JP4696781B2 - Method for manufacturing droplet discharge head and method for manufacturing droplet discharge device - Google Patents

Description

  The present invention relates to a method of manufacturing a droplet discharge head and a method of manufacturing a droplet discharge device, and more particularly to a method of manufacturing a droplet discharge head and a method of manufacturing a droplet discharge device that reliably bond a nozzle substrate and a reservoir substrate.

  In recent years, ink jet heads having a structure having a plurality of nozzle arrays have been required for the purpose of high-speed printing of high-resolution images and multi-coloring. In order to realize this requirement, it is necessary to increase the nozzle density of the inkjet head and lengthen it (increase the number of nozzles per row). Along with this, the number of actuators in the ink jet head is also increasing. Under such circumstances, various small-sized inkjet heads having long and multi-row nozzle rows with a high nozzle density have been proposed.

  Among such ink jet heads, there is one in which a driver IC for supplying driving power to individual electrodes is installed in the ink jet head. In such an ink jet head, a driver IC is generally mounted on an electrode mounting portion (bump) with an anisotropic conductive adhesive. The anisotropic conductive adhesive contains conductive particles, and electrical connection between the driver IC and the electrode mounting portion is realized through the conductive particles.

  For example, “An IC chip for control is mounted face down on the surface of a substrate on which an electrothermal conversion element as an energy generating element and an ink flow path and an ink discharge port are formed, and the input side of the IC chip is a flexible printed circuit board. A liquid ejecting head that is connected to an external extraction electrode ”is disclosed (see, for example, Patent Document 1). This liquid ejecting head is characterized in that the control IC component is mounted on the element substrate by a resin layer in which conductive particles are dispersed in an insulating resin.

JP 2002-210969 (page 5 and FIG. 1)

  The liquid ejecting head has a problem in that the IC chip surface forms a part of the nozzle surface, so that a layer protecting the ink from the ink is required on the IC chip surface and the structure becomes complicated. In addition, since the position of the IC chip is closer to the printing paper than the nozzle, the flying distance of the ink droplets cannot be shortened, and the landing of the ink droplets is liable to occur, making high-definition printing difficult. There was also a problem. Furthermore, since the ink flow path and the FPC are arranged on opposite sides of the IC chip, there is a problem that when the number of nozzle rows is increased, the entire liquid ejecting head becomes larger. there were.

  In order to solve the above problems, a liquid droplet ejection head having a structure in which an IC chip is accommodated in each substrate (electrode substrate, cavity substrate, reservoir substrate, nozzle substrate) constituting the liquid ejecting head is provided. Conceivable. However, when the IC chip is mounted after the adhesive substrate and the reservoir substrate are bonded to each other and the electrode substrate and the cavity substrate are bonded, the gas released from the binder in the anisotropic conductive adhesive adheres to the reservoir substrate. A new problem has occurred that the adhesive bonding strength between the substrate and the nozzle substrate is reduced.

  In general, in order to increase the adhesive bonding strength between the reservoir substrate and the nozzle substrate, a primer layer serving as a base is often formed on the reservoir substrate and the nozzle substrate. However, when the reservoir substrate and the nozzle substrate are adhesively bonded using an epoxy adhesive, if the released gas from the binder in the anisotropic conductive adhesive adheres to the reservoir substrate, the released gas becomes a foreign substance and adhesively bonds. Strength will fall. Another possible method is to remove the released gas adhering to the reservoir substrate. However, since the primer layer has already been formed on the reservoir substrate, the primer layer is also removed when attempting to remove the attached released gas. Will be. Furthermore, it is technically difficult to form the primer layer again after removing the primer layer once.

  The present invention relates to a method for manufacturing a droplet discharge head and a droplet discharge device for securely bonding a reservoir substrate and a nozzle substrate so that a gas released from a binder in an anisotropic conductive adhesive does not adhere to the reservoir substrate. An object is to provide a manufacturing method.

The manufacturing method of a droplet discharge head according to the present invention includes an electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a driving signal to the individual electrode are formed, and a portion corresponding to the mounting portion. A cavity substrate in which a first hole portion opened and a pressure chamber for droplet discharge are formed at positions facing the individual electrodes, and a second hole portion and pressure that are open to communicate with the first hole portion A step of forming a laminate in which a reservoir substrate on which a reservoir for supplying droplets to the chamber is formed is laminated, and a mask in which a portion corresponding to the second hole is opened is a reservoir substrate of the laminate And a step of mounting the driver IC on the mounting portion of the laminate by an anisotropic conductive adhesive after the mask is set.

According to the above configuration in which the driver IC is mounted after the mask is set on the reservoir substrate of the stacked body, the gas released when the driver IC is mounted does not adhere to the reservoir substrate. That is, since gas does not adhere to the reservoir substrate, the adhesive bonding strength between the reservoir substrate and the nozzle substrate does not decrease. Therefore, the reservoir substrate and the nozzle substrate can be reliably bonded. In addition, since the reservoir substrate and the nozzle substrate can be securely bonded to each other, it is possible to provide a manufacturing method with a high yield.
In addition, since the driver IC and the individual electrode are mounted with an anisotropic conductive adhesive, the driver IC and the individual electrode can be electrically connected. This anisotropic conductive adhesive is obtained by dispersing conductive particles in a thermosetting resin.

