JPH0714479A - Substrate conducting device and pressure detecting device, and fluid delivery device and ink jet head employing the devices - Google Patents

Abstract

PURPOSE:To provide a conducting section small in area, but high in accuracy, make processes easy, and prepare a diaphragm for the conducting device and a diaphragm for the pressure device in a lump by a same process in the electrode conducting device. CONSTITUTION:In the pressure detecting device having a three layer structure composed of a glass layer 82, a silicone layer 81 and a glass layer 83, a silicon substrate 81 is formed with a diaphragm 811 with a projection, and electricity is conducted between an electrode 812 over a glass and the electrode 813 of the silicon substrate when the substrate is joined. In the pressure detecting device, two electrodes 87 and 89 are formed over a glass substrate 82, and when the pressure of an projected section 86 over a valve diaphragm 84 is equal to or more than a specified pressure, electricity is conducted between combteeth electrodes 87 and 89 over the glass substrate 82 via an electrode 88.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conducting device for a central substrate and an upper substrate by applying micromachining such as micromachining and bonding. It also relates to a pressure switch for detecting the pressure of fluid and gas, and a valve for controlling the flow rate of fluid. Further, the present invention relates to an ink jet head having a vertical conduction structure of electrodes and a fluid ejection device having a vertical conduction structure and a valve for controlling a flow rate.

[0002]

2. Description of the Related Art Conventionally, a substrate conduction device using a thin film forming technique has been disclosed in Nikkei Electronics, page 151, August 21, 1989, or the Institute of Electrical Engineers of Japan (Hei 2, 110 Vol. 3).
No. 205, page 205), a method of taking out electrodes by using solder or conductive epoxy, or a method of melting metal films at the time of joining substrates to each other. FIG. 14 shows a sectional view of a conventional example. The substrate 121 is generally a single crystal silicon substrate. Substrate 121 and substrate 122 such as glass
Are anodically bonded. The insulating film 123 is used to insulate the substrate, a conductive adhesive 125 is formed in order to establish electrical continuity with the electrode 124 formed on the glass substrate, and a signal is taken out by the lead wire 126 to the outside.

FIG. 15 shows an example of a pressure detecting device using a conventional thin film forming technique. The thin film 131 made of single crystal silicon or the like, the upper support substrate 132, and the lower support substrate 133 are bonded together. The diaphragm 134 is formed on the thin film 131, the pressure change of the input port 135 is transmitted to the pressure chamber 136, and the diaphragm 134 moves up and down due to the pressure change. With the electrode 138 formed on the thin film plate and the electrode 137 formed on the upper support substrate, since the diaphragm 134 moves up and down, the electrode 137 and the electrode 138 can be conducted and detected when the pressure exceeds a certain pressure.

A conventional fluid discharge device is disclosed in Japanese Patent Laid-Open No. 05-248.
As seen in Japanese Patent Publication No. 356, the detection is performed through an electrode formed on the outlet valve.

A conventional ink jet head is disclosed in Japanese Patent Application Laid-Open No. 05-2005.
The electrodes are made to face each other as in Example 8 of 050601 publication.

[0006]

However, it is difficult for the conventional board conduction device to bond a small area with high precision.
Further, there is a drawback in that an adhesive having a low viscosity spreads laterally due to a capillary phenomenon and short-circuits when there are a plurality of electrodes, and an adhesive having a high viscosity cannot conduct the lower electrode well. Therefore, it is difficult to reduce the size. Further, there is a drawback that the manufacturing time is long because a step of applying the adhesive is required. Not suitable for batch processing.

Further, when the electrodes are pulled out from different substrates, there is a possibility that the structure of the contact portion becomes complicated and conduction failure occurs due to the step difference between the substrates.

In the pressure detecting device, it is difficult to form an electrode on the thin film, and there is a problem that the electrode is broken when the electrode is formed on the step. Further, when the diaphragm thickness becomes thin, there is a problem that the diaphragm is distorted due to the stress due to the electrodes, and correct detection cannot be performed.

In the fluid discharge device, when the pressure detecting device is attached to the output valve, the electrodes are provided on the output valve diaphragm, so that the diaphragm is stressed and the valve characteristics deteriorate. Further, since the diaphragm portion has a large step difference with its surroundings, it is very difficult to form an electrode.

The ink jet head has a problem that it is difficult to connect electrodes to the outside in the case of the conventional example.

[0011]

According to another aspect of the present invention, there is provided a substrate conduction device comprising: (1) a laminated substrate including a supporting substrate, a thin film plate, and the counter electrode formed on the thin film plate and the supporting substrate. When the elastic plate and the protrusions are provided on the elastic plate and the three substrates are stacked, the thickness of the electrodes formed by the protrusions becomes higher than that on the plane, and a certain stress is applied between the supporting substrate and the thin film plate. It is characterized in that the electrodes of the counter electrodes are brought into contact with each other.

(2) In a laminated substrate composed of a supporting substrate, a thin film plate, and a counter electrode formed on the thin film plate and the supporting substrate, at least one of the thin film plate and the supporting substrate is provided with an elastic plate, and two elastic plates are provided. It is characterized in that when the substrates are stacked, the supporting plate and the electrodes of the counter electrodes of the thin film plate are brought into contact with each other with a certain stress by the elastic plate.

