JP2007276127A - Method for manufacturing electrostatic actuator, method for manufacturing liquid droplet discharge head, method for manufacturing liquid droplet discharge apparatus, mask substrate, and method for manufacturing mask substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose a method for manufacturing an electrostatic actuator capable of improving the efficiency of a sealing operation of a gap between electrodes, and to provide a mask substrate facilitating the method. <P>SOLUTION: The method comprises a process wherein a through-channel 26 for providing a sealing material 25 blocking the gap 40 from the open air and a plurality of positioning holes 24 are formed in a cavity substrate 20 of a joint body jointed with an electrode substrate 10 having an individual electrode 12 and the cavity substrate 20 having a vibrating plate 22 opposing the individual electrode 12 through the gap 40 and operated by an electrostatic force generated between the individual electrode 12 and it, a process wherein a first mask substrate 60 comprising a silicon substrate and in which an opening 61 and a plurality of pillar-shaped projecting parts 62 are respectively formed at positions corresponding to the through-channel 26 and the positioning holes 24 of the cavity substrate 20, is tightly laminated on the cavity substrate 20 by inserting the pillar-shaped projecting parts 62 into the positioning holes 24 of the cavity substrate 20, and a process wherein a sealing material 25 is piled in the through-channel 26 through the opening 61 of the first mask substrate 60 to seal the gap 40. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrostatic actuator in which a movable part is displaced by an electrostatic force, a droplet discharge head to which the electrostatic actuator is applied, methods for manufacturing a droplet discharge device, and a mask substrate used in those methods.

  As a droplet discharge method for printers, etc., the bottom wall is equipped with a discharge chamber for storing discharge liquid composed of movable electrodes, the bottom wall is deformed to increase the pressure in the discharge chamber, and droplets are discharged from the communicating nozzle. There is a method of discharging. In this case, as a method of displacing the bottom wall (diaphragm) serving as the movable electrode, an electrostatic actuator is configured in which the diaphragm and the counter electrode (fixed electrode) are opposed via a gap, and a voltage is generated between them. An electrostatic drive system that generates a voltage by applying the above is widely known.

In the electrostatic actuator as described above or a droplet discharge head using the same, when water or the like adheres to at least one surface between the movable electrode and the fixed electrode, polar molecules such as water are charged. There is a possibility that the electrostatic attraction characteristic may be deteriorated. Furthermore, polar molecules may hydrogen bond with each other, and the movable electrode may stick to the fixed electrode, making it inoperable. Therefore, it is desirable to block the gap between the opposed surfaces of the movable electrode and the fixed electrode from the outside air. The gap can be almost closed by bonding the movable electrode substrate and the fixed electrode substrate, but if the gap is completely closed, power (charge) cannot be supplied to the electrode from the outside. For this reason, an opening for taking out the electrode is provided in a part, and the opening is used to secure electrical connection with the outside, and the opening is closed with a sealing material of another member for airtight sealing. Intrusion of moisture and the like is prevented (see, for example, Patent Document 1).
JP 2002-1972

  As described above, when airtight sealing is performed by sealing the opening portion with a sealing material, for example, in the process of formation, the sealing material originally does not require sealing, for example, is bonded to another substrate. If it adheres to the portion or the terminal portion of the extracted electrode, it becomes an obstacle to bonding or electrical connection with another substrate, causing bonding failure or connection failure. Therefore, in order to prevent these defects, it is necessary to further perform a process of removing excess sealing material. In such a removal process, the sealing material is scraped off or washed, which increases the possibility of generation of foreign matters such as dust, and reduces the productivity of the sealing work.

  The present invention has been made in order to cope with the above problems, and an electrostatic actuator that does not require a sealing material removal step and that can improve the efficiency of sealing the gap between electrodes, It is an object of the present invention to provide each manufacturing method of a droplet discharge head and a droplet discharge device. In addition, another object is to propose a mask substrate that allows the method to be easily performed.

  The method for manufacturing an electrostatic actuator according to the present invention includes: a first substrate having a fixed electrode; and a movable electrode that is opposed to the fixed electrode through a gap and operates by electrostatic force generated between the fixed electrode. Forming a through groove and a plurality of positioning holes for disposing a sealing material for blocking the gap from outside air in the second substrate of the joined body joined to the second substrate having silicon; and silicon A first mask substrate comprising a substrate and having openings and a plurality of columnar convex portions respectively formed at positions corresponding to the through-grooves and positioning holes of the second substrate is defined as positioning holes of the second substrate. Inserting the columnar convex portion of the first mask substrate into the second substrate and laminating the first mask substrate on the second substrate; and depositing the sealing material in the through groove through the opening of the first mask substrate. A step of sealing .

