JP2008307769A - Liquid droplet discharge head, liquid droplet discharge device, method for manufacturing liquid droplet discharge head, and method for manufacturing liquid dropelt discharge device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-nozzle type liquid droplet discharge head in which a time constant of a drive circuit of an actuator is made small to reduce a delay of a liquid droplet discharge operation as much as possible in the liquid droplet discharge head having a plurality of nozzles capable of being concurrently driven, and to provide a liquid droplet discharge device, a method for manufacturing the liquid droplet discharge head and a method for manufacturing the liquid droplet discharge device. <P>SOLUTION: This liquid droplet discharge head 100 is equipped with a cavity substrate 3 and an electrode glass substrate 4 which is opposed to a diaphragm 8 with a gap 18 therebetween and has an individual electrode 17 for driving the diaphragm 8 formed thereon. An input wire 20 for inputting, from the external section, power to a driver IC 15 is formed on the electrode glass substrate 4, the driver IC 15 being adapted to supply a drive signal to the individual electrode 17. A part of the input wire 20 is formed to be in a lamination structure including a conductive oxide material and a metallic material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a droplet discharge head, a droplet discharge device, a method of manufacturing a droplet discharge head, and a method of manufacturing a droplet discharge device for discharging ink and other liquids. The present invention relates to a droplet discharge head, a droplet discharge device, a method for manufacturing a droplet discharge head, and a method for manufacturing a droplet discharge device.

As an apparatus for ejecting droplets, for example, an inkjet head mounted on an inkjet recording apparatus is known. In general, this inkjet head has a nozzle substrate formed with a plurality of nozzle holes for discharging ink droplets, an ejection chamber joined to the nozzle substrate and communicating with the nozzle holes, and an ink flow path such as a reservoir. And a cavity substrate, and is configured to eject ink droplets from selected nozzle holes by applying pressure to the ejection chamber. As a method for ejecting ink droplets in this way, an electrostatic driving method using electrostatic force, a piezoelectric method using a piezoelectric element, and a bubble jet (registered trademark) using a heating element are used.
There are methods.

Among these, in an electrostatic drive type inkjet head, a cavity substrate having a bottom plate of a discharge chamber as a vibration plate, and an electrode glass substrate on which an individual electrode facing the vibration plate with a predetermined gap (gap) is formed, It is the structure which joined. When ejecting ink droplets, a drive voltage is applied to the individual electrodes to be positively charged, and a drive voltage is applied to the corresponding diaphragm to be negatively charged. Then, the diaphragm is elastically deformed toward the individual electrode by the electrostatic attractive force generated at this time. When this driving voltage is turned off, the diaphragm is restored. At this time, the pressure inside the discharge chamber rises rapidly, and a part of the ink in the discharge chamber is discharged from the nozzle hole as an ink droplet.

In recent years, electrostatic drive inkjet heads have been increasing in nozzle density and multi-row for the purpose of high-speed printing and multi-color printing of high-resolution images. The number of chambers has increased, and the length of nozzle rows has been increasing. In addition, for the purpose of reducing the size of the ink jet head, a structure in which a driver IC for actuator control is embedded in the ink jet head has been increasing. In such an ink jet head, a driver IC for actuator control is directly mounted on the surface of the electrode glass substrate, and an input wiring for supplying an input signal for driving the driver IC is formed. Yes.

As such, “in an electrostatic actuator having a diaphragm and a counter electrode disposed to face each other with a gap therebetween, the counter electrode is opposed to the diaphragm in a hermetically sealed state. A counter electrode part, and a wiring part led out to the outside from a gap part that is hermetically sealed continuously to the counter electrode part. The counter electrode part is made of ITO, and the wiring part is made of a metal material. “A formed electrostatic actuator” has been proposed (for example, Patent Document 1).
reference).

Further, “a nozzle substrate in which a plurality of nozzle holes for discharging droplets are formed, a cavity substrate in which a bottom wall forms a vibration plate and a recess serving as a discharge chamber for storing the droplets; An electrode substrate on which an individual electrode for driving the diaphragm is formed facing the diaphragm, a recess serving as a common droplet chamber for supplying droplets to the discharge chamber, and the common droplet chamber to the discharge chamber A reservoir substrate having a through-hole for transferring a droplet, a nozzle communication hole for transferring a droplet from the discharge chamber to the nozzle hole, and a driver IC for supplying a drive signal to the individual electrode, The cavity substrate is provided with a first hole portion, the reservoir substrate is provided with a second hole portion, and the first hole portion and the second hole portion are communicated with each other to receive a container. The driver IC is a droplet accommodated in the accommodating portion. Out head "it has been proposed (e.g., see Patent Document 2).

JP 2001-253079 A JP 2006-224564 A

The electrostatic actuator described in Patent Document 1 aims to reduce the time constant of the actuator, and the counter electrode portion is formed of ITO (Indium Tin Oxide) and the wiring portion is formed of a metal material. As a result, an electrostatic actuator having no operation delay and excellent durability is realized. However, this electrostatic actuator does not have a structure in which a driver IC for actuator control is embedded in the ink jet head, and input wiring for supplying an input signal for driving the driver IC is not considered.

The droplet discharge head described in Patent Document 2 has a structure in which a driver IC for controlling an actuator is embedded in an inkjet head, so that nozzles can be arranged in multiple rows, and a droplet discharge head with a reduced size is realized. ing. However, since a plurality of nozzles can be driven at the same time, the time constant of the actuator drive circuit increases with an increase in the number of nozzles to be driven, and the actuator operation delay, that is, the droplet discharge operation delay is likely to occur. . In particular, the individual electrodes that make up the actuator and the drive signal from outside the driver I
This is likely to occur when the input wiring supplied to C is made of ITO.

The present invention has been made in order to solve the above-described problems. In a multi-nozzle droplet discharge head capable of simultaneously driving a plurality of nozzles, the time constant of the actuator drive circuit is reduced to reduce the droplets. It is an object of the present invention to provide a droplet discharge head, a droplet discharge device, a method for manufacturing a droplet discharge head, and a method for manufacturing a droplet discharge device in which a delay in discharge operation is reduced as much as possible.

A liquid droplet ejection head according to the present invention includes a nozzle substrate in which a plurality of nozzle holes for ejecting liquid droplets are formed, and a cavity in which a bottom wall forms a vibration plate and a pressure chamber for storing and ejecting liquid droplets is formed. A substrate, an individual electrode for driving the diaphragm facing the diaphragm with a gap, and an electrode substrate on which input wiring for taking in electric power for driving the diaphragm from the outside is formed;
The individual electrodes are formed of a conductive oxide, and a part of the input wiring has a stacked structure of a conductive oxide and a metal material.