(3) In a laminated substrate comprising a supporting substrate, a thin film plate, and a counter electrode formed on the thin film plate and the supporting substrate, at least one of the thin film plate and the supporting substrate is provided with a recessed portion, It is characterized in that the supporting substrate and the electrodes of the counter electrodes of the thin film plate are brought into contact with each other by utilizing the ductility of the metal in the recessed portion.

(4) The conducting device according to the means 3 is characterized in that the depth of the recess is 0 to 0.5 μm shallower than the total thickness of the electrodes.

(5) A three-layer substrate including a supporting substrate, a thin film plate, and a holding substrate, which are laminated on the thin film plate and counter electrodes formed on the supporting substrate. A protrusion is provided on the upper surface, the supporting substrate and the electrodes of the counter electrodes of the thin film plates are brought into contact with each other at the protrusion, and a hole is formed in the holding substrate at a position facing the elastic plate. .

(6) In a three-layer substrate including a supporting substrate, a thin film plate, and a holding substrate stacked on the thin film plate and counter electrodes formed on the supporting substrate, an elastic plate and an elastic plate are formed on the thin film plate. Protrusions are provided on the upper surface, and the supporting substrate and the electrodes of the counter electrodes of the thin film plates are electrically connected by the contact parts by a certain contact stress so that the thin film plate or the holding substrate is not stressed by the pressure difference. In addition, it is characterized in that a concave cutout portion that communicates with the outside air from the elastic plate portion is provided on the surface facing the support substrate.

(7) In a substrate comprising a support substrate, a thin film plate, and a counter electrode formed on the thin film plate and the support substrate, the thin film plate is provided with minute recesses of 1 mm 2 or less. It is characterized in that an electrode formed on the plate is formed in a floating form above the recess, and the supporting substrate and the counter electrode of the thin film plate are brought into contact with each other with a certain stress.

(8) In the substrate conduction device according to means 1 to 7, borosilicate glass is used for the supporting substrate and the holding substrate, single crystal silicon is used for the thin film plate, and anisotropic etching is performed on the single crystal silicon. The thin elastic plate is formed by using the insulating film, the electrode is formed on the insulating film, and the glass-silicon anodic bonding or the glass-silicon-glass anodic bonding is performed to form them all at once.

The pressure detecting device of the present invention is (9) a pressure detecting device comprising a supporting substrate, a thin film plate and a diaphragm, wherein a protrusion formed on the diaphragm, an electrode formed on the protrusion, and It is characterized in that it is composed of at least two electrodes formed on the surface facing the protrusion, and the diaphragm is deformed by a certain pressure or more to push up the protrusion and the two electrodes come into contact with each other.

(10) In a pressure detecting device composed of a supporting substrate, a thin film plate, and a diaphragm, the pressure detecting device is formed on the diaphragm or on the same plate having a protrusion formed on the supporting substrate and a surface facing the protrusion. Or at least two electrodes are formed, and a contact portion between the electrodes is formed on a surface facing the protrusion via a space, and when the pressure exceeds a certain level, the protrusion causes the electrodes to contact each other. Characterized by contact.

(11) In a pressure detecting device composed of a supporting substrate, a thin film plate, and a diaphragm, two electrodes formed on the supporting substrate are arranged symmetrically with respect to the center of the diaphragm. To do.

(12) In the pressure detecting device according to the means 10 and 11, the electrodes are formed in a comb shape, the two electrodes are arranged so as to intersect each other, and a plurality of electrodes are simultaneously formed when the electrodes contact each other. The feature is that the electrodes are conductive.

(13) In the pressure detecting device according to means 9 to 12, borosilicate glass is used for the supporting substrate, single crystal silicon is used for the thin film plate, the diaphragm is formed by anisotropic etching, and insulation is performed. The method is characterized in that after forming the film and the insulating film, the electrode is formed, and then the supporting substrate and the holding substrate are anodically bonded together to form them all at once.

(14) The pressure detecting device according to the means 9 to 13 is characterized in that it has at least one of the substrate conduction devices according to the means 1 to 8.

(15) In the pressure detecting device having both the means 8 and the means 13, the elastic plate and the diaphragm are simultaneously formed in the same step when anisotropically etching the thin film plate.

The fluid discharge device of the present invention comprises: (16) a holding substrate having an input valve, a drive unit, and an output valve formed on a thin film plate, and a flow path formed by laminating the thin film plate with the input valve.
And a fluid discharge device for laminating a support substrate on which electrodes are formed on the opposite surface of the thin film plate and the support substrate, comprising a substrate conduction device of means 1 to 8 or a pressure detection device of means 9 to 14. Is characterized by.

In the ink jet head of the present invention, (17) a thin film plate provided with a vibrating plate and electrodes, a holding substrate having drive electrodes on the surface facing the vibrating plate, and a flow path formed by sandwiching the thin film plate. An inkjet head having a supporting substrate is characterized by having at least one of the substrate conducting devices of the means 1 to 9.