  According to the above method, when the gap is sealed, the alignment between the first mask substrate and the second substrate can be performed using the columnar protrusions formed on the first mask substrate. Positioning can be easily performed without using a separate jig from the substrate. Further, since the sealing material is deposited in the through groove through the opening of the first mask substrate, the sealing material can be efficiently deposited at a desired site. Therefore, it is possible to prevent adhesion of the fixed electrode to which the sealing material should not be attached to the contact point between the external power supply means and the prevention of poor connection and long life by reliable sealing. Can do.

Another method of manufacturing an electrostatic actuator according to the present invention is a movable substrate that is operated by electrostatic force generated between a first substrate having a fixed electrode and the fixed electrode that faces the fixed electrode through a gap. Forming a through groove and a plurality of positioning holes for disposing a sealing material for blocking the gap from outside air on the second substrate of the joined body joined to the second substrate having an electrode; A plurality of positioning holes for positioning the second mask substrate, each formed with an opening and a plurality of columnar protrusions at positions corresponding to the through grooves and the positioning holes of the second substrate. A step of laminating the formed first mask substrate on the second substrate by inserting the columnar convex portions of the first mask substrate into the positioning holes of the second substrate, and a silicon substrate; Said first mask A second mask substrate having an opening and a plurality of columnar protrusions formed at positions corresponding to the opening and the positioning hole of the plate, respectively, and the columnar protrusion of the second mask substrate in the positioning hole of the first mask substrate. A step of inserting and sealing and stacking the sealing material on the through-groove through the openings of the first and second mask substrates, and a step of sealing the gap Is provided.
Also in this method, the effects as described above can be obtained. In addition to this, the two mask substrates on which the columnar protrusions for alignment are formed are overlapped, so that the sealing material is not deposited on the lower first mask substrate, which is caused by the deposition of the sealing material. This makes it difficult for warping to occur. For this reason, the wraparound of the sealing material between the first mask substrate and the second substrate is suppressed, and more reliable sealing at a desired position is possible.

A method for manufacturing a droplet discharge head according to the present invention is a method for applying an electrostatic actuator manufacturing method according to any one of the above to form an electrostatic actuator and storing and discharging droplets on the second substrate. A flow path that becomes a chamber is formed.
In addition, a method for manufacturing a droplet discharge device according to the present invention is a method in which a droplet discharge head is manufactured by the method for manufacturing a droplet discharge head, and the manufactured droplet discharge head is incorporated.
According to these droplet discharge heads and droplet discharge devices, the sealing material can be deposited only on the target sealing portion, so that the sealing material to the contact point between the fixed electrode and the external power supply means Connection failure due to adhesion can be prevented, and it is possible to contribute to a long life by reliable sealing.

  The mask substrate of the present invention is a mask substrate made of a silicon substrate and having openings for depositing or depositing a member on a predetermined portion of the workpiece, and a plurality of columnar shapes for positioning with respect to the workpiece. Protrusions are provided. According to this, by providing the positioning holes corresponding to the columnar convex portions of the mask substrate in the workpiece, alignment can be easily performed only with the mask substrate and the workpiece.

The mask substrate manufacturing method according to the present invention is a mask substrate manufacturing method used when a member is formed or deposited on a predetermined portion of a workpiece, and the silicon substrate is subjected to anisotropic wet etching to perform the above-described processing. An opening for depositing or depositing a member on a predetermined portion of the workpiece is formed, and dry etching or wet etching is performed on the silicon substrate to form a plurality of columnar protrusions for positioning with respect to the workpiece. Is.
According to this, since the columnar convex portions formed on the mask substrate are formed by photolithography and etching, the dimensional accuracy is very high, and the alignment accuracy using this can be very high. In addition, this makes it possible to simultaneously form a plurality of positioning columnar convex portions on the mask substrate.

Embodiment 1
(Structure of droplet discharge head)
FIG. 1 is an exploded perspective view showing a part of a droplet discharge head according to Embodiment 1 of the present invention. In the present embodiment, a face eject type liquid droplet ejection head will be described as a representative device using an electrostatic actuator driven by an electrostatic system.
As shown in FIG. 1, the droplet discharge head according to this embodiment includes three substrates: an electrode substrate 10 that is a first substrate, a cavity substrate 20 that is a second substrate, and a nozzle substrate 30 that is a third substrate. Are sequentially laminated and joined.

