JP6606933B2 - Substrate manufacturing method and droplet discharge head manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a substrate and a method for manufacturing a droplet discharge head.

  In general, printers, facsimiles, copiers, plotters, or image forming apparatuses that combine a plurality of these functions include, for example, an ink jet recording apparatus that includes a droplet discharge head that discharges droplets of ink or the like.

  The droplet discharge head is a nozzle hole that discharges a liquid droplet of ink or the like and a liquid chamber (pressure chamber, pressure chamber, pressurization chamber, discharge chamber, etc.) that communicates with the nozzle hole and contains liquid. And an electromechanical transducer such as a piezoelectric element are known. In this droplet discharge head, when a voltage is applied to the piezoelectric element, the piezoelectric element vibrates so as to deform a diaphragm that forms part of the wall of the liquid chamber, and the liquid in the liquid chamber is deformed by the deformation of the diaphragm. Is pressurized and droplets can be ejected from the nozzle holes.

  As a droplet discharge head, a substrate bonded to a substrate on which a pressurized liquid chamber is formed, and a substrate having a through hole that becomes a part of a flow path for supplying liquid from outside to the pressurized liquid chamber Those equipped with are widely used.

  It is known that the substrate in which the through hole is formed is made using a silicon substrate, and it has been known that the through hole (opening) is formed by applying anisotropic wet etching to the silicon substrate. It has been.

  However, for example, when a through-hole is formed by applying anisotropic wet etching using a silicon substrate having a surface orientation (110), a complicated process or dedicated equipment is required, and the design according to the surface orientation is required. The restrictions are large and it has been difficult to perform highly accurate dimensional control.

On the other hand, Patent Document 1 discloses that a through-hole is formed using a silicon substrate having a plane orientation (100) by using anisotropic wet etching and dry etching together. Similarly, Patent Document 2 also uses anisotropic wet etching and dry etching together,
It is disclosed to form a through hole.

  However, in the techniques of Patent Documents 1 and 2, the manufacturing process is complicated, and depending on the area and pattern of the opening, dimensional control and shape control may be difficult, and a highly accurate substrate may not be formed. It was.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a substrate capable of controlling dimensions and shapes easily and with high accuracy.

In order to achieve such an object, a substrate manufacturing method according to the present invention is a substrate manufacturing method used in a droplet discharge head, wherein a portion along the outer diameter of a portion in which a through hole is formed in the substrate is formed. and organic and groove forming step of forming a through hole forming a groove by penetrating into a groove shape by dry etching, and a removal step of removing the portion surrounded by the through hole forming a groove, in the groove forming step, said through The groove is passed through a portion surrounded by the hole forming groove .

  According to the present invention, it is possible to provide a method for manufacturing a substrate capable of controlling dimensions and shapes easily and with high accuracy.

FIG. 3 is a cross-sectional view of the liquid chamber in the arrangement direction showing a schematic configuration of a droplet discharge unit that is a main part of the droplet discharge head. It is sectional drawing of the direction orthogonal to the arrangement direction of a liquid chamber which shows schematic structure of a droplet discharge part. It is a perspective view which shows schematic structure of a droplet discharge part. It is a figure which shows the example of the XRD pattern figure of a SRO film | membrane (111). It is a top view of the sub-frame board | substrate with which the groove | channel and the hollow part were formed. It is a top view of the sub-frame board | substrate with which the through-hole was formed. It is a top view of a state where counterbore and through-hole forming grooves are formed on the subframe substrate. It is explanatory drawing of the 1st process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 2nd process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 3rd process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 4th process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 5th process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 6th process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 7th process of the manufacturing method of a sub-frame board | substrate. It is explanatory drawing of the 8th process of the manufacturing method of a sub-frame board | substrate. It is a top view of a state where counterbore and through-hole forming grooves are formed on the subframe substrate. FIG. 6 is a perspective view illustrating a configuration example of an ink cartridge including a droplet discharge head. It is a perspective view showing an example of composition of an ink jet recording device provided with a droplet discharge head. FIG. 4 is a side view illustrating a configuration example of a mechanism unit of an ink jet recording apparatus including a droplet discharge head.

  Hereinafter, the configuration according to the present invention will be described in detail based on the embodiment shown in FIGS.

  The substrate manufacturing method according to the present embodiment is a method for manufacturing a substrate (subframe substrate 30) used in a droplet discharge head (droplet discharge head 1), and a through hole (through hole 37) is formed in the substrate. A groove forming step of forming a through hole forming groove (through hole forming groove 38) by passing a portion along the outer diameter shape of the portion to be formed into a groove shape by dry etching, and a portion surrounded by the through hole forming groove ( And a removal step of removing the hollowed portion 39). In addition, the code | symbol in embodiment and the example of application are shown in a parenthesis.

(Configuration of droplet discharge head)
FIG. 1 is a cross-sectional view in the arrangement direction of liquid chambers showing a schematic configuration of a droplet discharge section 10 which is a main part of the droplet discharge head 1, and only a portion corresponding to one liquid chamber is shown for convenience. FIG. 2 is a cross-sectional view showing a schematic configuration of the droplet discharge unit 10 in a direction orthogonal to the liquid chamber arrangement direction. FIG. 3 is a perspective view showing a schematic configuration of the droplet discharge unit 10.

  As shown in FIG. 1, the droplet discharge unit 10 includes a nozzle substrate 12 having a nozzle hole 11 for discharging a liquid droplet of ink or the like, and a pressurized liquid chamber 13 communicating with the nozzle hole 11 and containing a liquid. And an actuator substrate 14 formed. The actuator substrate 14 is formed with a partition portion of the pressurized liquid chamber 13 communicating with the nozzle hole 11, a fluid resistance portion 21, a common liquid chamber 22, and the like. On the actuator substrate 14, a vibration plate 15 that forms one wall surface of the pressurized liquid chamber 13 is formed, and a piezoelectric element 16 including a lower electrode 161, a piezoelectric body (PZT) 162, and an upper electrode 163 is provided on the vibration plate 15. It has been. A first insulating protective film 17, a second insulating protective film 18, a third insulating protective film 19, and a subframe substrate 30 are provided so as to cover the piezoelectric element 16. A drive IC 20 is also provided.