[0028]

【Example】

(Embodiment 1) FIG. 1 shows a substrate conduction device according to a first embodiment of the present invention. (A) is sectional drawing, (b) is a top view. As the thin film substrate 11, a single crystal silicon substrate having a size of 3 inches to 6 inches and a double-sided polishing thickness of 200 μm to 400 μm is often used when forming a small structure by the micromachining technique. For the upper holding substrate 12, borosilicate glass which has almost the same expansion coefficient and can be easily and accurately bonded to single crystal silicon by anodic bonding is often used. The elastic plate 13 and the protrusions 14 are integrally formed on the thin film substrate by performing anisotropic etching with an etching solution such as KOH or TMAH. Protrusion 14
An electrode 16 is formed on the holding substrate 12 by sputtering, plating, printing or the like, and the electrode 15 is also formed on the holding substrate 12. As the electrodes, gold, two-layer, three-layer structure electrodes,
Alternatively, a high contact material such as a platinum alloy electrode can be used. The height of the protrusion becomes higher than that of the substrate 11 by the thickness of the electrodes 15 and 16. Since it is possible to control the thickness of the electrode in the vicinity of 0.1 μm, it is possible to accurately form a minute height. Then, when the substrate 11 and the holding substrate 12 are joined together, the electrodes 15 and 16 can come into contact with each other and become conductive. The contact pressure of the electrode can be arbitrarily selected according to the diameter and thickness of the elastic plate 13, and the contact pressure can be easily calculated. Further, since holes can be formed in the elastic plate by anisotropic etching, the elastic plate can be formed in the shape of four beams and the rigidity can be reduced, so that conduction can be achieved in a smaller area.

It is also possible to form a plurality of electrodes on one projection and to simultaneously conduct a plurality of electrodes.

(Embodiment 2) FIG. 2 shows a sectional view of a substrate conduction device according to a second embodiment of the present invention. The shape 23 is obtained by anisotropically etching the single crystal silicon substrate 21.
Further, the glass substrate 22 is etched to obtain the shape 26. Electrodes 25 and 28 are formed on the single crystal silicon substrate 21, and electrodes 24 and 27 are formed on the glass substrate 22, respectively. Total thickness of electrodes 25 and 28 and electrode 2
4 and electrode 27 have a total thickness of 0 to 0.5 micron, preferably 0.01 to 0.
Only 5 microns thick. Therefore, when the single crystal silicon substrate 21 and the glass substrate 22 are bonded together, the elasticity of the electrodes allows the electrodes to come into contact with each other and the bonding is also possible. Therefore, it is possible to bring the electrodes on the silicon substrate onto the glass substrate. Further, since the area of the contact surface of the electrode is not required, the contact of the electrode is possible if the lateral width is about 0.5 mm.

(Embodiment 3) FIG. 3 shows a sectional view of a substrate conduction device according to a third embodiment of the present invention. The single crystal silicon substrate 31 is anisotropically etched to form the elastic plate 33 and the protrusion 34. After that, the electrode 35 is formed on the silicon substrate 31.
To form. An electrode 36 is formed on the glass substrate 32.
Air holes 38 are provided in the glass substrate 37. By bonding the single crystal silicon substrate 31, the glass substrate 32, and the glass substrate 37, respectively, the electrode 35 and the electrode 36 can be formed.
Take contact.

(Embodiment 4) FIG. 4 is a sectional view of a substrate conduction device according to a fourth embodiment of the present invention. The basic structure is shown in Figure 3.
Same as the above, but the air holes 41 are formed in the single crystal silicon substrate by anisotropic etching to form the air holes at the same time as the elastic plate 33.

(Embodiment 5) FIG. 5 shows a sectional view of a substrate conduction device according to a fifth embodiment of the present invention. An electrode 53 is formed on the single crystal silicon substrate 51. Then, a recess 55 is provided. In addition, an electrode 54 is provided on the glass substrate 52.
Are formed. By bonding the single crystal silicon substrate 51 and the glass substrate 52, the electrodes 53 and 54 are brought into conduction while having a certain contact stress. If the electrode 53 alone is weak in terms of strength as an elastic plate, a thin film of a material having a large Young's modulus such as silicon oxide, silicon carbide, or silicon nitride may be formed under the electrode 53 to increase rigidity. is there. In this case, since the elastic body is very thin, the contact stress is small, and the area of the conducting portion is very small.

6 (a) to 6 (d) are sectional views showing an example of a manufacturing process of the substrate conduction device according to the fifth embodiment of the present invention. (A) is an example in which the single crystal silicon substrate 61 is etched by an etchant such as KOH. In (b), the entire surface of the single crystal silicon substrate 61 is oxidized, photolithography is performed, and the portions other than the oxide film 62 are etched. (C) shows the electrode 63 formed in the state of (b). In this case, there are various methods of forming such as using mask sputtering, performing photolithography after performing the entire surface sputtering, and performing lift-off. In (d), the oxide film 62 is removed from (c), and anisotropic etching is performed using a KOH solution to form a V-shaped groove 65.