  The electrode substrate 10 is mainly made of a substrate such as borosilicate heat-resistant hard glass having a thickness of about 1 mm. A plurality of electrode formation grooves 11 having a depth of, for example, about 0.3 μm are formed on the surface of the electrode substrate 10 in accordance with a region to be a discharge chamber 21 of the cavity substrate 20 described later. Inside the electrode forming groove 11, an individual electrode 12 serving as a fixed electrode is provided so as to face the bottom wall of each discharge chamber 21 of the cavity substrate 20, and a lead portion 13 and a terminal portion 14 are provided integrally. It has been. Hereinafter, unless specifically distinguished, the individual electrode 12 including the lead portion 13 and the terminal portion 14 will be described. A gap 40 (see FIG. 2) serving as a vibration space of the diaphragm 22 is formed between the diaphragm 22 and the individual electrode 12 due to the electrode forming groove 11. The individual electrode 12 is formed by depositing ITO (Indium Tin Oxide) with a thickness of 0.1 μm inside the electrode formation groove 11 by sputtering, for example. Further, the electrode substrate 10 is provided with a liquid inlet 15 serving as a flow path for taking in liquid supplied from an external tank (not shown).

The cavity substrate 20 is made of, for example, a silicon single crystal substrate (hereinafter referred to as a silicon substrate) having a plane orientation (100). The cavity substrate 20 is provided with a recess (a bottom wall is a movable electrode diaphragm 22 facing the individual electrode 12) serving as a discharge chamber 21 for temporarily storing a liquid to be discharged, and a sealing material 25 described later. A through groove 26 is formed in the portion directly above the lead portion 13 to form a sealing portion. Further, on the surface of the cavity substrate 20 facing the electrode substrate 10, an insulating film for electrically insulating between the diaphragm 22 and the individual electrode 12 (SiO _{2 formed} using tetraethoxysilane (ethyl silicate)) can be used. The TEOS film is formed to a thickness of 0.1 μm using a plasma CVD method. The insulating film 23 may be made of Al ₂ O ₃ (aluminum oxide) or the like. In addition, a recess serving as a reservoir 28 for storing the liquid supplied to each discharge chamber 21 is also formed. Furthermore, a common electrode terminal 27 is provided which serves as a terminal for supplying a charge having a polarity opposite to that of the individual electrode 12 to the diaphragm 22 from an external power supply means (not shown).

  The nozzle substrate 30 is made of, for example, a silicon substrate, and a plurality of nozzle holes 31 are formed. Each nozzle hole 31 discharges liquid pressurized by driving the diaphragm 22 to the outside as droplets. In addition, the nozzle substrate 30 is formed with an orifice 29 for communicating the discharge chamber 21 and the reservoir 28, and a diaphragm 32 for buffering pressure applied in the direction of the reservoir 28 when the diaphragm 22 is bent.

  FIG. 2 is a cross-sectional view along the longitudinal direction of the individual electrode 12 of the 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 the diaphragm 22. The discharge chamber 21 provided with the vibration plate 22 on the bottom wall stores the liquid to be discharged from the nozzle hole 31, and is driven so that the vibration plate 22 serving as the bottom wall bends and displaces. And the droplets are ejected from the nozzle holes 31. The driving of the diaphragm 22 is performed by an electrostatic force generated by applying a voltage to the diaphragm 22 and the individual electrode 12. Therefore, the diaphragm 22 and the individual electrode 12 constitute an electrostatic actuator.

The oscillation drive circuit 41 is connected to the terminal portion 14 of the electrode outlet 44 and the common electrode terminal 27 of the cavity substrate 20 via a wiring 42 such as an FPC (Flexible Print Circuit), and performs supply control of the applied voltage. . The oscillation drive circuit 41 oscillates at 24 kHz, for example, and supplies electric charges by applying pulse potentials of 0 V and 30 V to the individual electrodes 12. When the oscillation drive circuit 41 is driven to oscillate, for example, when an electric charge is supplied to the individual electrode 12 to be positively charged and the vibration plate 22 is relatively negatively charged, the vibration is attracted to the individual electrode 12 by the electrostatic force and bent. Mu This increases the volume of the discharge chamber 21. When the supply of electric charge is stopped, the diaphragm 22 returns to its original state, but the volume of the discharge chamber 21 at that time also returns to its original state, and a differential droplet is discharged by the pressure. Recording such as printing is performed when the droplets land on a recording sheet to be recorded, for example.
In order to prevent foreign matter, moisture (water vapor) and the like from entering the gap 40 and seal the gap 40 from the outside air, a through groove 26 is provided between the electrodes of the electrode substrate 10 and the cavity substrate 20. The sealing material 25 is disposed.