  The piezoelectric element 16 includes a lower electrode 161 serving as a common electrode on the diaphragm 15 side, a piezoelectric body 162 made of PZT or the like as an electromechanical conversion film, and an individual electrode on the opposite side of the piezoelectric body 162 from the diaphragm 15 side. The upper electrode 163 is laminated. The lower electrode 161 is connected to the wiring 31 by a contact hole 17a formed in the first insulating protective film 17, and is connected to a pad electrode for a common electrode as a terminal electrode for external connection through the wiring 31. Has been. The upper electrode 163 is connected to the wiring 32 through a contact hole 18a formed in the second insulating protective film 18, and a pad electrode for an individual electrode as a terminal electrode for external connection through the wiring 32. 33.

  The subframe substrate 30 is formed with a counterbore 34 as a protective space for the piezoelectric element 16 including a common electrode wiring 31 and an individual electrode wiring 32 electrically connected to the lower electrode 161 and the upper electrode 163. ing. In addition, a droplet supply port 35 for supplying droplets from the outside and a through hole serving as a common droplet channel 36 are formed. The common droplet channel 36 communicates with the common liquid chamber 22 from the droplet supply port 35.

  The droplet discharge section 10 is formed by joining the actuator substrate 14 provided with the nozzle substrate 12, the vibration plate 15, and the like and the subframe substrate 30.

  In the droplet discharge section 10 having the above-described configuration, it is desired to discharge ink from the drive IC 20 based on image data in a state where each pressurizing liquid chamber 13 is filled with liquid (for example, ink as recording liquid). For example, a pulse voltage of 20 V is applied to the upper electrode 163 corresponding to the nozzle hole 11 by an oscillation circuit.

  By applying this pulse voltage, the piezoelectric body 162 contracts in the direction parallel to the diaphragm 15 due to the electrostrictive effect, so that the diaphragm 15 bends in the direction of the pressurized liquid chamber 13. As a result, the pressure in the pressurizing liquid chamber 13 rapidly increases, and ink is ejected from the nozzle holes 11 communicating with the pressurizing liquid chamber 13. Next, since the contracted piezoelectric body 162 returns to the original position after the pulse voltage is applied, the deflected diaphragm 15 returns to the original position, so that the inside of the pressurized liquid chamber 13 is compared with the inside of the common liquid chamber 22. Ink supplied from the outside via the droplet supply port 35 is supplied from the common droplet flow path 36 and the common liquid chamber 22 to the pressurized liquid chamber 13 via the fluid resistance portion 21. By repeating this, ink can be ejected continuously, and an image is formed on a recording medium (paper) disposed facing the droplet ejection head 1.

  Next, the materials and construction methods of the respective parts and members, which are constituent elements constituting the droplet discharge head 1, will be described more specifically.

〔substrate〕
As the actuator substrate 14, it is preferable to use a silicon single crystal substrate, and it is preferable that the actuator substrate 14 usually has a thickness in a range of 100 [μm] to 600 [μm]. There are three types of plane orientations: (100), (110), and (111), but (100) and (111) are generally widely used in the semiconductor industry. In this configuration example, A single crystal substrate having a (100) plane orientation was mainly used. Further, when the pressurized liquid chamber 13 as shown in FIG. 1 is manufactured, the silicon single crystal substrate is processed by using etching. As an etching method in this case, it is common to use anisotropic etching. Anisotropic etching utilizes the property that the etching rate differs with respect to the plane orientation of the crystal structure. For example, in anisotropic etching immersed in an alkaline solution such as KOH, the (111) plane has an etching rate of about 1/400 compared to the (100) plane. Therefore, while a structure having an inclination of about 54 ° can be produced in the plane orientation (100), a deep groove can be removed in the plane orientation (110), so that the arrangement density is increased while maintaining rigidity. I know you can. As this configuration example, it is possible to use a single crystal substrate having a (110) plane orientation. However, in this case, SiO ₂ which is a mask material is also etched, so it is preferable to use this point in consideration.

(Diaphragm)
As shown in FIG. 1, upon receiving the force generated by the piezoelectric element 16 as an electromechanical conversion element, the underlying diaphragm 15 is deformed to discharge a liquid droplet such as ink in the pressurized liquid chamber 13. . Therefore, it is preferable that the diaphragm 15 has a predetermined strength. Examples of the material include those made of Si, SiO ₂ , Si ₃ N _{4 and the} like by, for example, a CVD (Chemical Vapor Deposition) method. Further, it is preferable to select a material close to the linear expansion coefficient of the common electrode (lower electrode) 161 and the piezoelectric body 162 as shown in FIG. In particular, as the piezoelectric body 162, PZT is generally used as a material in many cases. Therefore, the material of the diaphragm 15 is in the range of 5 × 10 ⁻⁶ (1 / K) to 10 × 10 ⁻⁶ (1 / K), which is close to the linear expansion coefficient 8 × 10 ⁻⁶ (1 / K) of PZT. A material having a linear expansion coefficient of is preferable. Furthermore, a material having a linear expansion coefficient in the range of 7 × 10 ⁻⁶ (1 / K) to 9 × 10 ⁻⁶ (1 / K) is more preferable. Specific examples of the material include aluminum oxide, zirconium oxide, iridium oxide, ruthenium oxide, tantalum oxide, hafnium oxide, osmium oxide, rhenium oxide, rhodium oxide, palladium oxide, and compounds thereof. These materials can be produced by a spin coater using, for example, a sputtering method or a sol-gel method. The film thickness is preferably in the range of 0.1 [μm] to 10 [μm], and more preferably in the range of 0.5 [μm] to 3 [μm]. If it is smaller than this range, it becomes difficult to process the pressurized liquid chamber 13 as shown in FIG. On the other hand, if it is larger than the above range, the diaphragm 15 is not easily deformed, and ejection of droplets such as ink droplets becomes unstable.

[Lower electrode (common electrode)]
The lower electrode (common electrode) 161 is preferably made of metal or metal and oxide. Here, both materials are devised so as to suppress peeling and the like by putting an adhesion layer between the diaphragm 15 and the metal film constituting the lower electrode 161. Details of the metal electrode film and the oxide electrode film including the adhesion layer are described below.