In this way, by making a part of the input wiring a laminated structure of a conductive oxide and a metal material, it becomes possible to reduce the resistance of the wiring portion common to all nozzles, and the number of nozzles to be driven at the same time is increased. However, the time constant of the equivalent circuit can be reduced, the delay of the droplet discharge operation can be reduced, and the durability can be ensured because the individual electrodes are formed of a conductive oxide.
That is, the characteristics of the conductive oxide and the characteristics of the metal material can be combined.

The droplet discharge head according to the present invention is characterized in that a part of the conductive oxide constituting the input wiring is exposed. By configuring the input wiring in this way, the resistance of the input wiring is dominated by the metal material, and the resistance can be reduced.

In the droplet discharge head according to the present invention, a recess is formed in the electrode substrate, and at least a part of the input wiring having a laminated structure of a conductive oxide and a metal material is formed inside the recess,
It is characterized in that at least a part of the portion of the input wiring where the conductive oxide is exposed is formed outside the recess. Therefore, a part of the input wiring from which the conductive oxide is exposed comes directly on the electrode substrate, and an equipotential can be easily secured at the time of anodic bonding between the cavity substrate and the electrode substrate.

The droplet discharge head according to the present invention is characterized in that a part of the portion of the input wiring where the conductive oxide is exposed is brought into contact with the cavity substrate to form an equipotential contact. That is, the equipotential contact can be formed simultaneously with the formation of the input wiring without separately forming the equipotential contact, and the equipotential can be easily secured at the time of anodic bonding between the cavity substrate and the electrode substrate. it can.

In the droplet discharge head according to the present invention, the conductive oxide is made of ITO, IZO, GZO, AZO,
It is ATO, In ₂ O ₃ , ZnO, or SnO ₂ . Therefore, the durability of the input wiring and the individual electrode can be improved.

In the droplet discharge head according to the present invention, the metal material is Cr, Au, Ag, Cu, Ti, Al,
Or they are suitably combined and laminated. Since these metal materials have a characteristic that the resistance value is smaller than that of the conductive oxide, a reduction in resistance in the input wiring can be realized.

In addition, a droplet discharge device according to the present invention is equipped with the above-described droplet discharge head. Therefore, it has all the effects of the above-described droplet discharge head.

In the method for manufacturing a droplet discharge head according to the present invention, a concave portion for forming a part of an input wiring for taking in an electric power for driving an individual electrode and a diaphragm from the outside is formed on a glass substrate, Forming an electrode glass substrate by forming a conductive oxide that forms the individual electrodes and input wiring on a glass substrate, and forming a metal material on at least a part of the recess where the conductive oxide that forms the input wiring is formed Then, a silicon substrate is bonded to the electrode glass substrate, and a pressure chamber is formed in the silicon substrate to form a cavity substrate.

Therefore, the individual electrodes and the input wiring can be formed on the glass substrate without complicating the manufacturing process, and a part of the input wiring has a laminated structure of a conductive oxide and a metal material. It is possible to reduce the resistance of the common wiring section, and even if the number of nozzles to be driven at the same time is increased, the time constant of the equivalent circuit can be reduced, and the droplet discharge head that can reduce the delay of the droplet discharge operation Can be manufactured.

In the method for manufacturing a droplet discharge head according to the present invention, an insulating film is formed on a silicon substrate, an insulating film corresponding to a portion where the conductive oxide of the input wiring is exposed is removed, and a window portion is formed. An equipotential contact is ensured by bringing a conductive oxide and a silicon substrate into contact with each other through a window portion. Therefore, an equipotential contact can be easily formed, and an equipotential can be reliably ensured. In this way, the electric field disappears and discharge and field emission are prevented, so that a large current does not flow between the electrode on the electrode glass substrate side and the cavity substrate, and melting of the electrode is prevented. Can do.

The manufacturing method of the droplet discharge head according to the present invention is characterized in that after the silicon substrate and the electrode glass substrate are anodically bonded, the silicon substrate located in the vicinity of the equipotential contact is removed. In this way, each input wiring can be easily made independent.

A manufacturing method of a droplet discharge device according to the present invention includes the above-described manufacturing method of a droplet discharge head. Therefore, it has all the effects of the manufacturing method of the above-described droplet discharge head.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1.
FIG. 1 is an exploded perspective view showing a state in which the droplet discharge head 100 according to Embodiment 1 of the present invention is disassembled. FIG. 2 is a longitudinal sectional view showing a state in which the droplet discharge head 100 is assembled.
The AA 'cross section in FIG. 1 is shown. Based on FIG. 1 and FIG.
The configuration of 0 will be described. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

The droplet discharge head 100 is a face eject type liquid that discharges droplets from nozzle holes 5 provided on the surface side of the nozzle substrate 1 as a representative of electrostatic actuators driven by electrostatic force. 2 represents a droplet discharge head. FIG. 1 shows a driver IC 15 for supplying a drive signal to an individual electrode 17 described later, and an FPC (Flexible Printed Circuit) 3 for supplying an input signal to the driver IC 15.
A part of zero is shown.

As shown in FIG. 1, the droplet discharge head 100 is configured by sequentially stacking four substrates, an electrode glass substrate 4, a cavity substrate 3, a reservoir substrate 2, and a nozzle substrate 1. The nozzle substrate 1 is bonded to one surface of the reservoir substrate 2, and the cavity substrate 3 is bonded to the other surface of the reservoir substrate 2. An electrode glass substrate 4 is bonded to the opposite surface of the cavity substrate 3 to which the reservoir substrate 2 is bonded. That is, the electrode glass substrate 4, the cavity substrate 3, the reservoir substrate 2, and the nozzle substrate 1 are bonded in this order.

[Electrode glass substrate 4]
The electrode glass substrate 4 is preferably formed of glass such as borosilicate glass having a thickness of 1 mm as a main material. Here, a case where the electrode glass substrate 4 is formed of borosilicate glass is shown as an example, but the electrode glass substrate 4 may be formed of single crystal silicon, for example. A concave portion (glass groove) 12 is formed on the surface of the electrode glass substrate 4. Recess 1
The formation range of 2 will be described in detail with reference to FIG. The recess 12 is preferably formed to a depth of 0.3 μm (micrometer) by, for example, etching. Inside the recess 12 (especially at the bottom), the individual electrode 17 serving as a fixed electrode is opposed to a diaphragm 8 that forms a bottom surface of each pressure chamber 7 of the cavity substrate 3 to be described later with a certain interval. Have been made.

Further, the recess 12 is patterned in a slightly larger shape similar to these shapes so that a part of the recess 12 can be fitted with the individual electrode 17. This individual electrode 17 is, for example, ITO
(Indium Tin Oxide: indium tin oxide) can be sputtered to a thickness of 0.1 μm. When the thickness of the individual electrode 17 is 0.1 μm, the gap 18 formed between the individual electrode 17 and the diaphragm 8 after joining the electrode glass substrate 4 and the cavity substrate 3 is about 0.2 μm. It becomes. Thus, when the individual electrode 17 is made of ITO, since ITO is transparent, there is an advantage that it is easy to confirm whether or not the discharge has occurred.

