KR20060043164A - Fluid actuating apparatus and method for manufacturing a fluid actuating apparatus, and electrostatically-actuated fluid discharge apparatus and process for producing an electrostatically-actuated fluid discharge apparatus - Google Patents

Abstract

An object of the present invention is to extend the diaphragm side electrode in the support so that the power consumption can be reduced and stress concentration between the diaphragm and the support can be prevented.

The diaphragm 17 which gives a pressure change to a fluid, the diaphragm side electrode 15 provided in the diaphragm 17 via the 3rd insulating film 16 by driving the diaphragm 17, and the diaphragm side electrode 15 To the substrate side electrode 12 provided between the diaphragm side electrode 15, the diaphragm side electrode 15 and the substrate side electrode 12, and the diaphragm via the space 31 with respect to the substrate side electrode 12. In the fluid vibration device 10 having the support 21 supporting the side electrode 15, the diaphragm side electrode 15 extends to reach a portion of the bottom of the support 21 through the support 21. will be.

Diaphragm, insulating film, substrate side electrode, diaphragm side electrode, strut

Description

FLUID ACTUATING APPARATUS AND METHOD FOR MANUFACTURING A FLUID ACTUATING APPARATUS, AND ELECTROSTATICALLY-ACTUATED FLUID DISCHARGE APPARATUS AND PROCESS FOR PRODUCING AN ELECTROSTATICALLY-ACTUATED FLUID DISCHARGE APPARATUS}

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a first embodiment of a fluid drive device of the present invention, (1) is a planar layout diagram, and (2) is a diagram showing a schematic configuration cross section along line AA in (1). (3) is a figure which shows schematic sectional drawing in the BB line in (1).

Fig. 2 is a manufacturing process diagram showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

3 is a manufacturing process diagram showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

4 is a manufacturing process drawing showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 5 is a manufacturing process diagram showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

6 is a manufacturing process drawing showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 7 is a manufacturing process chart showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

8 is a manufacturing process drawing showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

9 is a manufacturing process chart showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

10 is a manufacturing process chart showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

11 is a manufacturing process chart showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

12 is a manufacturing process chart showing the first embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 13 is a schematic configuration perspective view showing a first embodiment of an electrostatic drive fluid discharge device of the present invention.

Fig. 14 is a schematic sectional view showing the first embodiment of the electrostatic drive fluid discharge device of the present invention.

Fig. 15 is a diagram for explaining the operation of the electrostatic drive fluid discharge device.

Fig. 16 is a manufacturing process chart showing the first embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention.

Fig. 17 is a manufacturing process chart showing the first embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention.

Fig. 18 is a diagram showing the first embodiment of the electrostatic drive fluid discharge device of the present invention.

Fig. 19 is a plan view showing an example of an opening formed when removing a sacrificial layer pattern.

20 is a view showing a second embodiment of the fluid drive device of the present invention, in which FIG. 20 (1) is a planar layout diagram, and FIG. 20 (2) is a line AA in FIG. 20 (1). Fig. 20 (3) is a diagram showing a schematic configuration cross section taken along line BB in Fig. 20 (1).

Fig. 21 is a manufacturing process chart showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 22 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 23 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 24 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 25 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 26 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 27 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 28 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 29 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Fig. 30 is a manufacturing process chart showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

Figure 31 is a manufacturing process diagram showing the second embodiment of the manufacturing method of the fluid drive device of the present invention.

32 is a schematic configuration perspective view showing a second embodiment of an electrostatic drive fluid discharge device of the present invention.

Fig. 33 is a schematic sectional view showing the second embodiment of the electrostatic drive fluid discharge device of the present invention.

34 is a manufacturing process chart showing the second embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention.

Fig. 35 is a manufacturing process chart showing the second embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention.

<Explanation of symbols for the main parts of the drawings>

1: fluid driving device

11: substrate

12: substrate side electrode

13: first insulating film

14: second insulating film

15: diaphragm side electrode

16: third insulating film

17: diaphragm

18: fourth insulating film

21: prop

[Patent Document 1] Japanese Patent Application Laid-Open No. 10-86362

[Patent Document 2] Japanese Unexamined Patent Publication WO 99/34979

The present invention provides a fluid drive device and a fluid drive device which secures the repulsive force of the diaphragm while preventing stress from the deformation of the diaphragm from concentrating between the electrode and the support column when a voltage is applied to the electrode vibrating the diaphragm. A method of manufacturing a device, an electrostatic drive fluid discharge device using the fluid drive device, and a method of manufacturing the electrostatic drive fluid discharge device.

As a printer corresponding to the necessity of printing photographic image quality prints at high speed and with high precision, an ink jet printer head for discharging ink having a small volume of pl (picoliter) level has been widely used. In order to cope with the necessity of printing higher image quality at high speed and high precision, it is desired to dispose the nozzle without increasing the power consumption, without lowering the discharge performance, and at a high density.

Conventionally, the microchemical liquid driving method used for an inkjet printer head includes a resistance heating method and a diaphragm method for microfluidic fluid (micro-volume ink) held in an ink holding space (so-called cavity). The resistive heating method is a method of ejecting a fluid in a cavity from a nozzle by a gas (bubble) generated by resistive heating. The diaphragm method is a method of ejecting a fluid from a nozzle by pressure applying means (so-called diaphragm) using a piezo element or the like.

Since the resistance heating method can be manufactured by a semiconductor process, it is inexpensive and the resistance heating element can be manufactured minutely. Therefore, it is preferable to form a nozzle with high density, but since Joule heating by electric current is used, At the same time, it is difficult to increase the discharge frequency because power consumption is increased and cooling of the resistance heating element is required.

In addition, the diaphragm method using the piezo effect is classified into a laminated piezo type and a single plate piezo type, and the laminated piezo type uses a piezo actuator to the diaphragm, and then performs element separation by cutting, so that a semiconductor process cannot be used. The cost is high because the manufacturing process is complex. Moreover, since the drive distance is small, it is necessary to enlarge the drive area to the length of a millimeter (mm), and to secure a drive volume, and it is difficult to make high density. In addition, there is a problem that the design change is not easy.

In addition, a conventional electrostatic drive type inkjet head is formed by forming a diaphragm from a Si substrate thinly sliced by etching and bonding it to a substrate such as glass on which a lower electrode is formed. In this way, it is difficult to manage the film thickness of the diaphragm and its uniformity. In addition, since the diaphragm is etched from the Si substrate, most of the thickness of the Si substrate is removed, so that the productivity is deteriorated. It is difficult to increase density because it needs to be secured. Further, in order to bond the substrates together, the joining surface must be smoothed with high precision, a joining area for joining must be secured, and when joining, it is polymerized to require precision of a few 占 퐉 and cannot be densified. In addition, there was a problem that handling of a substrate having a thickness of about 0.1 to 0.2 mm was not easy.

Therefore, by forming the diaphragm in the semiconductor manufacturing process, it is easy to manage the thickness of the diaphragm, eliminate the need for joining the substrate, increase the density of the driving unit, obtain a high fluid driving force, and easily achieve high yield and design change. There is a need for a fluid drive device using an electrostatic method that aims at improving productivity.

Therefore, the single plate piezo type can use almost a semiconductor process, and the cost is also lower than that of the lamination type, and the power consumption can be reduced. However, warpage occurs due to the sintering of the piezoelectric element, and there is a problem in manufacturing a large head made into a nozzle. On the other hand, the diaphragm system using the electrostatic drive has a very low power consumption and high-speed drive as compared with the resistance heating and the piezo system (see Patent Documents 1 and 2, for example).

A diaphragm system using electrostatic driving is provided with a diaphragm for imparting a pressure change to a fluid, and by driving the diaphragm, a diaphragm side electrode is provided on the diaphragm via an insulating film, and the diaphragm side electrode faces the substrate through a space. A fluid drive device is provided by the present inventors in which a side electrode is provided, and a support column for supporting the diaphragm side electrode through the space with respect to the substrate side electrode.

In such an electrostatic drive fluid discharge device, the strength (repulsive force) and power consumption of the diaphragm are important specifications. For example, as a diaphragm system using electrostatic driving, a diaphragm for imparting a pressure change to a fluid is provided, and the diaphragm drives the diaphragm to provide a diaphragm side electrode through an insulating film, and faces the diaphragm side electrode. A fluid drive device in which a substrate side electrode is provided through a space and a support column for supporting a diaphragm side electrode through the space with respect to the substrate side electrode is provided by the present inventors. In this configuration, in which the diaphragm side electrodes formed separately, such as the fluid drive device, are formed in a rectangular shape with a size not to be caught by the support column, when a voltage is applied, stress is concentrated between the electrode and the support column due to deformation of the diaphragm. The problem is that the diaphragm is weak and the reaction force is insufficient.

The fluid drive device of the present invention includes a diaphragm for imparting a pressure change to a fluid, a diaphragm side electrode provided on the diaphragm by driving the diaphragm, a substrate side electrode provided to face the diaphragm side electrode, and the diaphragm side A fluid drive device having a space provided between an electrode and the substrate side electrode, and a support column for supporting the diaphragm side electrode through the space with respect to the substrate side electrode, wherein the diaphragm side electrode is disposed in the support column. The main feature is that it extends to reach a portion of the bottom of the support pillar.

The fluid drive device of the present invention includes a diaphragm for imparting a pressure change to a fluid, a diaphragm side electrode provided on the diaphragm by driving the diaphragm, a substrate side electrode provided to face the diaphragm side electrode, and the diaphragm side A fluid drive device having a space provided between an electrode and the substrate side electrode, and a support column for supporting the diaphragm side electrode through the space with respect to the substrate side electrode, wherein the diaphragm side electrode is disposed between the support pillars. The extension is the most important feature.

A method of manufacturing a fluid drive device of the present invention includes a step of forming a substrate side electrode on a substrate, a step of forming a first insulating film on the substrate side electrode, and a region other than a support pillar forming region on the first insulating film. Forming a sacrificial layer pattern for forming a space, forming a second insulating film covering the sacrificial layer pattern, upper side of the sacrificial layer pattern, sidewalls of the sacrificial layer pattern, and the support pillar forming region Forming a diaphragm side electrode on the bottom portion of the diaphragm through the second insulating film, forming a third insulating film covering the diaphragm side electrode, and a diaphragm for applying a pressure change to the fluid on the third insulating film. And forming a space in a region where the sacrificial layer pattern is removed by removing the sacrificial layer pattern, and at the same time, the support formed in the space side part. And a step of forming a supporting pillar in the supporting pillar forming region by the second insulating film, the diaphragm side electrode, the third insulating film, and the diaphragm in the pillar forming region.

A method of manufacturing a fluid drive device of the present invention includes a step of forming a substrate side electrode on a substrate, a step of forming a first insulating film on the substrate side electrode, and a region other than a support pillar forming region on the first insulating film. Forming a sacrificial layer pattern for forming a space; forming a second insulating film covering the sacrificial layer pattern; and forming a second insulating film on the sacrificial layer pattern including the support pillar forming region. Forming a diaphragm side electrode, forming a third insulating film covering said diaphragm side electrode, forming a diaphragm for applying a pressure change to a fluid on said third insulating film, and said sacrificial layer pattern To form a space in the region from which the sacrificial layer pattern is removed, and at the same time, the second insulating film and The main feature is that the step of forming a support pillar in the support pillar formation region by the third insulating film and the diaphragm is characterized.