The manufacturing method of a droplet discharge head according to the present invention includes an electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a driving signal to the individual electrode are formed, and a portion corresponding to the mounting portion. A cavity substrate in which a first hole portion opened and a pressure chamber for droplet discharge are formed at positions facing the individual electrodes, and a second hole portion and pressure that are open to communicate with the first hole portion Forming a laminate in which a reservoir substrate on which a reservoir for supplying droplets to the chamber is formed is laminated, and attaching a protective tape to a portion of the laminate substrate other than the second hole portion And a step of mounting the driver IC on the mounting portion of the laminated body with an anisotropic conductive adhesive after applying the protective tape.

According to the above configuration in which the driver IC is mounted after the protective tape is attached on the reservoir substrate of the laminate, the gas released when the driver IC is mounted does not adhere to the reservoir substrate. That is, since gas does not adhere to the reservoir substrate, the adhesive bonding strength between the reservoir substrate and the nozzle substrate does not decrease. Therefore, the reservoir substrate and the nozzle substrate can be reliably bonded. In addition, since the reservoir substrate and the nozzle substrate can be securely bonded to each other, it is possible to provide a manufacturing method with a high yield.
In addition, since the driver IC and the individual electrode are mounted with an anisotropic conductive adhesive, the driver IC and the individual electrode can be electrically connected.

The manufacturing method of a droplet discharge head according to the present invention includes an electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a driving signal to the individual electrode are formed, and a portion corresponding to the mounting portion. A cavity substrate in which a first hole portion opened and a pressure chamber for droplet discharge are formed at positions facing the individual electrodes, and a second hole portion and pressure that are open to communicate with the first hole portion Forming a laminate in which a reservoir substrate on which a reservoir for supplying droplets to the chamber is formed is laminated, and shielding for isolating the mounting portion, the first hole portion, and the second hole portion Inserting the wall into the first hole and the second hole in the laminate, and mounting the driver IC on the mounting portion of the laminate with an anisotropic conductive adhesive inside the shielding wall. Features.

According to the above-described configuration in which the mounting portion, the first hole portion, and the shielding wall for isolating the second hole portion are provided, and the driver IC is mounted inside the shielding wall, the driver IC is released when mounting the driver IC. Gas does not flow out of the shielding wall. That is, since gas does not adhere to the reservoir substrate, the adhesive bonding strength between the reservoir substrate and the nozzle substrate does not decrease. Therefore, the reservoir substrate and the nozzle substrate can be reliably bonded. In addition, since the reservoir substrate and the nozzle substrate can be securely bonded to each other, it is possible to provide a manufacturing method with a high yield.
In addition, since the driver IC and the individual electrode are mounted with an anisotropic conductive adhesive, the driver IC and the individual electrode can be electrically connected.

  The method for manufacturing a droplet discharge head according to the present invention is characterized in that a driver IC is mounted on the mounting portion of the laminate using the driver IC mounting tool having the shielding wall. According to the above configuration in which the driver IC is mounted using the driver IC mounting tool having the shielding wall, the gas released when the driver IC is mounted does not flow out of the shielding wall. That is, since gas does not adhere to the reservoir substrate, the adhesive bonding strength between the reservoir substrate and the nozzle substrate does not decrease. Therefore, the reservoir substrate and the nozzle substrate can be reliably bonded. In addition, since the reservoir substrate and the nozzle substrate can be securely bonded to each other, it is possible to provide a manufacturing method with a high yield.

  The manufacturing method of the droplet discharge head according to the present invention is characterized in that in the step of mounting the driver IC on the mounting portion of the stacked body, the mounting portion and the driver IC are aligned by pins. Since the alignment between the electrode substrate and the driver IC is performed using pins, it is possible to prevent the positional deviation between the electrode substrate and the driver IC. That is, the driver IC can be reliably mounted on the electrode substrate.

  The manufacturing method of the droplet discharge head according to the present invention is characterized in that in the step of mounting the driver IC on the mounting portion of the stacked body, the mounting portion and the driver IC are aligned by a camera. Since the alignment between the electrode substrate and the driver IC is performed using the camera, it is possible to prevent the positional deviation between the electrode substrate and the driver IC. That is, the driver IC can be reliably mounted on the electrode substrate.

  A method for manufacturing a droplet discharge device according to the present invention includes the method for manufacturing a droplet discharge head according to any one of claims 1 to 7. Therefore, since the method for manufacturing any one of the above-described droplet discharge heads is included, the above-described effects can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is an exploded perspective view of a droplet discharge head 100 according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing an AA section in a state where the droplet discharge head 100 is assembled. The droplet discharge head 100 is of a face eject type that discharges droplets from nozzle holes provided on the surface side of the nozzle substrate, and is of an electrostatic drive type that is driven by electrostatic force. . FIG. 1 also shows a part of an FPC (Flexible Printed Circuit) for supplying a drive signal.