Further, one end of the individual electrode 17 (the individual electrode lead portion 17a on the center side of the electrode glass substrate 4) is connected to the driver IC 15 so that a drive signal is supplied from the driver IC 15 to the individual electrode 17. It has become. The driver IC 15 includes an individual electrode 17
Are mounted in the concave portion 12 between the two electrode rows (intermediate portion of the concave portion 12 formed on the left and right sides of the electrode glass substrate 4 in order to produce the individual electrode 17), and are connected to both the left and right electrode rows. ing. Therefore, it becomes possible to supply drive signals from the driver IC 15 to the two electrode rows, and it is easy to increase the number of electrode rows. Further, since the number of installed driver ICs 15 is reduced, the cost can be reduced and the head can be miniaturized.

An FPC mounting portion 20 a for mounting the FPC 30 is formed on the electrode glass substrate 4. The FPC mounting portion 20a is formed as a part of the input wiring 20 for supplying an input signal for driving the driver IC 15 from the FPC 30, and the FPC 30 and the driver IC 15
And to connect. The input wiring 20 includes an FPC mounting part 20a, a lead part 20b extending the FPC mounting part 20a, and a driver IC input terminal mounting part 20c connected to an input terminal of the driver IC 15. From the viewpoint of reducing the circuit resistance, it is desirable that the input terminal of the driver IC 15 is directly connected to the input wiring 20 and the output terminal is directly connected to the end of the individual electrode 17.

The input wiring 20 is a wiring for taking in a driving signal (driving power) for driving the plurality of individual electrodes 17 from the outside of the electrode glass substrate 4. The input wiring 20 is formed by laminating a metal material or a plurality of metal materials, and has a structure in which the metal material is laminated on a part of ITO (FIG. 5). Explain in detail). Input wiring 2
The drive signal fetched from 0 is controlled by the driver IC 15 and the driver IC 1
5 is supplied as a pulse voltage to a predetermined individual electrode 17. That is, the electrode glass substrate 4
The input signal to the driver IC 15 from the outside is FPC 30 → FPC mounting portion 20a of input wiring 20 → lead portion 20b of input wiring 20 → driver IC input terminal mounting portion 2 of input wiring 20
0c → Driver IC15 is input.

The output signal from the driver IC 15 to which the drive signal is input is the driver I of the individual electrode 17.
C output terminal mounting portion → individual electrode lead portion 17a → applied to the individual electrode 17 corresponding to the nozzle hole 5 that is about to eject ink droplets. Then, the diaphragm 8 corresponding to the individual electrode 17 to which the output signal is applied is driven. By such a signal flow, the droplet discharge actuator formed by the individual electrode 17 and the diaphragm 8 corresponding thereto is driven.

Here, an equivalent circuit of the droplet discharge head 100 will be briefly described. Droplet discharge head 1
The time constant τ of the equivalent circuit of 00 can be obtained by τ = (C1 × n) × (R0 + R1 / n). In this equation, R0 represents a circuit common part resistance. That is, it represents the equivalent resistance of the resistance between the FPC mounting part 20a → the lead part 20b → the driver IC input terminal mounting part 20c. In particular, the overall equivalent resistance is greatly influenced by the resistance of the lead portion 20b.

R1 represents a circuit individual unit resistance. That is, the internal resistance of the driver IC 15 and the equivalent resistance of the resistance between the output terminal mounting portion → the individual electrode lead portion 17a → the individual electrode 17 of the individual electrode 17 are represented. C1 represents the capacitance of the electrostatic actuator. That is,
The electrostatic capacitance of the electrostatic actuator comprised with the individual electrode 17 and the diaphragm 8 is represented. n
Represents the number of drive actuators (the number of drive nozzles). Therefore, as expressed by the equation, the time constant τ can be expressed as a function of the number n of drive nozzles. As a result, when R0 is large, the time constant τ increases rapidly when the number of drive nozzles n is increased, that is, the operation delay increases.

This tendency is particularly remarkable when the input wiring 20 is made of ITO, whereas the input wiring 20 is made of a metal material (for example, chromium (Cr) or gold (Au)). If so, the increase in time constant τ is very small. As a result, if the input wiring 20 is made of a metal material, the increase in the time constant τ of the actuator drive circuit can be reduced even if the number n of simultaneously driven nozzles of the multi-nozzle head is increased, and the droplet discharge operation delay can be reduced. By avoiding this, the responsiveness can be improved. The configuration of the input wiring 20 will be described in detail with reference to FIG.

In addition, after joining the electrode glass substrate 4 and the cavity substrate 3, the sealing part 14 for sealing the gap 18 which is the predetermined space | gap formed between the electrode glass substrate 4 and the cavity substrate 3 is formed. Good. In the first embodiment, the case where two driver ICs 15 are mounted on the droplet discharge head 100 is shown as an example. However, the present invention is not limited to this. For example, the driver IC 15 may determine the number to be mounted according to the number of individual electrodes 17 to be driven.

When the laminated body is formed by joining the electrode glass substrate 4 and the cavity substrate 3, a certain gap (gap) between the diaphragm 8 and the individual electrode 17 can be deflected (displaced). ) 18 is formed by the recess 12 of the electrode glass substrate 4. The gap 18 is preferably formed to have a depth of 0.2 μm, for example. This gap 1
8 is determined by the depth of the recess 12 and the thickness of the individual electrode 17 and the diaphragm 8. Since the gap 18 greatly affects the discharge characteristics of the droplet discharge head 100, strict accuracy control is required. The diaphragm 8 is driven by an electrostatic force and functions as an actuator.

The gap 18 is formed at a position facing each diaphragm 8 so as to have an elongated constant depth. In addition to forming the recess 12 in the electrode glass substrate 4, the gap 18 can be provided by forming a recess in the silicon substrate to be the cavity substrate 3 or sandwiching a spacer. Further, the individual electrode 17 faces the diaphragm 8 with a gap of a constant interval, and extends to the end of the electrode glass substrate 4 along the bottom surface of the gap 18. At this end, the driver IC 15 is connected.

In the droplet discharge head 100, a plurality of individual electrodes 17 are formed in a rectangular shape having long sides and short sides, and the individual electrodes 17 are arranged so that their long sides are parallel to each other.
In FIG. 1, two electrode rows extending in the short side direction of the individual electrode 17 are shown. In addition,
When the short side of the individual electrode 17 is formed obliquely with respect to the long side, and the individual electrode 17 has an elongated parallelogram shape, an electrode array extending in a direction perpendicular to the long side direction is formed. do it. The electrode glass substrate 4 is provided with an ink supply hole 11a serving as a flow path for taking in liquid supplied from an external ink tank (not shown). This ink supply hole 11
a penetrates the electrode glass substrate 4.

