JP2007276308A - Method for manufacturing electrostatic actuator, method for manufacturing droplet discharge head, and method for manufacturing droplet discharge apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrostatic actuator by which, when selectively performing a predetermined treatment to a silicon substrate using a mask substrate, the adhesion of the silicon substrate with the mask substrate can be enhanced and the treatment can be performed only to a target part, and it is possible to produce a highly reliable electrostatic actuator. <P>SOLUTION: The method for manufacturing an electrostatic actuator has a treatment step for selectively performing a predetermined treatment to a part of a silicon substrate 41. The treatment step comprises an adhesion step for attaching a mask substrate 50 to a silicon substrate 41 by vacuum suction, wherein the mask substrate 50 comprises through-holes for treatment (an electrode taking out hole 51 and a sealing hole 52) in the part corresponding to the treatment part for performing a predetermined treatment and suction cup recesses 53 and 54 for forming a space for maintaining vacuum between the mask substrate and the silicon substrate 41, and a step for performing a predetermined treatment to the silicon substrate 41 through the through-holes for treatment of the mask substrate 50. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an electrostatic actuator, a method for manufacturing a droplet discharge head, and a method for manufacturing a droplet discharge device, which are used as a drive mechanism for an inkjet head or the like.

  As a droplet discharge method for a printer or the like, a discharge chamber (also referred to as a pressure chamber) that stores discharge liquid is provided in a part of the flow path, and at least one wall of the discharge chamber (here, a bottom wall, hereinafter, There is a method in which a droplet is discharged from a communicating nozzle by increasing the pressure in the discharge chamber by bending and displacing the wall (hereinafter referred to as a diaphragm). In this case, as a force for displacing the diaphragm serving as the movable electrode, the diaphragm and the counter electrode (fixed electrode) are opposed to each other through a gap to constitute an actuator, and static electricity generated by applying a voltage between them. One that uses force is widely known.

  As a method of manufacturing the electrostatic actuator as described above or a droplet discharge head using the electrostatic actuator, after bonding a silicon substrate before forming a flow path to an electrode glass substrate on which a plurality of electrodes to be fixed electrodes are formed, A method of thinning the silicon substrate and forming a flow path such as a discharge chamber has been proposed (see, for example, Patent Document 1 or Patent Document 2).

JP 2004-82572 A JP 2004-306444 A

  In the above-described conventional method, an electrode extraction opening for connecting a plurality of electrodes to an external device and a sealing opening for sealing a gap between the diaphragm and the counter electrode (fixed electrode) are also provided on the silicon substrate. Formed. When forming these openings, first, a silicon mask having through holes formed only in the portions corresponding to the opening forming portions is prepared, and the silicon mask is placed on the silicon substrate so that portions other than the opening forming portions are formed. Protection is performed and etching is performed through the through-hole in this state, so that openings are selectively formed only in the openings.

  As described above, when the silicon mask is used to selectively process the silicon substrate, it is important to improve the adhesion between the silicon mask and the silicon substrate. This is because if the adhesiveness is not sufficient, the gas used in the process (here, the etching gas) goes around the gap between the silicon mask and the silicon substrate and etches the portion that should be protected originally. As described above, it is important to improve the adhesion between the silicon mask and the silicon substrate, but the above-mentioned prior art document has not mentioned anything about this point.

  The present invention has been made in view of the above problems, and when performing a predetermined process selectively on a silicon substrate using a mask substrate, the adhesion between the silicon substrate and the mask substrate is improved and only the target portion is processed. An object of the present invention is to provide an electrostatic actuator manufacturing method, a droplet discharge head manufacturing method, and a droplet discharge device manufacturing method that can be performed and that can manufacture a highly reliable electrostatic actuator.

An electrostatic actuator manufacturing method according to the present invention includes an electrode glass substrate on which individual electrodes are formed, and a silicon substrate on which a vibration plate that operates by electrostatic force generated between the individual electrodes is formed. An electrostatic actuator having a joining step for joining the diaphragm so as to face each other through a gap, and a processing step for selectively performing a predetermined process on a part of the silicon substrate of the joining substrate formed in the joining step In the manufacturing method, the processing step includes a processing through hole in a portion corresponding to a processing portion for performing a predetermined processing, and a recess for forming a vacuum holding space between the processing substrate and the silicon substrate. The mask substrate is attached to and adhered to the silicon substrate by vacuum suction, and a predetermined process is performed on the silicon substrate through the processing through hole of the mask substrate.
As a result, it becomes possible to attach the mask substrate and the bonding substrate in close contact with each other, and the gas used for processing flows between the mask substrate and the bonding substrate, so that processing is performed on portions that should not be processed originally. This makes it possible to perform target processing only on the target portion. Therefore, a highly reliable electrostatic actuator can be manufactured efficiently.