  FIG. 3 is a plan view showing the cavity substrate 20 stacked on the electrode substrate 10. As shown in FIG. 3, the cavity substrate 20 is provided with a through groove 26 that exposes the lead portion 13 of the electrode substrate 10. Further, the terminal portion 14 of the electrode substrate 10 is in a state of being released from the cavity substrate 20 by the electrode outlet 44 where the cavity substrate 20 is cut out.

The gap 40 is sealed by CVD (Chemical Vapor Deposition), sputtering, vapor deposition, or the like, from the opening of the through groove 26, silicon oxide (SiO ₂ ), which is the sealing material 25, or the like. This is performed by depositing on the lead portion 13 portion of the electrode substrate 10. As the sealing material 25, in addition to silicon oxide, for example, Al ₂ O ₃ (aluminum oxide (alumina)), silicon nitride (SiN), silicon oxynitride (SiON), Ta ₂ O ₅ (tantalum pentoxide), DLC (Diamond Like Carbon), polypalaxylylene, PDMS (polydimethylsiloxane: a kind of silicone rubber), epoxy resin, etc., which have a relatively small molecular weight and can be deposited by vapor deposition, sputtering, etc., and are impermeable to moisture Is preferably used.

  By the way, if the sealing material 25 is deposited at a portion where the sealing material 25 should not be deposited, for example, at a connection portion between the terminal portion 14 and the wiring 42, the terminal portion 14 and the wiring 42 are electrically improved. There is a possibility that connection failure (connection failure) may occur. Therefore, in the present embodiment, the through groove 26 is used so that the sealing material 25 can be selectively deposited and sealed only at a desired location, and only a necessary location can be efficiently formed as a sealing portion. . Then, a mask (described later) having an opening corresponding to the through groove 26 is laminated on the cavity substrate 20, and the sealing material 25 is basically deposited only on the through groove 26 (directly above the lead portion 13). Have taken. This will be described in detail in connection with the description of the manufacturing method of the droplet discharge head.

(Method for manufacturing droplet discharge head)
4 and 5 are process diagrams illustrating a method for manufacturing a droplet discharge head according to the first embodiment. Here, a method for manufacturing a droplet discharge head will be described with reference to FIGS. 4 and 5A to 5I.
In practice, a plurality of droplet discharge head members are simultaneously formed for each wafer. FIGS. 4 and 5 show one unit of the droplet discharge head.

(A) First, one surface of the silicon substrate (silicon wafer) 51 (becomes a bonding surface with the electrode substrate 10) is mirror-polished to produce a substrate having a thickness of 220 μm (to be the cavity substrate 20), for example.
Next, the polished surface of the silicon substrate 51 is opposed to a solid diffusion source containing B ₂ O ₃ as a main component, and is placed in a vertical furnace to diffuse boron into the silicon substrate 51 to form a boron doped layer 52. To do. Then, on the surface on which the boron doped layer 52 is formed, a processing temperature of 360 ° C., a high frequency output of 250 W, a pressure of 66.7 Pa (0.5 Torr), a TEOS flow rate of 100 cm ³ / min (100 sccm), and an oxygen flow rate of 1000 cm ³ / Under the condition of min (1000 sccm), the TEOS insulating film 23 is formed to a thickness of 0.1 μm.

On the other hand, the electrode substrate 10 is manufactured in a separate process from the above (a). For example, etching or the like is performed on one surface of a glass substrate of about 1 mm to form the electrode formation groove 11 having a depth of about 0.3 μm. After the formation of the electrode forming groove 11, the individual electrode 12 having a thickness of 0.1 μm is simultaneously formed in the groove 11 by using, for example, a sputtering method. Finally, a liquid intake port 15 that communicates with the reservoir and a through-hole 16 that receives a columnar convex portion of the mask substrate, which will be described later, are formed by sandblasting or cutting.
(B) After heating the silicon substrate 51 and the electrode substrate 10 to 360 ° C., a negative electrode is connected to the electrode substrate 10 and a positive electrode is connected to the silicon substrate 51, and a voltage of 800V is applied to anodic bond them. As a result, the silicon substrate 51 and the electrode substrate 10 become a bonded substrate (or bonded body) 50 laminated via the gap 40.