(Embodiment 6) FIG. 7 shows a sectional view of a pressure detecting device according to a sixth embodiment of the present invention. (A) is an example of a pressure switch, and is a sectional view when a pressure is 0 Pa. Silicon substrate 71, diaphragm 74, protrusion 75, protrusion 7
An electrode 78 is formed on the upper part of 5. Further, a glass substrate 72, a reference electrode 79 and a detection electrode 710 are formed, and a glass substrate 73 and a pressure introducing port 77 are provided. The silicon substrate 71, the glass substrate 72, and the glass substrate 73 are anodically bonded. In operation, when pressure is applied to the pressure introducing port 77, pressure is applied to the pressure chamber 76 and the diaphragm 74 is deformed. FIG. 7B is a sectional view when the pressure switch of this embodiment is turned on.
When a pressure above a certain level is applied to the pressure chamber 76, the electrode 78
The reference electrode 79 and the detection electrode 710 are electrically connected via the. For example, if the detection electrode 710 is floating and the reference electrode 79 is 5 volts, the detection electrode 710 is floating in the state of (a) and a signal of 5 volts is taken out in the state of (b).
The pressure can be easily detected on the circuit side.

(Embodiment 7) FIG. 7C shows a sectional view of a pressure detecting device according to a seventh embodiment of the present invention applied to a valve. A reference electrode 719 and a detection electrode 720 are formed on a silicon substrate 711, a glass substrate 713, and a glass substrate 712. A diaphragm 714, a protrusion 715, a valve protrusion 721, and an electrode 718 are formed on a silicon substrate 711. The valve protrusion 721 is formed with an oxide film or a nitride film so as not to be bonded to the glass substrate 713. When pressure is applied from the input port 716, the diaphragm 71
4 is deformed, and the fluid becomes the valve protrusion 721 and the glass substrate 713.
Fluid can flow through the gap. When the pressure on the input side exceeds a certain value, the electrode 718, the reference electrode 719, and the detection electrode 720 become conductive. Regarding the pressure at which the pressure switch operates, the diameter and thickness of the diaphragm 714, the electrode 71
Determined by a gap of 8. By forming the reference electrode 719 and the detection electrode 720 in a comb shape and arranging them so as to intersect with each other, it is easy to make contact even when the electrode 718 is inclined.

It is also possible to form the protrusion 715 on the glass 712 without forming the protrusion 715 on the silicon substrate.

In the valve having the shape shown in FIG. 7C, the flow rate is uniquely determined according to the pressure difference. Therefore, when the pressure is equal to or higher than a certain pressure, or when the flow rate is equal to or higher than a certain flow rate, the pressure switch is turned on to sound an alarm or suppress the pressure on the input side.

(Embodiment 8) FIG. 8 shows a pressure detecting device according to an eighth embodiment of the present invention. 8A is a top view, and FIG. 8B is a cross-sectional view taken along the line AA in FIG. A contact diaphragm 811 having a valve diaphragm 84, a protrusion 86, a valve protrusion 85, an electrode 88 having a two-layer structure of an insulating layer and an electrode layer on the valve protrusion 85 on the silicon substrate 81, and a protrusion provided at another place. , The insulating layer and the electrode layer on it 2
An electrode 813 having a layered structure is formed. Glass substrate 82
A reference electrode 87 and a detection electrode 88 are formed on the glass substrate 83, and a hole 810 is formed in the glass substrate 83. The reference electrode 87 and the detection electrode 88 are formed in a comb shape and are arranged so as to intersect each other.
The glass substrate 82, the silicon substrate 81, and the glass substrate 83 are anodically bonded. At that time, the electrode 812 and the electrode 89 are brought into contact with each other to establish conduction. The inflow port is 814. The electrode pad 813 is electrically connected to an external substrate or the like. When the place where the electrode extending from the electrode pad enters the glass substrate 82 is sealed with an adhesive, the electrode 88 portion is not contaminated with dust. The operation of the valve is the same as in FIG. The silicon substrate 81 is formed by making the elastic plate and the diaphragm have the same thickness.
4, the elastic plate 811, the protrusion 86, and the elastic plate 812 can be formed by the same etching process.

(Embodiment 9) FIG. 9 shows a sectional view of a pressure detecting device according to a ninth embodiment of the present invention. Silicon substrate 9
1 is etched to form the diaphragm 94 and the protrusion 97, and is joined to the glass substrate 93 having the hole 95, as in FIG. 7C. No electrodes are formed on the silicon substrate 91, but the reference electrode 98 and the detection electrode 99 are formed on the glass substrate 92. When pressure is applied to the pressure chamber 96, the electrode 9
When 8 is pushed upward and the pressure reaches a certain level or more, the reference electrode 98 and the detection electrode 99 come into contact with each other vertically. The formation of an electrode having a shape like the reference electrode 98 can be easily achieved by etching the sacrificial layer using a material such as silicon nitride as the sacrificial layer.