[Adhesion layer]
The adhesion layer is formed as follows, for example. After Ti is formed by sputtering, the formed titanium film is thermally oxidized using an RTA (Rapid Thermal Annealing) apparatus to form a titanium oxide film. The conditions for thermal oxidation are, for example, a temperature in the range of 650 [° C.] to 800 [° C.], a treatment time in the range of 1 [min] to 30 [min], and an O ₂ atmosphere. To form the titanium oxide film, reactive sputtering may be used, but thermal oxidation of the titanium film at a high temperature is desirable. The production by reactive sputtering requires a special sputtering chamber configuration because the silicon substrate needs to be heated at a high temperature. Furthermore, the crystallinity of the titanium oxide film is better in the oxidation by the RTA apparatus than in the oxidation by a general furnace. This is because, according to oxidation in a normal heating furnace, a titanium film that is easily oxidized forms several crystal structures at a low temperature, and thus it is necessary to break it once. Therefore, oxidation by RTA having a high temperature rising rate is advantageous in order to form better crystals. Moreover, as materials other than Ti, materials such as Ta, Ir, and Ru can be used. The thickness of the adhesion layer is preferably in the range of 10 [nm] to 50 [nm], and more preferably in the range of 15 [nm] to 30 [nm]. If it is less than this range, there is concern about adhesion. Also, if the value exceeds this range, the surface roughness of the lower electrode will increase and the adhesion to the piezoelectric film will decrease, adversely affecting the crystallinity of the piezoelectric film, and sufficient displacement for ink ejection will not be obtained. Trouble occurs.

[Metal electrode film]
Conventionally, platinum having high heat resistance and low reactivity has been used as the metal material of the metal electrode film, but it may not be said that it has sufficient barrier properties against lead. -Platinum group elements, such as rhodium, and these alloy films are also mentioned. Further, when platinum is used, it is preferable that the above-mentioned adhesion layer is laminated first because adhesion to the base (particularly SiO ₂ ) is poor. As a manufacturing method, vacuum film formation such as sputtering or vacuum deposition is generally used. The film thickness is preferably in the range of 80 [nm] to 200 [nm], and more preferably in the range of 100 [nm] to 150 [nm]. When the thickness is smaller than this range, a sufficient current cannot be supplied as the lower electrode 161, and a problem occurs when ejecting a droplet. Further, when the thickness is larger than this range, the cost increases when an expensive material of a platinum group element is used. In the case of using platinum as a material, the surface roughness increases when the film thickness is increased, which affects the surface roughness and crystal orientation of the oxide electrode film and PZT produced thereon. This causes a problem that sufficient displacement for ink ejection cannot be obtained.

[Oxide electrode film]
As a material for the oxide electrode film, it is preferable to use SrRuO ₃ (sometimes simply referred to as SRO). Otherwise, Sr _x (A) _(1-x) Ru _y (B) _(1-y) , A = Ba, Ca, B = Co, Ni, x, y = 0 to 0.5 Also mentioned are other materials. The film forming method is produced by sputtering. The film quality of the SrRuO ₃ thin film varies depending on the sputtering conditions. In particular, in order to place the SrRuO ₃ film in the (111) orientation in accordance with the Pt (111) of the first electrode, in particular, the crystal orientation is important. Is preferably formed by heating the substrate at 500 [° C.] or higher.

  For example, with respect to the SRO film formation conditions described in Japanese Patent No. 3784401, when thermal acidification is performed at a crystallization temperature (650 [° C.]) by RTA treatment after film formation at room temperature, the SRO film is sufficiently crystallized. Although a sufficient value is obtained as the specific resistance as an electrode, (110) is likely to be preferentially oriented as the crystal orientation of the film, and (110) orientation is also easy for PZT formed thereon. Become.

  Regarding SRO crystallinity produced on Pt (111), since the lattice constants of Pt and SRO are close to each other, in the normal θ-2θ measurement, the 2θ positions of SRO (111) and Pt (111) are overlapped, so that discrimination difficult. With respect to Pt, diffraction lines cancel each other at a position where 2θ tilted by Psi = 35 ° is about 32 ° due to the disappearance rule, and no diffraction intensity is observed. Therefore, it is possible to confirm whether the SRO is preferentially oriented to (111) by inclining the Psi direction by about 35 ° and judging from the peak intensity where 2θ is about 32 °.

  FIG. 4 shows an example of a measurement result when 2θ = 32 ° is fixed and Psi is shaken. At Psi = 0 °, almost no diffraction intensity is observed at SRO (110), and diffraction intensity is observed at around Psi = 35 °. It can be confirmed that it is oriented. In addition, regarding the SRO produced by the above-described room temperature film formation + RTA process, the diffraction intensity of SRO (110) is observed when Psi = 0 °.

  In addition, when the amount of displacement after being driven was estimated to be deteriorated compared to the initial displacement when continuously operating as a piezoelectric actuator, the orientation of PZT has a great influence. (110) Insufficient displacement suppression is insufficient. Further, when the surface roughness of the SRO film is observed, the film formation temperature is affected, and the surface roughness is very small from room temperature to 300 [° C.] and becomes 2 [nm] or less. As for the roughness, the surface roughness (average roughness) measured by AFM is used as an index.

  Although the surface roughness is very flat, the crystallinity is not sufficient, and sufficient characteristics cannot be obtained with respect to initial displacement as a piezoelectric actuator of PZT formed after that and displacement deterioration after continuous driving. . The surface roughness is preferably 4 to 15 [nm], and more preferably 6 to 10 [nm]. If this range is exceeded, the dielectric breakdown voltage of the PZT deposited thereafter is very poor and leaks easily. Therefore, in order to obtain the crystallinity and the surface roughness as described above, the film formation temperature is 500 to 700 [° C.], preferably 520 to 600 [° C.]. .

  Regarding the composition ratio of Sr and Ru after film formation, Sr / Ru is preferably 0.82 or more and 1.22 or less. If it is out of this range, the specific resistance increases, and sufficient conductivity as an electrode cannot be obtained.

  Furthermore, the film thickness of the SRO film is preferably 40 to 150 [nm], and more preferably 50 to 80 [m]. If the thickness is smaller than this range, sufficient characteristics may not be obtained for initial displacement and displacement deterioration after continuous driving, and a function as a stop etching layer for suppressing overetching of PZT is also obtained. It becomes difficult. If this range is exceeded, the dielectric breakdown voltage of the PZT deposited thereafter is very poor and leaks easily.

The specific resistance is preferably 5 × 10 ⁻³ [Ω · cm] or less, and more preferably 1 × 10 ⁻³ [Ω · cm] or less. If it is larger than this range, a sufficient current cannot be supplied, and a problem occurs when ink is ejected.