(C) Next, the surface of the bonding substrate 50 is ground until the silicon substrate 51 has a thickness of about 60 μm. Thereafter, in order to remove the work-affected layer, the silicon substrate 51 is subjected to about 10 μm anisotropic wet etching (hereinafter referred to as wet etching) with a potassium hydroxide aqueous solution. As a result, the thickness of the silicon substrate 51 is reduced to about 50 μm.

(D) A silicon oxide hard mask (hereinafter referred to as TEOS hard mask) 53 by TEOS is formed on the surface of the bonding substrate 50 on which wet etching has been performed by plasma CVD. As the film formation conditions, for example, the processing temperature during film formation is 360 ° C., the high frequency output is 700 W, the pressure is 33.3 Pa (0.25 Torr), the TEOS flow rate is 100 cm ³ / min (100 sccm), and the oxygen flow rate is 1000 cm ³ / min (1000 sccm). Under the conditions, a film having a thickness of 1.5 μm is formed. Film formation by the plasma CVD method using TEOS can be performed at a relatively low temperature, and heating of the substrate can be suppressed.

(E) After the TEOS hard mask 53 is formed, resist patterning is performed in order to etch the TEOS hard mask 53 in the portions that become the discharge chamber 21, the reservoir 28, the through groove 26, the positioning hole 24, and the electrode outlet 44. Then, the TEOS hard mask 53 is etched using a hydrofluoric acid aqueous solution, and the TEOS hard mask 53 is patterned. Then, after etching, the resist is peeled off.

(F) Next, the bonding substrate 50 is dipped in a 35 wt% potassium hydroxide aqueous solution so that the thickness of the portions that become the discharge chamber 21, the reservoir 28, the through groove 26, the positioning hole 24, and the electrode outlet 44 is about 10 μm. Anisotropic wet etching (hereinafter referred to as wet etching) is performed until this is achieved. Further, the bonding substrate 50 is immersed in a 3 wt% potassium hydroxide aqueous solution, and the wet doping is continued until it is determined that the etching stop where the boron dope layer 52 is exposed and the etching progresses extremely slowly is effective. In this way, by performing etching using two types of potassium hydroxide aqueous solutions having different concentrations, it is possible to suppress surface roughness of the diaphragm 22 formed in the portion serving as the discharge chamber 21 and to increase the thickness accuracy. As a result, the discharge performance of the droplet discharge head can be stabilized.

(G) After completion of the wet etching, the TEOS hard mask 53 on the surface of the silicon substrate 51 is peeled off using a hydrofluoric acid aqueous solution. Then, in order to remove the portion of the boron doped layer 52 that becomes the through groove 26, the positioning hole 24, and the electrode outlet 44, an etching mask having an opening corresponding to those portions is attached to the surface of the silicon substrate 51 of the bonding substrate 50. Then, for example, RIE dry etching is performed for about 30 minutes 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), and the through grooves 26, the positioning holes 24, and the electrode outlets Plasma is applied to the portion 44 to penetrate the silicon substrate 51. As a result, the through groove 26 communicates with the gap 40.

Subsequently, the gap 40 formed between the cavity substrate 20 (silicon substrate 51 on which the flow path is formed) and the electrode formation groove 11 of the electrode substrate 10 is sealed. This sealing is performed using a first mask substrate 60 prepared in advance. The first mask substrate 60 is made of a silicon substrate, and has openings 61 and a plurality of columnar protrusions 62 formed at positions corresponding to the through grooves 26 and the positioning holes 24 of the cavity substrate 20. The columnar protrusion 62 is shaped to fit into the positioning hole 24 of the cavity substrate 20.
(H) Using the first mask substrate 60, the columnar convex portions 62 are inserted and fitted into the positioning holes 24 of the cavity substrate 20, and the first mask substrate 60 is brought into close contact with the surface (top surface) of the cavity substrate 20. Laminate. As a result, the portion of the through groove 26 of the cavity substrate 20 is exposed through the opening 61 of the first mask substrate 60, while the other portion of the cavity substrate 20 is covered with the first mask substrate 60. Here, the outer peripheral portions of the bonding substrate 50 and the first mask substrate 60 may be fixed to each other with a jig or the like interposed therebetween. At this time, it is preferable that the space serving as the discharge chamber 21 and the space serving as the reservoir 28 are opened to the atmosphere by the atmosphere opening groove.
Then, the bonding substrate 50 on which the first mask substrate 60 is closely stacked is put into a CVD apparatus, and, for example, SiO ₂ is formed as the sealing material 25. At this time, the sealing material 25 is selectively deposited only in the through groove 26 by the first mask substrate 60, and the gap 40 formed between the individual electrode 12 and the diaphragm 22 is sealed.

