JP6900799B2 - Through Silicon Via, Through Silicon Via Manufacturing Method and Mechanical Sensor - Google Patents

Description

The present disclosure relates to a through electrode substrate, a method for manufacturing a through electrode substrate, and a dynamic quantity sensor.

Some electronic devices require a structure that completely shuts off the outside air (medium airtight structure), and the structure that completely shuts off the outside air is called a hermetic seal. For example, in order to protect electronic components from environmental conditions such as humidity, dust, and heat in the air, it is necessary to have an airtight structure. Further, an electrode terminal is required to take out an output signal as a result of power supply or some sensing of the airtight electronic component. As the above electronic components, in particular, a mechanical quantity sensor that detects the absolute value of an external force (hydraulic pressure, atmospheric pressure, degree of vacuum) that changes from moment to moment is widely used in many industrial fields for precise control of a device. ing. For example, in the mechanical quantity sensor using a diaphragm, a small mechanical quantity sensor has also been developed. Patent Document 1 discloses a technique for measuring a pressure from a value of a capacitance generated between a diaphragm and a detection electrode provided so as to face the diaphragm. In the above technique, a through electrode substrate is used as the detection electrode.

Japanese Unexamined Patent Publication No. 2009-258088

In the above-mentioned mechanical quantity sensor, the pressure inside the sensor needs to be constant. That is, the inside of the dynamic quantity sensor needs to have high airtightness. However, depending on the shape of the through electrode or the manufacturing method, the airtightness between the through electrode and the substrate in the through electrode substrate may not be sufficient, and the dynamic quantity sensor may not normally perform its function. Examples of the dynamic quantity sensor include an acceleration sensor, an angular velocity sensor (gyro, yaw rate), a pressure sensor, an odor sensor, a CMOS / CCD image sensor, and the like, all of which require high airtightness.

In view of these issues, an object of the embodiments of the present disclosure is to provide a through silicon via substrate with high airtightness.

According to one embodiment of the present disclosure, a substrate having a first surface, a second surface on the opposite side of the first surface, and a through hole, a through electrode filled in the through hole, and a side surface and a through hole of the through electrode. The slit arranged between the side wall and the first surface side of the substrate covers the end and the slit of the through electrode, contacts a part of the upper surface of the through electrode and the first surface of the substrate, and is on the through electrode. On the through electrode, the first inorganic material having one perforation, the end of the through electrode and the slit on the second surface side of the substrate are covered, and a part of the upper surface of the through electrode and the second surface of the substrate are in contact with each other. A through electrode substrate comprising a second inorganic material having a second perforation is provided.

In the through electrode substrate, the inorganic material is characterized in that it is in contact with the side wall of the through hole.

Further, in the through electrode substrate, the upper surface of the through electrode has a dish-shaped concave shape.

According to one embodiment of the present disclosure, a substrate having a first surface, a second surface opposite the first surface and a through hole, and a first surface, a second surface of the substrate, and a side wall of the through hole are provided. On the first surface side of the base layer, the through electrode provided on the base layer, and the through hole, the boundary between the through electrode and the base layer is covered, and the upper surface of the through electrode and the first surface of the substrate are in contact with each other. , A through silicon via substrate comprising a first inorganic material having a perforation on the through electrode.

The through silicon via substrate is characterized in that the hole diameter of the through hole is 1 time or more and 4 times or less with respect to the thickness of the first inorganic material.

Further, in the through electrode substrate, the first inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order, and the thickness of the second inorganic film is that of the first inorganic film. It is characterized in that it is 1 times or more and 30 times or less the thickness.

Further, in the through silicon via substrate, the first inorganic film is a silicon nitride film, and the second inorganic film is a silicon oxide film.

Further, in the through silicon via substrate, the first inorganic material is a sintered body.

Further, the through silicon via substrate is characterized by further including a filler provided in the through hole and in contact with the through electrode on the side surface.

Further, the through electrode substrate further includes a first surface of the substrate, an upper surface of the through electrode on the first surface side, and a conductive layer in contact with the first inorganic material.

According to one embodiment of the present disclosure, a base layer is formed on the first surface of the substrate, the second surface on the opposite side of the first surface, and the side wall of the through hole, and the through electrode is formed so as to be in contact with the base layer. On the first surface side of the substrate, the boundary between the through electrode and the base layer and the through hole are covered, an inorganic material is formed so as to be in contact with the upper surface of the through electrode and the base layer, and the inorganic material is opened on the through electrode. A method of manufacturing a through silicon via substrate, including forming a hole, is provided.

In the method for manufacturing a through electrode substrate, the hole diameter of the through hole is 1 to 4 times or less with respect to the thickness of the inorganic material.

Further, in the method for manufacturing the through electrode substrate, the inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order, and the thickness of the second inorganic film is the first inorganic film. It is characterized in that it is 1 times or more and 30 times or less the thickness of.