Further, in the method for manufacturing an electrostatic actuator according to the present invention, the mask substrate is positioned and brought into contact with the bonding substrate, and then placed in the vacuum box, the vacuum box is gradually evacuated and then suddenly released to the atmosphere. Thus, the mask substrate and the bonding substrate are vacuum-adsorbed.
Thereby, the alignment and attachment of the mask substrate to the bonding substrate can be easily performed.

Further, in the method for manufacturing an electrostatic actuator according to the present invention, the predetermined processing is performed by using an electrode for taking out a sealing opening and an individual electrode for forming a sealing portion for sealing a gap in a silicon substrate. This is a process of penetrating the extraction opening by dry etching.
As a result, when forming the sealing opening and the electrode extraction port, it is possible to prevent the etching gas from flowing in, and it is possible to perform etching only on the target portion, and a highly reliable electrostatic actuator can be efficiently used. Can be manufactured well.

In the method for manufacturing the electrostatic actuator according to the present invention, the predetermined process is a process of depositing a sealing material through the sealing opening of the silicon substrate and forming a sealing portion for sealing the gap. Is.
Thereby, when depositing the sealing material, it is possible to prevent the film-forming gas from flowing around, and the sealing material can be efficiently deposited only on the target portion. In addition, since it is possible to prevent adhesion to a portion where the sealing material should not be originally attached, it is possible to prevent connection failure and prolong the life by reliable sealing.

  Moreover, it is preferable that the sealing material is deposited by a CVD method or a sputtering method. According to these, it is possible to easily deposit a highly airtight sealing material on a target portion.

Further, in the manufacturing method of the electrostatic actuator according to the present invention, the mask substrate is provided with a recess so as to communicate with the through hole penetrating the electrode glass substrate and the silicon substrate. The tape substrate is attached to the silicon substrate with the through hole closed, and the mask substrate is attached to the silicon substrate by vacuum suction. When the mask substrate and the bonding substrate are detached, the tape is peeled off. It is.
Thereby, the mask substrate and the bonding substrate can be easily detached.

A method for manufacturing a droplet discharge head according to the present invention is a method for manufacturing a droplet discharge head by applying any one of the above-described methods for manufacturing an electrostatic actuator.
Thereby, a highly reliable droplet discharge head can be manufactured.

In addition, a method for manufacturing a droplet discharge head according to the present invention is a method for manufacturing a droplet discharge head by applying the above-described electrostatic actuator manufacturing method, and a through hole is provided in the droplet discharge head from the outside. It is a liquid intake hole for taking in the discharge liquid.
In this way, instead of forming a new through hole as a through hole for easily detaching the mask substrate and the bonding substrate, a liquid intake hole necessary as a droplet discharge head can be used.

Further, a droplet discharge device according to the present invention is a device for manufacturing a droplet discharge device by applying the above-described method for manufacturing a droplet discharge head.
Thereby, a highly reliable droplet discharge device can be obtained.

Embodiment 1
FIG. 1 is an exploded view of a droplet discharge head according to Embodiment 1 of the present invention. FIG. 1 shows a face discharge type droplet discharge head. As shown in FIG. 1, this droplet discharge head is formed by laminating three substrates: a cavity plate 1, an electrode glass substrate 2, and a nozzle plate 3.
The cavity plate 1 has a thickness of about 50 μm, for example, and is composed of a silicon single crystal substrate (hereinafter simply referred to as a silicon substrate) having a 110-plane orientation. The cavity plate 1 is formed with a plurality of discharge chambers 5 that hold droplets before being discharged, and a flow path such as a reservoir 7 that is common to the discharge chambers 5 that store liquid supplied to the discharge chambers 5. Has been. The bottom wall constituting the bottom surface of the discharge chamber 5 acts as the diaphragm 4. Further, as will be described later, a sealing opening 27 for depositing a sealing material 26 to form a sealing portion is formed through the cavity plate 1.

Further, a TEOS film (Tetraethyl orthosilicate Tetraethoxysilane: SiO ₂ film made of tetraethoxysilane) 14 serving as an insulating film is formed on the lower surface of the cavity plate 1 (the surface facing the electrode glass substrate 2) by plasma CVD ( A film of about 0.1 μm is formed by using a chemical vapor deposition method or the like. This is to prevent breakdown of the insulating film and short circuit when the droplet discharge head is driven. Further, an SiO ₂ film (including a TEOS film) that becomes the liquid protective film 15 is formed on the upper surface of the cavity plate 1 (the surface facing the nozzle plate 3) by plasma CVD or sputtering. This is to prevent the channel from being corroded by a liquid such as ink. Further, it is possible to expect an effect that the stress of the liquid protective film 15 and the stress of the TEOS film 14 formed on the lower surface of the cavity plate 1 are offset, and the warp of the diaphragm 4 can be reduced.
The cavity plate 1 is provided with a common electrode 19 as an energization part of the cavity plate 1.