(I) After the above sealing process, the first mask substrate 60 is removed from the bonding substrate 50. Then, for example, sputtering is performed using platinum (Pt) as a target, and the common electrode terminal 27 is formed. Further, the nozzle substrate 30 separately manufactured is bonded and bonded to the cavity substrate 20 of the bonding substrate 50. Thereafter, dicing is performed along the dicing line, and the liquid droplet ejection head is cut into individual liquid droplet ejection heads to complete the liquid droplet ejection head. Finally, the terminal portion 14 of the individual electrode 12 is bonded using an anisotropic conductive adhesive (ACF) such as a flexible printed circuit (FPC) on which a driver IC is mounted.
4 and 5, in order to explain the positioning state between the silicon substrate 51 and the first mask 60, the positioning holes 24 of the silicon substrate 51, the openings 61 of the first mask 60, and the columnar protrusions 62 are provided. Although shown in the illustrated positions, these positions can be appropriately determined according to the shape of the silicon substrate 51.

  According to the above method, the through-hole 26 of the cavity substrate 20 and the opening 61 of the first mask substrate 60 are positioned by inserting the columnar protrusions 62 of the first mask substrate 60 into the positioning holes 24 of the cavity substrate 20. Since they can be adhered and laminated together, sealing work using the through groove 26 can be easily performed. Further, since the sealing material 25 can be deposited only in the through groove 26 through the opening 61 of the first mask substrate 60, the sealing material 25 can be efficiently disposed at a target location. Therefore, the sealing material 25 is not deposited on the terminal portion 14, a connection failure with the FPC or the like at the terminal portion 14 can be avoided, and the life can be extended. Furthermore, since the sealing material 25 can be deposited by sputtering, CVD, vapor deposition, or the like, the sealing process can be reliably performed on a plurality of wafers at once, and the sealing work efficiency is improved.

By the way, in the gap sealing step of FIG. 5H, one sheet of the first mask substrate 60 is used as the mask substrate for sealing. However, the second mask substrate is overlaid on the first mask substrate 60. Anyway. FIG. 6 is a reference diagram showing the mode, and shows a state where the second mask substrate 70 is positioned and closely stacked on the first mask substrate 60 and the sealing material 25 is deposited in the through groove 26. . In this case, an opening 61 and a plurality of columnar protrusions 62 are formed in the first mask substrate 60 at positions corresponding to the through grooves 26 and the positioning holes 24 of the cavity substrate 20, respectively, and the second mask substrate 70 is further formed. A plurality of positioning holes 63 for positioning are formed.
On the other hand, the second mask substrate 70 is formed with an opening 71 and a plurality of columnar protrusions 72 at positions corresponding to the opening 61 and the positioning hole 63 of the first mask substrate 60. The columnar protrusion 72 is shaped to fit into the positioning hole 63 of the first mask substrate 60.
When two mask substrates are used as shown in FIG. 6, in addition to the above-described effect, the sealing material 25 is not deposited on the first mask substrate that is in contact with the cavidie substrate 20, so that the sealing material is deposited. Warpage caused by can be avoided. For this reason, the sealing material 25 does not wrap around the gap between the cavidie substrate 20 and the first mask substrate 60, and more reliable sealing at a desired position is possible.