Further, in the method for manufacturing a through silicon via substrate, the first inorganic film of the inorganic material is a silicon nitride film, and the second inorganic film of the inorganic material is a silicon oxide film.

Further, in the method for manufacturing a through electrode substrate, the inorganic material is characterized by being formed by a plasma CVD method.

Further, the method for manufacturing a through electrode substrate is characterized in that a filler is formed so as to be in contact with the side surface of the through electrode.

Further, the method for manufacturing a through electrode substrate is characterized in that a filler is formed so as to be in contact with the side surface of the through electrode in the through hole.

Further, in the method for manufacturing the through silicon via substrate, the base layer is formed by a dipping method.

According to one embodiment of the present disclosure, a mechanical quantity sensor including the through silicon via substrate is provided.

According to one embodiment of the present disclosure, it is possible to provide a through electrode substrate having a through electrode having high airtightness.

It is sectional drawing explaining the dynamic quantity sensor which concerns on one Embodiment of this disclosure. It is a top view and the cross-sectional view explaining the through silicon via substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is a top view and the cross-sectional view explaining the through silicon via substrate which concerns on one Embodiment of this disclosure. It is a top view and the cross-sectional view explaining the through silicon via substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the manufacturing method of the through electrode substrate which concerns on one Embodiment of this disclosure. It is sectional drawing explaining the through electrode substrate which concerns on one Embodiment of this disclosure.

Hereinafter, the through silicon via substrate, the dynamic quantity sensor, and the like according to each embodiment of the present disclosure will be described in detail with reference to the drawings. It should be noted that each of the embodiments shown below is an example of the embodiments of the present disclosure, and the present disclosure is not construed as being limited to these embodiments. In the drawings referred to in the present embodiment, the same parts or parts having similar functions are designated by the same reference numerals or similar reference numerals (reference numerals that are simply added with xxx-1, xxx-2, etc.). The repeated description may be omitted. In addition, the dimensional ratio of the drawing may differ from the actual ratio for convenience of explanation, or a part of the configuration may be omitted from the drawing.

In addition, in this specification, words and phrases indicating arrangements such as "above" and "below" are used for convenience in order to explain the positional relationship between configurations with reference to the drawings. Further, the positional relationship between the configurations changes as appropriate according to the direction in which each configuration is depicted. Therefore, it is not limited to the words and phrases explained in the specification, and can be appropriately paraphrased according to the situation.

<First Embodiment>
(1-1. Configuration of dynamic quantity sensor)
FIG. 1 shows a cross-sectional view of the dynamic quantity sensor 10. As shown in FIG. 1, the mechanical quantity sensor 10 has a through electrode substrate 100, a substrate 210, an insulating layer 220, a conductive layer 230, and a thin film 235.

A silicon substrate is used for the substrate 210. Silicon oxide, silicon nitride, hafnium oxide, aluminum oxide and the like are used for the insulating layer 220. A semiconductor material is used for the conductive layer 230, but a metal material or the like may be used. For example, when silicon (Si) is used for the conductive layer 230, a large amount of boron (B), aluminum (Al), phosphorus (P), arsenic (As), etc. are contained in the silicon (for example, 10 ¹⁸ to 10 ²⁰ atoms / cm). ^{By including (about 3} ), it can have conductivity. The substrate 210 and the insulating layer 220 have an opening portion 215.

The thin film 235 is provided as a portion corresponding to the region 250 of the conductive layer 230. The film thickness of the thin film 235 may be appropriately set, and is preferably 1 μm or more and 100 μm or less. The thin film 235 has flexibility. The thin film 235 has conductivity at least on the first surface 235A (upper surface).

The dynamic quantity sensor 10 has a closed space 300, and the shape of the thin film 235 changes according to an external force (for example, pressure). For example, when the external force is large, the thin film 235 flexes greatly to the lower side (first surface 235A side). Further, when the external force is small, the thin film 235 is less bent toward the lower side (first surface 235A side). The distance between the thin film 235 and the electrode 140 provided on the through electrode substrate 100 changes due to the difference in the shape change of the thin film 235. As a result, the capacitance between the thin film 235 and the electrode 140 changes, so that this is regarded as an electric signal, and an electric signal corresponding to the external force can be obtained. The configuration of the through silicon via substrate 100 will be described in detail below.

(1-2. Structure of through silicon via substrate)
FIG. 2A is a top view of the through silicon via substrate 100 between A1 and A2, and FIG. 2B is a cross-sectional view of the through silicon via substrate 100 between A1 and A2. As shown in FIG. 2B, the through electrode substrate 100 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130, an electrode 140, an inorganic material 150, and an electrode 160.

The substrate 110 has a first surface 110A and a second surface 110B opposite to the first surface 110A. Further, the substrate 110 is provided with a through hole 115. As shown in FIG. 2B, the through hole 115 when viewed from the upper surface may have a circular shape. The hole diameter of the through hole 115 may be appropriately set, but it is preferably set in the range of 10 μm or more and 100 μm or less.