  As shown in FIG. 1, the droplet discharge head 100 does not have a three-layer structure like a general electrostatic drive type droplet discharge head, but an electrode substrate 4, a cavity substrate 3, a reservoir substrate 2, and a nozzle substrate 1. It is characterized by a four-layer structure composed of four substrates. 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 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 substrate 4, the cavity substrate 3, the reservoir substrate 2, and the nozzle substrate 1 are bonded in this order. Further, the droplet discharge head 100 is provided with a driver IC 15 that supplies a drive signal to the individual electrode 17. The electrode substrate 4, the cavity substrate 3 and the reservoir substrate 1 constitute a laminate.

[Electrode substrate 4]
The electrode substrate 4 may be formed of glass such as borosilicate glass. Here, a case where the electrode substrate 4 is formed of borosilicate glass is shown as an example, but the present invention is not limited to this. For example, the electrode substrate 4 may be formed of single crystal silicon. A concave portion (glass groove) 12 is formed in the electrode substrate 4. The recess 12 may be formed with a depth of 0.3 μm, for example. In addition, the individual electrodes 17 are formed inside the recess 12 so as to face a diaphragm 8 described later at a constant interval. The individual electrode 17 is preferably made by sputtering ITO (Indium Tin Oxide) with a thickness of 0.1 μm, for example.

  The concave portion 12 is patterned in a slightly larger shape similar to these shapes so that a part of the concave electrode 12 can be attached to the individual electrode 17, and the other portion (center portion) can be attached with the driver IC 15. A pattern is formed. The driver IC 15 is installed at the center. One end of the individual electrode 17 is connected to the driver IC 15, and a drive signal is supplied from the driver IC 15.

  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. Two electrode rows extending in the short side direction of 17 are formed. 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. What should I do?

  In the droplet discharge head 100, the driver IC 15 is formed between two electrode rows and is connected to both electrode rows. 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. Furthermore, since the number of driver ICs 15 can be reduced, the cost required for manufacturing can be reduced, and the droplet discharge head 100 can be downsized.

  An ink supply hole 11 is formed in the electrode substrate 4. The ink supply hole 11 passes through the electrode substrate 4. Further, the FPC mounting portion 21 is formed on the electrode substrate 4. A sealing member 14 for sealing the IC output mounting portion 18 and the gap 13 is formed after the electrode substrate 4 and the cavity substrate 3 are joined. The sealing member 14 will be described in detail later. (See FIG. 2). Further, here, a case where two driver ICs 15 are installed is shown as an example, but the present invention is not limited to this. For example, these driver ICs 15 may be constituted by one IC or may be constituted by three or more ICs.

[Cavity substrate 3]
The cavity substrate 3 is made of, for example, single crystal silicon, and a plurality of pressure chambers (or discharge chambers) 7 whose bottom walls are the diaphragms 8 are formed. The pressure chambers 7 are formed in two rows corresponding to the electrode rows of the individual electrodes 17. In addition, a first hole 22 is formed in the cavity substrate 3 so as to penetrate the cavity substrate 3 between the electrode arrays. Further, the cavity substrate 3 has a common electrode 16 for applying a voltage to the diaphragm 8. The common electrode 16 is connected to the FPC 30.

  The cavity substrate 3 is made of single crystal silicon, and an insulating film (not shown) made of TEOS (Tetra Ethyl Ortho Silicate) is formed on the entire surface by plasma CVD (Chemical Vapor Deposition). 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.

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.

  When the electrode substrate 4 and the cavity substrate 3 are joined, a vibration chamber (gap) 13 that is a gap is formed between the individual electrode 17 and the diaphragm 8. The vibration chamber 13 is formed to have a depth of 0.2 μm, for example. In addition, the ink supply hole 11 penetrating the cavity substrate 3 is formed in the cavity substrate 3.

[Reservoir substrate 2]
The reservoir substrate 2 is made of, for example, single crystal silicon, and two reservoirs 10 for supplying droplets to the pressure chamber 7 are formed, and droplets from the reservoir 10 to the pressure chamber 7 are formed on the bottom surface of the reservoir 10. A supply hole 9 for transfer is formed. An ink supply hole 11 that penetrates the bottom surface of the reservoir 10 is formed on the bottom surface of the reservoir 10. The ink supply hole 11 formed in the reservoir substrate 2, the ink supply hole 11 formed in the cavity substrate 3, and the ink supply hole 11 formed in the electrode substrate 4 are the reservoir substrate 2, the cavity substrate 3, and the electrode substrate 4. Are connected to each other in the joined state, and are for supplying droplets to the reservoir 10 from the outside (see FIG. 2). Further, a second hole 23 that penetrates the reservoir substrate 2 is formed between the reservoirs 10 of the reservoir substrate 2.

  As shown in FIG. 2, the first hole portion 22 provided in the cavity substrate 3 and the second hole portion 23 provided in the reservoir substrate 2 communicate with each other to form an accommodating portion 24. The driver IC 15 is accommodated in the accommodating portion 24. Further, nozzle communication holes 6 are formed in portions of the reservoir substrate 2 other than the reservoir 10 so as to communicate with the respective pressure chambers 7 and to transfer droplets from the pressure chambers 7 to the nozzle holes 5 described later. The nozzle communication hole 6 penetrates the reservoir substrate 2 and communicates with one end of the pressure chamber 7 opposite to one end with which the supply hole 9 communicates.