  The electrode glass substrate 2 has a thickness of about 1 mm, for example, and is a substrate bonded to the lower surface of the cavity plate 1 when viewed in FIG. In the present embodiment, borosilicate heat-resistant hard glass is used as the glass to be the electrode glass substrate 2. The electrode glass substrate 2 is provided with a recess 9 having a depth of about 0.2 μm by etching in accordance with each discharge chamber 5 formed in the cavity plate 1. A plurality of electrodes including individual electrodes 8, lead portions 10, and electrode terminals 11 are provided inside the recess 9. The lead portion 10 is a portion that connects the individual electrode 8 and the electrode terminal 11, and the electrode terminal 11 is a portion that is used when the individual electrode 8 is connected to an external device (for example, a power source). In addition, when it is not necessary to distinguish in particular, the individual electrode 8, the lead portion 10, and the electrode terminal 11 are collectively described as an individual electrode (or electrode) 8.

In the present embodiment, transparent ITO (Indium Tin Oxide) doped with tin oxide as an impurity is used as the material of the individual electrode 8, and the recess 9 has a thickness of 0.1 μm, for example, by sputtering. It shall be formed inside. At that time, as will be described later, an ITO pattern 24 which becomes a contact for equalizing the individual electrode 8 and the silicon substrate bonded to the electrode glass substrate 2 (hereinafter referred to as equipotential contact) is also formed simultaneously with the individual electrode 8. Keep a film.
The material of the individual electrode 8 is not limited to ITO, and a metal such as chromium may be used as the material. In the present embodiment, ITO is used for reasons such as easy inspection in the gap between the electrodes.
The electrode glass substrate 2 is also formed with a liquid intake hole 13 serving as a flow path for taking the discharged liquid from an external tank (not shown) into the reservoir 7 inside the droplet discharge head.

  As shown in FIG. 2 to be described later, a gap G that functions as a vibration space of the diaphragm 4 is formed between the diaphragm 4 and the individual electrode 8. 8 and the thickness of the diaphragm 4 (TEOS film 14). Since the width of the gap G greatly affects the ejection characteristics of the droplet ejection head, strict accuracy management is performed.

The nozzle plate 3 is composed of, for example, a silicon substrate having a thickness of about 180 μm, and is joined to the cavity plate 1 on the surface opposite to the electrode glass substrate 2 (upper surface in the case of FIG. 1). The nozzle plate 3 is formed with nozzle holes 12 for discharging liquid such as ink pressurized in the discharge chamber 5 as droplets. Further, a diaphragm 18 for absorbing pressure fluctuations of the liquid in the reservoir 7 is formed in a portion corresponding to the reservoir 7 of the cavity plate 1. Further, an orifice 6 for communicating the discharge chamber 5 and the reservoir 7 is also formed on the lower surface of the nozzle plate 3.
Here, the nozzle plate 3 is described as the upper side and the electrode glass substrate 2 is described as the lower side. However, in practice, the nozzle plate 3 is often used as the lower side than the electrode glass substrate 2.

  FIG. 2 is a diagram showing a schematic configuration of the right half droplet discharge head of FIG. In this embodiment, a high-concentration boron-doped layer that can be used as an electrode and can be used as an etching stop during etching is formed on a silicon substrate, and this is used as a diaphragm 4. The discharge chamber 5 provided with the vibration plate 4 on the bottom wall stores the liquid to be discharged from the nozzle hole 12, and is driven so that the vibration plate 4 serving as the bottom wall bends and displaces, whereby the pressure in the discharge chamber 5 is increased. And the droplets are ejected from the nozzle holes 12. The driving of the diaphragm 4 is performed by an electrostatic force generated by applying a voltage to the diaphragm 4 and the individual electrode 8. Therefore, the diaphragm 4 and the individual electrode 8 constitute an electrostatic actuator.