The electrostatic drive fluid discharge device of the present invention includes a diaphragm for imparting a pressure change to a fluid, a diaphragm side electrode provided on the diaphragm by driving the diaphragm, a substrate side electrode provided to face the diaphragm side electrode, and A space provided between the diaphragm side electrode and the substrate side electrode, and a support column for supporting the diaphragm side electrode through the space with respect to the substrate side electrode, wherein the diaphragm side electrode passes through the support column. The main feature is that the pressure chamber is formed to extend to reach a portion of the bottom portion, and a pressure chamber having a supply portion and a discharge portion of the fluid is formed on the diaphragm.

The electrostatic drive fluid discharge device of the present invention includes a diaphragm for imparting a pressure change to a fluid, a diaphragm side electrode provided on the diaphragm through an insulating film to drive the diaphragm, and a substrate side electrode provided to face the diaphragm side electrode. And a space provided between the diaphragm side electrode and the substrate side electrode, and a support column supporting the diaphragm side electrode through the space with respect to the substrate side electrode, wherein the diaphragm side electrode extends between the support columns. And a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid is formed on the diaphragm.

The manufacturing method of the electrostatic drive fluid ejection apparatus of the present invention comprises the steps of forming a substrate side electrode on a substrate, forming a first insulating film on the substrate side electrode, and excluding a support pillar forming region on the first insulating film. Forming a sacrificial layer pattern for forming a space in the region, forming a second insulating film covering the sacrificial layer pattern, upper side of the sacrificial layer pattern, sidewalls of the sacrificial layer pattern, and the support pillar Forming a diaphragm side electrode on the portion of the bottom of the formation region through the second insulating film, forming a third insulating film covering the diaphragm side electrode, and applying a pressure change to the fluid on the third insulating film Forming a diaphragm, and forming a space in a region where the sacrificial layer pattern is removed by removing the sacrificial layer pattern, and formed in the space side part. Forming a support pillar in the support pillar formation region by the second insulating film, the diaphragm side electrode, the third insulating film, and the diaphragm in the support pillar formation region, and fluid on the vibration plate through the third insulating film. And a process for forming a pressure chamber having a supply portion and a discharge portion of a fluid.

The manufacturing method of the electrostatic drive fluid ejection apparatus of the present invention comprises the steps of forming a substrate side electrode on a substrate, forming a first insulating film on the substrate side electrode, and excluding a support pillar forming region on the first insulating film. Forming a sacrificial layer pattern for forming a space in the region, forming a second insulating film covering the sacrificial layer pattern, and forming the second insulating layer on the sacrificial layer pattern including the support pillar forming region; Forming a diaphragm side electrode through the insulating film, forming a third insulating film covering the diaphragm side electrode, forming a diaphragm for applying a pressure change to the fluid on the third insulating film, and sacrificial The layer pattern is removed to form a space in the region from which the sacrificial layer pattern is removed, and at the same time, the first pillar is formed in the support pillar forming region formed on the space side. Forming a support column in the support pillar forming region by the insulating film, the third insulating film and the diaphragm, and forming a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid on the diaphragm through the third insulating film; What has a process is the main characteristic.

After the diaphragm having sufficient repulsion force for driving the fluid, the use of the diaphragm side electrode has the purpose of reducing unnecessary power consumption and thus preventing stress concentration between the diaphragm side electrode and the support column. The structure which extends in a support column or the structure which extends between support pillars was implemented, without putting a load on the manufacturing method.

<First Embodiment>

A first embodiment of a fluid drive device of the present invention will be described with reference to FIG. Fig. 1 (1) shows a part of the planar layout diagram, (2) shows a schematic configuration cross section along the line AA in (1), and Fig. 1 (3) shows in Fig. 1 (1). A schematic configuration cross section in the BB line is shown. In addition, the scale of FIG. 1 (1) and FIG. 1 (2), (3) does not necessarily correspond. In addition, although the fluid drive apparatus is arrange | positioned in parallel, in the figure, the following description is given focusing on one fluid drive apparatus.

As shown in Fig. 1, a substrate-side electrode 12, which is formed of a conductive thin film and commonly used with other fluid driving devices (not shown), is formed on a substrate 11 having a surface formed by at least an insulating layer. have. The first insulating film 13 is formed on the substrate side electrode 12. The second insulating film 14 is formed so that the space 31 is formed on the first insulating film 13. Therefore, the space 31 is constituted by the first insulating film formed in a planar shape and the second insulating film 14 formed in three dimensions. The space 31 is a substantially rectangular parallelepiped space and is comb-shaped so as to enter the side of the space 31. Thus, the support pillar 21 including the second insulating film 14 is formed. The first insulating film 13 and the second insulating film 14 are insulating films for avoiding contact with the substrate side electrode 12 when the diaphragm side electrode described below is bent.

On the second insulating film 14, diaphragm side electrodes 15 which are driven independently of the space 31 through the second insulating film 14 are formed. The diaphragm side electrode 15 is formed in a rectangular shape (square or rectangle) in the plan view (when viewed from the top of the plan layout), and is formed in the shape of comb teeth along the side walls of the space in the support column formation region. It is formed along the side wall of the supporting pillar 21, which may be extended to a part of the bottom of the supporting pillar 21, but being formed on the entire bottom surface of the supporting pillar 21 causes an increase in capacitance. It is not preferable because the power consumption increases. Thus, the diaphragm-side electric power 15 is based on the rectangular electrode, and is extended in the support pillar formed like the comb-tooth shape along the side part of the space 31. As shown in FIG. In addition, since the leakage does not occur between the adjacent diaphragm side electrodes 15, the diaphragm side electrodes 15 are formed independently of each other.

The third insulating film 16 covering the diaphragm side electrode 15 is formed on the second insulating film 14. In addition, a pressure change is applied to the fluid on the third insulating film 16, and a plurality of diaphragms 17 having integrally driven diaphragm side electrodes 11 are arranged in parallel, and each diaphragm 17 is disposed. The support pillar 21 is formed on the board | substrate 11 and the real 1st insulating film 13 so that it may support by both girders. In addition, a fourth insulating film 18 is formed on the third insulating film 16 so as to cover the diaphragm 17. The third insulating film 16 is formed for the purpose of relieving the stress of the diaphragm 17 with respect to the diaphragm side electrode 15, and may be omitted when there is no need for stress relaxation. As described above, the second insulating film 14, the diaphragm side electrode 15, and the third insulating film 16 are formed in the support pillar forming region formed in the shape of the comb teeth so as to enter the space 31 side portion. ), The diaphragm 17 and the fourth insulating film 18.

In the illustrated example, the diaphragm 17 is formed in a single plate shape, and a plurality of support pillars 21 are formed at predetermined intervals (pitch between the support pillars) along the side portions of the diaphragm 17. Moreover, 2 micrometers or more and 10 micrometers or less are preferable for this predetermined space | interval (pitch between support pillars), and 5 micrometers is the most suitable. The adjacent diaphragm 17 is formed continuously through the support column 21, and the support column 21 also includes the diaphragm 17. As shown in FIG. Therefore, the space 31 between the diaphragm 17 and the board | substrate side electrode 12 communicates with the some diaphragm 17 in parallel. The whole space 31 which communicates between each diaphragm 17 is formed so that it may become a sealed space.

Between the support pillars 21 of the respective diaphragms 17, and in the present embodiment, between the support pillars 21 along the side of one diaphragm 17, the etching layer is etched and removed in the manufacturing process described later. Openings (not shown) for introducing gas or liquid are formed. After the sacrificial layer is etched away, the opening is closed by the member that is required.

As the substrate 11, for example, a semiconductor substrate such as silicon (Si) or gallium arsenide (GaAs) can be used, and an insulating film (not shown) is formed thereon. Accordingly, the substrate 11 may use an insulating substrate such as a glass substrate including a quartz substrate. In this case, it is not necessary to form the insulating film on the substrate surface. In this embodiment, a silicon substrate in which an insulating film made of a silicon oxide film or the like is formed on the surface of the substrate 11 is used.

The substrate-side electrode 12 includes a polycrystalline silicon film and a metal film doped with impurities (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium (Cr), and nickel (Ni)). ), Copper (Cu, etc.), an ITO (Indium Tin 0xide) film, or the like. Various film-forming methods, such as the film-forming method, vapor deposition method, vapor phase growth method, and sputtering method, can be used. Further, after forming the substrate-side electrode pattern by selective oxidation, implanting with B ⁺ , P ⁺ , B ⁺ , forming a channel stop layer on the p-Well, and implanting arsenic (As) n ⁺ diffusion layer electrode is formed. It is also possible. It is likewise possible to form a p ⁺ diffusion layer electrode on the n-Well. In this embodiment, an impurity doped polycrystalline silicon film was formed.

The diaphragm side electrode 15 can be formed with the material similar to the said board | substrate side electrode 12, and a film-forming method. That is, a polycrystalline silicon film and a metal film doped with impurities (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium (Cr), nickel (Ni), copper (Cu)) Etc.], and an indium tin oxide (ITO) film. Various film-forming methods, such as the film-forming method, vapor deposition method, vapor phase growth method, and sputtering method, can be used. In this embodiment, the diaphragm side electrode 15 is formed of a polycrystalline silicon film doped with impurities.

The diaphragm side electrode 15 is formed to be joined to the diaphragm 17 via the third insulating film 16 and to be inserted into the bent lower surface concave portion of the diaphragm 17, and also to the side wall side of the space 31. It is extended. The diaphragm 17 is formed of, for example, an insulating film, and in particular, it is preferable to form a silicon nitride film (SiN film) having a high repulsive force as the diaphragm due to tensile stress. In addition, a fourth insulating film 18 is formed on the upper surface of the diaphragm 17, and the fourth insulating film 18 is formed of, for example, a silicon oxide film. In addition, the 2nd insulating film 14 and the 3rd insulating film 16 can be formed with a silicon oxide film, for example. Accordingly, the diaphragm is substantially composed of the second insulating film 14, the diaphragm side electrode 15, the third insulating film 16, the diaphragm 17, and the fourth insulating film 18 in this embodiment.

The fluid drive device 1 having the above-described configuration vibrates the diaphragm 18 by applying a voltage between the substrate side electrode 12 and the diaphragm side electrode 15 to impart a pressure change to the fluid on the diaphragm 17. To move the fluid.