[Nozzle substrate 1]
The nozzle substrate 1 is made of, for example, a silicon substrate having a thickness of 100 μm, and a plurality of nozzle holes 5 communicating with the respective nozzle communication holes 6 are formed. The nozzle holes 5 are formed in two stages to improve the straightness when discharging droplets (see FIG. 2). Further, when the electrode substrate 4, the cavity substrate 3, the reservoir substrate 2 and the nozzle substrate 1 are bonded, when the silicon substrate and the borosilicate glass substrate are bonded, the silicon substrates are bonded to each other by anodic bonding. If so, it can be joined by direct joining. Further, the substrates made of silicon can be bonded using an adhesive. Here, the nozzle substrate 1 and the reservoir substrate 2 are adhesively bonded using an epoxy adhesive.

  As shown in FIG. 2, in the droplet discharge head 100, the driver IC 15 is accommodated in the accommodating portion 24, and the accommodating portion 24 is closed by the nozzle substrate 1, the reservoir substrate 2, the cavity substrate 3, and the electrode substrate 4. ing. That is, the nozzle substrate 1 forms the upper surface of the housing portion 24, the electrode substrate 4 forms the lower surface of the housing portion 24, and the cavity substrate 3 and the reservoir substrate 2 form the side surfaces of the housing portion 24, thereby closing the housing portion 24. It is like that. In addition, it is desirable that the accommodating portion 24 be sealed in order to protect the driver IC 15 from liquid droplets and outside air.

The sealing member 14 seals the gap 13 between the diaphragm 8 and the individual electrode 17. The sealing member 14 is formed of, for example, silicon oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), silicon oxynitride (SiON), silicon nitride (SiN), polyparaxylylene, or the like having low moisture permeability. Good. In addition, polyparaxylylene is a crystalline polymer resin and has properties that are excellent in moisture permeation prevention and chemical resistance. If these materials are formed by sputtering, CVD, or the like, the sealing member 14 having low moisture permeability can be formed small, and the droplet discharge head 100 can be further downsized.

  Next, 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 from the reservoir 10 to the pressure chamber 7 through the supply hole 9. The driver IC 15 receives a drive signal (not shown) from a control unit (not shown) of the droplet discharge device via an FPC internal wiring (IC input) 32 of the FPC 30 and an IC input mounting unit 20 (see FIG. 1) provided on the electrode substrate 4. Pulse voltage).

  Then, a pulse voltage of about 0 V to 40 V is applied from the driver IC 15 to the individual electrode 17 to charge the individual electrode 17 positively, and the corresponding diaphragm 8 is connected to the droplet discharge device via the FPC internal wiring 31 (COM). A drive signal (pulse voltage) is supplied from a control unit (not shown) to be negatively charged. If it does so, the diaphragm 8 will be attracted | sucked by the individual electrode 17 side by an electrostatic force, and will be bent. Next, when this pulse voltage is turned off, the electrostatic force applied to the diaphragm 8 disappears and the diaphragm 11 is restored. 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. Thereafter, the droplet is replenished from the reservoir 10 into the pressure chamber 7 through the supply hole 9 and returns to the initial state.

  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. The FPC 30 is connected to the driver IC 15 so that the longitudinal direction of the FPC 30 is parallel to the short side direction of the individual electrodes 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 an explanatory view showing that gas is released from the binder in the anisotropic conductive adhesive. As shown in FIG. 2, the driver IC 15 is mounted in the housing portion 24. The driver IC 15 is mounted by attaching an anisotropic conductive adhesive (ACF) or an anisotropic conductive paste (ACP), which is an anisotropic conductive adhesive. Here, a case where the driver IC 15 is mounted using ACF is shown as an example.

  This anisotropic conductive adhesive is composed of an adhesive binder (hereinafter simply referred to as a binder) in which conductive particles having a diameter of several μm are mixed, which plays a role of enabling electrical connection. In order to fix the driver IC 15 using this ACF, the driver IC 15 is generally fixed by heating and pressurizing to cure the ACF (detailed later). And when heating, gas is emitted from a binder. If this gas adheres to the reservoir substrate 2, the adhesive bonding strength between the reservoir substrate 2 and the nozzle substrate 1 will decrease.

  The reservoir substrate 2 is generally provided with a primer layer as a base in order to further strengthen the adhesive bonding strength with the nozzle substrate 1. If the gas released from the binder adheres to the primer layer, the gas becomes an adhesion inhibitor (foreign matter) and the adhesive bonding strength is reduced. Therefore, in the first embodiment, a mask is provided on the reservoir substrate 2 to prevent gas from adhering to the reservoir substrate 2 (see FIG. 8). In the second embodiment, the driver IC mounting tool is provided with a shielding wall so that gas does not adhere to the reservoir substrate 2 (see FIG. 9).

  Here, a general mounting process of the driver IC 15 will be described. First, a driver IC 15 and a substrate (for example, electrode substrate 4) on which the driver IC 15 is installed are prepared. And ACF is affixed on the installation location of driver IC15 on a board | substrate. Here, a case where the ACF is attached to the substrate will be described as an example, but the ACF may be attached to a terminal portion of the driver IC 15.