  The common electrode 19 of the cavity plate 1 is connected to the oscillation circuit 22 via a wire 23. The electrode terminal 11 of the electrode glass substrate 2 is also connected to the oscillation circuit 22 via a wire 23. Note that an electrode extraction opening 25 is formed through the portion corresponding to the electrode terminal 11 of the cavity plate 1, and the electrode terminal 11 is drawn out from the electrode extraction opening 25. The oscillation circuit 22 oscillates at, for example, 24 kHz, and supplies and stops charge by applying pulse potentials of 0 V and 30 V to the individual electrodes 8. That is, when the oscillation circuit 22 is driven to oscillate, for example, when an electric charge is supplied to the individual electrode 8 to be positively charged and the diaphragm 4 is relatively negatively charged, it is attracted to the individual electrode 8 by electrostatic force. Bend. As a result, the volume of the discharge chamber 5 increases. When the charge supply is stopped, the vibration plate 4 returns to the original state, but the volume of the discharge chamber 5 at that time also returns to the original state, so that the differential droplet 20 is discharged by the pressure. For example, printing such as printing is performed when the droplet 20 lands on a recording paper 21 to be recorded. Such a method is called pulling, but there is also a method called pushing that discharges droplets using a spring or the like.

  Further, a sealing material 26 that seals and seals the gap G from the outside air is deposited at the end of the gap G so as to prevent foreign matter, moisture (water vapor) and the like from entering the gap G, thereby forming a sealing portion. ing. The sealing portion deposits the sealing material 26 through a sealing opening 27 formed in the cavity plate 1 by a method such as CVD (Chemical Vapor Deposition), sputtering, or vapor deposition. It is formed by this. In addition to silicon oxide, for example, Al2O3 (aluminum oxide (alumina)), silicon nitride (SiN), silicon oxynitride (SiON), Ta2O5 (tantalum pentoxide), DLC (Diamond Like Carbon), Polypalaxylylene, PDMS (polydimethylsiloxane: a kind of silicone rubber), inorganic or organic compounds such as epoxy resin, etc., which have a relatively low molecular weight, can be deposited by vapor deposition, sputtering, etc., and are impermeable to moisture Can be used.

  In this example, the sealing opening 27 and the electrode extraction opening 25 are separate through holes, but may be a single through hole. When the sealing opening 27 is separated from the electrode extraction opening 25 as in this example, the sealing material 26 is selectively deposited only at a desired location and sealed. There exists an advantage which can form only as a sealing part efficiently.

  3A is a view of the electrode glass substrate 2 as viewed from above, and FIG. 3B is a cross-sectional view taken along the line AA of FIG. 3A and shows a cross section of the equipotential contact portion. Usually, the droplet discharge heads are made in units of wafers, and finally separated into each droplet discharge head (head chip). In the present embodiment, equipotential contacts are provided independently for each head chip, and are used to maintain the equipotential between the cavity plate 1 and the individual electrodes 8 during anodic bonding. About the part used as an equipotential contact, when forming the recessed part 9 in the electrode glass substrate 2, it leaves without etching. Then, ITO 0.1 μm, which is conductive, is formed together with the individual electrodes 8 thereon to form an ITO pattern 24. Therefore, the equipotential contact protrudes by 0.1 μm from the surface of the electrode glass substrate 2 by the amount of the ITO pattern 24. On the other hand, in the cavity plate 1, a portion of the TEOS film (0.1 μm) corresponding to the equipotential contact is removed, and a window exposing the silicon substrate (boron doped layer) which is the main material of the cavity plate 1 is formed. By contacting the silicon substrate and the ITO pattern 24 through this window, the equipotential between the individual electrode 8 electrically connected to the ITO pattern 24 and the silicon substrate is ensured at the time of anodic bonding.

  The air opening hole 31 communicates the outside of the droplet discharge head with the recess 9 to prevent the gap G formed by anodic bonding from being sealed. For example, the inside of the gap G is prevented from being pressurized by the generation of a gas such as oxygen due to heating to each substrate during anodic bonding or the like. The air opening hole 31 is formed by a sandblasting method, a cutting process, or the like. Further, since the air opening hole 31 is finally separated from the droplet discharge head by dicing, it does not remain in the completed droplet discharge head.

  The dicing line 30 is a line for separating a plurality of droplet discharge heads integrally formed on the wafer. Accordingly, the portions on the right side and the upper side of the dicing line 30 in FIG. 3 do not remain in the completed droplet discharge head. In the droplet discharge head shown in FIG. 3, only five members such as the individual electrodes 8 are described. However, in actuality, there are many nozzle holes 12 in one droplet discharge head. Corresponding individual electrodes 8 are formed.

  4 and 5 are diagrams showing a manufacturing process of the droplet discharge head according to the first embodiment. Hereinafter, the manufacturing method of the droplet discharge head will be described along the steps shown in FIGS.

