. 18, the ashing apparatus is performed after dry etching (step S4) of the surface 9a of the quartz substrate 9 and before peeling the quartz substrate 9 from the support substrate 11 by wet etching (step S5). 10 performs ashing (step S5 ′). Further, by this ashing device 10, the ashing 10 is performed after the dry etching (step S9) of the back surface 9b of the quartz substrate 9 and before the separation of the quartz substrate 9 from the support substrate 11 by the wet etching (step S10). As a result, ashing is executed (step S10 ′). In the ashing process in steps S5 ′ and S10 ′, the height from the support substrate 11 to the surface of the pressure-sensitive adhesive film 21 is set to the surface on the support substrate 11 side of the crystal substrate 9 from the support substrate 11 (on the back surface 9a in step S5 ′). In S10 ′, the height is made lower than the height up to the surface 9a). When the pressure-sensitive adhesive film 21 is removed to this height, the wet etching chemicals easily enter the boundary between the crystal substrate 9 and the pressure-sensitive adhesive film 21 (the bonding surface of the substrate to the pressure-sensitive adhesive layer) from the side wall of the crystal substrate 9. The time required to peel the substrate 9 from the support substrate 11 can be shortened.

  Since other configurations and operations of the second embodiment are the same as those of the first embodiment, the same elements are denoted by the same reference numerals and description thereof is omitted.

  The present invention is not limited to the above-described embodiment, and various modifications are possible as exemplified below.

  As shown in FIG. 19, a groove 11 f may be provided in a region of the upper surface 11 a of the support substrate 11 where the crystal substrate 9 is bonded. In this example, the groove 11f is provided at a position corresponding to the annular frame portion 14 and the straight frame portions 15a and 15b (see also FIG. 6) of the mask layers 13a and 13b. Further, the groove 11f in this example has a groove width of about 50 to 300 μm, and the cross section is an arc-shaped strip. As conceptually indicated by a broken line arrow in FIG. 19, even when the groove 11 f is provided, when the quartz substrate 9 is separated from the support substrate 11 by wet etching, the boundary between the quartz substrate 9 and the adhesive film 21 (crystal The chemical solution can easily enter the bonding surface of the substrate 9 to the adhesive film 21), and the time required for peeling the quartz substrate 9 from the support substrate 11 can be shortened.

  An adhesive layer may be formed on the support substrate by applying a liquid adhesive instead of vacuum bonding of the adhesive film. For example, an adhesive may be applied to the support substrate by spin coating or the like. In this case, a spin coater is required instead of the vacuum applicator 3. However, a thick adhesive layer can be formed on the support substrate with higher accuracy and reproducibility when the adhesive film is applied as in the first and second embodiments than when the adhesive is applied by a spin coater.

  The peeling of the quartz substrate 9 from the support substrate 11 is not limited to wet etching of the adhesive layer. For example, the adhesive surface of the quartz substrate 9 and the support substrate 11 can be peeled off by ultraviolet rays using an ultraviolet release film as the pressure-sensitive adhesive layer and a conductive film through which ultraviolet rays pass as the support substrate.

  Although the present invention has been described by taking as an example the case of manufacturing a tuning fork type crystal vibrating piece, the present invention can also be applied to manufacturing other types of crystal vibrating pieces and crystal devices other than crystal vibrating pieces. The present invention has been described by taking the case of the quartz substrate 9 having a thickness T′1 of about 100 μm as an example. For example, the thickness is 200 μm or less, particularly about 100 μm or less, and it is very thin and brittle. The quartz crystal device can be manufactured by microfabrication of a quartz substrate that is easily cracked.