[Piezoelectric body (electromechanical conversion film)]
As a material of the piezoelectric body 162, PZT was mainly used. PZT is a solid solution of lead zirconate (PbZrO ₃ ) and titanic acid (PbTiO ₃ ), and the characteristics differ depending on the ratio. In general, the composition exhibiting excellent piezoelectric characteristics has a ratio of PbZrO ₃ and PbTiO ₃ of 53:47. When expressed by a chemical formula, Pb (Zr0.53, Ti0.47) O ₃ , general PZT (53/47) It is shown. Examples of composite oxides other than PZT include barium titanate. In this case, it is also possible to prepare a barium titanate precursor solution by dissolving barium alkoxide and a titanium alkoxide compound in a common solvent. is there. These materials are described by the general formula ABO ₃ , and A = Pb, Ba, Sr, B = Ti, Zr, Sn, Ni, Zn, Mg, and a composite oxide mainly composed of Nb. Specifically, (Pb1-x, Ba) (Zr, Ti) O ₃ , (Pb1-x, Sr) (Zr, Ti) O ₃ , which partially replaces Pb of the A site with Ba or Sr. This is the case. Such substitution is possible with a divalent element, and the effect thereof has an effect of reducing characteristic deterioration due to evaporation of lead during heat treatment.

  As a method for manufacturing the piezoelectric body 162, it can be manufactured by a spin coater using a sputtering method or a sol-gel method. In that case, since patterning is required, a desired pattern is obtained by photolithography etching (also called lithoetching) or the like. When PZT is produced by the sol-gel method, a PZT precursor solution can be produced by using lead acetate, zirconium alkoxide, and titanium alkoxide compounds as starting materials and dissolving them in methoxyethanol as a common solvent to obtain a uniform solution. Since the metal alkoxide compound is easily hydrolyzed by moisture in the atmosphere, an appropriate amount of a stabilizer such as acetylacetone, acetic acid or diethanolamine may be added to the precursor solution as a stabilizer.

  When a film of the piezoelectric body 162 (PZT film) is obtained on the entire surface of the actuator substrate 14, it is obtained by forming a coating film by a solution coating method such as spin coating and performing heat treatments such as solvent drying, thermal decomposition, and crystallization. It is done. Since the transformation from the coating film to the crystallized film involves volume shrinkage, it is necessary to adjust the precursor concentration so that a film thickness of 100 nm or less can be obtained in one step in order to obtain a crack-free film. Become.

  The film thickness of the piezoelectric body 162 is preferably in the range of 0.5 [μm] to 5 [μm], and more preferably in the range of 1 [μm] to 2 [μm]. If it is smaller than this range, it will not be possible to generate sufficient deformation (displacement), and if it is larger than this range, many layers will be laminated, resulting in an increase in the number of steps and a longer process time.

  The relative permittivity of the piezoelectric body 162 is preferably in the range of 600 to 2000, and more preferably in the range of 1200 to 1600. At this time, when it is smaller than this range, sufficient deformation (displacement) characteristics cannot be obtained, and when it is larger than this range, polarization processing is not performed sufficiently, and sufficient characteristics cannot be obtained for displacement deterioration after continuous driving. A malfunction occurs.

[Upper electrode (individual electrode)]
Unlike the lower electrode material layer, the upper electrode (individual electrode) 163 is not subjected to a high-temperature process such as that for forming the film of the piezoelectric body 162 and the lattice constant matching with the film of the piezoelectric body 162 is not performed later. Since it is not necessary, the material selection width is wider than that of the lower electrode 161. For the upper electrode 163, a platinum film, a metal electrode such as iridium or gold can be used. A laminated film of an oxide electrode layer and a metal electrode can also be used.

  The upper electrode 163 is preferably made of metal or oxide and metal. Details of the oxide electrode film and the metal electrode film are described below.

[Oxide electrode film]
Examples of the material for the oxide electrode film include the same materials as those described for the oxide electrode film used in the lower electrode (common electrode) 161 described above. The oxide electrode film can be produced by a film forming method such as sputtering. The thickness of the oxide electrode film is preferably in the range of 20 [nm] to 80 [nm], and more preferably in the range of 40 [nm] to 60 [nm]. If the thickness is less than this range, sufficient characteristics cannot be obtained for the deterioration characteristics of initial deformation (displacement) and deformation (displacement). On the other hand, if it exceeds this range, the withstand voltage of the PZT film formed thereafter deteriorates and leaks easily.

[Metal electrode film]
Examples of the material for the metal electrode film include the same materials as those described for the metal electrode film used in the lower electrode (common electrode) 161 described above. The thickness of the metal electrode film is preferably in the range of 30 [nm] to 200 [nm], and more preferably in the range of 50 [nm] to 120 [nm]. When the thickness is smaller than this range, a sufficient current cannot be supplied as the upper electrode (individual electrode) 163, and a problem occurs when ejecting a droplet. On the other hand, when the thickness is larger than the above range, the cost increases when an expensive material of a platinum group element is used. In addition, when platinum is used as the material, the surface roughness increases when the film thickness is increased, and process defects such as film peeling are likely to occur when wiring is formed through an insulating protective film. .

[First insulating protective film]
The material of the first insulating protective film 17 needs to be a dense inorganic material because it is necessary to select a material that prevents moisture in the atmosphere from being transmitted through while preventing damage to the piezoelectric element due to the film formation / etching process. There is. Further, when an organic material is used for the first insulating protective film 17, it is not suitable because it is necessary to increase the film thickness in order to obtain sufficient protection performance. When the first insulating protective film 17 is a thick film, the vibration of the diaphragm 15 is remarkably hindered, resulting in a droplet discharge head having a low discharge performance. In order to obtain high protection performance with a thin film, it is preferable to use an oxide, nitride, or carbide film. However, the electrode material, the piezoelectric material, and the diaphragm material serving as the base of the first insulating protective film 17 have adhesiveness. It is necessary to select a high material. In addition, it is necessary to select a film forming method that does not damage the piezoelectric element 16 as a method for forming the first insulating protective film 17. That is, a plasma CVD method in which a reactive gas is turned into plasma and deposited on a substrate, or a sputtering method in which a film is formed by causing a plasma to collide with a target material and flying away is not preferable. Examples of a preferable film formation method for the first insulating protective film 17 include an evaporation method and an ALD (Atomic Layer Deposition) method, but an ALD method with a wide range of materials that can be used is preferable. Preferred _{materials, Al 2 O 3, ZrO 2} , Y2O 3, Ta 2 O 3, an oxide film used in the ceramic material, such as TiO ₂ can be cited as examples. In particular, by using the ALD method, a thin film having a very high film density can be produced and damage in the process can be suppressed.