(A) The electrode glass substrate 2 is produced here. First, for example, an electrode glass substrate having a thickness of about 1 mm is prepared, and a recess 9 having a depth of 0.2 μm is formed by etching on one surface thereof in accordance with the shape pattern of the individual electrode 8. As shown in FIG. 3B, the portion to be the equipotential contact is left without being etched. Here, the shape of the equipotential contact is not particularly limited as long as the silicon substrate of the cavity plate 1 and the individual electrode 8 can be brought into contact with each other to be equipotential. After the formation of the recess 9 and the equipotential contact, the individual electrode 8 and the ITO pattern 24 having a thickness of 0.1 μm are simultaneously formed by using, for example, a sputtering method. Finally, the liquid intake hole 13 and the air opening hole 31 are formed by sandblasting or cutting. Thereby, the electrode glass substrate 2 is produced.

(B) Next, one surface of a single crystal silicon substrate having a low oxygen concentration with a plane orientation of (110) is mirror-polished to produce a silicon substrate 41 having a thickness of about 220 μm, and the polished surface of the silicon substrate 41 Then, boron is diffused at a high concentration to form a boron doped layer 41a.
(C) Subsequently, a TEOS film (insulating film) 14 is formed by plasma CVD on the surface on which the boron doped layer 41a is formed. Further, a resist is applied to the surface of the formed TEOS film 14, and resist patterning (not shown) is performed for creating a window exposing silicon at an equipotential contact. Then, wet etching is performed with a hydrofluoric acid aqueous solution, and the TEOS film 14 is patterned to form windows as shown in FIG. Thereafter, the resist is peeled off.

(D) Then, the silicon substrate 41 and the electrode glass substrate 2 are anodically bonded to form a bonded substrate 42.
(E) Next, a TEOS etching mask (hereinafter referred to as a TEOS etching mask) 43 is formed on the surface of the bonding substrate 42 on the silicon substrate 41 side by a plasma CVD method. Further, resist patterning is performed on the TEOS etching mask 43 and the TEOS etching mask 43 is immersed in a hydrofluoric acid aqueous solution to form a portion 5a corresponding to the discharge chamber 5, a portion 25a corresponding to the electrode extraction opening 25, and a portion 27a corresponding to the sealing opening. This portion is etched until the TEOS etching mask 43 disappears. Thereafter, the resist is peeled off.

(F) Subsequently, resist patterning is performed in order to etch the TEOS etching mask 43 of the portion 7a serving as a reservoir. Then, the reservoir 7 is patterned by etching the TEOS etching mask 43 of those portions by 0.7 μm with a hydrofluoric acid aqueous solution. As a result, the thickness of the TEOS etching mask 43 remaining in the portion serving as the reservoir 7 becomes 0.3 μm. This is because the bottom surface of the reservoir 7 is finally thickened and the rigidity of the reservoir 7 is increased. Although the residual thickness of the TEOS etching mask 43 is 0.3 μm here, this thickness is adjusted according to the desired depth of the reservoir 7. Thereafter, the resist is peeled off.

(G) Next, the bonding substrate 42 is dipped in a 35 wt% potassium hydroxide aqueous solution, and the thickness of the discharge chamber 5, the portion 25 a serving as the electrode extraction opening and the portion 27 a serving as the sealing opening becomes about 10 μm. Wet etching is performed until. At this time, the reservoir 7 is masked and etching has not yet started.

(H) Subsequently, the bonding substrate 42 is immersed in a hydrofluoric acid aqueous solution to remove the TEOS etching mask 43 in the portion serving as the reservoir 7, and the bonding substrate 42 is immersed in a 3 wt% potassium hydroxide aqueous solution to form a boron doped layer 41a. Etching is continued until it is determined that the etching stop is sufficiently effective. Thereby, the portion to be the reservoir 7 is also etched to form the reservoir 7.

(I) When the wet etching is completed, the bonding substrate 42 is immersed in a hydrofluoric acid aqueous solution, the TEOS etching mask 43 on the surface of the silicon substrate 41 is peeled off, and the liquid intake hole 13 is penetrated to the reservoir 7.

(J) Next, in order to remove the residual silicon in the portion that becomes the electrode extraction opening 25 and the portion that becomes the sealing opening 27 of the silicon substrate 41, the mask substrate 50 is bonded to the surface of the bonding substrate 42 on the silicon substrate 41 side. Adhere to. Then, for example, RIE dry etching (anisotropic dry etching) is performed for 1 hour under the conditions of an RF power of 200 W, a pressure of 40 Pa (0.3 Torr), and a CF 4 flow rate of 30 cm 3 / min (30 sccm) to form the electrode extraction opening 25. Opening is performed by applying plasma only to the portion and the portion to be the opening 27 for sealing. This opening also opens the gap G between the individual electrode 8 and the silicon substrate 41 to the atmosphere.