A high resistance material is used for the substrate 110. For example, as the substrate 110, a glass substrate such as a quartz glass substrate, a soda glass substrate, a borosilicate glass substrate, or a non-alkali glass substrate is used. The plate thickness of the substrate 110 may be appropriately set, preferably in the range of 200 μm or more and 700 μm or less.

The substrate 110 is not limited to a glass substrate, but is a sapphire substrate, a silicon substrate, a silicon carbide substrate, an alumina (Al ₂ O ₃ ) substrate, an aluminum nitride (AlN) substrate, a zirconia (ZrO ₂ ) substrate, acrylic or polycarbonate, or the like. A resin substrate containing the above-mentioned materials, or one in which these substrates are laminated may be used.

The through electrode 120 is filled in the through hole 115. A low resistance material is used for the through electrode 120. For example, copper (Cu) is used for the through electrode 120. In addition, the present invention is not limited to this, and a material containing gold (Au), silver (Ag), nickel (Ni) or tin (Sn) may be used.

A slit 125 is provided between the side surface 120E of the through electrode 120 and the side wall 115A of the through hole 115. Gas generated during the formation of the through electrode substrate may stay in the slit 125.

The non-equipment 130 is provided in contact with a part of the first surface 110A of the substrate 110 and the upper surface 120A of the through electrode 120. At this time, the inorganic material 130 covers the end 120C and the slit 125 of the through electrode 120, as shown in FIGS. 2 (A) and 2 (B). As a result, the movement of a fluid such as gas existing between the through electrode 120 and the substrate 110 can be suppressed.

Further, the inorganic material 130 may be in contact with the side wall 115A of the through hole 115 (that is, the inorganic material 130 may be provided in the slit 125). As a result, stress distribution at the end 120C of the through silicon via 120 can be achieved. Further, the inorganic material 130 has an opening portion 135 on the upper surface 120A of the through electrode 120.

Further, the side surface 130A of the inorganic material 130 may have a tapered shape. As a result, even if the film thickness of the inorganic material 130 is large, the electrode 140 can be prevented from being broken.

An inorganic insulating material is used for the non-equipment 130. For example, as the inorganic material 130, a single film or a laminated film such as a silicon oxide film, a silicon nitride film, a silicon nitride film, or an aluminum oxide film is used. A silicon nitride film is desirable because of its high density. Further, the inorganic material 130 can be made into a laminated film to improve the airtightness. The inorganic material 130 is not limited to the above, and an inorganic resin material may be used.

The hole diameter of the through hole 115 may be appropriately set between the inorganic material 130 and the through hole 115, but it is preferably 1 time or more and 4 times or less the thickness of the inorganic material 130. .. As a result, the inorganic material can have a sufficient thickness and can have sufficient airtightness with respect to the gas staying in the slit 125.

The electrode 140 is in contact with the first surface 110A of the substrate 110, the upper surface 120A of the through electrode 120, and the inorganic material 130. The electrode 140 does not necessarily have to be in contact with the first surface 110A of the substrate 110.

The non-equipment 150 is provided in contact with the second surface 110B of the substrate 110 and a part of the upper surface 120B of the through electrode 120. Further, the inorganic material 150 covers the end 120D of the through electrode 120 and the slit 125 in the same manner as the inorganic material 130. Further, the inorganic material 150 has an opening portion 155 on the upper surface 120B of the through electrode 120. (In FIG. 2, the slit 125 is shown large in the drawing in order to make it easy to understand.)

The electrode 160 is in contact with the upper surface 120B of the through electrode 120 and the inorganic material 150. The electrode 160 may be in contact with the second surface 110B of the substrate 110.

(1-3. Manufacturing method of through silicon via substrate)
Next, the manufacturing method of the through silicon via substrate 100 shown in FIG. 2 will be described with reference to FIGS. 3 to 8.

First, as shown in FIG. 3, a substrate 110 having a first surface 110A and a second surface 110B opposite to the first surface 110A is used. For example, a soda glass substrate, a non-alkali glass substrate, or a silicon substrate is used as the substrate 110.

Next, as shown in FIG. 4, a through hole 115 is formed in the substrate 110. The through hole 115 is formed, for example, by using a laser irradiation method (which can be called a laser ablation method) on the substrate 110. As the laser, an excimer laser, a neodymium: YAG laser (Nd: YAG) laser, a femtosecond laser, or the like is used. When an excimer laser is used, light in the ultraviolet region is irradiated. For example, when xenon chloride is used in an excimer laser, light having a wavelength of 308 nm is irradiated. The hole diameter of the through hole 115 may be appropriately set by controlling the laser irradiation, but is preferably in the range of 10 μm or more and 100 μm or less. By using the above method, the through hole 115 has a circular shape when viewed from the upper surface. Further, a plurality of through holes 115 may be provided.