The block diagram of the crystal device manufacturing apparatus in 1st Embodiment. The typical perspective view of a vacuum sticking apparatus. Schematic sectional view of a dry etching apparatus. The perspective view of a crystal oscillator. Sectional drawing in the IV-IV line of FIG. 4A. The perspective view of a support substrate and a quartz substrate. The top view of a quartz substrate. The typical perspective view of the support substrate in which the adhesive layer was formed. The typical perspective view of bonding to the support substrate of a quartz crystal substrate via an adhesion layer. The typical perspective view of the support substrate by which the crystal substrate was bonded together through the adhesion layer. The typical perspective view of peeling of the quartz substrate from a support substrate. The flowchart which shows the manufacture procedure of the quartz substrate in 1st Embodiment. The typical side view which shows washing | cleaning of a support substrate, and adhesion | attachment (1st time) of an adhesive layer. The typical side view which shows bonding of the quartz substrate (back surface) to the support substrate through an adhesive layer. The typical side view which shows the time of the dry etching start of a quartz substrate (surface). The typical side view which shows the time of completion | finish of the dry etching of a quartz substrate (surface). The typical side view which shows peeling by the wet etching from the support substrate of a quartz substrate (back surface). The typical side view which shows washing | cleaning of a support substrate, and adhesion | attachment (2nd time) of an adhesive layer. The typical side view which shows the bonding of the quartz substrate (surface) to the support substrate through the adhesive layer. The typical side view which shows the time of the dry etching start of a quartz substrate (back surface). The typical side view which shows the time of completion | finish of the dry etching of a quartz substrate (back surface). The typical side view which shows peeling by the wet etching from the support substrate of a quartz substrate (surface). The block diagram of the crystal device manufacturing apparatus in 2nd Embodiment. The flowchart which shows the manufacture procedure of the quartz substrate in 2nd Embodiment. The typical perspective view which shows the alternative of a support substrate.

DESCRIPTION OF SYMBOLS 1 Crystal device manufacturing apparatus 2 Cleaning apparatus 3 Vacuum bonding apparatus 4 Vacuum bonding apparatus 6 Dry etching apparatus 7 Wet etching apparatus 8 Crystal vibrating piece 8a Base part 8b, 8c Arm part 8d, 8e Groove 9 Crystal substrate 9a Surface 9b Back surface 9c Orientation flat DESCRIPTION OF SYMBOLS 10 Ashing apparatus 11 Support substrate 11a Upper surface 11b Lower surface 11c Notch 11d Through-hole 12a, 12b Metal layer 13a, 13b Mask layer 14 Annular frame part 15a, 15b Linear frame part 16 Device formation part 17 Opening 18 Branch frame part 19 Conductive film 21 Adhesive film 22 Chamber 23a, 23b Cover film 24 Supply roll 26 Peeling roll 27 Peeling tape 28 Chamber 29 Top plate 30 ICP coil 31 Matching circuit 32 High frequency power supply 33 Substrate susceptor 34 Gate 36 Etch Gugasu supply opening 37 an etching gas supply source 38 exhaust port 39 vacuum exhaust apparatus 40
DESCRIPTION OF SYMBOLS 41 Substrate mounting plate 41a Substrate mounting surface 41b Recessed portion 41c Supply hole 42 Metal plate 43 Spacer plate 44 Guide cylinder 45 Ground shield 46 Ring 47 Electrostatic adsorption electrode 48 DC power supply 49 Resistance 51 DC voltage application mechanism 52 Heat transfer gas Supply mechanism 53 Heat transfer gas source 54 Supply flow path 56 Flow meter 57 Flow control valve 58 Pressure gauge 59 Discharge flow path 60 Cut-off valve 61 Bypass flow path 62 Controller 63 High frequency application mechanism 64 High frequency power supply 65 Variable capacity capacitor 66 Cooling mechanism 67 Refrigerant flow path 68 Refrigerant circulation device 71 Drive device 72 Lifting pin 73 Chamber 74 Fixed part 75 Movable part

Claims (10)