Further, the depth of the recess 12, the length of the gap 18, and the thickness of the individual electrode 17 shown here are merely examples, and are not limited to the values shown here. Furthermore, although the case where the individual electrode 17 is made of ITO has been shown as an example, the present invention is not limited to this, and any conductive oxide may be used, for example, IZO (indium-added zinc oxide), GZO (gallium-added zinc oxide). ), AZO (aluminum-added zinc oxide), ATO (antimony-added tin oxide), In ₂ O ₃ (indium oxide), ZnO (zinc oxide), SnO ₂ (tin oxide), and the like.

[Cavity substrate 3]
The cavity substrate 3 is composed of, for example, a (110) plane silicon single crystal substrate (hereinafter simply referred to as a silicon substrate) having a thickness of about 50 μm as a main material. Either or both of dry etching and anisotropic wet etching are performed on the silicon substrate, and a plurality of pressure chambers (or discharge chambers) 7 whose bottom wall becomes the flexible vibration plate 8 are formed. The pressure chambers 7 are formed corresponding to the electrode rows of the individual electrodes 17 so that droplets such as ink are held and a discharge pressure is applied. The pressure chambers 7 are formed in parallel from the front side to the back side of the drawing. A through hole 24 that penetrates the cavity substrate 3 is formed in the middle portion of the cavity substrate 3.

Further, a TEOS film (here, Tetraethy) for electrically insulating the diaphragm 8 and the individual electrode 17 is formed on the lower surface of the cavity substrate 3 (the surface facing the electrode glass substrate 4).
l orthosilicate Tetraethoxysilane: An insulating film (not shown) which is a SiO ₂ film made of tetraethoxysilane (ethyl silicate)
Plasma CVD (Chemical Vapor Deposition: TEOS-
The film is formed to a thickness of about 0.1 μm using a method called pCVD. This is for preventing dielectric breakdown and short-circuit when the diaphragm 8 is driven, and for preventing etching of the cavity substrate 3 by droplets of ink or the like.

Although the case where the insulating film is a TEOS film is shown here, the present invention is not limited to this, and any material that improves the insulating performance may be used. For example, Al ₂ O ₃ (aluminum oxide (alumina)) may be used. Further, an SiO ₂ film (including a TEOS film) that is a liquid protective film (not shown) may be formed on the upper surface of the cavity substrate 3 by a plasma CVD method or a sputtering method. This is because, by forming the liquid protective film, it is possible to prevent the flow path from being corroded by the ink droplets. The stress of the liquid protective film and the stress of the insulating film are offset, and the diaphragm 8
There is also an effect of reducing the warpage of the.

The diaphragm 8 may be formed of a high concentration boron doped layer. The etching rate in etching single crystal silicon with an alkaline solution such as an aqueous potassium hydroxide solution is very small in a high concentration region of about 5 × 10 ¹⁹ atoms / cm ³ or more when the dopant is boron. For this reason, when the diaphragm 8 is made of a high-concentration boron-doped layer and the pressure chamber 7 is formed by anisotropic etching with an alkaline solution, the boron-doped layer is exposed and the etching rate becomes extremely small, so-called etching stop. By using the technique, the diaphragm 8 can be formed in a desired thickness.

The cavity substrate 3 is also provided with ink supply holes 11b (in communication with the ink supply holes 11a provided in the electrode glass substrate 4). Furthermore, a common electrode terminal 16 as an external electrode terminal is formed on the cavity substrate 3. The common electrode terminal 16 is connected to the FPC 30 and serves as a terminal for supplying charges having a polarity opposite to that of the individual electrode 17 to the diaphragm 8 from an external oscillation circuit (not shown) or the like.

[Reservoir substrate 2]
The reservoir substrate 2 is made of, for example, single crystal silicon as a main material, and two reservoirs 10 that are liquid storage chambers for supplying droplets such as ink to the pressure chambers 7 are formed on the left and right sides. This reservoir 10 is used in common for each row of pressure chambers 7. A supply port 9 for transferring droplets from the reservoir 10 to the pressure chamber 7 is formed through the bottom surface of the reservoir 10 in accordance with the position of each pressure chamber 7. In addition, an ink supply hole 11 c that penetrates the bottom surface of the reservoir 10 is formed on the bottom surface of the reservoir 10.

The ink supply hole 11c, the ink supply hole 11b formed in the cavity substrate 3, and the ink supply hole 11a formed in the electrode glass substrate 4 are joined to the reservoir substrate 2, the cavity substrate 3 and the electrode glass substrate 4. In this state, ink supply holes 11 are formed so as to communicate with each other, and droplets are supplied from an external ink tank. Furthermore, it becomes a flow path between each pressure chamber 7 and the nozzle hole 5 provided in the nozzle substrate 1.
A plurality of nozzle communication holes 6 serving as flow paths for transferring the ink droplets pressurized in step 1 to the nozzle holes 5 are formed in accordance with the nozzle holes 5. Note that a through hole 25 corresponding to the shape of the through hole 24 of the cavity substrate 3 is provided in an intermediate portion of the reservoir substrate 2 (between the reservoirs 10 formed on the left and right).
Is formed.

[Nozzle substrate 1]
The nozzle substrate 1 is made of, for example, a silicon substrate having a thickness of 100 μm as a main material, and a plurality of nozzle holes 5 communicating with the respective nozzle communication holes 6 are formed. Each nozzle hole 5 discharges the liquid droplets transferred from each nozzle communication hole 6 to the outside. In addition,
When the nozzle holes 5 are formed in a plurality of stages, it is possible to expect an improvement in straightness when discharging droplets. Here, the nozzle substrate 1 having the nozzle holes 5 is described as the upper surface, and the electrode glass substrate 4 is described as the lower surface. However, when actually used, the nozzle substrate 1 is lower than the electrode glass substrate 4. There are many.

When the electrode glass substrate 4, the cavity substrate 3, the reservoir substrate 2, and the nozzle substrate 1 are bonded, a substrate made of silicon and a substrate made of borosilicate glass are bonded (the electrode glass substrate 4 and the cavity substrate 3 Can be bonded by direct bonding when the substrates made of silicon are bonded to each other (when the cavity substrate 3 and the reservoir substrate 2 and the reservoir substrate 2 and the nozzle substrate 1 are bonded). . Further, the substrates made of silicon can be bonded using an adhesive.

As shown in FIG. 2, in this droplet discharge head 100, a driver IC 15 is embedded (contained) inside the droplet discharge head 100, the nozzle substrate 1 on the top surface, the reservoir substrate 2 and the cavity substrate 3 on the side surface. The lower surface is closed by the electrode glass substrate 4. That is, the housing portion 26 is formed by the through hole 24 of the cavity substrate 3 and the through hole 25 of the reservoir substrate 2, and the driver IC 15 is housed in the housing portion 26. In addition, it is desirable that the housing portion 26 be hermetically sealed to protect the driver IC 15 from droplets and outside air.