In the fluid drive device 1 of the present invention, since the diaphragm-side electrode 15 extends to reach a part of the bottom of the support column 21 through the support column 21, the entire bottom of the support column 21 is formed. The amount of electric charge stored in the bottom portion of the support column 21 which does not contribute to the deformation of the diaphragm 17 is smaller than the configuration in which the diaphragm side electrode 15 is formed so as to reach. In addition, since the strength of the diaphragm 17 is thicker than the structure in which the diaphragm side electrode 15 is formed so that it is not applied to the support column 21, only the film thickness of the diaphragm side electrode 15 becomes thick, and the support column 21 is firmly secured. There is an advantage. Moreover, the strain amount when 30 V is applied to the electrode of the fluid drive device 1 of the said structure, and the deformation amount when 61 kPa of distributed loads are applied were investigated. As a result, the charge density was 4.4 fF and the deformation amount was 13 nm. On the other hand, in the configuration in which the diaphragm-side electrode is provided outside the support column as in the conventional structure, the charge density is small at 1.7 fF, but the deformation amount is very large at 186 nm, and the diaphragm is excessively soft, resulting in insufficient repulsive force. In the configuration in which the diaphragm side electrode was extended to the entire bottom surface of the support column, the charge density was very large at 5.1 fF and the waste of power consumption was increased, but the deformation amount was small at 13 nm. Thus, the fluid drive device 1 of the present invention can be made into a small deformation amount without increasing the charge density much.

Second Embodiment

The first embodiment of the method of manufacturing the fluid drive device of the present invention will be described with reference to the manufacturing process diagrams of Figs. 2 to 12 mainly show a cross-sectional structure at positions similar to those of the A-A cross section and the B-B cross section shown in the planar layout diagram shown in FIG. 4 also shows a planar layout diagram of the sacrificial layer pattern.

As shown in Fig. 2, a substrate 11 having at least an insulating surface is prepared. For example, in this embodiment, a substrate in which an insulating film, for example, a silicon oxide film, is formed on a silicon substrate is used. A common substrate side electrode 12 is formed on the substrate 11. In this embodiment, the substrate-side electrode 12 is formed by depositing an amorphous silicon film by, for example, chemical vapor deposition (CVD), and then, for example, is doped with phosphorus (P) as an impurity. Thereafter, the doped impurities were activated by heat treatment and formed as electrodes having conductivity. As a result, the substrate-side electrode 12 of polycrystalline silicon is formed.

The substrate-side electrode 12 is formed of a polycrystalline silicon film doped with impurities, but for example, a metal film (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium ( Cr), nickel (Ni), copper (Cu), etc.], an ITO (Indium Tin 0xide) film, or the like. Various film-forming methods, such as the film-forming method, vapor deposition method, vapor phase growth method, and sputtering method, can be used. Further, after forming the substrate-side electrode pattern by selective oxidation, implanting with B ⁺ , P ⁺ , B ⁺ , forming a channel stop layer on the p-Well, and implanting arsenic (As) n ⁺ diffusion layer electrode is formed. It is also possible. It is likewise possible to form a p ⁺ diffusion layer electrode on the n-Well.

Next, as shown in FIG. 3, the first insulating film 13 is formed on the surface of the substrate-side electrode 12. As shown in FIG. The first insulating film 13 can be formed by, for example, a high temperature reduced pressure CVD method or a thermal oxidation method of about 1000 ° C. The first insulating film 13 is a protective film of the substrate-side electrode 11, a film resistant to the etching liquid or etching gas for etching the sacrificial layer, which will be described later, and the discharge prevention and the diaphragm when the diaphragm and the substrate-side electrode are approached. It is required to have a function such as short prevention when contacting the substrate-side electrode 11. As the first insulating film 13, for example, when using etching gas of sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), or difluoride xenon (XeF ₂ ), a silicon oxide (SiO ₂ ) film is used. For example, when using the etching liquid by hydrofluoric acid, it can be set as a silicon nitride (SiN) film. Next, the sacrificial layer 41 is formed on the entire surface of the first insulating film 13. As the sacrificial layer 41, in this embodiment, a polycrystalline silicon film is deposited from the CVD method.

Next, as shown in Fig. 4, by using a conventional lithography technique and an etching technique, a portion (not shown) to form a support pillar (so-called anchor) for supporting a diaphragm to be formed next is formed. In this case, the sacrificial layer 41 of the auxiliary support pillar) may be selectively etched away, and the opening 42 may be formed to form the sacrificial layer pattern 43. That is, one sacrificial layer pattern 43 is basically formed in a rectangular parallelepiped shape, and a region where the support pillar is formed is removed in a comb-tooth shape, and the removal portion becomes the opening portion 42 of the adjacent fluid driving device. The area communicating with the sacrificial layer pattern 43 for forming the space is formed in the shape of a comb teeth by the sacrificial layer 41. Moreover, since the etching of this sacrificial layer 41 has a part formed in comb-tooth shape, dry etching which can process with high precision is preferable.

Next, as shown in FIG. 5, a second insulating film 14 covering the surface of the sacrificial layer pattern 43 is formed on the first insulating film 13. Similar to the first insulating film 13, the second insulating film 14 is formed of a film resistant to the etching liquid or etching gas for etching the sacrificial layer 41. In this embodiment, since the sacrificial layer 41 by the polycrystalline silicon film is etched away using, for example, sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), and xenon difluoride (XeF ₂ ), As the second insulating film 14, a silicon oxide film (SiO ₂ film) is formed by thermal oxidation or CVD. In addition, the first and second insulating films 13 and 14 may protect the diaphragm-side electrode and short the discharge when the diaphragm and the diaphragm 12 come in contact with the substrate-side electrode 12 when the diaphragm and the substrate-side electrode 12 approach. It is required to have functions such as prevention. In addition, when the substrate-side electrode is not etched by the etchant of the sacrificial layer to etch the silicon oxide (SiO ₂ film) sacrificial layer by hydrofluoric acid, and when sufficient internal pressure can be ensured even by the second insulating film 14 only. It is possible to omit the first insulating film.

Next, as shown in FIG. 6, each of the independent diaphragm side electrodes 15 is formed on the second insulating film 14. In the present embodiment, the diaphragm side electrode 15 is formed by depositing an amorphous silicon film by chemical vapor deposition (CVD), for example, and then doping phosphorus (P) as an impurity, for example. Thereafter, the doped impurities were activated by heat treatment, and formed as electrodes having conductivity. As a result, the diaphragm side electrode 15 of polycrystalline silicon is formed. Since the diaphragm side electrode 15 is also formed in a support pillar, it forms in the upper part of the sacrificial layer pattern 43, the side wall side of the sacrificial layer pattern 43, and a part of the bottom part of the support pillar formation area | region through the 2nd insulating film 14. do. In the present embodiment, the diaphragm-side electrode 15 is extended to a part of the bottom of the support column, but the configuration may be extended to only the side wall.

The diaphragm side electrode 15 is formed of a polycrystalline silicon film doped with impurities, but for example, a metal film (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium ( Cr), nickel (Ni), copper (Cu), etc.], an ITO (Indium Tin 0xide) film, or the like. Various film-forming methods, such as the film-forming method, vapor deposition method, vapor phase growth method, and sputtering method, can be used.

Next, as shown in Fig. 7, a third insulating film 16 covering the diaphragm side electrode 15 is formed. The third insulating film 16 may be thermally oxidized, for example, to form a silicon oxide (SiO ₂ ) film on the surface of the diaphragm-side electrode 15, or may deposit silicon oxide by a chemical vapor deposition (CVD) method or the like. It may be formed by. The third insulating film 16 is formed for the purpose of relieving the stress of the diaphragm 17 to be formed next to the diaphragm side electrode 15, and may be omitted when stress relaxation is not necessary.

Next, as shown in FIG. 8, the diaphragm 17 which provides a pressure change with a fluid is formed in the whole surface on the 3rd insulating film 16. Next, as shown in FIG. The diaphragm 17 is formed of, for example, an insulating film, and in particular, it is preferable to form a silicon nitride film (SiN film) having a high repulsive force as a diaphragm due to tensile stress. As this film-forming method, a reduced pressure CVD method is mentioned, for example. As described above, the diaphragm 17 is formed of a silicon nitride film (SiN film), so that the diaphragm 17 has a tensile stress and a high repulsive force. Thus, the diaphragm 17 is preferable as a diaphragm.

Next, as shown in Fig. 9, a fourth insulating film 18 covering the diaphragm 17 is formed. This fourth insulating film 18 is formed of, for example, a silicon oxide film. As this insulating film 18, when using ink, a chemical | medical solution, and other liquid as a fluid, the hydrophilic insulating film 18 is formed in the liquid contact surface. When gas is used as the fluid, an insulating film 18 that is resistant to gas is formed. When using sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), or difluoride xenon (XeF ₂ ) gas in etching the sacrificial layer pattern 43, an oxide film having a resistance to the etching gas (eg, For example, the insulating film 18 is preferably formed of a silicon oxide film.

The diaphragm 17 by the silicon nitride film has a structure sandwiched by the third insulating film 16 and the fourth insulating film 18, but this structure is a laminate of a silicon nitride film having a tensile stress and a silicon oxide film having a compressive stress. When forming a structure, it is effective in preventing the diaphragm from bending. As a laminated structure of a silicon nitride film and a silicon oxide film, the diaphragm becomes largely concave due to the synergistic effect of tensile and compressive stresses, and the displacement of the diaphragm is insufficient. This warpage can be alleviated by covering both sides of the silicon nitride film with the silicon oxide film. Accordingly, the diaphragm is substantially composed of the second insulating film 14, the diaphragm side electrode 15, the third insulating film 16, the diaphragm 17, and the fourth insulating film 18 in this embodiment.

In addition, the second insulating film 14, the diaphragm side electrode 15, and the third insulating film 16 are formed in the support pillar forming region formed in the shape of the comb teeth so that the support pillar 21 enters the side of the sacrificial layer pattern 43. ), The diaphragm 17 and the fourth insulating film 18.

Next, as shown in FIG. 10, the sacrificial layer pattern penetrates through the fourth insulating film 18, the diaphragm 17, the third insulating film 16, the second insulating film 14, and the like in the vicinity of the support pillar 21. The opening 44 is formed so that the 43 is exposed. The openings 44 serve as exclusion holes when etching the sacrificial layer pattern 43 and can be formed by anisotropic dry etching such as reactive ion etching (RIE). Moreover, this opening part is enough to have a square of 2 micrometer square, and the smaller it is, the easier it is to block. In the case of dry etching, it was confirmed that sacrificial layer etching can be sufficiently performed even in a square of 0.5 mu m square. In addition, in this example, when using the thin diaphragm 17, in order to raise the repulsive force of the diaphragm 17 itself, the auxiliary support pillar (so-called post) (not shown) is provided directly under the center part of the diaphragm 17, and a support column ( 21) is also possible.