A vacuum vessel to which an etching gas is supplied, a plasma generation source for generating plasma by ionizing the etching gas in the vacuum vessel, and a substrate mounting made of a dielectric and disposed on the bottom side in the vacuum vessel Etching, an electrostatic chucking electrode built in the substrate mounting unit, and a heat transfer gas supply mechanism for supplying a heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting unit Prepare the equipment,
Preparing a quartz substrate in which mask layers corresponding to the shape of the quartz crystal device are respectively formed on the first and second surfaces facing each other;
Preparing a support substrate having a larger area than the quartz substrate;
Forming an adhesive layer on the first surface of the first and second surfaces of the support substrate facing each other;
The second surface of the quartz substrate is bonded to the first surface of the support substrate through the adhesive layer,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the first crystal substrate. Etching the surface to a depth where a part of the outer cross section of the crystal device remains,
After completion of the etching of the first surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is unloaded from the vacuum container,
Removing the adhesive layer and peeling the quartz substrate from the support substrate;
After peeling the quartz substrate from the support substrate, the adhesive layer is formed again on the first surface of the support substrate,
The first surface of the quartz substrate that has been etched through the adhesive layer is bonded to the first surface of the support substrate,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the second of the quartz crystal substrate. Is etched to a depth at which the remaining part of the external cross section of the crystal device is removed,
After completion of the etching of the second surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is taken out of the vacuum vessel,
Removing the adhesive layer and peeling the quartz substrate from the support substrate ;
When the second surface of the quartz substrate is bonded to the support substrate through the adhesive layer, at least the mask layer formed on the second surface of the quartz substrate is embedded in the adhesive layer. A method for manufacturing a crystal device , wherein the crystal substrate is pushed into the adhesive layer to a depth . The depth at which the second surface of the quartz substrate is pushed into the pressure-sensitive adhesive layer is such that the height from the support substrate to the surface of the pressure-sensitive adhesive layer at the end of etching of the first surface of the quartz substrate is the support. The method for manufacturing a crystal device according to claim 1 , wherein the crystal device is set according to a selection ratio between the crystal substrate and the pressure-sensitive adhesive layer so as to be higher than a height from the substrate to the second surface of the crystal substrate. A vacuum vessel to which an etching gas is supplied, a plasma generation source for generating plasma by ionizing the etching gas in the vacuum vessel, and a substrate mounting made of a dielectric and disposed on the bottom side in the vacuum vessel Etching, an electrostatic chucking electrode built in the substrate mounting unit, and a heat transfer gas supply mechanism for supplying a heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting unit Prepare the equipment,
Preparing a quartz substrate in which mask layers corresponding to the shape of the quartz crystal device are respectively formed on the first and second surfaces facing each other;
Preparing a support substrate having a larger area than the quartz substrate;
Forming an adhesive layer on the first surface of the first and second surfaces of the support substrate facing each other;
The second surface of the quartz substrate is bonded to the first surface of the support substrate through the adhesive layer,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the first crystal substrate. Etching the surface to a depth where a part of the outer cross section of the crystal device remains,
After completion of the etching of the first surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is unloaded from the vacuum container,
Removing the adhesive layer and peeling the quartz substrate from the support substrate;
After peeling the quartz substrate from the support substrate, the adhesive layer is formed again on the first surface of the support substrate,
The first surface of the quartz substrate that has been etched through the adhesive layer is bonded to the first surface of the support substrate,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the second of the quartz crystal substrate. Is etched to a depth at which the remaining part of the external cross section of the crystal device is removed,
After completion of the etching of the second surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is taken out of the vacuum vessel,
Removing the adhesive layer and peeling the quartz substrate from the support substrate ;
When the first surface of the quartz substrate is bonded to the support substrate via the pressure-sensitive adhesive layer, at least a depth at which a processing step on the first surface of the quartz substrate caused by etching is embedded in the pressure-sensitive adhesive layer. A method for manufacturing a crystal device , wherein the crystal substrate is pushed into the pressure-sensitive adhesive layer . The depth at which the first surface of the quartz substrate is pushed into the pressure-sensitive adhesive layer is such that the height from the support substrate to the surface of the pressure-sensitive adhesive layer at the end of etching of the second surface of the quartz substrate is the support. The method for manufacturing a crystal device according to claim 3 , wherein the crystal device is set according to a selection ratio between the crystal substrate and the adhesive layer so as to be higher than a height from the substrate to the first surface of the crystal substrate. A vacuum vessel to which an etching gas is supplied, a plasma generation source for generating plasma by ionizing the etching gas in the vacuum vessel, and a substrate mounting made of a dielectric and disposed on the bottom side in the vacuum vessel Etching, an electrostatic chucking electrode built in the substrate mounting unit, and a heat transfer gas supply mechanism for supplying a heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting unit Prepare the equipment,
Preparing a quartz substrate in which mask layers corresponding to the shape of the quartz crystal device are respectively formed on the first and second surfaces facing each other;
Preparing a support substrate having a larger area than the quartz substrate;
Forming an adhesive layer on the first surface of the first and second surfaces of the support substrate facing each other;
The second surface of the quartz substrate is bonded to the first surface of the support substrate through the adhesive layer,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the first crystal substrate. Etching the surface to a depth where a part of the outer cross section of the crystal device remains,