(Embodiment 10) FIG. 10 shows a silicon substrate portion of a pressure detecting device according to a tenth embodiment of the present invention.
(A) is a top view and (b) is a sectional view. A silicon substrate 101, a protrusion and an electrode 102 on the protrusion, a diaphragm 103, and an electrode 104 on the diaphragm are formed, and four electrodes extend from the center. This electrode 10
Since the stress of No. 4 extends in four directions from the center, it is possible to evenly apply the stress to the diaphragm 103. Therefore, the valve does not tilt and open or close.

In the case of this embodiment, four electrodes are provided so as to form a cross, but it is also possible to provide eight electrodes and arrange them concentrically.

(Embodiment 11) FIG. 11 is a sectional view showing a process for producing a single crystal silicon substrate of a valve provided with a pressure detecting device according to an eleventh embodiment of the present invention. Here, the single crystal silicon substrate 111 is a (100) plane silicon substrate. In the micromachining technique, generally, a photolithography technique is used to perform anisotropic etching with a 20 to 40% wtKOH solution, TMAH solution or the like using a thermal oxide film as an etching mask. In the figure, the dotted line shows the shape before etching, and the solid line shows the shape after etching.

(A) shows the shape after the primary etching.
The portion 112 where primary etching is performed is a diaphragm, and the etching portion 113 is a portion where an elastic plate is formed.

(B) shows the shape after the secondary etching.
Etching part 115 for obtaining substrate conduction forming part 117
And the shape of (b) is obtained by etching the etching part 114 for obtaining the valve part diaphragm 116. Further, at that time, the diaphragm 112 and the etching portion 113 etched in (a) have no mask of the thermal oxide film, and are etched as in (c).

(C) shows a shape after the third order, in which a gap 118 for pressure detection and a gap 119 for electrode conduction are formed.

(D) is formation of an insulating film. By providing the insulating film 1110 of the detecting portion and the insulating film 1111 of the vertical conducting portion, the insulating film 1110 is insulated from the silicon substrate, and thus no electric field is applied to the silicon substrate. Therefore, for example, even if the pressure is applied to the electrolyte, it does not affect the properties of the liquid.

By the electrode forming process (e), the electrode 1112 above the protrusion and the electrode 1113 above and below are obtained. The thickness of the electrode 1113 and the insulating film 1111 is higher than that of the flat portion of the silicon substrate 111. Therefore, when anodic bonding the glass substrate to the silicon substrate 111,
The stress is applied to the diaphragm 117, so that the conductive portion can be electrically contacted. The valve protrusion 1114 controls the fluid.

(Embodiment 12) An embodiment of the fluid discharge device of the present invention will be described below. In FIG. 12, (a) is a top view,
(B) is a cross-sectional view taken along line XX of (a), and (c) is a cross-sectional view taken along line X′-X ′ of (a).

An input valve diaphragm 147, a drive diaphragm 149 and an output valve diaphragm 1422 are collectively formed on the single crystal silicon substrate 141 by etching. The single crystal silicon substrate 141 is connected to the input port 145,
The glass substrate 142 provided with the output port 146, the glass substrate 143 serving as the lid of the input valve, and the glass substrate 144 serving as the lid of the output valve are joined by anodic bonding to form a fluid ejection device.

The input valve protrusion 148 and the output valve protrusion 1424 can be freely opened and closed without being joined to the glass 142 by forming a film or the like. When a voltage is applied to the piezoelectric element 1412 and the drive diaphragm 149 vibrates up and down, a pressure change in the flow path occurs, and the fluid flows through the arrow 1430.
The ejection is performed as indicated by arrows 1431, 1432, and 1433.

The electrode 1411 is electrically connected to the upper electrode of the piezoelectric element 1412. The piezoelectric element 1412 is bonded to the electrode 1410, and the lower electrode of the piezoelectric element 1412 and the electrode 1
410 is conducting.

Electrode pad 1413 and electrode pad 14
Reference numeral 14 is an outlet for the detection electrode. Electrode pad 14
An electrode 1415 extends from 13 to the single crystal silicon substrate 141, and an elastic plate 1425 is used to form an electrode 1418 on the glass.
And the electrode 1415 are electrically connected, and the electrode 1 on the glass substrate
417 is electrically connected to the electrode 1416. The electrodes formed on these silicon substrates 141 are the silicon substrates 14
It is advisable to provide an oxide film or the like between the two in order to insulate them. The air port 1426 connects the surface of the elastic plate 1425 opposite to the electrode surface to the outside air. The detection electrode 1419 and the detection electrode 1420 on the glass substrate 144 are the output valve mesas 1423.
When the output valve mesa 1423 contacts the glass 144 substrate by the upper and lower sides of the output valve diaphragm 1424, the electrodes on the output valve mesa 1423 are formed so as to intersect each other as shown in the figure or on the comb teeth. 1421
Short-circuits the detection electrode 1419 and the detection electrode 1420. Therefore, for example, + 5V is applied to the electrode 1413,
When the electrode 1414 is the detection electrode, the output valve mesa 1423
The upper electrode 1421 is the electrode 141 on the glass substrate 144.
9. When contacting the electrode 1420, + 5V is output to the detection electrode 1414. Therefore, the behavior of the output valve can be detected.