Next, as shown in FIG. 11, an etching solution or an etching gas is introduced through the opening 44, and in this embodiment, sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), and xenon difluoride (XeF _2). ) A gas is introduced to etch away the sacrificial layer pattern 43 (see FIG. 10 above), and a space 31 is formed between the diaphragm 17 and the substrate side electrode 12 having the diaphragm side electrode 15 integrally. Form. In this case, since the opening part 44 is formed in multiple numbers along the long side of the diaphragm 17, and etching advances to the direction along the short side of the diaphragm 17 through the opening part 44, etching in a short time is possible. Become. When silicon, such as polycrystalline silicon, is used as the sacrificial layer pattern 43, etching and removal can be performed by sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), and difluoride xenon (XeF ₂ ) gas. In the case where a silicon oxide film (SiO ₂ film) is used as the sacrificial layer pattern 43, it can be etched away with an etching solution of hydrofluoric acid. When the sacrificial layer pattern 43 is removed with an etching solution, a drying process is performed. As a result, the space 31 is formed in the region from which the sacrificial layer pattern 43 is removed, and the second insulating film 14, the diaphragm side electrode 15, and the first insulating film 14 are formed in the support pillar formation region formed at the side of the space 31. The support pillar 21 is formed in the support pillar formation region by the third insulating film 16, the diaphragm 17, and the fourth insulating film 18.

Next, as shown in FIG. 12, the opening part 44 is sealed by the sealing member 45. As shown in FIG. Although sealing is possible by the metal sputtering method, such as aluminum (Al), since the space 31 used as a vibration chamber becomes pressure-reduced, the diaphragm 17 becomes concave, and the support pillar 21 of the diaphragm 17 is carried out. Stress is always applied in the vicinity of (or auxiliary supporting column). Moreover, the movable range of the diaphragm 17 becomes narrow by becoming concave. In view of this point, for example, after forming a boron-phosphorus-silicate glass (BPSG) film, a method of filling the opening 44 by reflow treatment may be employed. When performing the reflow process, the pressure in the space 31 serving as the vibration chamber can be set to a desired value by performing in a nitrogen (N ₂ ) pressurized atmosphere. Moreover, the opening part 44 can also be blocked using the viscosity of the member which forms the pressure chamber mentioned later. In this way, the fluid drive device 1 is manufactured.

In the method of manufacturing the fluid drive device 1 of the present invention, the diaphragm side is formed on the upper side of the sacrificial layer pattern 43 and the side wall side of the sacrificial layer pattern 43 and a part of the bottom of the support pillar formation region through the second insulating film 14. Since the diaphragm side electrode 15 is extended so that the diaphragm-side electrode 15 may reach a part of the bottom part of the support column 21 through the inside of the support column 21, the support column 21 is provided. ) The amount of electric charge stored in the bottom of the support pillar 21 which does not contribute to the deformation of the diaphragm 17 is smaller than the configuration in which the diaphragm side electrode is formed so as to span the entire bottom part, and the amount of unnecessary power consumption is reduced. It can be formed as. In addition, since the strength of the diaphragm 17 is thicker only by the thickness of the diaphragm-side electrode 15 than the configuration in which the diaphragm-side electrode is formed so as not to be applied to the support column 21, the support column 21 is configured to be firm. There is an advantage that can be.

Third Embodiment

Next, a first embodiment of the electrostatic drive fluid discharge device of the present invention will be described with a schematic configuration perspective view of FIG. 13 and a schematic configuration sectional view of FIG. In this embodiment, an electrostatic head will be described as an example of an electrostatic drive fluid discharge device using the fluid drive device of the present invention.

First, as shown in FIG. 13, the electrostatic drive fluid discharge device (electrostatic head) 1 according to the present embodiment is a fluid drive formed by arranging a plurality of diaphragms 17 driven (vibrated) by an electrostatic force in high density in parallel. The apparatus 2 and the pressure chamber (so-called cavity) 22 and fluid 61 in which fluid 61 (represented by an arrow) are stored at respective positions on the diaphragms 17 are discharged to the outside. It consists of what is called a fluid supply part 55 provided with the discharge part 53 and the partition structure 54 with a nozzle (because liquid is used as a fluid) in this example. In addition, in the structure shown in the figure, the structure which the auxiliary support pillar (post) 23 was formed between the support pillars (anchor) 21 was shown.

14, the partition 52 of the fluid supply part 55 is provided in the position corresponding to the support column 21 which supports the vibration plate 17 with respect to the fluid drive device 1 of this invention. In order to be formed, the partition structure which has the pressure chamber 51 and the nozzle 53 is formed. That is, the fluid supply part 55 is arrange | positioned. The pressure chamber 51 communicates with a fluid supply path (not shown).

Next, the operation of the electrostatic driving fluid discharge device 2 will be described with reference to FIG. In addition, in the following description, the following structural component similar to the component demonstrated by FIG. 1, FIG. 13, FIG. 14 etc. is attached | subjected and demonstrated with the same code | symbol.

As shown in FIG. 15 (1), when a required voltage is applied between the substrate side electrode 12 and the diaphragm side electrode 15 in the fluid drive device 1, an electrostatic attraction occurs to generate a diaphragm side electrode. The diaphragm 17 which has the 15 was extended to the board | substrate side electrode 12 side. On the contrary, when the voltage application between the substrate side electrode 12 and the diaphragm side electrode 15 is opened, the diaphragm 17 is opened from the electrostatic force as shown in FIG. Vibration damped by Due to the volumetric fluctuation of the pressure chamber 51 by the vertical drive of the diaphragm 17, the fluid 61 in the pressure chamber 51 is discharged from the nozzle 53 to the outside, and the fluid ( 61) is supplied. When the diaphragm 17 is bent toward the substrate-side electrode 12, when the space 31 is a closed space, air between the diaphragm 17 and the substrate-side electrode 12 is compressed so that the bending of the diaphragm 17 is prevented. Although it intends to inhibit, since it is a support structure in the support column 21 (auxiliary support column 23), it is possible to escape the compressed air to the space 31 below the adjacent diaphragm 17, and the diaphragm 17 fully is carried out. Can bend.

Fourth Example

Next, a first embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention will be described with reference to the manufacturing process diagrams of FIGS. 16 and 17 show cross-sectional structures at positions similar to those of the A-A cross section and the B-B cross section shown in the planar layout diagram shown in FIG.

After the fluid drive device 1 is manufactured by the manufacturing method described with reference to Figs. 2 to 12, a partition film is formed on the fluid drive device 1 as shown in Fig. 16. This partition formation film can be formed with the photocurable resin material, for example, the epoxy resin material which has photosensitivity.

Then, a pressure chamber (so-called chamber) 51 for patterning the partition wall forming film using a lithography technique and an etching technique and storing the fluid and a supply flow path of the fluid communicating with the pressure chamber 51 (not shown) The partition wall 52 (52A) which comprises this is formed. That is, the pressure chamber 51 is formed on the diaphragm 17, and the partition 52 which comprises the pressure chamber 51 on the support column 21 of the adjacent fluid drive device 1 is formed, for example. Form.

Next, as shown in Fig. 17, a partition wall 52 (52B) having a discharge part (for example, a nozzle) 53 is closed so as to close the upper part of each pressure chamber 51, and an upper end part of the partition wall 52A. Bond or bond to the surface. The partition 52B is made of, for example, a sheet-like member (so-called nozzle sheet), and can be formed of, for example, a metal such as nickel and stainless steel or a required material such as a Si wafer. Through the above-described process, the electrostatic drive fluid discharge device 2 of the present invention is obtained.

In addition, by adjusting the viscosity of the photocurable resin, the opening 44 of the diaphragm 17 described in FIG. 12 is sealed without using the metal sputtering to form the sealing member 45. The member 45 can be formed and sealed.

According to the fluid drive device 1 according to the present embodiment, the diaphragm 17 is bent by the electrostatic force and the book power is the driving force, so that the microfluid can be controlled and supplied with high precision. When installing the auxiliary support column 23 directly under the middle of the diaphragm 17, even if the diaphragm 17 is made thin or the short side width of the diaphragm 17 is extended, the support column 21 of the diaphragm 17 is provided. Since the length between them becomes short in appearance, the repulsive force of the diaphragm 17 can be enlarged, and a required driving force can be obtained.

The diaphragm 17 is supported by a plurality of support pillars 21 integrated therein, and an opening 44 for introducing an etchant when etching the sacrificial layer pattern 43 in the vicinity of the support pillar 21 is provided. By setting it as one structure, in the formation of the space 31 between the diaphragm 17 and the board | substrate side electrode 12 of about 0.5 mm-3 mm long side and about 15 micrometers-100 micrometers short side, under the diaphragm 17 Since the space 31 formed by removing the sacrificial layer pattern 43 can be etched toward the short side, etching can be performed in a short time and the space 31 under each adjacent diaphragm 17 can be simultaneously formed. It also makes it possible to form with good precision. Therefore, it is possible to provide the fluid drive device 1 which secures the driving force for the fluid and enables high density.

By forming the lower substrate side electrode 12 as a common electrode and forming the upper diaphragm side electrode 15 as a plurality of independent electrodes, the lower surface of the diaphragm 17 can be formed flat. In the case where the lower substrate-side electrode 12 is used separately, since the step resulting from the thickness of the electrode becomes the step of the diaphragm 17, the tensile stress of the diaphragm 17 is relaxed to the step, and the tensile stress is It doesn't work. On the other hand, the diaphragm-side electrode 15 made of the silicon nitride (SiN) film and the diaphragm-side electrode 15 made of polycrystalline silicon (Si) is formed on the lower surface side formed by the stepped portion of the diaphragm 17 through the third insulating film 16. Since the diaphragm side electrode 15 is closely contacted and arrange | positioned, even if the diaphragm 17 has a step part, the tension of the diaphragm 17 is not absorbed by a step part.

Further, when the vertical relationship between the diaphragm 17 made of silicon nitride (SiN) film and the diaphragm side electrode 15 made of polycrystalline silicon (Si) is reversed, that is, the diaphragm 17 made of silicon nitride film is formed first. In the case where the diaphragm side electrode 15 of polycrystalline silicon is formed thereon, the diaphragm 17 can be flattened, but the voltage applied between the substrate side electrode 12 and the diaphragm side electrode 15 has a relative dielectric constant. Since it is also distributed to the high SiN film, the effective voltage acting on the space 31 on the lower surface of the diaphragm 17 and the upper surface of the substrate-side electrode 12 is lowered, so that the electrostatic attraction is lowered and the displacement of the diaphragm 17 is reduced. Since it also falls, it becomes disadvantageous when it aims at low power consumption driving.

In the case where the fluid 61 supplied to the pressure chamber 51 is a liquid, bubbles may be generated from the surface of the conductor or the surface of the conductor may corrode in the liquid 61, which is a conductor, where the liquid contactes, but in this embodiment, the diaphragm Since the diaphragm 17 exists on the side electrode 15, and the surface of the diaphragm 17 is coat | covered with the 4th insulating film 18, such a problem does not arise.

In the case where the fluid 61 is a liquid, the fourth insulating film 18 of the hydrophilic film is formed on the surface of the diaphragm 17 so that the liquid 61 can be smoothly introduced into the pressure chamber 51. . In addition, when the fluid 61 is gas, the diaphragm 17 does not invade with gas by forming the 4th insulating film 18 which is resistant to gas on the surface of the diaphragm 17. FIG.