  The film thickness of the first insulating protective film 17 needs to be thin enough to ensure the protection performance of the piezoelectric element 16, and at the same time, it is made as thin as possible so as not to inhibit the deformation (displacement) of the diaphragm 15. There is a need. The thickness of the first insulating protective film 17 is preferably in the range of 20 [nm] to 100 [nm]. When the thickness is greater than 100 [nm], the deformation (displacement) amount of the vibration plate 15 is reduced, so that a droplet discharge head with low discharge efficiency is obtained. On the other hand, when the thickness is smaller than 20 [nm], the function of the piezoelectric element 16 as a protective layer is insufficient, so that the performance of the piezoelectric element 16 is deteriorated as described above.

[Second insulating protective film]
As the second insulating protective film 18, any oxide, nitride, carbide, or composite compound thereof can be used, and SiO ₂ generally used in semiconductor devices can also be used. Arbitrary methods can be used for forming the second insulating protective film 18, and examples thereof include a CVD method, a sputtering method, and an ALD method. It is preferable to use a CVD method capable of forming an isotropic film in consideration of the step coverage of the pattern forming portion such as the electrode forming portion. The film thickness of the second insulating protective film 18 needs to be a film thickness that does not cause dielectric breakdown by a voltage applied between the common electrode (lower electrode) 161 and the wiring 32 of the individual electrode. That is, it is necessary to set the electric field strength applied to the second insulating protective film 18 within a range that does not cause dielectric breakdown. Furthermore, in consideration of the surface property of the base of the second insulating protective film 18, pinholes, etc., the thickness of the second insulating protective film 18 needs to be 200 [nm] or more, more preferably 500 [nm] or more. It is.

[Wiring, pad electrode]
The material of the wirings 31 and 22 and the pad electrode is preferably a metal electrode material made of Ag alloy, Cu, Al, Au, Pt, or Ir. As a method for manufacturing these electrodes, a sputtering method or a spin coating method is used, and then a desired pattern is obtained by photolithography etching or the like. The film thickness is preferably in the range of 0.1 [μm] to 20 [μm], and more preferably in the range of 0.2 [μm] to 10 [μm]. If it is smaller than this range, the resistance becomes large, and a sufficient current cannot flow through the electrodes, making the head ejection unstable. On the other hand, if it is larger than this range, the process time becomes longer. Further, the contact resistance in the contact hole portion (for example, 10 [μm] × 10 [μm]) connected to the lower electrode 161 and the upper electrode 163 is 10 [Ω] or less with respect to the lower electrode 161 that is a common electrode. The upper electrode 163 that is an individual electrode is preferably 1 [Ω] or less. More preferably, it is 5 [Ω] or less for the lower electrode 161 and 0.5 [Ω] or less for the upper electrode 163. If it exceeds this range, it will not be possible to supply a sufficient current, and problems will occur when discharging droplets.

[Third insulating protective film]
The function as the third insulating protective film 19 is a passivation layer having a function as a protective layer of the common electrode wiring 31 and the individual electrode wiring 32. As shown in FIG. 2, the upper electrode 163 and the lower electrode 161 are covered except for the lead portion of the upper electrode 163 and the lead portion (contact hole 18a) of the lower electrode 161. Thereby, an inexpensive Al or an alloy material containing Al as a main component can be used as the electrode material. As a result, a low-cost and highly reliable droplet discharge head (inkjet head) can be obtained. As the material of the third insulating protective film 19, any inorganic material or organic material can be used, but it is necessary to use a material with low moisture permeability. Examples of the inorganic material include oxides, nitrides, and carbides, and examples of the organic material include polyimide, acrylic resin, and urethane resin. However, an organic material is not suitable for patterning because it needs to be a thick film. Therefore, it is preferable to use an inorganic material that can exhibit a wiring protection function with a thin film. In particular, it is preferable to use Si ₃ N ₄ on the Al wiring because it is a proven technology for semiconductor devices. The film thickness is preferably 200 [nm] or more, and more preferably 500 [nm] or more. When the film thickness is small, a sufficient passivation function cannot be exhibited, so that disconnection due to corrosion of the wiring material occurs, and the reliability of the ink jet is lowered.

Further, a structure having openings on the piezoelectric element 16 and the surrounding diaphragm 15 is preferable. This is the same reason that the region corresponding to the pressurized liquid chamber 13 of the first insulating protective film 17 is thinned. As a result, a highly efficient and highly reliable droplet discharge head (inkjet head) can be obtained. Since the piezoelectric element 16 is protected by the first and second insulating protective films 17 and 18, a photolithography method and dry etching can be used to form the opening of the third insulating protective film 19. Note that the area of the pad electrode is preferably 50 × 50 [μm ² ] or more, and more preferably 100 × 300 [μm ² ] or more.

(Production of Subframe Substrate, First Embodiment)
[Production process overview]
First, an outline of manufacturing the subframe substrate 30 will be described.

  FIG. 5 is a top view of the subframe substrate 30. The subframe substrate 30 is a substrate bonded to the surface of the actuator substrate 14 on which the piezoelectric element 16 is formed.

<Groove formation process>
The subframe substrate 30 shown in FIG. 5 is a silicon substrate, and around a portion where the through hole 37 is formed (that is, a portion that becomes the common droplet flow path 36) (a predetermined range on the inner side along the outer diameter shape). The through hole forming groove 38 is formed by penetrating the film by dry etching.
A cutout portion 39 is formed in a portion surrounded by the through hole forming groove 38. At this time, the groove width of the through-hole forming groove 38 is preferably a single groove width. Also, counterbore 34 is formed.

<Removal process>
Then, as shown in FIG. 6, the subframe substrate 30 in which the through holes 37 are formed is created by removing the cutout portions 39.