(Embodiment 13) An example of the ink jet head of the present invention is shown in FIG. In FIG. 13, (a) is a top view and (b) is an X-X sectional view. Only one dot is shown here for simplicity. Single crystal silicon substrate 1
The shape of 51 is formed by etching as shown in FIG. Then, both surfaces are bonded to the glass substrate 153 and the glass substrate 152 in a sandwiched manner. Ink enters from an input port 154 and an electrode 159 in a driving cavity 156.
The drive diaphragm 1512 vibrates due to the electrostatic drive force of the electrode 157 and the ink, and the ink is ejected through the ejection port 155.
Is discharged from. The drive electrode 157 is formed on the glass substrate 153. Further, the drive electrode 158 is formed on the glass substrate 153, and the protrusion 151 having an elastic plate is formed.
Electrode 151 on the glass which is an extension of drive electrode 158 at 0
1 and the electrode 159 on silicon are electrically connected to each other. The electrodes 159 are insulated from each other by interposing an oxide film or the like between the silicon substrate 152 and the electrodes 159 so that no potential is applied to the silicon substrate 151.

[0055]

As described above, the present invention has the following effects.

In the substrate conduction device, (1) since the diaphragm structure is used to establish conduction by anodic bonding, it is possible to make use of the features of the micromachining technology and to accurately produce a large number of vertical conductions at one time. is there. Also, the stress at the time of conduction is set to the diaphragm thickness,
Since the diameter and shape can be selected, it is easy to select a desired force. The thickness of the diaphragm can be as thick as 5 μm, and it is usually formed from 15 to 40 μm.
The contact stress can be reduced and the size can be reduced to 1 square millimeter or less. Further, a hole is formed in the diaphragm and 4
Since it is possible to further reduce the stress by forming a book beam, it is possible to further reduce the size.

(2) Since the single crystal silicon substrate and the glass substrate can be accurately etched, the ductility of the electrode is utilized, and the metal electrode is 0 to 0.5 micron, preferably 0.01 to
By forming it to a thickness of more than 0.5 micron and crushing it simultaneously at the time of joining, the electrical joining property of the metal and the metal is improved, and the up and down conduction can be easily obtained with high accuracy. Further, this method does not require an area, so that many electrodes can be conducted simultaneously.

(3) When forming the upper and lower conducting portions, the space sandwiched between the supporting substrate and the single crystal silicon substrate becomes a vacuum at the time of joining, so that negative pressure is applied to the elastic plate so that conduction cannot be lost. By providing a hole or a groove that conducts to the outside, atmospheric pressure is normally applied to the elastic plate to make a normal contact, and it is possible to form the upper and lower conducting parts.

(4) The thin film metal electrode or the silicon oxide film and the thin film metal film are used as the diaphragm. Therefore, the diaphragm thickness of about 1 micron can be easily formed by sputtering, vapor deposition or the like. Since the diaphragm thickness can be reduced, the diaphragm diameter can be reduced, and the proportion of the upper and lower conducting portions in the whole can be reduced. Therefore, it is possible to create many vertical connections in a small area by batch processing.

In the pressure detecting device, (5) since no electrode is formed on the diaphragm surface, it is possible to easily form an electrode without causing a phenomenon of electrode breakage due to a step when the electrode pattern is formed. Further, since the diaphragm is not stressed by the electrode pattern, the pressure can be accurately detected. The unevenness of the stress prevents the projection from tilting and hitting the electrode.
When a valve having this detection structure is used, the flow rate is uniquely determined according to the pressure difference. Therefore, when the pressure is equal to or higher than a certain pressure, or when the flow rate is equal to or higher than a certain flow rate, the pressure switch is turned on to sound an alarm or suppress the pressure on the input side. Further, when the protrusion is formed on the supporting substrate, the diaphragm becomes lighter, the inertia becomes smaller, and it is possible to create a pressure detecting device having good responsiveness.

(6) The process can be simplified because it is not necessary to form an electrode on the silicon protrusion. Therefore, it is possible to simplify the process and reduce the cost.

(7) Since the electrodes are formed in a comb-like shape and arranged so as to intersect with each other, it is possible to accurately detect even when the protrusions do not uniformly contact the electrodes.

(8) Since the pressure detection device and the vertical conduction structure can be collectively manufactured in the same process,
The process can be reduced and can be done accurately. In addition, since the micromachining technology is used, the shape of one product is usually made into a square by dicing.Therefore, by arranging the vertical conduction part at the corner of the pressure detection device, there is no waste and the vertical conduction is achieved without increasing the area. It is possible to create a pressure detecting device including a structure. Since the insulating film such as an oxide film can insulate the electrode and the silicon substrate, there is an advantage that the detection signal does not have a bad influence even if the liquid acting on the valve and the pressure detection switch is the electrolyte.

(9) By arranging the electrodes arranged on the diaphragm symmetrically with respect to the center of the diaphragm such as a cross so as not to affect the stress of the diaphragm, uneven stress is applied to the diaphragm. Because it does not take
Good valve characteristics can be obtained.