Further, a gap 18 formed when the electrode glass substrate 4 and the cavity substrate 3 are joined.
In order to hermetically seal the sealing portion 14 is formed on the through hole 24 side. By doing so, the gap 18 can be hermetically sealed. Note that the material used for the sealing portion 14 is not particularly limited, and any material that can hermetically seal the gap 18 may be used. For example,
The sealing portion 14 may be formed of silicon oxide (SiO ₂ ) having low moisture permeability, aluminum oxide (Al ₂ O ₃ ), silicon oxynitride (SiON), silicon nitride (SiN), polyparaxylylene, or the like.

Here, the operation of the droplet discharge head 100 will be described. A droplet such as ink is supplied to the reservoir 10 from the outside through the ink supply hole 11. In addition, droplets are supplied to the pressure chamber 7 from the reservoir 10 through the supply port 9. The driver IC 15 includes an FPC 3
Drive signal (pulse voltage) from a control unit (not shown) of the droplet discharge device via the 0 input wiring 20
Is supplied. The individual electrode 17 selected by the driver IC 15 has 0V.
A pulse voltage of about ˜40 V is applied to charge the individual electrode 17 positively.

At this time, a charge having a negative polarity is supplied from an external oscillation circuit or the like to the diaphragm 8 of the corresponding cavity substrate 3 via the common electrode terminal 16, and the diaphragm corresponding to the positively charged individual electrode 17. 8 is relatively negatively charged. Therefore, an electrostatic force is generated between the selected individual electrode 17 and the diaphragm 8. When an electrostatic force is generated between the individual electrode 17 and the diaphragm 8, the diaphragm 8 is drawn toward the individual electrode 17 side by the electrostatic force and bends. This increases the volume of the pressure chamber 7.

Next, when the supply of the pulse voltage to the individual electrode 17 is stopped, the electrostatic force between the diaphragm 8 and the individual electrode 17 disappears, and the diaphragm 8 is restored to the original state. At this time, the pressure inside the pressure chamber 7 rises rapidly, and the droplets in the pressure chamber 7 pass through the nozzle communication hole 6 and are discharged from the nozzle hole 5. Printing or the like is performed by the droplets landing on a recording sheet, for example. Thereafter, the droplets are replenished from the reservoir 10 into the pressure chamber 7 through the supply port 9, and the initial state is restored. Such a method is called pulling, but there is also a method called pushing that discharges droplets using a spring or the like.

The supply of droplets to the reservoir 10 of the droplet discharge head 100 is performed by, for example, a droplet supply tube (not shown) connected to the ink supply hole 11. In addition, FPC30 is FP
The driver IC 15 is connected so that the longitudinal direction of C30 is parallel to the short side direction of the individual electrode 17 forming the electrode array. For example, when the short side of the individual electrode 17 is inclined with respect to the long side and the individual electrode 17 has an elongated parallelogram shape, the FPC 30 is connected in a direction perpendicular to the long side of the individual electrode 17. That's fine. Thereby, the droplet discharge head 100 having a plurality of electrode rows and the FPC 30 can be connected in a compact manner.

FIG. 3 is a schematic block diagram showing a control system of a droplet discharge device on which the droplet discharge head 100 is mounted. The case where the droplet discharge device is a general ink jet printer will be described as an example. Based on FIG. 3, the control system of the droplet discharge device on which the droplet discharge head 100 is mounted will be described. However, the control system of the droplet discharge device on which the droplet discharge head 100 is mounted is not limited to the control system shown in FIG.

The ink jet printer includes a drive control device 41 for driving and controlling the droplet discharge head 100. The drive control device 41 includes a control unit 42 configured around a CPU (central processing unit) 42a. The CPU 42a receives print information from an external device 43 such as a personal computer or a remote control device (remote control). This print information is input via the bus 43a or input by a wireless signal such as an infrared signal. In addition, the CPU 42a is connected to the ROM 44a through the internal bus 42b.
A RAM 44b and a character generator 44c are connected.

The control unit 42 uses the storage area in the RAM 44b as a work area, executes a control program stored in the ROM 44a, and drives the droplet discharge head 100 based on character information generated from the character generator 44c. Control signal is generated.
The control signal becomes a drive control signal corresponding to the print information via the theoretical gate array 45 and the drive pulse generation circuit 46, and is supplied to the driver IC 15 built in the droplet discharge head 100 via the connector 47. In addition, it is supplied to the COM generation circuit 46a. The driver IC 15 also has a drive pulse signal V3 for printing, a control signal LP, and a polarity inversion control signal RE.
V and the like (see FIG. 4) are also supplied. The COM generation circuit 46a may be constituted by a common electrode IC (not shown) for generating a drive pulse, for example.

In the COM generation circuit 46a, the droplet discharge head 100 is based on the supplied signals.
The common electrode terminal 16, that is, a drive signal (drive voltage pulse) to be applied to each diaphragm 8 is output from a common output terminal COM (not shown). Driver IC1
5, based on the supplied signals and the drive voltage Vp supplied from the power supply circuit 70, drive signals (drive voltage pulses) to be applied to the individual electrodes 17 are supplied in the number corresponding to the individual electrodes 17. The output is made from the individual output terminal SEG. And common output terminal CO
A potential difference between the output of M and the output of the individual output terminal SEG is applied between each diaphragm 8 and the individual electrode 17 facing it. When the diaphragm 8 is driven (when droplets are ejected), a drive potential difference waveform in the designated direction is given, and when the diaphragm 8 is not driven, no drive potential difference is given.

FIG. 4 is a schematic block diagram showing an example of the internal configuration of the driver IC 15 and the COM generation circuit 46a. It is assumed that the driver IC 15 and the COM generation circuit 46a shown in FIG. 4 supply drive signals to the 64 individual electrodes 17 and the diaphragm 8 in one set. Driver I
An example is shown in which C15 is a high-voltage driver with a 64-bit output of CMOS that operates by being supplied with the high-voltage drive voltage Vp and the logic-circuit drive voltage Vcc from the power supply circuit 70.

The driver IC 15 applies one of the drive voltage pulse and the GND potential to the individual electrode 17 in accordance with the supplied drive control signal. The driver IC 15 has a 64-bit shift register 61. The shift register 61 is a basic clock pulse that synchronizes the DI signal input of 64-bit length transmitted from the theoretical gate array 45 as serial data with the DI signal.
This is a static shift register that shifts up data by inputting an SCL pulse signal and stores it in a register in the shift register 61. The DI signal has 64 individual electrodes 17.
Is a control signal indicating selection information for selecting each of them by ON / OFF, and this signal is transmitted as serial data.

The driver IC 15 has a 64-bit latch circuit 62. The latch circuit 62 stores the data by latching the 64-bit data stored in the shift register 61 with a control signal (latch pulse) LP. This is a static clutch that outputs the data to the 64-bit inversion circuit 63 as a signal. In the latch circuit 62, the DI signal of the serial data is converted into a 64-bit parallel signal for outputting 64 segments for driving each diaphragm 8.