  Although details will be described later, in the method for manufacturing the subframe substrate 30 according to the present embodiment, when the through-hole forming groove 38 is penetrated through the subframe substrate 30 by dry etching, the electrode of the etcher (etching apparatus) is damaged. In order not to give, the support substrate 50 as a protective substrate is affixed on the back surface side of the sub-frame substrate 30 via the adhesive sheet 42 (FIG. 10 etc.).

  A narrow groove is formed as a mask around the through hole 37, and the groove is penetrated to form the through hole forming groove 38 shown in FIGS. When the support substrate 50 and the adhesive sheet 42 are peeled off after the through-hole forming groove 38 is formed, the cut-out portion 39 is removed by the adhesive force of the adhesive sheet 42. Thereby, the through-hole 37 is formed.

  That is, in the manufacturing method of the subframe substrate 30 according to the present embodiment, the entire portion of the opening of the pattern to be penetrated having various shapes and areas is not etched, but the portion that becomes the through hole 37 is formed by a single width groove. Since the periphery is etched, there is no difference in etching rate due to the microloading effect of etching, and there is no change in shape in the depth direction due to the difference in opening area. The through-hole 37 can be formed without variation. Therefore, it is possible to improve the yield and cope with miniaturization.

  In addition, the amount of reaction products during etching is reduced, so that deposits on the etching apparatus can be reduced. For example, the maintenance cycle of the etching apparatus can be extended, and the maintenance cost of the apparatus can be suppressed. Can do.

[Production process details]
Hereinafter, details of the manufacturing process of the subframe substrate 30 will be described with reference to FIGS. In addition, the 1st-6th process demonstrated below is a groove | channel formation process, and a 7th process is a removal process.

  7 is a top view of the subframe substrate 30 in which the counterbore 34 and the through hole forming groove 38 are formed. FIGS. 8 to 15 are cross-sectional views of the subframe substrate 30 in the short side length direction (AA ′ cross section). FIG. 6 is an explanatory diagram of a manufacturing process of the subframe substrate 30. In the following description, the upper surface of the subframe substrate 30 in the drawing is referred to as the front surface (the surface on the actuator substrate 14 side), and the lower surface in the drawing is referred to as the back surface.

<First step>
First, as shown in FIG. 8, when a through-hole forming groove 38 and counterbore 34 are formed on a silicon single crystal substrate 40 (for example, 400 μm thick) having a double-sided mirror surface with a plane orientation (110) as a subframe substrate 30 later. The SiO ₂ film 41 serving as an etching mask is formed on both surfaces of the silicon single crystal substrate 40 by LP-CVD (for example, having a thickness of 500 nm).

<Second step>
Next, as shown in FIG. 9, on the back side of the subframe substrate 30, the SiO ₂ film 41 at a location that will later be located in the through-hole forming groove 38 is removed by a litho-etching method (lithography / etching method). 41a).

Further, on the surface side of the sub-frame substrate 30, the SiO ₂ film 41 that will be the counterbore 34 later is removed by a litho-etching method (reference numeral 41 b in the figure).

<Third step>
Next, as shown in FIG. 10, when the through hole forming groove 38 is penetrated by dry etching, the support substrate 50 is attached to the subframe substrate 30 using an adhesive sheet 42 in order to protect the electrode of the etcher from plasma. Paste. The adhesive sheet 42 can be peeled later, and for example, a heat peeling type bonding tape can be used.

  Further, a resist 43 is applied to the surface of the subframe substrate 30, and a pattern 43a of the through hole forming groove 38 is formed by exposure and development using a general photomask.

<4th process>
Next, as shown in FIG. 11, the SiO ₂ film 41 at a location that will later become the through hole forming groove 38 is removed by a general oxide film dry etching through the resist pattern to form a pattern 41 c. .

<Fifth step>
Next, as shown in FIG. 12, for example, an ICP (Inductively Coupled Plasma) etching apparatus using a high-density plasma source is used to penetrate the silicon single crystal substrate 40, and a through-hole forming groove 38 is formed with a pattern 41 a of a resist 43. Form. Thereby, a cutout portion 39 surrounded by the through hole forming groove 38 is also formed.

<Sixth step>
Next, as shown in FIG. 13, the resist 43 is removed by ashing. Then, again, the counterbore 34 is etched to a depth of 10 to 30 μm, for example, using the SiO ₂ film 41 as a mask by ICP etching.

<Seventh step>
Next, as shown in FIG. 14, in order to peel the support substrate 50 from the sub-frame substrate 30, the support substrate 50 is peeled while being heated to a temperature at which heat separation is performed and the adhesive sheet 42 remains on the sub-frame substrate 30.

  Next, the adhesive sheet 42 is peeled from the subframe substrate 30. At this time, the cut-out portion 39 is removed while attached to the adhesive sheet 42.

  Thereby, the through-hole 37 is formed by the part where the through-hole forming groove 38 is formed and the part where the cut-out portion 39 is formed.

<Eighth process>
Next, as shown in FIG. 15, the SiO ₂ film 41 is removed by a wet etch layer (for example, hydrofluoric acid). Thereafter, in order to provide the subframe substrate 30 with ink resistance, a liquid contact film 44 is formed using an ALD (atomic layer deposition) method or the like according to the ink to be used. The subframe substrate 30 is completed through the above steps.

  The subframe substrate 30 (third substrate) is bonded to the actuator substrate 14 (second substrate) to which the nozzle substrate 12 (first substrate) is bonded, whereby the droplet discharge head 1 is created. .

  As described above, according to the substrate manufacturing method according to the present embodiment, the size and shape can be controlled easily and with high accuracy.

  More specifically, in the substrate manufacturing method according to the present embodiment, when forming a through hole in a silicon substrate, the through hole is formed using only dry etching. Therefore, simplification of the process, reduction of process cost, equipment cost, and improvement of yield can be achieved. In addition, since the process and design restrictions are smaller than in the prior art, design and process construction with a high degree of freedom can be performed.

  In addition, during penetration of the through hole, etching should be performed with the support substrate attached to the back surface of the substrate on which the through hole is formed so as not to expose the electrode of the dry etching apparatus to plasma through a peelable adhesive member. ing.

  In addition, when the through hole is penetrated, the etching area is reduced because the groove is not etched over the entire surface of the opening pattern but along the periphery of the opening (the outer diameter shape of the through hole forming region). . For this reason, the reaction product at the time of etching decreases, and deposit adhesion in the etching apparatus chamber can be suppressed. Therefore, the chamber cleaning cycle can be lengthened, and the maintenance cost can be reduced.