Embodiment 2
(Mask substrate)
FIG. 7 is a view for explaining the structure of the mask substrate used when the gap 40 described above is sealed through the through groove 26, and FIG. 7A shows the surface of the mask substrate in contact with the cavity substrate. 7B shows the side surface of the mask substrate, and FIG. 7C shows the upper surface of the silicon wafer on which the cavity substrate 20 on which the mask substrate is stacked is formed. The mask substrate 80 shown in FIG. 7 has a trapezoidal groove-shaped opening 81 (corresponding to reference numeral 61 in FIG. 5) and two columnar protrusions at positions corresponding to the through grooves 26 and the positioning holes 24 of the cavity substrate 20. A portion 82 (corresponding to reference numeral 62 in FIG. 5) is formed. Here, a recess 83 is provided in the center of the substrate. The recess 83 can be appropriately formed according to the usage mode, and is not necessarily required for the mask substrate for sealing the gap 40.
Here, the configuration for two rows of droplet discharge heads is described, but more columns are formed on the actual substrate (wafer), and the droplet discharge heads ( There are even more chips.

Next, a method for manufacturing a mask substrate will be described. 8 and 9 are process diagrams showing an example of a method for manufacturing the mask substrate 80. Hereinafter, description will be made according to (a) to (j) of these drawings.
(A) Both sides of a silicon single crystal substrate having a plane orientation (100) are polished to produce a silicon substrate (also denoted by reference numeral 80) having a thickness of about 700 μm.
(B) The silicon substrate 80 is thermally oxidized to form a silicon oxide film 90 on the surface of the substrate.
(C) The silicon oxide film 90 on one side of the silicon substrate 80 is subjected to patterning for forming the opening 81 by etching using a buffered hydrofluoric acid (BHF) solution.
(D) The silicon substrate 80 is immersed in a potassium hydroxide (KOH) solution, and an opening 81 is formed by etching.
(E) After removing the silicon oxide film 90 from both surfaces of the silicon substrate 80, the silicon substrate 80 is thermally oxidized again to form a silicon oxide film 90 on the surface of the substrate.

(F) Using the buffered hydrofluoric acid (BHF) solution, all of the silicon oxide film 90 in the recess 83 forming portion is etched with respect to the silicon oxide film 90 on the surface opposite to the opening 81 forming surface of the silicon substrate 80, In addition, the portions other than the columnar convex portion 82 forming portion are half-etched.
(G) The recess 83 is formed in the silicon substrate 80 by using dry etching, for example, ICP dry etching.
(H) The silicon oxide film 90 on the side where the concave portion 83 is formed on the silicon substrate 80 is etched using a buffered hydrofluoric acid (BHF) solution so that the silicon oxide film 90 remains only in the columnar convex portion 82 forming portion. Etch.
(I) Using dry etching, for example, ICP dry etching, etching is performed until the opening 81 previously formed penetrates the recess 83 forming side of the silicon substrate 80. At this time, only the columnar protrusion 82 forming portion remains without being etched, and the columnar protrusion 82 is formed. The shape of the columnar protrusion 82 is determined based on the shape of the masked material. In the case of the first mask substrate used in the method for manufacturing the droplet discharge head shown in FIGS. 4 and 5, for example, the diameter is 1 mm. The height may be 500 μm.
(J) Finally, the silicon oxide film 90 is removed from the silicon substrate 80 by etching using a dilute hydrofluoric acid (DHF) solution, whereby the mask substrate 80 is completed.

The mask substrate 80 made by the above method has a very high dimensional accuracy because the columnar convex portions 82 for positioning (alignment) are formed by photolithography and etching. As a result, the mask substrate 80 is used. The alignment accuracy is also very high.
In addition, since the columnar protrusions 82 are formed using photolithography and etching, a plurality of columnar protrusions 82 having a desired shape can be simultaneously formed on the mask substrate 80.
The mask substrate manufactured by the above method can be used not only as a mask for hermetic sealing, but also when directly forming a thin film pattern by other film forming methods (for example, vacuum deposition, ion plating, etc.). Can be used.

Embodiment 3
(Droplet discharge device)
FIG. 10 is a schematic configuration diagram of an ink jet printer which is a droplet discharge device incorporating the droplet discharge head manufactured in the first embodiment. In FIG. 10, a drum 101 that supports a print paper 110 that is a substrate to be printed and a droplet discharge head 102 that discharges ink to the print 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 for discharging to a substrate to be a color filter, a liquid containing a pigment for a color filter is included, and in an application to discharge an electroluminescent element to a substrate of a display panel (such as an OLED), a compound to be a light emitting element is included. In an application in which the liquid is wired on the substrate, for example, a liquid containing a conductive metal may be discharged from a droplet discharge head provided in each device. In addition, when the droplet discharge head is used as a dispenser and 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 acid, etc.) A liquid containing a probe such as a protein may be discharged. In addition, it can also be used when dye is discharged onto a cloth or the like.