The bit inverting circuit 63 outputs an exclusive OR of the signal input from the latch circuit 62 and the REV signal to the level shifter 64. The level shifter 64 is a level interface circuit that converts the voltage level of the signal from the bit inverting circuit 63 from a logic system voltage level (5 V level or 3.3 V level) to a head drive system voltage level (0 to 45 V level). . The SEG driver 65 is a 64 channel transmission gate output. By the input of the level shifter 64, the segment outputs of SEG1 to SEG64 are
Either drive voltage pulse input or GND input is output. The COM driver 66 built in the COM generation circuit 46a outputs either a drive voltage pulse or a GND input to the COM in response to the REV input.

The XSCL, DI, LP, and REV signals are logic voltage level signals,
This signal is transmitted from the theoretical gate array 45 to the driver IC 15. Thus, by configuring the driver IC 15 and the COM generation circuit 46a, the number of segments to be driven (
Even when the number of diaphragms 8) increases, it is possible to easily switch between the driving voltage pulse and GND for driving the diaphragm 8 of the droplet discharge head 100. Each signal above is
It is supplied to the driver IC 15 through the input wiring 20 formed on the electrode glass substrate 4.

FIG. 5 is an explanatory diagram for explaining the input wiring 20 in detail. Based on FIG. 5, the configuration of the input wiring 20, which is a feature of the first embodiment, will be described in detail. In addition, FIG.
5A is an enlarged plan view showing the state of the input wiring 20 as viewed from above, FIG. 5B is a longitudinal sectional view showing a CC section in FIG. 5A, and FIG. The longitudinal cross-sectional view which shows the DD cross section in (a) is shown, and FIG.5 (d) has each shown the longitudinal cross-sectional view which shows the EE cross section in Fig.5 (a). FIG. 5 is an enlarged view of the portion X shown in FIG.

As shown in FIG. 5, a plurality of input wirings 20 are formed on the electrode glass substrate 4. Each of the input wirings 20 corresponds to each of the above signals, and is formed by the number of signals supplied to the driver IC 15. The electrode glass substrate 4 has an input wiring 2
A recess 12 that is a glass groove for forming 0 is formed.
As shown to (a), it is not formed to the edge part by the side of the FPC mounting part 20a of the electrode glass substrate 4. FIG. A part of the input wiring 20 has a laminated structure of a metal material (metal film 82) and ITO (ITO film 81). Although the thickness of this metal material is not particularly limited, it may be formed, for example, with a thickness of about 0.1 to 0.5 μm.

Considering the manufacturing process, it is easier to form the input wiring 20 simultaneously with ITO when forming the individual electrodes 17 made of ITO. However, since ITO has a large resistance value, when a large number of nozzles are driven simultaneously, there is a problem that the time constant (τ) of the corresponding actuator increases and the responsiveness deteriorates. As described above, when the input wiring 20 is formed of a metal material, the increase in the time constant τ is extremely small, and even if the number n of simultaneously driven nozzles of the multi-nozzle head is increased, the response of the droplet discharge operation is avoided. Can be better. That is, when the input wiring 20 is made of a metal material, the wiring resistance of the metal material becomes dominant and the wiring resistance can be lowered.

However, if the entire input wiring 20 is made of a metal material, the equipotential contact 33 is made of the metal material.
(Refer to FIG. 6) will be formed, and alteration due to discharge and failure due to migration will occur. In that respect, since ITO is a conductive oxide, it is characterized in that it does not cause deterioration due to discharge, failure due to migration, or the like. Therefore, in the first embodiment, a combination of the characteristic that the resistance value of the metal material is small and the characteristic that it is a conductive oxide of ITO makes a part of the input wiring 20 a laminated structure of the metal material and ITO. It is.

As shown in FIG. 5D, the input wiring 20 is configured by forming an ITO film 81 on the lower side and forming a metal film 82 on a part of the ITO. That is, the input wiring 20 has a portion where the metal film 82 is a surface layer ((a) shown in FIG. 5A) and a portion where the ITO film 81 is a surface layer (shown in FIG. 5A). A)) exists. The input wiring 20 corresponding to the portion where the recess 12 is formed has a laminated structure of the ITO film 81 and the metal film 82 (FIG. 5B), and corresponds to the portion where the recess 12 is not formed. Input wiring 20 is IT
The O film 81 has a single-layer structure (FIG. 5C).

That is, the portion of the input wiring 20 on which the ITO film 81 is the surface layer is directly on the electrode glass substrate 4 (FIGS. 5C and 5D). The ITO film 81 mounted on the electrode glass substrate 4 comes into contact with the cavity substrate 3 to form the equipotential contact 33. The electrode glass substrate 4 formed in this manner is bonded to the cavity substrate 3 at the bonding interface 31 shown in FIG. 5B and the bonding interface 32 shown in FIG. The insulating film 23 is removed from the portion of the cavity substrate 3 corresponding to the equipotential contact 33 (described in detail in FIG. 6).

Since a part of the input wiring 20 has a laminated structure of a metal material and ITO, the wiring resistance common to all nozzles can be reduced, and the time constant (τ) of the equivalent circuit can be reduced even if the number of simultaneously driven nozzles increases. Can be small. Thereby, since the operation delay is reduced, it is possible to manufacture the droplet discharge head 100 having a discharge performance with excellent responsiveness without requiring a complicated manufacturing process. Further, since ITO is used for the individual electrode 17, it is possible to ensure durability.
In addition, in FIG. 5, although ITO was demonstrated to the example, it is not limited to this, Materials other than ITO may be used as long as it is the conductive oxide mentioned above.

The metal material only needs to have a low resistance. For example, Cr, Au, Ag (silver)
Cu (copper), Ti (titanium), Al (aluminum), and a combination thereof can be used by being laminated. These metal materials have a characteristic that the resistance value is smaller than that of ITO. Therefore, such a metal material is laminated on ITO to input wiring 2
By forming 0, even when a large number of actuators are driven simultaneously, it is possible to reduce the response delay of the operation.

FIG. 6 is an explanatory diagram for explaining the equipotential contact 33. The equipotential contact 33 will be described with reference to FIG. 6A is a cross-sectional view taken along the line CC in FIG. 5A in a state where the electrode glass substrate 4 and the cavity substrate 3 are bonded, and FIG. 6B is a bond between the electrode glass substrate 4 and the cavity substrate 3. The DD cross section in Fig.5 (a) of the made state is each shown. FIG.
As shown to (a), the insulating film 23 is formed in the cavity board | substrate 3 corresponding to the part from which the metal film 82 of the input wiring 20 becomes a surface layer.