  In addition, by making the groove width a single groove width, there is no difference in etching rate due to the microloading effect of etching, and there is no change in shape in the depth direction due to the difference in opening area. However, it is possible to improve the processing accuracy, and to form the through hole with high dimensional accuracy and without variation in shape. Thus, by enabling the size and shape control with high accuracy, it is possible to realize production of a product that is advantageous for high accuracy and miniaturization. In addition, the yield can be improved and the cost can be reduced.

  Further, by using the droplet discharge head 1 provided with the substrate produced by the substrate manufacturing method according to the present embodiment as the subframe substrate 30, a highly accurate, reliable and stable droplet discharge head can be obtained. Well realized.

(Second Embodiment)
Hereinafter, another embodiment of a method for manufacturing a substrate according to the present invention will be described. In addition, the description about the same point as the said embodiment is abbreviate | omitted suitably.

  FIG. 16 is another example of a top view of the subframe substrate 30 in which the counterbore 34 and the through hole forming groove 38 are formed.

  In the first embodiment, the through-hole forming groove 38 is formed along the outer diameter shape of the through-hole 37, and the cutout portion 39 has a rectangular parallelepiped shape with a long side length direction of the subframe substrate 30 being long (see FIG. 7).

  For this reason, in the removing process, when the adhesive sheet 42 is peeled off from the end portion of the subframe substrate 30 and peeled, for example, if the curvature of the adhesive sheet 42 is small, the cut-out portion 39 can follow the curvature of the adhesive sheet 42. Instead, there may be a case in which the peeled portion 39 is peeled off or broken from the adhesive sheet 42 during the peeling. In this case, the inner wall of the through-hole 37 may be damaged or foreign matter may adhere.

  Therefore, in the substrate manufacturing method according to the second embodiment, the through-hole 39 surrounded by the through-hole forming groove 38 is also formed in the through-hole 39 so as to follow the curvature when the adhesive sheet 42 is peeled off from the subframe substrate 30. The formation groove 38 is formed. Further, the through hole forming groove 38 is preferably formed in the short side direction of the cut-out portion 39 as shown in FIG.

  Thus, by forming the through-hole forming groove 38, the cut-out portion 39 is reliably attached to the adhesive sheet 42 when the adhesive sheet 42 is peeled off more preferably than the example of the first embodiment. It can be peeled off as it is.

  Therefore, it is not peeled off or broken from the adhesive sheet 42 in the middle of peeling of the cut-out portion 39, and the inner wall of the through hole 37 is not damaged or foreign matter is not attached. Therefore, the subframe substrate 30 can be manufactured with high quality and high yield.

(ink cartridge)
Next, an ink cartridge provided with the droplet discharge head 1 according to the present embodiment will be described.

  FIG. 17 is a perspective view illustrating a configuration example of an ink cartridge including the droplet discharge head 1. The ink cartridge 90 is obtained by integrating the above-described droplet discharge head 1 (inkjet head) and an ink tank 91 that supplies ink to the droplet discharge head 1.

  When the droplet discharge head 1 and the ink tank 91 are integrated, the performance improvement of the droplet discharge head 1 immediately leads to the improvement of the overall performance of the ink cartridge 90. Therefore, by improving the performance of the droplet discharge head 1, the performance of the head-integrated ink cartridge 90 can be improved.

(Image forming device)
Next, an ink jet recording apparatus which is an image forming apparatus provided with the droplet discharge head 1 according to the present embodiment will be described.

  FIG. 18 is a perspective view showing a configuration example of an ink jet recording apparatus equipped with a droplet discharge head, and FIG. 19 is a side view showing a configuration example of a mechanism section of the recording apparatus.

  The ink jet recording apparatus 100 houses a printing mechanism 103 and the like inside the apparatus main body, and may be a paper feed cassette (or a paper feed tray) on which a large number of recording sheets 130 can be stacked from the front side in the lower part of the apparatus main body. ) 104 is removably mounted. Further, it has a manual feed tray 105 that is opened to manually feed the recording paper 130. The recording paper 130 fed from the paper feed cassette 104 or the manual feed tray 105 is taken in, a required image is recorded by the printing mechanism unit 103, and then discharged to the paper discharge tray 106 mounted on the rear side.

  The printing mechanism 103 includes a carriage 101 that can move in the main scanning direction, a droplet discharge head mounted on the carriage 101, an ink cartridge 102 that supplies ink to the droplet discharge head, and the like. Further, the printing mechanism 103 holds the carriage 101 slidably in the main scanning direction with a main guide rod 107 and a sub guide rod 108 which are guide members horizontally mounted on left and right side plates (not shown). The carriage 101 has a droplet discharge head for discharging ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk) through a plurality of ink discharge ports (nozzle holes) in the main scanning direction. And are mounted with the ink droplet ejection direction facing downward. In addition, each ink cartridge 102 for supplying ink of each color to the droplet discharge head is replaceably mounted on the carriage 101.

  The ink cartridge 102 is provided with an air opening communicating with the atmosphere above, and a supply opening for supplying ink to the droplet discharge head below. The ink cartridge 102 has a porous body filled with ink, and the ink supplied to the droplet discharge head is maintained at a slight negative pressure by the capillary force of the porous body. Further, although the droplet discharge heads of the respective colors are used as the droplet discharge heads, one droplet discharge head having nozzle holes for discharging the ink droplets of the respective colors may be used.

  Here, the carriage 101 is slidably fitted to the main guide rod 107 on the rear side (downstream side in the paper conveyance direction), and is slidably mounted on the sub guide rod 108 on the front side (upstream side in the paper conveyance direction). ing. In order to move and scan the carriage 101 in the main scanning direction, a timing belt 112 is stretched between a driving pulley 110 and a driven pulley 111 that are rotationally driven by a main scanning motor 109a. It is fixed to. As a result, the carriage 101 is driven to reciprocate by forward and reverse rotation of the main scanning motor a109.