The formation of the through hole 115 is not limited to the laser irradiation method, and a dry etching method such as a reactive ion etching method or a deep digging reactive ion etching method, a wet etching method, or a laser irradiation method may be used. And the wet etching method may be used in combination. As the etching solution for the wet etching method, _{any one of hydrofluoric acid (HF), nitric acid (HNO 3} ) and an alkaline solution may be used. For example, when wet etching a glass substrate, hydrofluoric acid is used. When etching a silicon substrate, an alkaline solution or nitric acid and hydrofluoric acid are used. The through hole 115 may have a rectangular shape or a tapered shape in a cross-sectional view.

Next, as shown in FIG. 5, a through electrode 120 is formed in the through hole 115. In addition to copper (Cu), nickel (Ni), gold (Au), silver (Ag), tin (Sn) and the like are used for the through electrode 120.

The through electrode 120 is formed by the following method. First, a thin film of copper (Cu) is formed on the second surface 110B of the substrate 110 by a sputtering method. Next, a copper (Cu) film is formed by an electrolytic plating method using a thin film of copper (Cu) as a seed layer. At this time, since the copper (Cu) film grows not only in the epitaxial direction but also in the lateral direction, the bottom portion 115B (see FIG. 4) of the through hole 115 is covered. (This film may be referred to as a lid plating film 117. See FIG. 5).

Next, as shown in FIG. 6, a through electrode 120 is formed by filling and forming a copper (Cu) film in the through hole 115 by an electrolytic plating method using the lid plating film 117 as a seed layer. Finally, the portion of the upper surface 120A of the through electrode 120 exposed from the first surface 110A of the substrate 110 and the lid plating film 117 are removed by a chemical mechanical polishing (CMP) method.

At the stage of forming the through electrode 120, the adhesion between the substrate 110 and the through electrode 120 is small. Therefore, for example, when heat treatment is performed, a slit 125 is formed between the end portion 120C of the through electrode 120 and the side wall 115A of the through hole 115 due to a difference in the coefficient of thermal expansion, a change in stress, and the like. (In FIG. 6, the slit 125 is shown in large size for easy understanding.)

Next, as shown in FIG. 7, the inorganic material 130 is formed. The non-equipment 130 is formed by a CVD (Chemical Vapor Deposition) method, a sputtering method, or a vapor deposition method. For example, as the inorganic material 130, a single film or a laminated film of an inorganic film such as silicon oxide or silicon nitride formed is used.

An organic-inorganic hybrid resin containing silica may be used as the inorganic material 130. Further, the inorganic material 130 is processed into a predetermined shape by combining a photolithography method, an etching method, and the like. At this time, the opening portion 135 is formed on the through electrode 120 with respect to the inorganic material 130. The inorganic material 130 covers a part of the first surface 110A of the substrate 110 by processing. Thereby, the stress concentration of the inorganic material 130 can be relaxed.

The hole diameter of the through hole 115 may be appropriately set between the inorganic material 130 and the through hole 115, but it is preferably 1 time or more and 4 times or less the thickness of the inorganic material 130. .. As a result, the inorganic material can have a sufficient thickness and can have sufficient airtightness with respect to the gas staying in the slit 125. The non-equipment 130 may be formed so as to have a tapered shape on the side surface. This makes it possible to prevent disconnection when forming the electrode 140 thereafter.

Next, as shown in FIG. 8, 140 is formed on the first surface 110A of the substrate 110, the upper surface 120A of the through electrode 120, and the insulating layer 140. The electrode 140 is formed by using a plating method, a sputtering method, a vapor deposition method, a printing method, an etching method, or the like. For the electrode 140, copper (Cu) nickel (Ni), gold (Au), silver (Ag), tin (Sn), aluminum (Al), tungsten (W), titanium (Ti) or molybdenum (Mo) is used. .. For example, as the electrode 140, a copper (Cu) film formed by a plating method is used.

Next, the inorganic material 150 and the electrode 160 are formed on the second surface 110B of the substrate 110. The non-equipment 150 is formed in the same manner as the inorganic material 130. The electrode 160 is formed in the same manner as the electrode 140. The through electrode substrate 100 is manufactured by the above method.

Since the through silicon via substrate 100 is manufactured by the above-mentioned structure and method, it can have high airtightness even if gas is retained in the slit 125. Therefore, the pressure in the space 300 inside the dynamic quantity sensor 10 shown in FIG. 1 can be kept constant. Therefore, the mechanical quantity sensor using the through silicon via substrate 100 can stably exert its function. Further, the through electrode 120, the inorganic material 130, and the substrate 110 are arranged in this order at the end of the through hole 115. As a result, the stress applied to the vicinity of the end of the through hole 115 of the inorganic material 130 during the formation of the through electrode substrate (particularly during heat treatment) is dispersed, and defects (cracks) in the inorganic material 130 or film peeling of the inorganic material 130 are prevented. Will be done.

FIG. 9A is a top view of the through silicon via substrate 100-1 between A1 and A2, and FIG. 9B is a cross-sectional view of the through silicon via substrate 100-1 between A1 and A2.