(10) In the fluid discharge device, since the electrode is not formed on the output valve diaphragm, there is no problem that the electrode is cut on the step, and the electrode can be easily formed. Since no electrode is formed on the diaphragm, no membrane stress is exerted, and it is possible to obtain good valve characteristics without adversely affecting the output valve characteristics. By making the electrodes comb-shaped,
Even if the output valve behaves in an unstable manner and comes into contact with the glass substrate, stable detection is possible because the probability of overlapping of the electrodes is high. In addition, the vertical conduction structure is suitable for miniaturization without increasing the overall size because it does not take up an area.

(11) In the ink jet head, since the electrodes can be taken out on the same plane, it is easy to mount the electrodes outside. In addition, since the part for conducting the vertical conduction can be collectively formed by etching, it is not necessary to increase the number of conducting steps, unlike the case of bonding. Further, since the thickness of the diaphragm of the conductive portion can be reduced as shown in (1), the overall size can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view and a top view of a substrate conduction device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a substrate conduction device according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a substrate conduction device according to a third embodiment of the present invention.

FIG. 4 is a sectional view of a substrate conduction device according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view of a substrate conduction device according to a fifth embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the process of the substrate manufacturing method in the fifth embodiment of the present invention.

FIG. 7 is a sectional view showing an example and operation of a pressure detecting device according to sixth and seventh embodiments of the present invention.

FIG. 8 is a top view and a sectional view of a substrate conduction device and a pressure detection device according to an eighth embodiment of the present invention.

FIG. 9 is a sectional view of a substrate conduction device according to a ninth embodiment of the present invention.

FIG. 10 is a top view and a sectional view of a silicon substrate portion of a pressure detecting device according to a tenth embodiment of the present invention.

FIG. 11 is a sectional view showing an example of a manufacturing process in the eleventh embodiment of the present invention.

FIG. 12 is a top view and a sectional view showing an example of a fluid ejection device according to a twelfth embodiment of the present invention.

FIG. 13 is a top view and a cross-sectional view showing an example of an inkjet head according to a thirteenth embodiment of the present invention.

FIG. 14 is a cross-sectional view of a conventional example of a substrate conduction device.

FIG. 15 is a sectional view of a conventional example of a pressure detection device.

[Explanation of symbols]

11 Thin Film Substrate such as Silicon Substrate 12 Upper Holding Substrate such as Glass Substrate 13 Diaphragm 14 Protrusion 15 Electrode 16 Electrode 21 Silicon Substrate 22 Glass Substrate 23 Shape 24 Electrode 25 Electrode 26 Shape 27 Electrode 28 Electrode 31 Silicon Substrate 32 Glass Substrate 33 Diaphragm 34 Protrusion 35 Electrode 36 Electrode 37 Glass substrate 38 Air hole 41 Air hole 51 Silicon substrate 52 Glass substrate 53 Electrode 54 Electrode 55 Recess 61 Silicon substrate 62 Oxide film 63 Electrode 65 V Groove shape 71 Silicon substrate 72 Glass substrate 73 Glass substrate 74 Diaphragm 75 Protrusion 76 Pressure chamber 77 Pressure inlet 78 Electrode 79 Reference electrode 710 Detection electrode 711 Silicon substrate 712 Glass substrate 713 Glass substrate 714 Diaphragm 715 Protrusion 716 Input port 71 Electrode 719 Reference electrode 720 Detection electrode 721 Valve protrusion 81 Silicon substrate 82 Glass substrate 83 Glass substrate 84 Valve diaphragm 85 Valve protrusion 86 Protrusion 88 Electrode 811 Contact portion diaphragm 812 Protrusion 813 Electrode 814 Inlet 91 Silicon substrate 92 Glass substrate 93 Glass substrate 94 Diaphragm 95 Hole 96 Pressure chamber 97 Projection part 98 Reference electrode 99 Detection electrode 101 Silicon substrate 102 Electrode 103 Diaphragm 104 Electrode 111 Silicon substrate 112 Primary etching part 113 Primary etching part 114 Etching part 115 Etching part 117 Etching part 118 Gap forming part 119 Gap forming portion 1110 Insulating film 1111 Insulating film 141 Single crystal silicon substrate 142, 143, 144 Glass substrate 145 Input 146 Output port 147 input valve diaphragm 148 input valve boss 149 driven diaphragm 1410,1411,1415,1416,1417,
1421 Electrodes 1412 Piezoelectric elements 1413, 1414 Electrode pads 1418 Projections 1419, 1420 Detection electrodes 1422 Output valve diaphragms 1423 Output valve mesas 1424 Output valve rings 1425 Elastic plates 1426 Air ports 1431, 1432, 1433 Arrows 151 Single crystal silicon 152, 153 Glass Substrate 154 Input port 155 Discharge port 156 Drive cavity 157, 158 Drive electrode 159 Electrode 1510 Projection 1511 Electrode on glass substrate 1512 Drive diaphragm

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // F04B 43/04 B 2125-3H G05D 7/06 Z 9324-3H

Claims (17)