  Next, the driver IC 15 is temporarily bonded onto the substrate. This temporary pressure bonding is performed by a temporary pressure bonding apparatus. After the substrate and the driver IC 15 are placed on the temporary pressure bonding apparatus, alignment is performed based on the alignment mark. For this alignment, the alignment mark may be recognized by a camera, or the alignment mark may be recognized by a pin. When the alignment is completed, provisional pressure bonding is performed. For example, the driver IC 15 is temporarily bonded to the substrate at a temperature of 70 ° C. and a pressure of 1 MPa. As described above, since the temporary pressure bonding is performed at a temperature that is not so high, even if the gas is released from the binder, the amount is not enough to reduce the adhesive bonding strength.

  When the temporary pressure bonding is completed, the driver IC 15 is finally pressure bonded to the substrate. That is, the temporary pressure bonding is simply performed in consideration of the positional deviation between the substrate and the driver IC 15, but the main pressure bonding is performed to actually fix the driver IC 15 to the substrate. This main press-bonding is performed by a main press-bonding apparatus. For example, the driver IC 15 is permanently bonded to the substrate at a temperature of 220 ° C. and a pressure of 80 MPa. Since this main pressure bonding is performed at a high temperature, a large amount of gas is released from the binder.

  Therefore, it is necessary to prevent the gas released in the main pressure bonding process from adhering to the reservoir substrate 2. Therefore, in the present invention, a mask is provided on the reservoir substrate 2 or a shielding wall is provided on the driver IC mounting tool so that gas does not adhere to the reservoir substrate 2. In addition, although the case where temporary crimping and this crimping | compression-bonding are performed with another apparatus was demonstrated to the example, it is not limited to this. For example, the temporary pressure bonding and the main pressure bonding may be performed with the same apparatus.

  FIG. 4 is a perspective view of the droplet discharge head 100. Here, the state before the cutting of the three droplet discharge heads 100 is shown as an example for convenience. A stage before the droplet discharge head 100 is cut (diced) one by one is shown. The droplet discharge heads 100 shown here may be used as they are without being cut one by one. As shown in the figure, since the driver IC 15 is housed inside the droplet discharge head 100, the droplet discharge head 100 can be downsized. In addition, it is possible to easily realize multiple nozzles.

  FIG. 5 is a schematic block diagram showing a control system of a droplet discharge device on which the droplet discharge head 100 is mounted. In the following description, it is assumed that the droplet discharge device is a general ink jet printer. Hereinafter, a control system of a droplet discharge device on which the droplet discharge head 100 is mounted will be described with reference to the drawings. However, the control system of the droplet discharge device on which the droplet discharge head 100 is mounted is not limited to the case shown here.

  The ink jet printer includes a control device 50 for driving and controlling the droplet discharge head 100. The control device 50 is configured around a CPU (central processing unit) 51. The CPU 51 receives print information from an external device 60 such as a personal computer or a remote control device (remote control). This print information is input via the bus 52 or input by a wireless signal such as an infrared signal. The CPU 51 is connected to a ROM 54, a RAM 55, and a character generator 56 via an internal bus 53.

  The control device 50 uses the storage area in the RAM 55 as a work area, executes a control program stored in the ROM 54, and drives the droplet discharge head 100 based on character information generated from the character generator 56. Control signal is generated. The control signal becomes a drive control signal corresponding to the print information via the logic gate array 57 and the drive pulse generation circuit 58, and is supplied to the driver IC 15 built in the droplet discharge head 100 via the connector 65. In addition, it is supplied to the COM generation circuit 59. The driver IC 15 is also supplied with a drive pulse signal V3 for printing, a control signal LP, a polarity inversion control signal REV, and the like (see FIG. 4). Note that the COM generation circuit 59 may be configured by a common electrode IC (not shown) for generating a drive pulse, for example.

  The COM generation circuit 59 outputs a drive signal to be applied to the common electrode 16 of the droplet discharge head 100, that is, each diaphragm 8, from a common output terminal COM (not shown) based on the supplied signals. ing. In the driver IC 15, a drive signal to be applied to each individual electrode 17 is applied to each individual electrode 17 based on each supplied signal and the drive voltage Vp supplied from the power supply circuit 70. To output. A potential difference between the output of the common output terminal COM 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. 6 is a schematic block diagram showing an example of the internal configuration of the driver IC 15 and the COM generation circuit 59. The driver IC 15 and the COM generation circuit 59 supply driving signals to the 64 individual electrodes 17 and the diaphragm 8 in one set. Further, an example is shown in which the driver IC 15 is a CMOS 64-bit output high voltage driver 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 81. The shift register 81 is an XSCL pulse that is a basic clock pulse that synchronizes the DI signal input of 64-bit length transmitted from the logic gate array 57 as serial data with the DI signal. It is a static shift register that shifts up data by a signal input and stores it in a register in the shift register 81. The DI signal is a control signal indicating selection information for selecting each of the 64 individual electrodes 17 by ON / OFF, and this signal is transmitted as serial data.

  The driver IC 15 has a 64-bit latch circuit 82. The latch circuit 82 latches the 64-bit data stored in the shift register 81 with a control signal (latch pulse) LP to store the data. This is a static clutch that outputs the data to the 64-bit inversion circuit 83 as a signal. In the latch circuit 82, the DI signal of the serial data is converted into a 64-bit parallel signal for outputting 64 segments for driving each diaphragm 11.