On the other hand, as shown in FIG. 6B, a window portion 34 from which the insulating film 23 has been removed is formed in the cavity substrate 3 corresponding to the portion where the ITO film 81 of the input wiring 20 is the surface layer. . The concave portion 12 is not formed in the portion where the ITO film 81 of the input wiring 20 is a surface layer, and the ITO film 81 runs directly on the electrode glass substrate 4, that is, the projection is higher than the upper surface of the electrode glass substrate 4. An equipotential contact 33 is formed so as to rise. IT
The equipotential contact 33 is formed of O. This equipotential contact 33 is used for anodic bonding.
This is for ensuring the equipotential state by bringing the electrode portion of the electrode glass substrate 4 and the cavity substrate 3 into contact with each other.

As shown in FIG. 6B, when the equipotential between the electrode portion of the electrode glass substrate 4 and the cavity substrate 3 is taken through a slight gap, if the ITO is the equipotential contact 33, the ITO
Since is a conductive oxide, no deterioration due to discharge or failure due to migration occurs. On the other hand, when the equipotential contact 33 is formed of a metal material, damage due to discharge or the like also affects the cavity substrate 3, and the droplet discharge head 100 with a low degree of completion is formed. For this reason, the equipotential contact 33 is preferably formed of ITO. In addition, ITO has a crystalline protrusion on the surface of several tens of nanometers, and it is preferable that the equipotential contact 33 is formed of ITO because it has a structure that facilitates discharge through the protrusion.

Next, the manufacturing process of the droplet discharge head 100 will be described. FIG. 7 shows the first embodiment.
It is BB sectional drawing (refer FIG. 1) which shows an example of the manufacturing process of the electrode glass substrate 4 which is a characteristic part. Based on FIG. 7, the manufacturing process of the electrode glass substrate 4 which forms the recessed part 12 of predetermined depth according to the shape pattern of the individual electrode 17 and the input wiring 20 is demonstrated. In practice, a plurality of droplet discharge head members are generally formed simultaneously from a silicon wafer, but only a part of them is shown in a simplified manner in FIG. Moreover, although an example of the manufacturing process of the electrode glass board | substrate 4 is shown here, it is not limited to this.

First, a borosilicate glass substrate 4 ′ processed to a predetermined thickness (for example, 1 mm thick).
Is prepared (FIG. 7A). Next, an etching mask 80 made of, for example, chromium (Cr) is formed on the upper surface (bonding surface with the cavity substrate 3) of the glass substrate 4 ′ by a sputtering apparatus. Then, a resist (not shown) is applied to the surface of the etching mask 80, and resist patterning for forming the recess 12 which is a glass groove is performed by photolithography (stepper, mask aligner, etc.). At this time, the etching mask 80 is patterned so that the end portion on the FPC mounting portion 20a side is not etched. Then, the etching mask 80 is etched and patterned (FIG. 7B).

Next, the glass substrate 4 ′ is dipped in, for example, an aqueous ammonium fluoride solution and etched to form a recess 12 having a predetermined depth (FIG. 7C). Then, after the resist is stripped with an organic stripper or the like, the glass substrate 4 ′ is dipped in a chrome etchant to remove the etching mask 80 (FIG. 7).
(D)). In this way, the recess 12 can be formed. In addition, what is necessary is just to repeat the said process, when making the recessed part 12 into a several level | step difference structure. If it does so, the recessed part 12 formed in glass substrate 4 'can be easily made into a several level | step difference structure.

After the formation of the recess 12, for example, an ITO film 81 is formed on the entire patterning surface of the glass substrate 4 ′ on which the recess 12 is formed and on the surface (the surface on which the recess 12 is not formed) that becomes the FPC mounting portion 20 a
Is deposited by a sputtering apparatus to a thickness of about 0.1 μm (FIG. 7E). Then, a resist (not shown) is patterned and etched by photolithography to form an ITO pattern corresponding to the individual electrode 17 and the input wiring 20 (FIG. 7F). Here, a case where the material of the individual electrode 17 and the input wiring 20 is ITO has been described as an example, but other materials may be used as described above.

Then, a metal film 82 made of a metal material is formed on a part of the upper surface of the ITO film 81 to be the input wiring 20.
Is formed (FIG. 7G). A plan view of this state as seen from above is shown in FIG. As described above, a part of the input wiring 20 is formed as a laminated structure of the ITO film 81 and the metal film 82. The metal film 82 can be formed by, for example, a sputtering apparatus. The metal material constituting the metal film 82 is not particularly limited, and the metal film 82 may be made of the metal material as described above. As described above, the glass substrate 4 ′ is processed to produce the electrode glass substrate 4.

Thereafter, as shown in FIG. 6, the cavity substrate 3 having the window 34 formed thereon is anodically bonded to the electrode glass substrate 4. By contacting the cavity substrate 3 and the ITO film 81 through the window 34 (that is, forming the equipotential contact 33), the equipotential between the individual electrode 17 and the cavity substrate 3 is ensured at the time of anodic bonding. Can be secured. That is, the equipotential contact 33 is formed by forming a part of the ITO film 81 directly on the electrode glass substrate 4.
There is an advantage that can be formed simultaneously.

FIG. 8 is a cross-sectional view showing a part of the manufacturing process after anodic bonding of the cavity substrate 3 and the electrode glass substrate 4. A processing example after anodic bonding of the cavity substrate 3 and the electrode glass substrate 4 will be described with reference to FIG. FIG. 8A shows a CC sectional view and a DD sectional view (see FIG. 5A) in a state immediately after the cavity substrate 3 and the electrode glass substrate 4 are anodically bonded, and FIG. ) Causes the cavity substrate 3 and the electrode glass substrate 4 to be anodically bonded, and the FPC mounting portion 20
The CC sectional view and DD sectional view (refer to Drawing 5 (a)) in the state where a was formed are shown, respectively.

After the cavity substrate 3 and the electrode glass substrate 4 are anodically bonded, the cavity substrate 3 is subjected to K
OH etching is performed to form the pressure chamber 7, the diaphragm 8, the through hole 24, and the FPC mounting portion 20a. At this time, as shown in FIG. 8A, the portion that becomes the FPC mounting portion 20a is the diaphragm 8.
Thinner slightly thicker. Then, dry etching (for example, RIE (Reac
The insulating film 23 and the cavity substrate 3 are removed by a method such as “Tive Ion Etching”), and the input wiring 20 corresponding to the FPC mounting portion 20a is exposed.

At this time, each input wiring 20 is electrically independent. Therefore, by removing a part on the cavity substrate 3 side after the anodic bonding, independence of each input wiring 20 can be easily realized. Thereafter, the reservoir substrate 2 is bonded to the cavity substrate 3 and the nozzle substrate 1 is bonded to the reservoir substrate 2 using an adhesive such as an epoxy resin, whereby the droplet discharge head 100 is manufactured. Further, since the equipotential contact 33 is formed by the ITO film 81 directly on the electrode glass substrate 4, the electric field disappears and discharge and field emission are prevented, and the electrodes (input wiring 20 and individual electrodes) on the electrode glass substrate 4 side are prevented. 17) and a large current can be prevented from flowing through the cavity substrate 3, and the melting of the electrode on the electrode glass substrate 4 side can be prevented.