[Claims] 1. A laminated substrate comprising a supporting substrate, a thin film plate, and one or more counter electrodes respectively formed on the thin film plate and the supporting substrate, wherein an elastic plate is provided on the thin film plate and a protrusion is provided on the elastic plate. A substrate conduction device, characterized in that the supporting substrate and the electrodes of the counter electrodes of the thin film plate are brought into contact with each other at the protrusions. 2. A laminated substrate comprising a support substrate, a thin film plate, and one or more counter electrodes each formed on the thin film plate and the support substrate, wherein an elastic plate is provided on at least one of the thin film plate and the support substrate. A substrate conduction device, wherein the elastic plate is provided to bring the supporting substrate into contact with electrodes of counter electrodes of the thin film plate. 3. A laminated substrate comprising a support substrate, a thin film plate, and one or more counter electrodes respectively formed on the thin film plate and the support substrate, wherein at least one of the thin film plate and the support substrate has a recessed portion. A substrate conduction device, characterized in that the support substrate and the electrodes of the counter electrodes of the thin film plate are brought into contact with each other at the recessed portion. 4. The substrate conduction device according to claim 3, wherein the depth of the recess is 0 to 0.5 μm shallower than the total thickness of the electrodes. 5. A laminated substrate comprising a supporting substrate, a thin film plate, a holding substrate, and one or more counter electrodes formed on the thin film plate and the supporting substrate, wherein the thin film plate is an elastic plate, and the elastic plate is on the elastic plate. Substrate conduction, characterized in that a protrusion is provided, the supporting substrate and the electrodes of the counter electrodes of the thin film plate are brought into contact with each other at the protrusion, and a hole is provided in the holding substrate at a position facing the elastic plate. apparatus. 6. A laminated substrate comprising a supporting substrate, a thin film plate, a holding substrate, one or more counter electrodes formed on the thin film plate and the supporting substrate, wherein the thin film plate is an elastic plate, and the elastic plate is on the elastic plate. A protrusion is provided, and the supporting substrate and the electrode of the counter electrode of the thin film plate are brought into contact with each other at the protrusion, and a recessed portion for conducting the outside air from the elastic plate portion to the thin film plate or the holding substrate faces the support substrate. A board conduction device characterized in that it is provided on the surface. 7. A substrate comprising a support substrate, a thin film plate, and one or more counter electrodes respectively formed on the thin film plate and the support substrate, wherein the thin film plate is provided with a recess and is formed on the thin film plate. A substrate conduction device, wherein a formed electrode is formed on the upper portion of the recess, and the supporting substrate and the electrode of the counter electrode of the thin film plate are brought into contact with each other. 8. The substrate conduction device according to claim 1, wherein borosilicate glass is used for the supporting substrate and the holding substrate, single crystal silicon is used for the thin film plate, and anisotropic etching is performed on the single crystal silicon. Is used to form the elastic plate,
A substrate conduction device comprising an insulating film and the electrode formed on the insulating film, and the support substrate and the holding substrate are anodically bonded together to form the electrode at one time. 9. A pressure detecting device comprising a supporting substrate, a thin film plate and a diaphragm, wherein a protrusion formed on the diaphragm, an electrode formed on the protrusion and a surface facing the protrusion are formed. A pressure detecting device comprising at least two electrodes. 10. A pressure detecting device comprising a supporting substrate, a thin film plate and a diaphragm, wherein at least two electrodes are formed on the diaphragm or on the supporting substrate and on a surface facing the protruding portion. And a contact portion between the electrodes is formed on a surface facing the protrusion via a space. 11. A pressure detecting device comprising a supporting substrate, a thin film plate, and a diaphragm, wherein two electrodes formed on the supporting substrate are arranged symmetrically with respect to the center of the diaphragm. Pressure detection device. 12. The pressure detecting device according to claim 10, wherein the electrodes are formed in a comb-like shape, and the two electrodes are arranged so as to intersect each other. 13. The pressure detection device according to claim 9, wherein borosilicate glass is used for the supporting substrate, single crystal silicon is used for the thin film plate, and the diaphragm is formed by anisotropic etching. A pressure detecting device characterized by forming an insulating film and the electrode on the insulating film, and forming the supporting substrate and the holding substrate by anodic bonding to form them all together. 14. The pressure detection device according to claim 9 to claim 13, further comprising at least one of the substrate conduction devices according to claim 1 to claim 8. 15. A pressure detecting device having a substrate conduction device according to claim 8 and a pressure detecting device according to claim 13, wherein the elastic plate and the diaphragm are simultaneously formed in the same step when anisotropically etching the thin film plate. A pressure detecting device characterized by being formed. 16. A holding substrate that forms an input valve, a drive unit, and an output valve on a thin film plate, and that forms a flow path by stacking with the thin film plate, and a support substrate that forms an electrode on the thin film plate. In a fluid ejection device laminated on the opposite side of the support substrate,
A substrate discharge device according to any one of claims 1 to 8 or a pressure detection device according to any one of claims 9 to 14, which is a fluid ejection device. 17. An ink jet head having a diaphragm and a thin film plate provided with an electrode, a holding substrate having a drive electrode on a surface facing the diaphragm, and a support substrate which forms a flow path by sandwiching the thin film plate, An inkjet head comprising at least one of the substrate conduction devices according to claim 1.