In FIG. 9B, of the through electrodes 120, the upper surface 120A-1 on the first surface 110A side and the upper surface 120B-1 on the second surface 110B side of the substrate 110 each have a dish-shaped concave shape. This shape is due to the dishing that occurs when the through electrode 120 is polished with a metal film (for example, a copper (Cu) film) by the CMP method. At this time, as a result of applying strong pressure to the through electrode 120, the width of the slit 125-1 may be larger than the width of the slit 125 of the through electrode substrate 100. In such a case, the flow of gas may be facilitated. However, since the through electrode substrate 100-1 has the inorganic material 130 and the inorganic material 150, the end 120C of the through electrode 120 and the slit 125-1 can be sufficiently covered. Therefore, the through silicon via substrate 100-1 can have a high airtightness and further effect. Therefore, since the pressure in the space 300 inside the dynamic quantity sensor 10 can be made constant, the function of the dynamic quantity sensor 10 can be stably exhibited.

<Second Embodiment>
(2-1. Structure of through silicon via substrate)
Next, a through electrode substrate having a different structure will be described. The description of the structure, material and method shown in the first embodiment will be incorporated.

FIG. 10A shows a top view of the through silicon via substrate 100-2 between A1 and A2. FIG. 10B shows a cross-sectional view of the through silicon via substrate 100-2 between A1 and A2.

As shown in FIG. 10B, the through electrode substrate 100 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130-2, an electrode 140, an inorganic material 150-2, and an electrode 160.

In the through electrode substrate 100-2, a slit may not be completely provided or may be provided slightly between the side surface 120E of the through electrode 120 and the side wall 115A of the through hole 115 (in FIG. 2B). Described as slit 125-2). Even in this case, the gas at the time of formation may stay.

The non-equipment 130-2 is provided in contact with the first surface 110A of the substrate 110 and the upper surface 120A of the through electrode 120. At this time, the inorganic material 130-2 covers the end 120C (and the slit 125-2) of the through electrode 120.

An inorganic insulating material is used for the non-equipment 130-2. In this example, as the inorganic material 130, a film in which an inorganic film 131 and an inorganic film 133 are laminated is used. At this time, a silicon nitride film is used for the inorganic film 131. A silicon oxide film is used as the inorganic film 133. At this time, it is desirable that the thickness of the inorganic film 133 is 1 time or more and 30 times or less, more preferably 2 times or more and 20 times or less the thickness of the inorganic film 131. This is because the stress of the silicon nitride film is larger than the stress of the silicon oxide film.

The silicon nitride film used for the inorganic film 131 is _{formed by a plasma CVD method using SiH 4} gas, NH ₃ gas, or the like. Silicon oxide film used in the inorganic film 133 may be formed by using a SiH ₄ gas and _{N 2} O gas by a plasma CVD method.

The non-equipment 150-2 is provided in contact with the second surface 110B of the substrate 110 and the upper surface 120B of the through electrode 120. Further, the inorganic material 150-2 covers the end 120D of the through electrode 120 and the slit 125 in the same manner as the inorganic material 130.

An inorganic insulating material is used for the non-equipment 150-2. In this example, as the inorganic material 150-2, a film in which an inorganic film 151 and an inorganic film 153 are laminated is used as in the case of the inorganic material 130-2. At this time, a silicon nitride film is used for the inorganic film 151. A silicon oxide film is used as the inorganic film 153.

Since the silicon nitride film used as the inorganic film 131 and the inorganic film 151 has high density, the flow of gas is prevented. That is, the airtightness of the through electrode can be improved.

On the other hand, especially when in contact with or close to the substrate 110, stress is applied to the end 120C and the end 120D of the through electrode 120 due to the difference between the coefficient of thermal expansion of the substrate 110 and the coefficient of thermal expansion of the through electrode 120. It is easy to concentrate, and the inorganic material 130 and the inorganic material 150 may be damaged. At this time, as shown in FIG. 10B, since the inorganic material 130 and the inorganic material 150 are laminated films, stress relaxation (control) can be performed. As a result, damage to the inorganic material 130 and the inorganic material 150 is prevented while ensuring airtightness.

<Third Embodiment>
(3-1. Structure of through silicon via substrate)
Next, the through silicon via substrates 100-3 having different structures will be described. The explanations of the structures, materials and methods shown in the first embodiment and the second embodiment will be appropriately incorporated.

FIG. 11 is a cross-sectional view between A1 and A2 of the through silicon via substrate 100-3. As shown in FIG. 11, the through electrode substrate 100-3 includes a substrate 110, a through hole 115, a through electrode 121, and an inorganic material 130-3.

The base layer 113 is provided on the first surface 110A and the second surface 110B of the substrate 110 and the side wall 115A of the through hole 115. The base layer 113 contains a metal oxide. For example, zinc oxide is used as the metal oxide. The base layer 113 has a function of improving the adhesion between the substrate 110 and the third electrode 140.