According to the manufacturing method of the fluid drive apparatus 1 which concerns on a present Example, the sacrificial layer 41 and the diaphragm 17 are vapor-formed, and the following effects are exhibited. The uniformity of the space | interval between electrodes and the film thickness of the diaphragm 17 become high, and the fluctuation of the operating voltage between each diaphragm 17 becomes small. The flatness of the surface of the diaphragm 17 becomes high. Control of the electrode thickness and the film thickness of the diaphragm 17 becomes easy, and the diaphragm 17 of the desired film thickness can be made easily by film-forming time and temperature. Since it can be easily produced by a general semiconductor process, it is also excellent in mass production.

An opening 44 is formed in the vicinity of the support 21, and the sacrificial layer pattern 43 is etched away through the opening 44, so that the space between the diaphragm 17 and the substrate-side electrode 12 can be accurately formed. 31). Since the opening part 44 is formed in multiple numbers along the longitudinal direction of the diaphragm 17, the etching of the sacrificial layer pattern 43 is made in the short side direction of the diaphragm 17, and can shorten an etching time.

According to the electrostatic drive fluid discharge device 2 according to the present embodiment, by providing the fluid drive device 1 described above, the discharge portion 53 of the fluid 61 and the nozzle in this embodiment can be arranged at high density. At the same time, it is possible to precisely control and supply the small amount of fluid 61 with high driving force.

The electrostatic drive fluid discharge device 2 is provided with a plurality of high pressure chambers, medium pressure chambers, and low pressure chambers as pressure chambers 51, and connects each pressure chamber 51 to provide a check valve between the pressure chambers 51. It also arrange | positions so that fluid may flow by a pressure difference. An example thereof will be described with reference to FIG. In Fig. 18, a plan view is shown in Fig. 18 (1), a cross-sectional view is shown in Fig. 18 (2), and a cross-sectional view for explaining the operation is shown in Figs. 18 (3) and (4).

As shown in (1) and (2) of FIG. 18, the electrostatic drive fluid discharge device 2 is provided with the fluid drive device 1 of the present invention, and the pressure chamber is provided on the upper portion of the fluid drive device 1, respectively. 51 are provided, and they are provided in multiple numbers. The pressure chamber 51 is provided with, for example, a high pressure chamber, a medium pressure chamber, and a low pressure chamber, and each pressure chamber 51 is connected by flow paths 71 and 72, and between each pressure chamber 51. Non-return valves 75 and 76 are arranged. These non-return valves 75 and 76 open and close with the downstream side as a support point. Arrows in the figure indicate the direction in which the fluid flows.

The electrostatic drive fluid discharge device 2, in the fluid drive device 1, as shown in Fig. 18 (3), applies a required voltage between the substrate side electrode 12 and the diaphragm side electrode 15. When applied, an electrostatic attraction occurs and the diaphragm 17 having the diaphragm side electrode 15 floats to the side of the substrate side electrode 12. On the contrary, when the application of voltage between the substrate side electrode 12 and the diaphragm side electrode 15 is opened, the diaphragm 17 is opened from the electrostatic force as shown in Fig. 18 (4), and its restoring force Vibrates by damping. The pressure chamber 51 causes a volume fluctuation by the vertical drive of the diaphragm 17. As shown in Fig. 18 (3), when the volume of the pressure chamber 51 is enlarged, the pressure chamber 51 is depressurized, so that it is in a negative pressure state on the downstream side, and the backflow prevention valve 75 is in an open state. . On the other hand, since the negative pressure is also applied to the upstream side, the non-return valve 76 is closed. As shown in Fig. 18 (4), when the volume of the pressure chamber 51 is reduced, the pressure chamber 51 is pressurized, so that the pressure chamber 51 is in a high pressure state on the downstream side, and the backflow prevention valve 75 is closed. On the other hand, since the pressure is also upstream, the backflow prevention valve 76 is opened. In this way, the fluid 61 can be supplied in the direction of the arrow by causing a pressure difference before and after the pressure chamber 51.

Although the electrostatic drive fluid discharge device 12 is not shown, when using gas as a fluid, it can be comprised so that a valve may be provided in the discharge port to the exterior of the pressure chamber 51 basically.

In the present invention, a partition structure having a fluid drive device 1 including a diaphragm 17, a pressure chamber 51 of a fluid, and a discharge part (for example, a nozzle) 53 by surface micromachining without bonding. It becomes possible to manufacture the electrostatic drive fluid discharge device 12 consisting of 54. Since a standard semiconductor process can be used, including the step of etching away the sacrificial layer pattern 43 from the opening 44 provided in the vicinity of the support 21, the fluid drive device 1 and the electrostatic drive fluid discharge device ( Cost reduction of 2) can be aimed at.

Further, the electrostatic discharge is formed by joining the partition structure 54 having the discharge part (for example, nozzle) 53, the pressure chamber 51, and the fluid supply flow path (not shown) formed separately on the fluid drive device 1. The drive fluid discharge device 2 may be manufactured. Moreover, as the opening part 44, as shown in FIG. 19, you may form multiple in the vicinity of one support | pillar 21, for example. In the drawing, two pieces are formed on both sides in the longitudinal direction of the strut 21 and one piece in the short direction, but the number can be appropriately selected. Moreover, the formation position can also be selected suitably. In addition, the strut 21 and the auxiliary strut 23 are formed of a material constituting the diaphragm 17, the diaphragm side electrode 15, the second insulating film 14, the third insulating film 16, and the fourth insulating film 18. It can be formed as a part.

(Example 5)

Next, a second embodiment of the fluid drive device of the present invention will be described with reference to FIG. The fluid drive device of the second embodiment has only the configuration of the diaphragm side electrode in the fluid drive device described in the first embodiment. Therefore, in the following description, the same code | symbol is attached | subjected to the component which becomes the same as 1st Example. FIG. 20 (1) shows a part of the planar layout diagram, FIG. 20 (2) shows a schematic configuration cross section along the line AA in FIG. 20 (1), and FIG. 20 (3). Fig. 20 shows a schematic cross section of the BB line in Fig. 20 (1). In addition, the scale of FIG. 20 (1) and FIG. 20 (2), (3) does not necessarily correspond. In addition, although the fluid drive apparatus is arrange | positioned in parallel, the following description is given focusing on one fluid drive apparatus in drawing.

As shown in Fig. 20, a substrate-side electrode 12 which is formed of a conductor thin film and which is commonly used with other fluid driving devices (not shown) is formed on a substrate 11 whose surface is formed by at least an insulating layer. have. The first insulating film 13 is formed on the substrate side electrode 12. The second insulating film 14 is formed on the first insulating film 13 so that the space 31 is formed. Therefore, the space 31 is composed of the first insulating film formed in a planar shape and the second insulating film 14 formed in three dimensions. The space 31 is a substantially rectangular parallelepiped space, and is combed so as to be drawn into the side of the space 31. The strut 21 including the second insulating film 14 is formed. The first insulating film 13 and the second insulating film 14 are insulating films for avoiding contact with the substrate side electrode 12 when the diaphragm side electrode described later is bent.

On the second insulating film 14, diaphragm side electrodes 15 which are driven independently of the space 31 via the second insulating film 14 are formed. The diaphragm-side electrode 15 is formed into a rectangle (square or rectangle) when viewed from a plane (when the planar layout is also viewed from above), and is formed to extend between the strut formation regions. Therefore, the diaphragm-side electrode 15 is formed in the comb-tooth shape between the strut formation areas. Thus, the diaphragm-side electric power 15 is based on a rectangular electrode, and is extended and extended between strut formation areas like a comb tooth. In addition, the diaphragm-side electrode 15 is formed independently of each other so that a ring does not arise between adjacent diaphragm-side electrodes 15.

The third insulating film 16 covering the diaphragm side electrode 15 is formed on the second insulating film 14. In addition, a pressure change is applied to the fluid on the third insulating film 16, and a plurality of diaphragms 17 having integrally driven diaphragm side electrodes 11 are arranged in parallel, and each diaphragm 17 is disposed. The support 21 is formed on the substrate 11 and the real first insulating film 13 so as to be supported by both beams. Further, a fourth insulating film 18 is formed on the third insulating film 16 so as to cover the diaphragm 17. The third insulating film 16 is formed for the purpose of relieving the stress of the diaphragm 17 with respect to the diaphragm side electrode 15, and may be omitted if there is no need for stress relaxation. As described above, the post 21 is formed in the post forming region formed in the shape of the comb to draw into the space 31 side, and the second insulating film 14, the diaphragm side electrode 15, the third insulating film 16 and the diaphragm are formed. It is formed of the 17 and the fourth insulating film 18.

In the example shown, the said diaphragm 17 is formed in the unitary form, and the several pillar 21 is provided in predetermined intervals (pitch | interval pitch) along the side part of the diaphragm 17, respectively. Moreover, 2 micrometers or more and 10 micrometers or less are preferable for this predetermined space | interval (period pitch), and 5 micrometers is suitable. Adjacent diaphragm 17 is continuously formed via strut 21, and strut 21 is also formed including diaphragm 17. As shown in FIG. Therefore, the space 31 between the diaphragm 17 and the board | substrate side electrode 12 communicates with the some diaphragm 17 in parallel. The whole space 31 which communicates between each diaphragm 17 is formed so that it may become a sealed space.

Near the support 21 of each of the diaphragms 17, in this embodiment, between each support 21 along the side of one diaphragm 17, a substrate for etching and removing the sacrificial layer in a manufacturing process described later or An opening (not shown) for introducing a liquid is formed. After the sacrificial layer is etched away, the opening is closed by the required member.

For example, a semiconductor substrate such as silicon (Si) or gallium arsenide (GaAs) may be used as the substrate 11, and an insulating film (not shown) is formed thereon. Accordingly, the substrate 11 may use an insulating substrate such as a glass substrate including a quartz substrate. In this case, it is not necessary to form an insulating film on the substrate surface. In this embodiment, a silicon substrate in which an insulating film made of a silicon oxide film or the like is formed on the surface of the substrate 11 is used.

The substrate-side electrode 12 includes a polycrystalline silicon film and a metal film doped with impurities (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium (Cr), and nickel (Ni)). ), Copper (Cu, etc.), an indium tin oxide (ITO) film, or the like. Various film forming methods such as the film forming method, vapor deposition method, vapor phase growth method, and sputtering method can be used. Further, after forming the substrate-side electrode pattern by selective oxidation, implanting with B ⁺ , P ⁺ , B ⁺ , forming a channel stop layer on the p-Well, and implanting arsenic (As) to n ⁺ diffusion layer It is also possible to form an electrode. Similarly, it is possible to form a p ⁺ diffusion layer electrode on the n-Well. In this embodiment, an impurity doped polycrystalline silicon film was formed.

The diaphragm side electrode 15 may be formed using the same material as the substrate side electrode 12 or a film forming method. That is, a polycrystalline silicon film and a metal film doped with impurities (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium (Cr), nickel (Ni), copper (Cu)) Etc.], and an indium tin oxide (ITO) film. Various film forming methods such as the film forming method, vapor deposition method, vapor phase growth method, and sputtering method can be used. In this embodiment, the diaphragm side electrode 15 is formed of a polycrystalline silicon film doped with impurities.