FIG. 3 is an exploded perspective view of the droplet discharge head according to the first embodiment. Sectional drawing of a droplet discharge head. The top view showing the cavity board | substrate laminated | stacked on the electrode substrate. FIG. 5 is a process diagram illustrating a method for manufacturing the droplet discharge head according to the first embodiment. Process drawing following FIG. FIG. 6 is a reference diagram illustrating a state in which two mask substrates are used in FIG. Explanatory drawing explaining the structure of a mask substrate. Process drawing showing an example of the manufacturing method of a mask substrate. Process drawing following FIG. FIG. 5 is a configuration diagram of a droplet discharge device according to a third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electrode substrate, 11 Electrode formation groove, 12 Individual electrode, 13 Lead part, 14 Terminal part, 15 Liquid intake port, 20 Cavity board, 21 Discharge chamber, 22 Diaphragm, 23 Insulating film, 24 Positioning hole, 25 Sealing material , 26 Through groove, 27 Common electrode terminal, 28 Reservoir, 29 Orifice, 30 Nozzle substrate, 31 Nozzle hole, 32 Diaphragm, 40 Gap, 41 Oscillation drive circuit, 42 Wiring, 44 Electrode outlet, 50 Bonded substrate, 51 Silicon substrate , 52 Boron doped layer, 53 TEOS hard mask, 60 First mask substrate, 61 opening, 62 Columnar convex portion, 63 Positioning hole, 70 Second mask substrate, 71 opening, 72 Columnar convex portion, 80 Mask substrate, 81 Opening, 82 Columnar convex part.

Claims (6)

A joined body in which a first substrate having a fixed electrode and a second substrate having a movable electrode that opposes the fixed electrode through a gap and operates by an electrostatic force generated between the fixed electrode and the fixed electrode. Forming a through groove and a plurality of positioning holes for disposing a sealing material that shuts off the gap from outside air in the second substrate.
A first mask substrate made of a silicon substrate, in which an opening and a plurality of columnar protrusions are respectively formed at positions corresponding to the through groove and the positioning hole of the second substrate, is positioned on the second substrate. A step of inserting the columnar convex portion into the hole and closely laminating on the second substrate;
Depositing the sealing material in the through-groove through the opening of the first mask substrate to seal the gap. A joined body in which a first substrate having a fixed electrode and a second substrate having a movable electrode that opposes the fixed electrode through a gap and operates by an electrostatic force generated between the fixed electrode and the fixed electrode. Forming a through groove and a plurality of positioning holes for disposing a sealing material that shuts off the gap from outside air in the second substrate.
An opening and a plurality of columnar convex portions are formed at positions corresponding to the through groove and the positioning hole of the second substrate, and a plurality of positioning holes for positioning the second mask substrate are formed. A step of laminating the first mask substrate being adhered on the second substrate by inserting the columnar convex portions of the first mask substrate into the positioning holes of the second substrate;
A second mask substrate made of a silicon substrate and having openings and a plurality of columnar protrusions respectively formed at positions corresponding to the openings and positioning holes of the first mask substrate is used as positioning holes of the first mask substrate. Inserting a columnar convex portion of the second mask substrate into the first mask substrate and laminating the first mask substrate;
Depositing the sealing material in the through-groove through the openings of the first and second mask substrates and sealing the gap.   An electrostatic actuator is formed by applying the method for manufacturing an electrostatic actuator according to claim 1, and a flow path serving as a pressure chamber for storing and discharging droplets on the second substrate is formed. A method of manufacturing a droplet discharge head.   A method for manufacturing a droplet discharge device, comprising: manufacturing a droplet discharge head using the method for manufacturing a droplet discharge head according to claim 3; and incorporating the manufactured droplet discharge head. A mask substrate made of a silicon substrate and having an opening for depositing or depositing a member on a predetermined portion of the workpiece,
A mask substrate comprising a plurality of columnar convex portions for positioning with respect to the workpiece. A method of manufacturing a mask substrate for use in depositing or depositing a member on a predetermined portion of a workpiece,
The silicon substrate is subjected to anisotropic wet etching to form an opening for depositing or depositing a member on a predetermined portion of the workpiece, and the silicon substrate is subjected to dry etching or wet etching to the workpiece. A method for manufacturing a mask substrate, comprising: forming a plurality of columnar convex portions for positioning with respect to a substrate.

Images