The through electrode 121 is provided on the base layer 113. Through electrodes 121 include a seed layer 122.

The non-equipment 130-3 is provided in contact with the base layer 113A on the first surface 110A side of the substrate 110 and the upper surface 121A of the through electrode 121. At this time, the inorganic material 130 covers the through hole 115 and the boundary portion 121E between the through electrode 121 and the base layer 113.

The hole diameter of the through hole 115 may be appropriately set between the inorganic material 130-3 and the through hole 115, but is preferably 1 to 4 times the thickness of the inorganic material 130-3. Is desirable. At this time, the inorganic material 130-3 has a sufficient thickness to cover the boundary portion 121E between the through electrode 121 and the base layer 113.

When the film thickness of the non-equipment 130-3 is large, the inorganic material 130-3 can cover the through hole 115 as described above on the first surface 110A side of the substrate 110. Further, the inorganic material 130-3 has an opening portion 135 on the upper surface 120A of the through electrode 120.

An inorganic insulating material is used for the non-equipment 130-3. In this example, as the inorganic material 130-3, a film in which an inorganic film 131 and an inorganic film 133 are laminated in this order is used. At this time, a silicon nitride film is used for the inorganic film 131. A silicon oxide film is used as the inorganic film 133. At this time, it is desirable that the thickness of the inorganic film 133 is 1 time or more and 30 times or less, preferably 2 times or more and 20 times or less the thickness of the inorganic film 131.

With the above structure, the movement of a fluid such as a gas existing between the through electrode 121 and the substrate 110 can be suppressed, and the pressure inside the dynamic quantity sensor 10 can be kept constant.

(3-2. Manufacturing method of through silicon via substrate)
Next, the manufacturing method of the through electrode substrate 100-3 is shown in FIGS. 12 to 17.

First, as shown in FIG. 12, the base layer 113 is formed on the side wall of the through hole 115, the first surface 110A and the second surface 110B of the substrate 110. The base layer 113 is formed by a dipping method. The base layer 113 contains a metal oxide. For example, zinc oxide is used as the metal oxide. Specifically, the base layer 113 is formed by immersing the substrate 110 in a solution containing zinc acetate dihydrate. After forming the base layer 113, heat treatment may be performed.

Next, as shown in FIG. 13, the seed layer 122 is formed on the first surface 110A, the second surface 110B, and the through hole 115 of the substrate 110. The seed layer 122 is formed by a electroless plating method. The seed layer 122 contains copper (Cu). In addition, nickel (Ni) or gold (Au) may be used for the seed layer 122 as a material other than copper.

The electroless plating method will be described below. When electroless plating is performed, a conditioner, an activator, a metal salt, a reducing agent, a complexing agent and the like are used. Conditioner is used as a pretreatment agent. The conditioner is used to facilitate the adhesion of the Pd catalyst to the surface of the base layer 113. Activators are used to form Pd catalysts on the surface. The metal salt is a material for precipitating a metal. For example, when copper plating is performed, copper sulfate is used. Reducing agents are used to reduce metal salts. As the reducing agent, dimethylaminoborane (DMAB), formaldehyde, hydrazine hydrochloride, hydrazine sulfate and the like are used. The complexing agent is used to control the precipitation rate of the metal film. As the complexing agent, ethylenediaminetetraacetic acid (EDTA), Rochelle salt (L-potassium sodium tartrate tetrahydrate), citrate ion and the like are used. Moreover, you may perform degreasing treatment before performing electroless plating. Further, the heat treatment may be performed after the electroless plating treatment.

Next, as shown in FIG. 14, a resist film 127 is formed on the seed layer 122. As the resist film 127, one formed by coating may be used, or a dry film resist may be used. The resist film 127 is processed into a predetermined shape by a photolithography method.

Next, as shown in FIG. 15, a through electrode 121 is formed on the exposed seed layer 125. The through electrode 121 is formed by an electrolytic plating method. The through silicon via 121 is conformally plated. A copper (Cu) film is used for the through electrode 121. The method for forming the through electrode is called a semi-additive method. After forming the through electrode 121, the resist film 127 is removed. The resist film 127 may be removed by a chemical solution or by a dry etching method.

Next, as shown in FIG. 16, the seed layer 122 provided under the resist film 127 is removed. At this time, the seed layer 122 is removed by a wet etching method. The above method is called a semi-additive method. By using the above method, the through electrode 121 can be formed thick.

Next, as shown in FIG. 17, the inorganic material 130 is formed so as to be in contact with the base layer 113 and the upper surface 121A of the through electrode 121 on the first surface 110A side of the substrate 110. At this time, the inorganic material 130 covers the through hole 115 and the boundary portion 121E between the through electrode 121 and the base layer 113.

An inorganic insulating material is used for the non-equipment 130-3. In this example, a film obtained by laminating an inorganic film 131 and an inorganic film 133 is used as the inorganic material 130-3. A silicon nitride film is used for the inorganic film 131. A silicon oxide film is used as the inorganic film 133. At this time, it is desirable that the thickness of the inorganic film 133 is 1 time or more and 30 times or less, more preferably 2 times or more and 20 times or less the thickness of the inorganic film 131. This is because the stress of the silicon nitride film is larger than the stress of the silicon oxide film.