  Here, the present invention is characterized in that the mask substrate 50 and the silicon substrate 41 are attached by vacuum suction in order to improve the adhesion between the mask substrate 50 and the silicon substrate 41 of the bonding substrate 42. The characteristic part will be described in detail.

6A and 6B are explanatory views of the characterizing portion of the present invention. FIG. 6A is a plan view of the mask substrate, FIG. 6B is a schematic cross-sectional view of an apparatus for vacuum suction using the mask substrate, and FIG. (C) is an enlarged view of a dotted line A portion of FIG. 6 (b).
The mask substrate 50 has an electrode extraction hole 51 corresponding to the electrode extraction opening 25 of the cavity plate 1 and a sealing hole 52 corresponding to the sealing opening 27. That is, it has a processing through hole corresponding to a portion for processing the silicon substrate 41. A suction cup recess 53 for forming a vacuum holding space between the bonding substrate 42 and the silicon substrate 41 is formed on the side where the bonding substrate 42 is attached to the silicon substrate 41. The suction cup recess 53 has an area as much as possible in order to have a function as a suction cup. The suction cup recess 53 is formed at a position communicating with the liquid intake hole 13 of the bonding substrate 42. Further, in the mask substrate 50, suction cup recesses 54 are also formed in regions where head chips are not formed. A through hole (not shown) is also formed in a region of the bonding substrate 42 corresponding to the formation region of the suction cup recess 54. Further, a pin alignment hole 50a used for pin alignment with the bonding substrate 42 is formed.

  When the mask substrate 50 thus configured is attached to the bonding substrate 42 by vacuum suction, first, as shown in FIG. 6B, the entire surface of the bonding substrate 42 on the electrode glass substrate side is subjected to heat resistance and resistance. A highly corrosive tape 60 is applied to close a through hole (a through hole (not shown) provided corresponding to the liquid intake hole 13, the air release hole 31, and the suction cup recess 54) formed in the bonding substrate 42. . Then, the mask substrate 50 and the bonding substrate 42 are positioned by pin alignment or the like, brought into contact with each other, and put into the vacuum box 70. Then, the vacuum box 70 is gradually evacuated using the vacuum pump 80. Thereby, the space in the suction cup recesses 53 and 54 is gradually reduced, and the inside of the vacuum box 70 is suddenly opened to the atmosphere. Thereby, the space in the suction cup recessed parts 53 and 54 is left in the pressure-reduced state. As a result, the mask substrate 50 and the bonding substrate 42 are in close contact with each other by vacuum suction. Note that the mask substrate 50 of FIG. 6 is provided with a suction cup recess 53 for each effective area corresponding to a nozzle row (see FIG. 1) (formation regions of a plurality of discharge chambers 5 and reservoirs 7 communicating with the nozzle row). However, only the formation region of the reservoir 7 may be used. Further, instead of the mask substrate 50, as shown in FIG. 7, a mask substrate 50A provided with a counterbore portion 55, which is a common concave portion, in an effective area of adjacent nozzle rows may be used. When this mask substrate 50A is used, contact damage can be prevented from being applied to the portion where the discharge chamber 5 is formed due to the contact between the silicon substrate 41 and the mask substrate 50A. 7 is a plan view of the mask substrate (FIG. 7A), a schematic cross-sectional view of the apparatus for vacuum suction using the mask substrate (FIG. 7B), and FIG. The enlarged view (FIG.7 (c)) of the dotted-line A part of (b) is shown.

  As described above, the mask substrate 50 and the bonding substrate 42 are brought into close contact with each other, and RIE dry etching is performed as described above to form the electrode extraction opening 25 and the sealing opening 27. Thus, since dry etching is performed after improving the adhesion between the mask substrate 50 and the bonding substrate 42, the etching gas can be prevented from flowing between the mask substrate 50 and the bonding substrate 42, and the portion that should be protected originally Can be reliably protected, and only the target portion can be etched. Thereafter, the tape attached to the electrode glass substrate 2 is peeled off. Thereby, the mask substrate 50 and the bonding substrate 42 are detached.

Returning to the description of FIG.
(K) A mask substrate 50B in which a sealing hole 52 is formed in a portion corresponding to the sealing opening 27 is brought into close contact with the surface of the bonding substrate 42 on the silicon substrate 41 side, and the sealing hole 52 and silicon of the mask substrate 50B A sealing material 26 is deposited by plasma CVD through the sealing opening 27 of the substrate 41 to seal the end of the gap G. Similarly to the previous mask substrate 50, the mask substrate 50B used here also has a processing through hole corresponding to a portion for processing the silicon substrate 41 (here, the sealing hole 52 corresponding to the sealing opening 27). In addition, a suction cup recess 53a is formed, and the silicon substrate 41 is brought into close contact with the same procedure as described above. Thereby, it can suppress that film-forming gas wraps around between the silicon substrate 41 and the mask substrate 50B.