  The inverting circuit 83 outputs an exclusive OR of the signal input from the latch circuit 82 and the REV signal to the level shifter 84. The level shifter 84 is a level interface circuit that converts the voltage level of the signal from the inverting circuit 83 from the logic system voltage level (5 V level or 3.3 V level) to the head drive system voltage level (0 to 45 V level). The SEG driver 85 is a 64 channel transmission gate output, and outputs either a drive voltage pulse input or a GND input to the segment outputs SEG1 to SEG64 by the input of the level shifter 84. A COM driver 86 built in the COM generation circuit 59 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 system voltage level signals that are transmitted from the logic gate array 57 to the driver IC 15. In this way, by configuring the driver IC 15 and the COM generation circuit 59, even when the number of segments to be driven (the number of diaphragms 8) increases, the driving voltage for driving the diaphragm 8 of the droplet discharge head 100 can be easily achieved. It is possible to switch between pulse and GND.

  7 and 8 are longitudinal sectional views showing an example of the manufacturing process of the droplet discharge head 100. FIG. An example of a method for manufacturing the droplet discharge head 100 is shown here, but the present invention is not limited to this. First, the cavity substrate 3 having a thickness of, for example, 525 μm is anodically bonded to the electrode substrate 4 on which the individual electrodes 17 and the ink supply holes 11 are formed (a). The droplet discharge head 100 is manufactured by forming the electrode substrate 4 of borosilicate glass and forming two electrode rows on the electrode substrate 4.

  Here, an example of the manufacturing method of the electrode substrate 4 will be briefly described. First, a resist is applied to the entire surface of the glass substrate and patterned into a predetermined shape, and then etched with a hydrofluoric acid aqueous solution or the like to form a recess 12 to peel off the resist. Then, ITO is formed on the entire surface where the recess 12 is formed by sputtering or the like, a resist is applied to the surface of the ITO and patterned, and after the individual electrodes 17 are formed by etching, the resist is peeled off. The ink supply hole 11 can be formed by a drill or the like.

  Next, the cavity substrate 3 is thinned by mechanical grinding so that the thickness of the cavity substrate 3 is 140 μm (b). In addition, it is desirable to remove the work-affected layer generated on the surface of the cavity substrate 3 with a potassium hydroxide aqueous solution or the like after mechanical grinding. Then, an oxide film is formed on the surface of the cavity substrate 3 by plasma CVD using a TEOS film (Tetra Ethyl Ortho Silicate) or the like (c), and then a resist is applied to the oxide film surface to apply the pressure chamber 7, the first hole 22, and the ink supply. The shape of the hole 11 is patterned (d).

  Then, for example, the cavity substrate 3 is etched with an aqueous potassium hydroxide solution to form the pressure chamber 7, the first hole 22, and the ink supply hole 11, and the oxide film is peeled off (e). If the boron doped layer is formed on the cavity substrate 3 as described above, the boron doped layer remains as a thin film such as the diaphragm 8. Thereafter, the silicon thin film remaining in the first hole 22 and the ink supply hole 11 is removed by RIE (Reactive Ion Etching) or the like to form the first hole 22 and the ink supply hole 11 (f).

  Next, the sealing member 14 is formed in the first hole 22 to seal the gap 13 between the individual electrodes 17 (g). At this time, a portion of the individual electrode 17 that is not sealed with the sealing member 14 is covered with the sealing member 14. In the case where a resin such as polyparaxylene is used as a material, the sealing member 14 can be formed by applying a sealing material at a predetermined position with a needle. Further, when a metal material such as silicon oxide, aluminum oxide, silicon oxynitride, or silicon nitride is used as the material of the sealing member 14, it can be formed by CVD using a mask 90 made of silicon or the like.

  Next, the reservoir substrate 2 is bonded to the surface of the cavity substrate 3 where the pressure chambers 7 are formed (h). At this time, the first hole portion 22 and the second hole portion 23 communicate with each other to form the accommodating portion 24. In the reservoir substrate 2, a reservoir 10 for supplying droplets to the pressure chamber 7 in advance, a supply hole 9 for transferring droplets from the reservoir 10 to the pressure chamber 7, and droplets from the pressure chamber 7 to the nozzle hole 5 are provided. The nozzle communication hole 6 to be transferred and the second hole portion 23 are preferably formed. The reservoir substrate 2 is formed by forming a silicon oxide film on the silicon substrate, patterning a resist on the surface of the silicon oxide film to etch a predetermined portion of the silicon oxide film, and then etching the silicon substrate with a potassium hydroxide aqueous solution or the like. Can be formed.

  Here, a mask 90 provided with an opening corresponding to the accommodating portion 24 is set on the reservoir substrate 2 (i). Here, an example is shown in which the driver IC 15 is mounted by attaching ACF to the electrode substrate 4 on which the driver IC 15 is installed. As described above, when the gas released from the binder in the anisotropic conductive adhesive adheres to the reservoir substrate 2, the adhesive bonding strength between the reservoir substrate 2 and the nozzle substrate 1 is reduced. In order to prevent this, the mask 90 is set on the reservoir substrate 2.