The non-equipment 130-3 is formed by the plasma CVD method in this example. The silicon nitride film used for the inorganic film 131 is formed by using _{SiH 4} gas and NH _{3 gas.} The silicon oxide film used for the inorganic film 133 is formed by using _{SiH 4} gas and N _{2 O gas.} The inorganic film 131 and the inorganic film 133 may be formed by a sputtering method, a vapor deposition method, or a printing method.

The hole diameter of the through hole 115 may be appropriately set between the inorganic material 130-3 and the through hole 115, but is preferably 1 to 4 times or less with respect to the thickness of the inorganic material 130-3. Is desirable. At this time, the inorganic material 130-3 has a sufficient thickness. As a result, the inorganic material 130-3 grows not only in the epitaxial direction but also in the lateral direction on the first surface 110A side of the substrate 110 described above. Thereby, the inorganic material 130-3 can cover the through hole 115.

The non-equipment 130-3 is processed into a predetermined shape by combining a photolithography method and an etching method. At this time, an opening portion 135 is formed on the through electrode 121 with respect to the inorganic material 130-3.

By the above method, the through silicon via substrate 100-3 shown in FIG. 11 is manufactured.

In the through electrode substrate 100-3 manufactured by the above method, a heat treatment is performed between the base layer 113 and the through electrode 121 (particularly between the base layer 113 and the seed layer 122) to obtain a metal. There may be a difference in the coefficient of thermal expansion with the metal oxide. As a result, strain (stress concentration) may occur, and the adhesion between the through electrode and the base layer may not be sufficient. (For example, one may be tensile stress and the other may be compressive stress.) Therefore, a gap is generated at the boundary (interface) between the base layer 113 and the through electrode 121, and a fluid such as gas is released. It may be movable. However, the silicon nitride film used as the inorganic film 131 of the inorganic materials 130-3 provided on the through silicon via substrate 100-3 has high density. Further, the inorganic material 130-3 has a sufficiently large thickness. Therefore, the flow of gas at the boundary (interface) between the base layer 113 and the through electrode 121 is prevented.

Further, the through hole 115 is completely covered with the inorganic material 130-3. That is, by having the inorganic material 130-3, the airtightness of the through electrode substrate can be improved.

Since the inorganic material 130 is a laminated film, stress can be relaxed (controlled). For example, the silicon nitride film of the inorganic film 131 is given a tensile stress, and the silicon oxide film is given a compressive stress. By controlling the stress in this way, the occurrence of defects (cracks, film peeling, etc.) in the inorganic material 130-3 is suppressed.

<Fourth Embodiment>
(4-1. Structure of through silicon via substrate)
Next, the through silicon via substrates 100-4 having different structures will be described. The explanations of the structures, materials and methods shown in the first to third embodiments will be appropriately incorporated.

FIG. 18 is a cross-sectional view between A1 and A2 of the through silicon via substrate 100-4. As shown in FIG. 18, the through electrode substrate 100-4 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130, and a filler 170.

The filler 170 is provided in the through hole 115. Further, the filler 170 is in contact with the side surface of the through electrode 120. The filler 170 contains an inorganic resin material. Further, the filler 170 may contain inorganic particles. Inorganic particles have a size of, for example, several tens of nm or more and several tens of μm or less. The inorganic particles include silica, alumina and the like.

The filler 170 is filled and formed in the through hole 115 so as to be in contact with the side surface of the through electrode 121. The filler 170 is formed by a sol-gel method, an inkjet method, or a dipping method. After forming the filler 170, heat treatment may be appropriately performed. As a result, the filler can be made more dense.

(Modification example 1)
In the third embodiment, an example in which a laminated film of a silicon nitride film and a silicon oxide film is used for the inorganic material 130-3 is shown, but the present invention is not limited to this. A sintered body may be used for the non-equipment 130-3. For example, an inorganic sintered body (ceramics) may be used as the sintered body.

(Modification 2)
In the first embodiment, an example in which the upper surface of the through electrode 120 has a concave shape is shown, but the present invention is not limited to this. For example, a substrate having a bottomed shape (sometimes referred to as a hole glass substrate) is filled and plated, and the substrate is exposed from the non-bottomed surface side (second surface side) until the filled-plated metal material is exposed. The through electrode 120 may be formed by polishing. In that case, the hole shape of the bottomed structure is not a rectangular structure but a pointed shape. Then, the filling plating shape also becomes a pointed (convex shape) shape. At this time, the upper surface of the through electrode may have a convex shape.