Embodiment 2. FIG.
FIG. 9 is a perspective view showing an example of a droplet discharge device 150 equipped with the droplet discharge head 100 described above. A droplet discharge device 150 shown in FIG. 9 is a general inkjet printer. The droplet discharge device 150 can be manufactured by a known manufacturing method.
The droplet discharge head 100 described above forms the recess 12 of the electrode glass substrate 4 in a predetermined range,
This is characterized in that a part of the conductive oxide constituting the input wiring 20 is directly laid on the electrode glass substrate 4.

In addition to the droplet discharge device 150 shown in FIG. 9, the droplet discharge head 100 changes the droplets in various ways, thereby manufacturing a color filter for a liquid crystal display, forming a light emitting portion of an organic EL display device, The present invention can also be applied to liquid discharge. In addition, the droplet discharge head 100 is
It can also be used for a piezoelectric drive type droplet discharge device and a bubble jet (registered trademark) type droplet discharge device. For example, in a case where the droplet discharge head 100 is used as a dispenser and is used for discharging onto a substrate that is a microarray of biomolecules, DNA (Deoxyribo Nuc) is used.
leic Acids: deoxyribonucleic acid), other nucleic acids (eg Ribo Nucle)
(ic Acid: Ribonucleic acid, Peptide Nucleic Acids: Peptide nucleic acid, etc.) A liquid containing a probe such as a protein may be discharged.

Note that the droplet discharge head, the droplet discharge device, the method for manufacturing the droplet discharge head, and the method for manufacturing the droplet discharge device according to the embodiment of the present invention are limited to the contents described in the above embodiments. It can be modified within the scope of the idea of the present invention. Further, the droplet discharge head 100 has been described as an example of a four-layer structure including the electrode glass substrate 4, the cavity substrate 3, the reservoir substrate 2, and the nozzle substrate 1. However, the present invention is not limited to this, and the driver IC 15 is included in the head. Any structure can be applied.

FIG. 3 is an exploded perspective view illustrating a state in which the droplet discharge head according to Embodiment 1 is disassembled. It is A-A 'sectional view in the state where a droplet discharge head was assembled. It is a schematic block diagram which shows the control system of the droplet discharge apparatus by which a droplet discharge head is mounted. It is a schematic block diagram which shows an example of an internal structure of a driver IC and a COM generation circuit. It is explanatory drawing for demonstrating an input wiring in detail. It is explanatory drawing for demonstrating an equipotential contact. It is BB sectional drawing which shows an example of the manufacturing process of the electrode glass substrate which is the characteristic part of Embodiment 1. FIG. It is sectional drawing which shows a part of manufacturing process after anodic bonding of a cavity substrate and an electrode glass substrate. It is the perspective view which showed an example of the droplet discharge apparatus carrying a droplet discharge head.

Explanation of symbols

1 nozzle substrate, 2 reservoir substrate, 3 cavity substrate, 4 electrode glass substrate, 4 '
Glass substrate, 5 nozzle hole, 6 nozzle communication hole, 7 pressure chamber, 8 diaphragm, 9 supply port, 10 reservoir, 11 ink supply hole, 11a ink supply hole, 11b ink supply hole, 11c ink supply hole, 12 recess, 14 sealing part, 15 driver IC, 16 common electrode terminal, 17 individual electrode, 17a individual electrode lead part, 18 gap, 20 input wiring, 20a mounting part, 20b lead part, 20c input terminal mounting part, 23 insulating film, 24
Through hole, 25 Through hole, 26 Housing, 30 FPC, 31 Bonding interface, 32 Bonding interface, 33 Equipotential contact, 34 Window, 41 Drive control device, 42 Control unit, 42a CP
U, 42b Internal bus, 43 External device, 43a bus, 44a ROM, 44b RA
M, 44c Character generator, 45 theoretical gate array, 46 drive pulse generation circuit, 46a COM generation circuit, 47 connector, 61 shift register, 62 latch circuit, 63 bit inversion circuit, 64 level shifter, 65 SEG driver, 66 CO
M driver, 70 power supply circuit, 80 etching mask, 81 ITO film, 82 metal film, 100 droplet ejection head, 150 droplet ejection apparatus.

Claims (11)

A nozzle substrate having a plurality of nozzle holes for discharging droplets;
A cavity substrate in which a bottom wall forms a diaphragm, and a pressure chamber is formed for collecting and discharging the droplets;
An individual electrode for driving the diaphragm facing the diaphragm with a gap, and an electrode substrate on which input wiring for taking in electric power for driving the diaphragm from the outside is formed;
The droplet discharge head, wherein the individual electrode is formed of a conductive oxide, and a part of the input wiring has a laminated structure of the conductive oxide and a metal material. The droplet discharge head according to claim 1, wherein a part of the conductive oxide constituting the input wiring is exposed. Forming a recess in the electrode substrate;
At least a part of the input wiring having a laminated structure of the conductive oxide and the metal material is formed inside the recess, and at least a portion of the input wiring where the conductive oxide is exposed The droplet discharge head according to claim 2, wherein a part of the droplet discharge head is formed outside the recess. 4. The droplet discharge head according to claim 2, wherein a part of the input wiring where the conductive oxide is exposed is brought into contact with the cavity substrate to form an equipotential contact. The conductive oxide is
ITO, IZO, GZO, AZO, ATO, In 2 O 3, ZnO, or a droplet discharge head according to claim 1, characterized in that the SnO _2. The metal material is
The droplet discharge head according to any one of claims 1 to 5, wherein Cr, Au, Ag, Cu, Ti, Al, or a combination of them is appropriately laminated. A liquid droplet ejection apparatus comprising the liquid droplet ejection head according to claim 1. In the glass substrate, a recess for forming a part of the input wiring for taking in the electric power for driving the individual electrode and the diaphragm from the outside,
Forming a conductive oxide constituting the individual electrodes and the input wiring on the glass substrate,
Forming an electrode glass substrate by forming a metal material in at least a part of the concave portion in which the conductive oxide to be the input wiring is formed,
Bonding a silicon substrate to the electrode glass substrate,
A method of manufacturing a droplet discharge head, wherein a pressure chamber is formed in the silicon substrate to form a cavity substrate. Forming an insulating film on the silicon substrate;
Removing the insulating film corresponding to the exposed portion of the conductive oxide of the input wiring to form a window,
The method of manufacturing a droplet discharge head according to claim 8, wherein an equipotential contact is ensured by bringing the conductive oxide and the silicon substrate into contact with each other through the window. After anodically bonding the silicon substrate and the electrode glass substrate,
The method for manufacturing a droplet discharge head according to claim 9, wherein the silicon substrate located in the vicinity of the equipotential contact is removed. A method for manufacturing a droplet discharge device, comprising the method for manufacturing a droplet discharge head according to any one of claims 8 to 10.

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