  In many cases, the reservoir substrate 2 is generally provided with a primer layer as a base in order to further strengthen the adhesive bonding with the nozzle substrate 1. If the gas released from the binder adheres to the primer layer, the gas becomes an adhesion inhibitor (foreign matter) and the adhesive bonding strength is reduced. Therefore, after bonding the reservoir substrate 2 to the cavity substrate 3 and before mounting the driver IC 15, a mask 90 is set on the reservoir substrate 2 to prevent a decrease in adhesive bonding strength between the reservoir substrate 2 and the nozzle substrate 1. ing.

  The mask 90 used here is not particularly limited as long as the released gas does not enter between the reservoir substrate 2 (primer layer) and the mask 90. For example, a mask 90 made of a material or a thickness that does not enter between the reservoir substrate 2 and the mask 90 may be used. Further, it may be a mask 90 substrate made of borosilicate glass or single crystal silicon, or a protective tape such as a dicing tape. However, when using a dicing tape, it is necessary to consider the heat resistance of the dicing tape. As described above, the alignment between the reservoir substrate 2 and the mask 90 may be performed by alignment with pins or a camera.

  After the formation of the mask 90 on the reservoir substrate 2 is completed, the driver IC 15 is prepared, and the driver IC 15 is connected to the individual electrodes 17 constituting the two electrode rows in the first hole portion 22. It is mounted on the substrate 4 (j). After confirming the mounting position of the driver IC 15 in the housing portion 24, temporary crimping is performed. This temporary pressure bonding may be performed, for example, at a temperature of 70 ° C. and a pressure of 1 MPa. After the temporary pressure bonding, the anisotropic conductive adhesive is cured and the main pressure bonding is performed to ensure the bonding. The main press bonding may be performed, for example, at a temperature of 220 ° C. and a pressure of 80 MPa. When the main pressure bonding is completed, the mask 90 is peeled off. Even if the mask 90 is peeled off, the anisotropic conductive adhesive is already cured, so that no gas is released. That is, the gas will not be released unless the ACF is heated.

  Then, the nozzle substrate 1 in which the nozzle holes 5 are formed by ICP (Inductively Coupled Plasma) discharge or etching or the like is bonded to the reservoir substrate 2 using an adhesive such as an epoxy adhesive (k). Finally, the bonded substrate to which the electrode substrate 4, the cavity substrate 3, the reservoir substrate 2, and the nozzle substrate 1 are bonded is cut (diced) to complete individual droplet discharge heads 100.

  As described above, the first hole portion 22 is provided in the cavity substrate 3, the second hole portion 23 is provided in the reservoir substrate 2, and the accommodating portion 24 is formed by the first hole portion 22 and the second hole portion 23. In addition, since the driver IC 15 is accommodated in the accommodating portion 24, the size of the droplet discharge head 100 can be reduced. Therefore, the distance between the printing paper and the nozzle hole 5 can be reduced, and high-definition printing is possible. Further, since the surface on which the nozzle holes 5 are formed can be flattened, wiping (a step of removing unnecessary droplets) can be easily performed. Further, since the accommodating portion 24 is closed by the nozzle substrate 1, the cavity substrate 3, the reservoir substrate 2 and the electrode substrate 4, it is not necessary to provide a layer for protecting the driver IC 15 from droplets. It becomes possible to protect from.

Embodiment 2. FIG.
FIG. 9 is a longitudinal sectional view showing another example of the manufacturing process of the droplet discharge head 100. The manufacturing process of the droplet discharge head 100 according to the second embodiment of the present invention will be described with reference to the drawings. In the second embodiment, a case where the driver IC 15 is mounted using the driver IC mounting tool 91 will be described. The difference between the second embodiment and the first embodiment will be described, and the description of the configuration of the droplet discharge head 100 and other manufacturing processes that are the same as those of the first embodiment will be omitted.

  The driver IC 15 is mounted by a driver IC mounting tool 91. The driver IC mounting tool 91 is provided with a shielding wall 92 so that gas released from the binder does not adhere to the reservoir substrate 2. The shielding wall 92 extends from the cavity substrate 3 in the accommodating portion 24 toward the opening of the reservoir substrate 2 so as not to release the gas out of the driver IC mounting tool 91. The driver IC mounting tool 91 is for fixing the driver IC 15 by heating and pressurizing, but by providing the shielding wall 92, it is possible to prevent diffusion of the released gas at the same time.

  That is, in the mounting process of the driver IC 15, the mounting of the driver IC 15 and the prevention of gas adhesion on the reservoir substrate 2 are realized at the same time. In the first embodiment, it is necessary to set the mask 90 on the reservoir substrate 2 and finally peel off the mask 90. However, in the second embodiment, the steps of setting and peeling the mask 90 can be omitted. . Therefore, in addition to the effects described in the first embodiment, the manufacturing process can be further simplified, and it is possible to reduce labor and improve the manufacturing speed.

  FIG. 10 is a perspective view showing an example of a droplet discharge device 150 equipped with the droplet discharge head 100 manufactured by the method of manufacturing a droplet discharge head according to the first and second embodiments. The droplet discharge device 150 is a general ink jet printer. As described above, the droplet discharge head 100 according to the embodiment is small in size and excellent in discharge stability and durability. Further, the droplet discharge device 150 equipped with the droplet discharge head 100 is also small and has high printing performance and high durability.