10 ... Mechanical quantity sensor, 100 ... Through electrode substrate, 110 ... Substrate, 113 ... Underlayer, 115 ... Through hole, 117 ... Lid plating film, 120 ... Through electrode , 121 ... through electrode, 122 ... seed layer, 125 ... slit, 127 ... resist film, 130 ... inorganic material, 131 ... inorganic film, 133 ... inorganic film, 135 ... Opening part, 140 ... Electrode, 150 ... Inorganic material, 151 ... Inorganic film, 153 ... Inorganic film, 155 ... Opening part, 160 ... Electrode, 170. .. Filler, 210 ... Substrate, 215 ... Perforated part, 220 ... Insulation layer, 230 ... Conductive layer, 235 ... Thin film, 250 ... Region, 300 ... Space

Claims (17)

A substrate having a first surface, a second surface opposite to the first surface, and a through hole,
Through electrodes filled in the through holes and
A first slit arranged between the side surface of the through electrode on the first surface side and the side wall of the through hole on the first surface side.
A second slit arranged between the side surface of the through electrode on the second surface side and the side wall of the through hole on the second surface side.
On the first surface side of the substrate, the end portion of the through electrode and the first slit are covered, and a part of the upper surface of the through electrode and the first surface of the substrate are in contact with each other, and the first surface is placed on the through electrode. A first inorganic material having a perforated portion and
On the second surface side of the substrate, the end portion of the through electrode and the second slit are covered, and a part of the upper surface of the through electrode and the second surface of the substrate are in contact with each other, and the second surface is placed on the through electrode. and a second inorganic material having an opening, only including,
The first inorganic material and the second inorganic material are films in which a first inorganic film and a second inorganic film are laminated in this order.
The first inorganic film is a silicon nitride film, and the first inorganic film is a silicon nitride film.
The second inorganic film is a silicon oxide film, and is
The thickness of the second inorganic film is larger than the thickness of the first inorganic film.
Through electrode substrate. The first inorganic material and the second inorganic material are in contact with the side wall of the through hole.
The through silicon via substrate according to claim 1. The upper surface of the through electrode has a dish-shaped concave shape.
The through silicon via substrate according to claim 1 or 2. A substrate having a first surface, a second surface opposite to the first surface, and a through hole,
The base layer provided on the first surface, the second surface, and the side wall of the through hole of the substrate, and
Through electrodes provided on the base layer and
On the first surface side of the substrate, the through hole and the boundary between the through electrode and the base layer are covered, and the upper surface of the through electrode and the first surface of the substrate are in contact with each other, and a hole is opened on the through electrode. a first inorganic material with, only including,
The first inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order.
The first inorganic film is a silicon nitride film, and the first inorganic film is a silicon nitride film.
The second inorganic film is a silicon oxide film, and is
The thickness of the second inorganic film is larger than the thickness of the first inorganic film.
Through electrode substrate. The hole diameter of the through hole is 1 to 4 times or less with respect to the thickness of the first inorganic material.
The through silicon via substrate according to claim 4. The thickness of the second inorganic film is 2 times or more and 30 times or less the thickness of the first inorganic film.
The through silicon via substrate according to any one of claims 1 to 5. The first inorganic material is a sintered body.
The through silicon via substrate according to claim 4. Further includes a filler provided in the through hole and in contact with the through electrode on the side surface.
The through silicon via substrate according to any one of claims 4 to 7. The first surface of the substrate, the upper surface of the through electrode on the first surface side, and the conductive layer in contact with the first inorganic material are further included.
The through silicon via substrate according to any one of claims 1 to 7. A base layer is formed on the first surface of the substrate, the second surface on the opposite side of the first surface, and the side wall of the through hole.
A through electrode is formed so as to be in contact with the base layer.
In the first surface side of the substrate, covering the boundary between the base layer and the through-hole and the through-electrode, forms a inorganic in contact with the upper surface and the underlying layer of the through electrode,
To form an opening on the through electrode with respect to the inorganic material.
Only including,
The inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order.
The first inorganic film is a silicon nitride film, and the first inorganic film is a silicon nitride film.
The second inorganic film is a silicon oxide film, and is
The thickness of the second inorganic film is larger than the thickness of the first inorganic film.
Manufacturing method of through silicon via substrate. The hole diameter of the through hole is 1 to 4 times or less with respect to the thickness of the inorganic material.
The method for manufacturing a through silicon via substrate according to claim 10. The thickness of the second inorganic film is 2 times or more and 20 times or less the thickness of the first inorganic film.
The method for manufacturing a through silicon via substrate according to claim 11. The inorganic material is formed by a plasma CVD method.
The method for manufacturing a through silicon via substrate according to claim 10. The inorganic material is a sintered body.
The method for manufacturing a through silicon via substrate according to claim 10. In the through hole, including forming a filler so as to be in contact with the side surface of the through electrode.
The method for manufacturing a through silicon via substrate according to any one of claims 10 to 14. The base layer is formed by a dipping method.
The method for manufacturing a through silicon via substrate according to any one of claims 10 to 15. The through silicon via substrate according to any one of claims 1 to 9 is included.
Mechanics sensor.

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