  On the other hand, in order to convey the recording paper 130 set in the paper feeding cassette 104 to the lower side of the droplet discharge head, a paper feeding roller 113 and a friction pad 114 for separating and feeding the recording paper 130 from the paper feeding cassette 104, and recording And a guide member 115 for guiding the paper 130. Further, a conveyance roller 116 that reverses and conveys the fed recording paper 130, a conveyance roller 117 that is pressed against the peripheral surface of the conveyance roller 116, and a leading roller that defines the feeding angle of the recording paper 130 from the conveyance roller 116. 118. The conveyance roller 116 is rotationally driven via a gear train by the sub-scanning motor 109b.

  In addition, a printing receiving member 119 that is a paper guide member is provided to guide the recording paper 130 fed from the transport roller 116 corresponding to the range of movement of the carriage 101 in the main scanning direction on the lower side of the droplet discharge head. Yes. On the downstream side of the printing receiving member 119 in the paper conveyance direction, a conveyance roller 120 and a spur 121 that are rotationally driven to send the recording paper 130 in the paper discharge direction are provided. Further, a discharge roller 123 and a spur 124 for feeding the recording paper 130 to the discharge tray 106, and guide members 125 and 126 for forming a discharge path are provided.

  At the time of recording with the ink jet recording apparatus 100, the droplet discharge head is driven in accordance with the image signal while moving the carriage 101, whereby ink is discharged onto the stopped recording paper 130 to record one line. Thereafter, the recording paper 130 is conveyed by a predetermined amount, and then the next line is recorded. Upon receiving a recording end signal or a signal that the trailing edge of the recording paper 130 reaches the recording area, the recording operation is terminated and the recording paper 130 is discharged.

  Further, a recovery device 127 for recovering the ejection failure of the droplet ejection head is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 101. The recovery device 127 includes a cap unit, a suction unit, and a cleaning unit. During printing standby, the carriage 101 is moved to the recovery device 127 side, and the droplet ejection head is capped by the capping unit to keep the ejection port portion in a wet state, thereby preventing ejection failure due to ink drying. Further, by ejecting ink that is not related to recording during recording or the like, the ink viscosity of all the ejection ports is made constant and stable ejection performance is maintained.

  When a discharge failure occurs, the discharge port (nozzle hole) of the droplet discharge head 1 is sealed with a capping unit, and bubbles and the like are sucked out from the discharge port through the tube with the suction unit. In this way, ink or dust adhering to the ejection port surface is removed by the cleaning means, and the ejection failure is recovered. The sucked ink is discharged to a waste ink reservoir installed at the lower part of the main body, and is absorbed and held by an ink absorber inside the waste ink reservoir. As described above, since the inkjet recording apparatus 100 of the present embodiment includes the recovery device 127, the ejection failure of the droplet ejection head is recovered, stable ink droplet ejection characteristics are obtained, and the image quality is improved. be able to.

  As described above, since the ink jet recording apparatus (image forming apparatus) 100 according to the present embodiment includes the liquid droplet ejection head 1 according to the present embodiment as a recording head, the ink jet recording apparatus 100 including the high quality liquid droplet ejection head 1 and can do.

  In addition, although an inkjet printer has been described as an example of the image forming apparatus, the present invention can also be applied to an inkjet copy, an inkjet fax, or a composite recording apparatus thereof. Further, the image forming apparatus includes both a serial type image forming apparatus and a line type image forming apparatus, unless otherwise limited.

  Further, in an ink jet recording apparatus, an image is formed by adhering ink droplets to a sheet by a droplet discharge head while conveying a medium. The medium here is also referred to as “paper”, but the material is not limited, and a recording medium, a recording medium, a transfer material, a recording paper, and the like are also used synonymously. The image forming apparatus means an apparatus for forming an image by ejecting liquid droplets on a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, or ceramic.

  The image formation is not only giving an image having a meaning such as a character or a figure to the medium but also giving an image having no meaning such as a pattern to the medium (simply ejecting a droplet). Also means. The ink is not limited to so-called ink, and is not particularly limited as long as it becomes a droplet when ejected. For example, the ink is a generic term for liquids including DNA samples, resists, pattern materials, and the like. Used as For example, in addition to an inkjet recording apparatus, the present invention can be applied to industrial manufacturing apparatuses such as a color filter manufacturing apparatus, a metal wiring manufacturing apparatus, a textile printing apparatus, and a DNA chip manufacturing apparatus using an inkjet technique.

  The above-described embodiment is a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Droplet discharge head 10 Droplet discharge part 11 Nozzle hole 12 Nozzle board 13 Pressurized liquid chamber 14 Actuator board 15 Diaphragm 16 Piezoelectric element 161 Lower electrode 162 Piezoelectric body 163 Upper electrode 17 1st insulating protective film 17a Contact hole 18 Second insulating protective film 18a Contact hole 19 Third insulating protective film 20 Driving IC
21 Fluid resistance portion 22 Common liquid chamber 30 Sub-frame substrate 31, 32 Wiring 33 Pad electrode 34 Counterbore 35 Droplet supply port 36 Common droplet flow path 37 Through hole 38 Through hole forming groove 39 Cutout portion 40 Silicon single crystal substrate 41 SiO ₂ film 42 adhesive sheet 43 resist 44 wetted film 50 support substrate 90 ink cartridge 100 inkjet recording apparatus

JP 2004-167951 A JP2013-43437A

Claims (5)

A method for producing a substrate used in a droplet discharge head,
A groove forming step of forming a through hole forming groove by allowing a portion along the outer diameter shape of the portion forming the through hole in the substrate to pass through in a groove shape by dry etching;
A removing step of removing a portion surrounded by the through hole forming groove;
Have a,
In the groove forming step, a groove is penetrated in a portion surrounded by the through hole forming groove . In the groove forming step, a sheet-like adhesive member is bonded to the surface opposite to the surface on which the through-hole forming groove starts to be formed,
2. The method for manufacturing a substrate according to claim 1, wherein, in the removing step, a portion surrounded by the through hole forming groove is removed by peeling the adhesive member from the substrate. In the groove forming step, a protective substrate is bonded to the substrate with the adhesive member interposed therebetween,
3. The method for manufacturing a substrate according to claim 2, wherein, in the removing step, the adhesive member is peeled from the substrate after the protective substrate is peeled from the adhesive member.   4. The method for manufacturing a substrate according to claim 1, wherein, in the groove forming step, a groove width of the through hole forming groove is formed as a single groove width. In the groove forming step, a method for manufacturing a substrate according to any one of claims 1 to 4, characterized in that passing the groove in the short side direction of the portion surrounded by the through hole forming groove.