The diaphragm side electrode 15 is joined to the diaphragm 17 via the third insulating film 16, and is formed to be inserted into the bent lower surface recess of the diaphragm 17, and also extends to the side wall side of the space 31. Formed. The diaphragm 17 is formed of, for example, an insulating film, and in particular, it is preferable to form a silicon nitride film (SiN film) having a high repulsive force as the diaphragm due to tensile stress. Further, a fourth insulating film 18 is formed on the upper surface of the diaphragm 17, and the fourth insulating film 18 is formed of, for example, a silicon oxide film. In addition, the 2nd insulating film 14 and the 3rd insulating film 16 can be formed with a silicon oxide film, for example. Therefore, in the present embodiment, the diaphragm is substantially composed of the second insulating film 14, the diaphragm side electrode 15, the third insulating film 16, the diaphragm 17, and the fourth insulating film 18.

The fluid drive device 3 of the above configuration vibrates the diaphragm 18 by applying a voltage between the substrate side electrode 12 and the diaphragm side electrode 15 to impart a pressure change to the fluid on the diaphragm 17. To move the fluid.

The fluid drive device 3 of the present invention is formed so that the diaphragm side electrode 15 extends to reach a part of the bottom of the support 21 through the middle of the support 21, so as to reach the entire bottom of the support 21. The amount of charge that accumulates at the bottom of the support 21 that does not contribute to the deformation of the diaphragm 17 is smaller than the configuration in which the diaphragm side electrode 15 is formed, and the amount of unnecessary power consumption is reduced. In addition, there is an advantage that the strength of the diaphragm 17 is stronger than the configuration in which the diaphragm side electrode is formed so as not to be caught by the strut 21. Moreover, the strain amount when 30 V was applied to the electrode of the fluid drive device 3 of the said structure, and the deformation amount when 61 kPa of distributed loads were applied were investigated. As a result, the charge density was 2.7 fF and the amount of deformation was 88 nm. On the other hand, as in the conventional structure, the diaphragm side electrode is not extended in the support, and the charge density is small at 1.7 fF, but the deformation amount is very large at 186 nm, and when the vibrating plate vibrates, the vibrating plate contacts the lower surface and smoothly vibrates. It did not happen. Thus, the fluid drive device 3 of the present invention can be made into a small deformation amount without increasing the charge density much.

(Example 6)

A second embodiment of the method of manufacturing the fluid drive device of the present invention will be described with reference to the manufacturing process diagrams of Figs. 21 to 31 show a cross-sectional structure mainly at the same positions as the A-A line cross section and the B-B line cross section shown in the planar layout diagram shown in FIG. 20 (1). 23 also shows a plan layout of the sacrificial layer pattern.

As shown in Fig. 21, a substrate 11 whose surface is at least insulating is prepared. For example, in this embodiment, a substrate in which an insulating film, for example, a silicon oxide film, is formed on a silicon substrate is used. A common substrate side electrode 12 is formed on the substrate 11. In this embodiment, the substrate-side electrode 12 is formed by depositing an amorphous silicon film by, for example, chemical vapor deposition CVD, and then, for example, is doped with phosphorus (P) as an impurity. Thereafter, the doped impurity was activated to form a conductive electrode. As a result, the substrate-side electrode 12 of polycrystalline silicon is formed.

The substrate-side electrode 12 is formed of a polycrystalline silicon film doped with impurities, but for example, a metal film (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium ( Cr), nickel (Ni), copper (Cu), etc.], an indium tin oxide (ITO) film, or the like. Various film forming methods such as the film forming method, vapor deposition method, vapor phase growth method, and sputtering method can be used. Further, after forming the substrate-side electrode pattern by selective oxidation, implanting with B ⁺ , P ⁺ , B ⁺ , forming a channel stop layer on the p-Well, and implanting arsenic (As) to n ⁺ diffusion layer It is also possible to form an electrode. Similarly, it is possible to form a p ⁺ diffusion layer electrode on the n-Well.

Next, as shown in FIG. 22, a first insulating film 13 is formed on the surface of the substrate-side electrode 12. As shown in FIG. The first insulating film 13 can be formed by, for example, a high temperature reduced pressure CVD method or a thermal oxidation method at about 1000 ° C. The first insulating film 13 is a protective film of the substrate-side electrode 11, a film resistant to the etching liquid or etching gas for etching the sacrificial layer, which will be described later, and the discharge prevention when the diaphragm and the substrate-side electrode approach, and the diaphragm. It is required to have a function such as short prevention when contacting the substrate side electrode 11. As the first insulating film 13, for example, when using etching gas of sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), or xenon difluoride (XeF ₂ ), a silicon oxide (SiO ₂ ) film is used. For example, when using the etching liquid by hydrofluoric acid, it can be set as a silicon nitride (SiN) film. Next, the sacrificial layer 41 is formed on the entire surface of the first insulating film 13. As the sacrificial layer 41, in this embodiment, a polycrystalline silicon film is deposited from the CVD method.

Next, as shown in Fig. 23, a part (so-called anchor) which should form a support (so-called anchor) for supporting a diaphragm to be formed later by using a conventional lithography technique and an etching technique is formed. The sacrificial layer 41 of the auxiliary strut) is selectively etched away to form the opening 42, and the sacrificial layer pattern 43 is formed. That is, one sacrificial layer pattern 43 is basically formed in a rectangular parallelepiped shape, the region where the post is formed is removed in the shape of a comb tooth, and the removal portion thereof becomes the opening portion 42, and the adjacent fluid driving device The area communicating with the sacrificial layer pattern 43 for forming the space of the sacrificial layer 41 is formed in the shape of a comb teeth. In addition, since the etching of this sacrificial layer 41 has a part formed in the shape of a comb tooth, dry etching which can process with high precision is preferable.

Next, as shown in FIG. 24, a second insulating film 14 covering the surface of the sacrificial layer pattern 43 is formed on the third insulating film 13. Similar to the first insulating film 13, the second insulating film 14 is formed of a film resistant to the etching liquid or etching gas for etching the sacrificial layer 41. In this embodiment, the sacrificial layer 41 made of a polycrystalline silicon film is etched away using, for example, sulfur hexafluoride (SF ₆ ) or carbon tetrafluoride (CF ₄ ) or xenon difluoride (XeF ₂ ). 2 The insulating film 14 is formed of a silicon oxide film (SiO ₂ film) by, for example, thermal oxidation or CVD so that the insulating film 14 becomes an etching stopper. In addition, the second insulating film 14 has functions such as protection of the diaphragm side electrode, prevention of discharge when the diaphragm and the substrate side electrode 12 approach, and short circuit prevention when the diaphragm contacts the substrate side electrode 12. To be required. In addition, when the substrate-side electrode is not etched by the etchant of the sacrificial layer to etch the silicon oxide (SiO ₂ film) sacrificial layer by hydrofluoric acid, and when the second insulating film 14 alone can ensure sufficient breakdown voltage. It is possible to omit the first insulating film.

Next, as shown in FIG. 25, respective independent diaphragm side electrodes 15 are formed on the second insulating film 14. In the present embodiment, the diaphragm side electrode 15 is formed by depositing an amorphous silicon film by, for example, chemical vapor deposition (CVD), and then, for example, is doped with phosphorus (P) as an impurity. Thereafter, the doped impurity was activated to form a conductive electrode. As a result, the diaphragm side electrode 15 of polycrystalline silicon is formed. The diaphragm-side electrode 15 is formed on the sacrificial layer pattern 43 including between the strut formation regions via the second insulating film 14.

The diaphragm side electrode 15 is formed of a polycrystalline silicon film doped with impurities, but for example, a metal film (for example, platinum (Pt), titanium (Ti), aluminum (Al), gold (Au), chromium ( Cr), nickel (Ni), copper (Cu), etc.], an indium tin oxide (ITO) film, or the like. Various film forming methods such as the film forming method, vapor deposition method, vapor phase growth method, and sputtering method can be used.

Next, as shown in Fig. 26, a third insulating film 16 covering the diaphragm side electrode 15 is formed. For example, the third insulating film 16 may be thermally oxidized on the surface of the diaphragm side electrode 15 to be formed of a silicon oxide (SiO ₂ ) film, or silicon oxide may be deposited by a chemical vapor deposition (CVD) method or the like. It may be formed by. The third insulating film 16 is formed to relieve the stress of the diaphragm 17 with respect to the diaphragm side electrode 15, and may be omitted when there is no need for stress relaxation.

Next, as shown in FIG. 27, a diaphragm 17 is formed on the entire surface of the third insulating film 16 to impart a pressure change to the fluid. The diaphragm 17 is formed of, for example, an insulating film, and in particular, it is preferable to form a silicon nitride film (SiN film) having a high repulsive force as a diaphragm due to tensile stress. As this film-forming method, a reduced pressure CVD method is mentioned, for example. By forming the diaphragm 17 as the silicon nitride film (SiN film) as mentioned above, since the diaphragm 17 has tension stress and high repulsive force, it is suitable as a diaphragm.

Next, as shown in FIG. 28, a fourth insulating film 18 covering the diaphragm 17 is formed. This fourth insulating film 18 is formed of, for example, a silicon oxide film. As this insulating film 18, when using ink, a chemical | medical solution, and other liquid as a fluid, the hydrophilic insulating film 18 is formed in the liquid contact surface. When gas is used as the fluid, an insulating film 18 that is resistant to gas is formed. When using sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), or xenon difluoride (XeF ₂ ) gas in etching the sacrificial layer pattern 43, an oxide film that is resistant to the etching gas (for example, It is preferable to form the insulating film 18 with a silicon oxide film.

Although the diaphragm 17 by the silicon nitride film is comprised by the 3rd insulating film 16 and the 4th insulating film 18, this structure is a laminated structure of the silicon nitride film which has a tensile stress, and the silicon oxide film which has a compressive stress. In the case of forming a, it is effective in preventing the vibration of the diaphragm. In the laminated structure of the silicon nitride film and the silicon oxide film, the diaphragm becomes largely concave due to the synergistic effect of the tensile and compressive stresses, and the displacement of the diaphragm is insufficient. This warpage can be alleviated by covering both sides of the silicon nitride film with a silicon oxide film. Therefore, in the present embodiment, the diaphragm is substantially composed of the second insulating film 14, the diaphragm side electrode 15, the third insulating film 16, the diaphragm 17, and the fourth insulating film 18.

In addition, the support 21 is formed in the support formation region formed in the shape of the comb so as to be drawn into the side of the sacrificial layer pattern 43. The second insulating film 14, the third insulating film 16, the diaphragm 17, and the fourth insulating film ( 18).