(L) Thereafter, the nozzle plate 3 in which the nozzle holes 12 are formed in advance is bonded to the cavity plate 1 side of the bonding substrate 42 with, for example, an epoxy adhesive.
(M) Finally, dicing is performed along the dicing line 30 (see FIG. 3) to cut into individual droplet discharge heads, thereby completing the droplet discharge heads. Here, the individual electrodes 8 that have been short-circuited at the time of anodic bonding are divided and independent for each nozzle hole 12. Further, the air opening hole 31 and the glass groove communicating therewith are also cut.

  As described above, according to the first embodiment, since the mask substrate 50 (or the mask substrate 50B) and the bonding substrate 42 are attached by vacuum suction, the adhesion can be improved, and an etching gas or film formation can be achieved. Gas wraparound can be prevented. Therefore, it is possible to reliably protect the portion that should be protected, and it is possible to perform the target process only on the target portion, and it is possible to efficiently manufacture a highly reliable electrostatic actuator.

  Further, when the mask substrate 50 (or mask substrate 50B) and the bonding substrate 42 are detached, the tape attached to the electrode glass substrate 2 may be peeled off, so that workability is good. In addition, since the liquid intake hole 13 is used as an air communication hole of the suction cup recess 53 by peeling the tape, there is no need to newly form a through hole for simple separation of vacuum suction. In addition, in this example, although the through-hole is newly provided corresponding to the suction cup recessed part 54, it is not necessarily required.

  Further, when the mask substrate 50A provided with the counterbore 55 is used, it is possible to prevent contact damage to the formation portion of the discharge chamber 5 due to contact between the silicon substrate 41 and the mask substrate 50A.

Embodiment 2
FIG. 8 is a schematic configuration diagram of a droplet discharge apparatus using the droplet discharge head manufactured in the above embodiment. The droplet discharge device shown in FIG. 8 is a printer intended for printing by an inkjet method. In FIG. 8, a drum 101 that supports a printing paper 110 that is a printing object and a droplet discharge head 102 that discharges ink onto the printing paper 110 and performs recording are mainly configured. Although not shown, there is an ink supply means for supplying ink to the droplet discharge head 102. The print paper 110 is held by being pressed against the drum 101 by a paper press roller 103 provided parallel to the axial direction of the drum 101. A feed screw 104 is provided parallel to the axial direction of the drum 101, and the droplet discharge head 102 is held. As the feed screw 104 rotates, the droplet discharge head 102 moves in the axial direction of the drum 101.

  On the other hand, the drum 101 is rotationally driven by a motor 106 via a belt 105 or the like. Further, the print control unit 107 drives the feed screw 104 and the motor 106 based on the print data and the control signal, and although not shown here, drives the oscillation drive circuit to vibrate the diaphragm 4, Printing is performed on the print paper 110 while controlling.

  Here, the liquid is ejected onto the print paper 110 as ink, but the liquid ejected from the droplet ejection head is not limited to ink. For example, in an application to be discharged onto a substrate to be a color filter, a liquid containing a pigment for a color filter, a liquid containing a compound to be a light emitting element in an application to be discharged onto a display substrate such as an organic EL, and wiring on the substrate In application, for example, a liquid containing a conductive metal may be discharged from a droplet discharge head provided in each apparatus. In addition, when the droplet discharge head is used as a dispenser and is used for discharging onto a substrate that is a microarray of biomolecules, DNA (Deoxyribo Nucleic Acids: deoxyribonucleic acid), other nucleic acids (for example, Ribo Nucleic Acid: ribonucleic acid, Peptide (Nucleic Acids: peptide nucleic acids, etc.) A liquid containing a probe such as a protein may be discharged. In addition, it can also be used for discharging dyes such as cloth.

FIG. 3 is an exploded view of the droplet discharge head according to the first embodiment. Sectional drawing of the part which cleaved the part of the discharge chamber in the longitudinal direction. The figure which looked at the electrode glass substrate which comprises the droplet discharge head of FIG. 1 from the upper surface, and the fragmentary sectional view (b) of an equipotential contact part. FIG. 4 is a manufacturing process diagram of the droplet discharge head according to the first embodiment. FIG. 5 is a manufacturing process diagram of the droplet discharge head following FIG. 4. The top view (a) of a mask board | substrate, apparatus schematic explanatory sectional drawing (b) for vacuum suction using a mask board | substrate, The enlarged view (c) of the dotted-line A part of FIG.6 (b). The top view (a) of a mask board | substrate, apparatus schematic explanatory sectional drawing (b) for vacuum suction using a mask board | substrate, The enlarged view (c) of the dotted-line A part of FIG.6 (b). FIG. 2 is a schematic configuration diagram of a droplet discharge device including the droplet discharge head according to the first embodiment.