  In addition to the ink jet printer shown in FIG. 10, the droplet discharge head 100 can be used to manufacture liquid crystal color filters, to form light emitting portions of organic EL display devices, It can also be applied to discharge or the like. Further, the droplet discharge head 100, the manufacturing method thereof, and the droplet discharge device 150 are not limited to the embodiments of the present invention, and can be modified within the scope of the present invention. For example, the sealing member position may be sealed at two places.

It is a disassembled perspective view of the droplet discharge head concerning an embodiment of the invention. It is a longitudinal cross-sectional view which shows the AA cross section of the state by which the droplet discharge head was assembled. It is explanatory drawing which shows that gas is discharge | released from the binder in an anisotropic conductive adhesive. It is a perspective view of a droplet discharge head. 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 a longitudinal cross-sectional view which shows an example of the manufacturing process of a droplet discharge head. It is a longitudinal cross-sectional view which shows an example of the manufacturing process of a droplet discharge head. It is a longitudinal cross-sectional view which shows another example of the manufacturing process of a droplet discharge head. It is the perspective view which showed an example of the droplet discharge apparatus carrying the droplet discharge head manufactured with the manufacturing method of the droplet discharge head which concerns on embodiment.

Explanation of symbols

1 nozzle substrate, 2 reservoir substrate, 3 cavity substrate, 4 electrode substrate, 5 nozzle hole, 6 nozzle communication hole, 7 pressure chamber, 8 diaphragm, 9 supply hole, 10 reservoir, 11 ink supply hole, 12 recess (glass groove) ), 13 Vibration chamber (gap), 14 Sealing member, 15 Driver IC, 16 Common electrode, 17 Counter electrode (Individual electrode ITO), 18 IC output (SEG) mounting part, 20 IC input mounting part, 21 FPC mounting part , 22 1st hole, 23 2nd hole, 30 FPC, 31 FPC internal wiring (COM), 32 FPC internal wiring (IC input), 50 control device, 51 CPU, 52 bus, 53 internal bus, 54 ROM, 55 RAM, 56 Character generator, 57 Theoretical gate array, 58 Drive pulse generation circuit, 59 COM generation circuit, 60 External device, 65 Connector, 7 0 power supply circuit, 90 mask, 91 driver IC mounting tool, 92 shielding wall, 100 droplet ejection head, 150 droplet ejection device.

Claims (7)

An electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a drive signal to the individual electrode are formed, a first hole portion that opens a portion corresponding to the mounting portion, and the individual electrode A cavity substrate having a pressure chamber for discharging liquid droplets formed at opposing positions, a second hole portion opened so as to communicate with the first hole portion, and a droplet for supplying the pressure chamber to the pressure chamber Forming a laminate in which a reservoir substrate and a reservoir substrate are laminated;
Setting a mask having an opening corresponding to the second hole on the reservoir substrate of the laminate;
And a step of mounting a driver IC on the mounting portion of the laminated body with an anisotropic conductive adhesive after the mask is set. A method of manufacturing a droplet discharge head, comprising: An electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a drive signal to the individual electrode are formed, a first hole portion that opens a portion corresponding to the mounting portion, and the individual electrode A cavity substrate having a pressure chamber for discharging liquid droplets formed at opposing positions, a second hole portion opened so as to communicate with the first hole portion, and a droplet for supplying the pressure chamber to the pressure chamber Forming a laminate in which a reservoir substrate and a reservoir substrate are laminated;
Attaching a protective tape to a portion of the laminate body other than the second hole in the reservoir substrate;
And a step of mounting a driver IC on the mounting portion of the laminated body with an anisotropic conductive adhesive after applying the protective tape. A method of manufacturing a droplet discharge head, comprising: An electrode substrate on which an individual electrode and a mounting portion for mounting a driver IC that supplies a drive signal to the individual electrode are formed, a first hole portion that opens a portion corresponding to the mounting portion, and the individual electrode A cavity substrate having a pressure chamber for discharging liquid droplets formed at opposing positions, a second hole portion opened so as to communicate with the first hole portion, and a droplet for supplying the pressure chamber to the pressure chamber Forming a laminate in which a reservoir substrate and a reservoir substrate are laminated;
Inserting a shielding wall for isolating the mounting part, the first hole part, and the second hole part into the first hole part and the second hole part in the laminate,
And a step of mounting a driver IC on the mounting portion of the laminate with an anisotropic conductive adhesive inside the shielding wall. The method of manufacturing a droplet discharge head according to claim 3, wherein a driver IC is mounted on the mounting portion of the stacked body using a driver IC mounting tool having the shielding wall. In the step of mounting the driver IC on the mounting portion of the laminate,
The mounting part and the driver IC are aligned by pins.
The method for manufacturing a droplet discharge head according to any one of claims 1 to 4. In the step of mounting the driver IC on the mounting portion of the laminate,
The mounting unit and the driver IC are aligned by a camera.
The method for manufacturing a droplet discharge head according to any one of claims 1 to 4. The manufacturing method of the droplet discharge head in any one of the said Claims 1-6 is included.
A method of manufacturing a droplet discharge device.

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