Next, as shown in Fig. 29, the sacrificial layer pattern is formed through the fourth insulating film 18, the diaphragm 17, the third insulating film 16, the second insulating film 14, and the like in the vicinity of the support 21. Opening 44 is formed to expose 43. The openings 44 serve as missing holes when etching the sacrificial layer pattern 43 and can be formed by anisotropic dry etching such as reactive ion etching (RIE). Moreover, this opening part is enough in the square below 2 micrometers angle, and it is easy to occlude as it is small. In the case of dry etching, it was confirmed that sacrificial layer etching can be sufficiently performed even in a square of 0.5 mu m angle. In addition, in the present example, when the thin diaphragm 17 is used, in order to increase the repulsive force of the diaphragm 17 itself, an auxiliary strut (so-called post) (not shown) is provided directly under the center of the diaphragm 17 and the strut 21. It is also possible to form simultaneously.

Next, as shown in FIG. 30, etching liquid or etching gas is introduced through the opening 44, and in this embodiment, sulfur hexafluoride (SF ₆ ), carbon tetrafluorocarbon (CF ₄ ), and xenon difluoride (XeF _2). ) A gas is introduced to etch away the sacrificial layer pattern 43 (see FIG. 29 above), and a space 31 is formed between the diaphragm 17 and the substrate side electrode 12 having the diaphragm side electrode 15 integrally. Form. In this case, since the opening part 44 is formed in multiple numbers along the long side of the diaphragm 17, and etching progresses along the short side of the diaphragm 17 through the opening part 44, etching in a short time becomes possible. . When silicon such as polycrystalline silicon is used as the sacrificial layer pattern 43, etching and removal can be performed by sulfur hexafluoride (SF ₆ ), carbon tetrafluoride (CF ₄ ), and xenon difluoride (XeF ₂ ) gases. In the case where a silicon oxide film (SiO ₂ film) is used as the sacrificial layer pattern 43, it can be etched away with an etching solution of hydrofluoric acid. When the sacrificial layer pattern 43 is removed with an etching solution, a drying process is performed. As a result, the space 31 is formed in the region from which the sacrificial layer pattern 43 is removed, and the second insulating film 14, the third insulating film 16, and the diaphragm ( The support 21 is formed in the support formation region by the 17 and the fourth insulating film 18.

Next, as shown in FIG. 31, the opening part 44 is sealed by the sealing member 45. As shown in FIG. Although sealing is possible by the metal sputtering method, such as aluminum (Al), since the space 31 which becomes a vibration chamber becomes pressure reduction, the diaphragm 17 becomes concave, and the support | pillar 21 of the diaphragm 17 ( Or stress is always applied in the vicinity of the auxiliary support). Moreover, the movable range of the diaphragm 17 becomes narrow by becoming concave. In view of this point, for example, after forming a boron-phosphorus-silicate glass (BPSG) film, a method of filling the opening 44 by reflow treatment may be employed. At the time of reflow processing, it is possible to set the pressure of the space 31 to be a vibration chamber to a desired value by performing in a nitrogen (N ₂ ) pressurized atmosphere. Moreover, the opening part 44 can also be closed using the viscosity of the member which forms the pressure chamber mentioned later. In this way, the fluid drive device 3 is manufactured.

Since the manufacturing method of the fluid drive device 3 of the present invention includes a step of forming the diaphragm side electrode 15 on the sacrificial layer pattern 43 including between the strut formation regions via the second insulating film 14. The amount of charge that accumulates in the bottom of the support 21 that does not contribute to the deformation of the diaphragm 17 is smaller than the configuration in which the diaphragm-side electrode is formed so as to cover the entire bottom of the support 21. It can be formed with a structure reduced. In addition, there is an advantage that the strength of the diaphragm 17 is stronger than the configuration in which the diaphragm side electrode is formed so as not to be caught by the strut 21.

(Example 7)

Next, a second embodiment of the electrostatic drive fluid discharge device of the present invention will be described with a schematic configuration perspective view of FIG. 32 and a schematic configuration sectional view of FIG. In this embodiment, as an example, an electrostatic head will be described as an example of an electrostatic drive fluid discharge device using the fluid drive device of the present invention.

First, as shown in FIG. 32, the electrostatic drive fluid discharge device (electrostatic head) 4 according to the present embodiment is a fluid drive formed by arranging a plurality of diaphragms 17 driven (vibrated) by an electrostatic force in high density in parallel. The discharge which discharges the pressure chamber (so-called cavity) 22 and the fluid 61 which the fluid 61 (represented by the arrow) settles in the apparatus 3 and corresponding position on each diaphragm 17, respectively, to the outside. The part 53, in this example, consists of a so-called fluid supply part 55 having a partition structure 54 having a nozzle (because liquid is used as the fluid). In addition, in the structure shown in the figure, the structure in which the auxiliary support (post) 23 was formed between the support (anchor) 21 was shown.

In addition, as shown in FIG. 33, the pressure so that the partition 52 of the fluid supply part 55 is formed in the position corresponding to the support | pillar 21 which supports the diaphragm 17 with respect to the fluid drive device 3 of this invention is shown. A partition structure having a chamber 51 and a nozzle 53 is formed. That is, the fluid supply part 55 is arrange | positioned. The pressure chamber 51 communicates with a fluid supply path (not shown).

The operation of the electrostatic drive fluid discharge device 4 becomes the same as that of the electrostatic drive fluid discharge device 2.

(Example 8)

Next, a second embodiment of the manufacturing method of the electrostatic drive fluid discharge device of the present invention will be described with reference to the manufacturing process diagrams of FIGS. 34 and 35 show cross-sectional structures at the same positions as the A-A line cross section and the B-B line cross section shown in the planar layout diagram shown in FIG. 20 (1).

After the fluid drive device 3 is manufactured by the manufacturing method described with reference to Figs. 21 to 31, a partition film is formed on the fluid drive device 3 as shown in Fig. 35. Figs. This partition formation film can be formed with a photocurable resin material, for example, the epoxy resin material which has photosensitivity. After that, the barrier rib forming pattern is patterned using lithography and etching techniques, and a pressure chamber (so-called chamber) 51 for collecting the fluid and a supply flow path (not shown) for communicating with the pressure chamber 51 are provided. The partition walls 52 and 52A which comprise are formed. That is, the partition wall 52 for forming the pressure chamber 51 on the diaphragm 17, and forming the pressure chamber 51 on the support | pillar 21 of the adjacent fluid drive device 1, for example is provided. Form.

Next, as shown in Fig. 35, partition walls 52 and 52B having discharge portions (e.g., nozzles) 53 are closed so as to close the upper portions of the pressure chambers 51, and the upper surfaces of the partition walls 52A. Bond or bond to The partition 52B is made of, for example, a sheet-like member (so-called nozzle sheet), and can be formed of, for example, a metal such as nickel or stainless steel or a required material such as a Si wafer. The electrostatic drive fluid discharge device 4 of the present invention is obtained via the above-described process.

Further, by adjusting the viscosity of the photocurable resin, the sealing member 45 is not formed by the metal sputtering of the opening 44 of the diaphragm 17 described in FIG. 31, and the sealing member is used using this photocurable resin. 45 can be formed and sealed.

According to the fluid drive device 3 according to the present embodiment, the diaphragm 17 is bent by the electrostatic force, and the restoring force is the driving force, so that the microfluid can be precisely controlled and supplied. When the auxiliary strut 23 is provided directly below the middle of the diaphragm 17, the length between the struts 21 of the diaphragm 17 even if the diaphragm 17 is made thin or the length of the short side of the diaphragm 17 is increased. Is shorter in appearance and the repulsive force of the diaphragm 17 can be increased, so that the required driving force can be obtained.

In this configuration, the diaphragm 17 is supported by the plurality of struts 21 integral with this, and the opening 44 for etchant introduction at the time of etching the sacrificial layer pattern 43 in the vicinity of the strut 21 is provided. Thus, in the formation of the space 31 between the diaphragm 17 and the substrate side electrode 12 having a long side of about 0.5 mm to 3 mm and a short side of about 15 μm to 100 μm, the sacrificial layer under the diaphragm 17 is formed. Since the space 31 formed by removing the pattern 43 can be etched toward the short side, etching can be performed in a short time, and at the same time, the space 31 under each adjacent diaphragm 17 can be simultaneously etched. Makes it possible to form the precision nicely. Therefore, it is possible to provide the fluid drive device 3 which secures the driving force for the fluid and enables high density.

By forming the lower substrate side electrode 12 as a common electrode and forming the upper diaphragm side electrode 15 as a plurality of independent electrodes, the lower surface of the diaphragm 17 can be formed flat. In the case where the lower substrate side electrode 12 is used separately, the step due to the thickness of the electrode appears as the step of the diaphragm 17, so that the tensile stress of the diaphragm 17 is alleviated to the step so that the tensile stress is reduced. It does not work effectively. On the other hand, the diaphragm 17 electrode made of a silicon nitride (SiN) film and the diaphragm side electrode 15 made of polycrystalline silicon (Si) pass through the third insulating film 16 on the lower surface side formed by the stepped portion of the diaphragm 17. Since the diaphragm side electrode 15 is closely contacted and arrange | positioned, even if the diaphragm 17 has a step part, the tension of the diaphragm 17 is not absorbed by a step part.

In addition, when the vertical relationship between the diaphragm 17 made of a silicon nitride (SiN) film and the diaphragm side electrode 15 made of polycrystalline silicon (Si) is reversed, that is, the diaphragm 17 made of a silicon nitride film is formed first. When the diaphragm side electrode 15 of polycrystalline silicon is formed thereon, the diaphragm 17 can be flattened, but the voltage applied between the substrate side electrode 12 and the diaphragm side electrode 15 has a relative dielectric constant. Since it is distributed also to this high SiN film, the effective voltage which acts on the space 31 of the lower surface of the diaphragm 17 and the upper surface of the board | substrate side electrode 12 falls, and electrostatic attraction falls accordingly, and the displacement amount of the diaphragm 17 also changes Since it lowers, it is disadvantageous when it aims at low power consumption driving.

When the fluid 61 supplied to the pressure chamber 51 is a liquid, if the part where the liquid contacts is a conductor, bubbles may be generated from the surface of the conductor in the liquid 61 or the surface of the conductor may corrode. In this case, since the diaphragm 17 is provided on the diaphragm side electrode 15, and the surface of the diaphragm 17 is covered with the 4th insulating film 18, such a problem does not arise.

When the fluid 61 is a liquid, the fourth insulating film 18 of the hydrophilic film is formed on the surface of the diaphragm 17, so that the liquid 61 can be smoothly introduced into the pressure chamber 51. have. In the case where the fluid 61 is a gas, the fourth insulating film 18 resistant to the gas is formed on the surface of the diaphragm 17 so that the diaphragm 17 does not invade with the gas.

According to the manufacturing method of the fluid drive device 3 according to the present embodiment, the sacrificial layer 41 and the diaphragm 17 are vapor-deformed to produce the following effects. The uniformity of the space | interval between electrodes and the film thickness of the diaphragm 17 become high, and the fluctuation | variation of the operating voltage between each diaphragm 17 becomes small. The flatness of the surface of the diaphragm 17 becomes high. Control of the electrode thickness and the film thickness of the diaphragm 17 becomes easy, and the diaphragm 17 of the desired film thickness can be made easily by film-forming time and temperature. Since it can be easily produced by a general semiconductor process, it is also excellent in mass production.