After completion of the etching of the first surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is unloaded from the vacuum container,
Removing the adhesive layer and peeling the quartz substrate from the support substrate;
After peeling the quartz substrate from the support substrate, the adhesive layer is formed again on the first surface of the support substrate,
The first surface of the quartz substrate that has been etched through the adhesive layer is bonded to the first surface of the support substrate,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the second of the quartz crystal substrate. Is etched to a depth at which the remaining part of the external cross section of the crystal device is removed,
After completion of the etching of the second surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is taken out of the vacuum vessel,
Removing the adhesive layer and peeling the quartz substrate from the support substrate ;
The method for manufacturing a crystal device, wherein the support substrate has a conductive portion at least on the second surface . A vacuum vessel to which an etching gas is supplied, a plasma generation source for generating plasma by ionizing the etching gas in the vacuum vessel, and a substrate mounting made of a dielectric and disposed on the bottom side in the vacuum vessel Etching, an electrostatic chucking electrode built in the substrate mounting unit, and a heat transfer gas supply mechanism for supplying a heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting unit Prepare the equipment,
Preparing a quartz substrate in which mask layers corresponding to the shape of the quartz crystal device are respectively formed on the first and second surfaces facing each other;
Preparing a support substrate having a larger area than the quartz substrate;
Forming an adhesive layer on the first surface of the first and second surfaces of the support substrate facing each other;
The second surface of the quartz substrate is bonded to the first surface of the support substrate through the adhesive layer,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the first crystal substrate. Etching the surface to a depth where a part of the outer cross section of the crystal device remains,
After completion of the etching of the first surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is unloaded from the vacuum container,
Removing the adhesive layer and peeling the quartz substrate from the support substrate;
After peeling the quartz substrate from the support substrate, the adhesive layer is formed again on the first surface of the support substrate,
The first surface of the quartz substrate that has been etched through the adhesive layer is bonded to the first surface of the support substrate,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the second of the quartz crystal substrate. Is etched to a depth at which the remaining part of the external cross section of the crystal device is removed,
After completion of the etching of the second surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is taken out of the vacuum vessel,
Removing the adhesive layer and peeling the quartz substrate from the support substrate ;
Forming the pressure-sensitive adhesive layer on the entire surface of the support substrate;
The pressure-sensitive adhesive layer is made of a polyimide-based pressure-sensitive adhesive,
The method for producing a crystal device, wherein the chemical used in the wet etching is an organic solvent . A vacuum vessel to which an etching gas is supplied, a plasma generation source for generating plasma by ionizing the etching gas in the vacuum vessel, and a substrate mounting made of a dielectric and disposed on the bottom side in the vacuum vessel Etching, an electrostatic chucking electrode built in the substrate mounting unit, and a heat transfer gas supply mechanism for supplying a heat transfer gas to the substrate mounting surface which is the upper end surface of the substrate mounting unit Prepare the equipment,
Preparing a quartz substrate in which mask layers corresponding to the shape of the quartz crystal device are respectively formed on the first and second surfaces facing each other;
Preparing a support substrate having a larger area than the quartz substrate;
Forming an adhesive layer on the first surface of the first and second surfaces of the support substrate facing each other;
The second surface of the quartz substrate is bonded to the first surface of the support substrate through the adhesive layer,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the first crystal substrate. Etching the surface to a depth where a part of the outer cross section of the crystal device remains,
After completion of the etching of the first surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is unloaded from the vacuum container,
Removing the adhesive layer and peeling the quartz substrate from the support substrate;
After peeling the quartz substrate from the support substrate, the adhesive layer is formed again on the first surface of the support substrate,
The first surface of the quartz substrate that has been etched through the adhesive layer is bonded to the first surface of the support substrate,
The support substrate on which the quartz substrate is bonded is carried into a vacuum container of the dry etching apparatus, and the second surface of the support substrate is mounted on the substrate mounting surface,
Applying a DC voltage to the electrostatic adsorption electrode to electrostatically adsorb the support substrate to the substrate mounting surface,
While the heat transfer gas is supplied between the substrate mounting surface and the second surface of the support substrate by the heat transfer gas supply mechanism, plasma is generated by the plasma generation source to generate the second of the quartz crystal substrate. Is etched to a depth at which the remaining part of the external cross section of the crystal device is removed,
After completion of the etching of the second surface of the quartz substrate, the support substrate to which the quartz substrate is bonded is taken out of the vacuum vessel,
Removing the adhesive layer and peeling the quartz substrate from the support substrate ;
A method for producing a crystal device, wherein the pressure-sensitive adhesive layer is removed by wet etching . The method for manufacturing a crystal device according to claim 7 , wherein the pressure-sensitive adhesive layer is removed by an ashing process before the pressure-sensitive adhesive layer is removed and the crystal substrate is separated from the support substrate. The crystal device according to claim 8 , wherein the height from the support substrate to the surface of the pressure-sensitive adhesive layer is made lower by the ashing process than the height from the support substrate to the surface of the crystal substrate on the support substrate side. Production method. The said support substrate is a manufacturing method of the crystal device of Claim 7 provided with the groove | channel or through-hole for introducing the chemical | medical solution used for the said wet etching into the said adhesive layer.

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