Explanation of symbols

1 cavity plate, 2 electrode glass substrate, 3 nozzle plate, 4 diaphragm, 5 discharge chamber, 6 orifice, 7 reservoir, 8 individual electrode, 9 recess, 10 lead part, 11 electrode terminal, 12 nozzle hole, 13 liquid intake hole , 14 TEOS film, 15 Liquid protective film, 18 Diaphragm, 19 Common electrode, 20 Liquid droplet, 21 Recording paper, 22 Oscillator circuit, 23 Wire, 24 pattern, 25 Electrode extraction opening, 26 Sealing material, 27 For sealing Opening, 5a Portion corresponding to discharge chamber, 25a Portion corresponding to electrode extraction opening, 27a Portion corresponding to sealing opening, 30 Dicing line, 31 Air opening hole, 41 Silicon substrate, 41a Boron doped layer, 42 Bonding substrate 43 Etching mask 50 Mask substrate 50a Pin alignment hole 50A Mask substrate 51 Electrode extraction hole, 52 Sealing hole, 53, 54 Suction cup recess, 55 Counterbore part, 60 Tape, 70 Vacuum box, 80 Vacuum pump, 101 Drum, 102 Droplet discharge head, 103 Paper pressure roller, 104 Feed screw, 105 Belt , 106 Motor, 107 Print control means, 110 Print paper

Claims (10)

An electrode glass substrate on which individual electrodes are formed and a silicon substrate on which a diaphragm that operates by electrostatic force generated between the individual electrodes is opposed to the individual electrodes and the diaphragm with a gap therebetween. A method for manufacturing an electrostatic actuator, comprising: a bonding step for bonding in such a manner; and a processing step for selectively performing a predetermined process on a part of the silicon substrate of the bonding substrate formed in the bonding step,
In the processing step, a mask substrate having a processing through hole in a portion corresponding to the processing portion for performing the predetermined processing and a recess for forming a vacuum holding space with the silicon substrate is provided. An electrostatic actuator comprising: an adhesion step of attaching and closely contacting the silicon substrate by vacuum suction; and a step of performing the predetermined treatment on the silicon substrate through the processing through hole of the mask substrate. Manufacturing method.   After the mask substrate is positioned and brought into contact with the bonding substrate, it is put into a vacuum box, and the inside of the vacuum box is gradually evacuated and then suddenly released to the atmosphere to vacuum the mask substrate and the bonding substrate. The method for manufacturing an electrostatic actuator according to claim 1, wherein the electrostatic actuator is adsorbed.   The predetermined treatment is performed by dry etching through a sealing opening for forming a sealing portion for sealing the gap and an electrode extraction opening for taking out the individual electrode to the outside in the silicon substrate. The method for manufacturing an electrostatic actuator according to claim 1, wherein the process is a forming process.   The said predetermined process is a process which deposits a sealing material through the said opening for sealing of the said silicon substrate, and forms the sealing part which seals the said gap. The manufacturing method of the electrostatic actuator in any one of Claim 3.   5. The method of manufacturing an electrostatic actuator according to claim 4, wherein the sealing material is deposited by a CVD method.   The method for manufacturing an electrostatic actuator according to claim 4, wherein the sealing material is deposited by a sputtering method.   The concave portion is provided in the mask substrate so as to communicate with a through-hole penetrating the electrode glass substrate and the silicon substrate, and in the adhesion step, a tape is attached to the surface of the electrode glass substrate of the bonding substrate. In this state, the mask substrate is attached to the silicon substrate by vacuum suction, and the tape substrate is peeled off when the mask substrate and the bonding substrate are detached. The method for manufacturing an electrostatic actuator according to claim 1, wherein the method is performed.   A method for manufacturing a droplet discharge head, wherein the method for manufacturing an electrostatic actuator according to any one of claims 1 to 7 is applied to manufacture a droplet discharge head.   A droplet discharge head is manufactured by applying the method for manufacturing an electrostatic actuator according to claim 7, wherein the through hole is a liquid intake hole for taking a discharge liquid into the droplet discharge head from the outside. A method for manufacturing a droplet discharge head. A method for manufacturing a droplet discharge device, wherein the droplet discharge device is manufactured by applying the method for manufacturing a droplet discharge head according to claim 8.

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