An opening 44 is formed in the vicinity of the support 21, and the sacrificial layer pattern 43 is etched away through the opening 44, so that the space between the diaphragm 17 and the substrate-side electrode 12 can be accurately formed. 31). Since the opening part 44 is formed in multiple numbers along the longitudinal direction of the diaphragm 17, the etching of the sacrificial layer pattern 43 is made in the short side direction of the diaphragm 17, and can shorten an etching time.

According to the electrostatic drive fluid discharge device 4 according to the present embodiment, by providing the fluid drive device 3 described above, the discharge portion 53 of the fluid 61 and the nozzle in this embodiment can be arranged at high density. At the same time, a small amount of fluid can be precisely controlled and supplied with high driving force.

The electrostatic drive fluid discharge device 4 is a pressure chamber 51, and a plurality of high pressure chambers, medium pressure chambers, and low pressure chambers are provided, and the pressure chambers 51 are connected to prevent backflow between the pressure chambers 51. It also includes a configuration in which a valve is arranged so that fluid flows with a pressure difference. One example may be the same configuration as that of the electrostatic drive fluid discharge device 1 described with reference to FIG.

Although the electrostatic drive fluid discharge device 4 is not shown in the drawing, when a gas is used as the fluid, the electrostatic drive fluid discharge device 4 can be configured by basically providing a valve at a discharge port outside the pressure chamber 51.

In the present invention, a partition structure having a fluid drive device 3 including a diaphragm 17, a pressure chamber 51 of a fluid, and a discharge part (for example, a nozzle) 53 by surface micromachining without bonding. It becomes possible to manufacture the electrostatic drive fluid discharge device 4 consisting of 54. Since the standard semiconductor process can be used, including the step of etching away the sacrificial layer pattern 43 from the opening 44 provided in the vicinity of the support 21, the fluid drive device 3 and the electrostatic drive fluid discharge device 4 can be used. The cost can be reduced.

In addition, the partition structure 54 having a discharge part (for example, a nozzle) 53, a pressure chamber 51, and a fluid supply flow path (not shown) formed separately on the fluid drive device 3 is joined to the electrostatic force. The drive fluid discharge device 4 may be manufactured. As the openings 44, for example, as described with reference to Fig. 19, a plurality may be formed in the vicinity of one support 21.

The fluid drive device of the present invention is formed so that the diaphragm-side electrode extends to reach a part of the support column bottom portion through the support column, or extends between the support pillars, so that the diaphragm reaches the entire support column bottom portion. The amount of electric charge stored in the bottom portion of the support pillar that does not contribute to the deformation of the diaphragm is smaller than the configuration in which the side electrodes are formed, and the amount of unnecessary power consumption is reduced. In addition, the diaphragm-side electrode is formed to extend to reach a part of the bottom portion of the support column through the support column, and the diaphragm strength is higher than that of the diaphragm-side electrode formed so as not to be applied to the support column. Since only the part becomes thick, there is an advantage that the supporting column becomes rigid.

Since the manufacturing method of the fluid drive device of this invention includes the process of forming the diaphragm side electrode through the 2nd insulating film in the upper part of the sacrificial layer pattern, the side wall side of the sacrificial layer pattern, and the bottom part of the support pillar formation area | region, Since the side electrode extends to reach a part of the bottom of the support pillar through the support pillar, the amount of charge stored in the bottom of the support pillar that does not contribute to the deformation of the diaphragm than the configuration in which the diaphragm side electrode is formed to cover the entire bottom of the support pillar. It is possible to form a configuration in which the amount of power consumption is reduced, which is reduced. In addition, the strength of the diaphragm becomes thicker than that of the diaphragm side electrode rather than the configuration in which the diaphragm side electrode is not applied to the support column, so that the support column can be configured to be rigid.

Since the manufacturing method of the fluid drive device of this invention comprises the process of forming the diaphragm side electrode through the said 2nd insulating film on the said sacrificial layer pattern containing between the said support pillar formation areas, the whole support pillar bottom part is provided. The amount of electric charge stored in the bottom portion of the support pillar that does not contribute to the deformation of the diaphragm is smaller than that of the diaphragm-side electrode formed so as to reduce the amount of power consumption unnecessarily.

Since the electrostatic drive fluid discharge device of the present invention includes the fluid drive device of the present invention, it can have the advantages of the fluid drive device of the present invention described above, and has a high fluid drive force, and also has a discharge portion of the fluid, For example, there is an advantage that it is possible to provide this kind of electrostatic drive fluid discharge device in which a nozzle as a liquid and a gas exit outlet are densified.

Since the manufacturing method of the electrostatic drive fluid discharge device of the present invention includes the manufacturing method of the fluid drive device of the present invention, it is possible to provide the advantages related to the manufacturing method of the fluid drive device of the present invention described above, and Such an electrostatic drive fluid discharge device can be manufactured with high accuracy. Moreover, for example, the surface micromachine which does not use bonding enables the production of an electrostatic drive fluid discharge device such as an inkjet printer head having a diaphragm, a pressure chamber, a discharge part (nozzle, a discharge port) and the like. There is an advantage to say.

The method of manufacturing the fluid drive device and the fluid drive device of the present invention and the method of manufacturing the electrostatic drive fluid discharge device and the electrostatic drive fluid discharge device are intended for supplying or discharging a liquid having a small capacity (about a picoliter or less). Applicable to the first half. For example, ink jet printer head for civil use, polymer such as organic EL for industrial use, low molecular organic material coating device, printed circuit board printing device, solder bump printing device, three-dimensional modeling device, chemical solution as μTAS (Micro Total Analysis Systems), its It can be applied to a supply head for precisely controlling and supplying the external liquid with a micro unit of pl (piccoliter) or less, or a supply head for precisely controlling and supplying gas with a small amount of precision. The fluid drive device 10 can also be applied to, for example, a drive source of a cooling fluid pump of a central processing unit (CPU) of a computer.

Claims (8)

A diaphragm for imparting a pressure change to the fluid, A diaphragm side electrode provided on the diaphragm by driving the diaphragm; A substrate side electrode provided to face the diaphragm side electrode; A space provided between the diaphragm side electrode and the substrate side electrode; In the fluid drive apparatus provided with the support column which supports the said diaphragm side electrode through the said space with respect to the said board | substrate side electrode, And the diaphragm side electrode extends to reach a portion of the bottom of the support column through the support column. Forming a substrate side electrode on the substrate; Forming a first insulating film on the substrate side electrode; Forming a sacrificial layer pattern for forming a space in a region excluding the support pillar forming region on the first insulating layer; Forming a second insulating film covering the sacrificial layer pattern; Forming a diaphragm side electrode on the sacrificial layer pattern and on a sidewall of the sacrificial layer pattern and a part of a bottom portion of the support pillar forming region through the second insulating film; Forming a third insulating film covering the diaphragm side electrode; Forming a diaphragm for imparting a pressure change to the fluid on the third insulating film; The sacrificial layer pattern is removed to form a space in the region from which the sacrificial layer pattern is removed, and the second insulating film, the diaphragm side electrode, the third insulating film, and the diaphragm are formed in the support pillar formation region formed in the space side portion. And a step of forming a support column in said support column formation region. A diaphragm for imparting a pressure change to the fluid, A diaphragm side electrode provided on the diaphragm by driving the diaphragm; A substrate side electrode provided to face the diaphragm side electrode; A space provided between the diaphragm side electrode and the substrate side electrode; It has a support column which supports the said diaphragm side electrode through the said space with respect to the said board | substrate side electrode, The diaphragm side electrode extends to reach a portion of the bottom of the support pillar through the support pillar, And a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid is formed on the diaphragm. Forming a substrate side electrode on the substrate; Forming a first insulating film on the substrate side electrode; Forming a sacrificial layer pattern for forming a space in a region excluding the support pillar forming region on the first insulating layer; Forming a second insulating film covering the sacrificial layer pattern; Forming a diaphragm side electrode on the sacrificial layer pattern and on a sidewall of the sacrificial layer pattern and a part of a bottom portion of the support pillar forming region through the second insulating film; Forming a third insulating film covering the diaphragm side electrode; Forming a diaphragm for imparting a pressure change to the fluid on the third insulating film; The sacrificial layer pattern is removed to form a space in the region from which the sacrificial layer pattern is removed, and the second insulating film, the diaphragm side electrode, the third insulating film, and the diaphragm are formed in the support pillar formation region formed in the space side portion. Forming a support pillar in the support pillar formation region by And forming a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid through the third insulating film on the diaphragm. A diaphragm for imparting a pressure change to the fluid, A diaphragm side electrode provided on the diaphragm by driving the diaphragm; A substrate side electrode provided to face the diaphragm side electrode; A space provided between the diaphragm side electrode and the substrate side electrode; In the fluid drive apparatus provided with the support column which supports the said diaphragm side electrode through the said space with respect to the said board | substrate side electrode, And the diaphragm side electrode extends between the support pillars. Forming a substrate side electrode on the substrate; Forming a first insulating film on the substrate side electrode; Forming a sacrificial layer pattern for forming a space in a region excluding the support pillar forming region on the first insulating layer; Forming a second insulating film covering the sacrificial layer pattern; Forming a diaphragm side electrode on the sacrificial layer pattern including the support pillar forming region through the second insulating film; Forming a third insulating film covering the diaphragm side electrode; Forming a diaphragm for imparting a pressure change to the fluid on the third insulating film; A space is formed in the region where the sacrificial layer pattern is removed by removing the sacrificial layer pattern, and the support pillar is formed by the second insulating film, the third insulating film, and the diaphragm in the support pillar forming region formed in the space side part. And a step of forming a support pillar in the region. A diaphragm for imparting a pressure change to the fluid, A diaphragm side electrode provided on the diaphragm by driving the diaphragm; A substrate side electrode provided to face the diaphragm side electrode; A space provided between the diaphragm side electrode and the substrate side electrode; It has a support column which supports the said diaphragm side electrode through the said space with respect to the said board | substrate side electrode, The diaphragm side electrode extends between the support pillars, And a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid is formed on the diaphragm. Forming a substrate side electrode on the substrate; Forming a first insulating film on the substrate side electrode; Forming a sacrificial layer pattern for forming a space in a region excluding the support pillar forming region on the first insulating layer; Forming a second insulating film covering the sacrificial layer pattern; Forming a diaphragm side electrode on the sacrificial layer pattern including the support pillar forming region through the second insulating film; Forming a third insulating film covering the diaphragm side electrode; Forming a diaphragm for imparting a pressure change to the fluid on the third insulating film; The sacrificial layer pattern is removed to form a space in the region from which the sacrificial layer pattern is removed, and the support pillar is formed by the second insulating film, the third insulating film, and the diaphragm in the support pillar forming region formed in the space side portion. Forming a support column in the area; And forming a pressure chamber having a supply portion of the fluid and a discharge portion of the fluid through the third insulating film on the diaphragm.

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