JP2010142016A - Electrostatic actuator, droplet discharge head, droplet discharge device, and electrostatic device - Google Patents

Abstract

An electrostatic actuator capable of preventing the occurrence of migration or the like and maintaining reliability even when the distance between lead wires is shortened in order to cope with the increase in density of the electrostatic actuator.
A vibrating plate 22 serving as a movable electrode and an individual electrode portion 12A of an electrode 12 serving as a fixed electrode formed on an electrode substrate are provided, and a voltage is applied between the vibrating plate 22 and the individual electrode portion 12A. The electrode substrate 10 is an electrostatic actuator that generates an electrostatic force to drive the diaphragm 22, and the electrode substrate 10 includes a terminal portion 12C for electrically connecting to the driver IC 50, an individual electrode portion 12A, and a terminal portion 12C. The semiconductor device further includes an insulating film 15 for covering and electrically insulating the lead wiring portion 12B and the plurality of lead wiring portions 12B that are electrically connected.
[Selection] Figure 2

Description

  The present invention relates to an electrostatic drive device such as an electrostatic actuator or a droplet discharge head that performs an operation (drive) or the like in which a movable portion is displaced by an applied force in a microfabricated element.

  For example, micro electro mechanical systems (MEMS) that process silicon or the like to form minute elements or the like have made rapid progress. Examples of microfabricated elements formed by microfabrication technology include droplet ejection heads (inkjet heads), micropumps, and variable optical filters used in recording (printing) devices such as droplet ejection printers. And electrostatic actuators such as motors.

  Here, a liquid droplet ejection head using an electrostatic actuator (electro-mechanical energy conversion element) will be described as an example of a microfabricated element. A droplet discharge type recording (printing) apparatus is used for printing in various fields regardless of whether it is for home use or industrial use. In the droplet discharge method, for example, a droplet discharge head having a plurality of nozzles is moved relative to an object, and droplets are discharged to a predetermined position of the object to record printing or the like. . This method uses a color filter for manufacturing a display device using liquid crystal, a display panel using an electroluminescence element such as an organic compound (OLED), a microarray of biomolecules such as DNA and protein. Etc. are also used in the manufacture of

  The droplet discharge head includes a plurality of discharge chambers for storing liquid in a part of the flow path, and is a wall on at least one surface of the discharge chamber (here, a bottom wall, hereinafter referred to as a diaphragm). There is a method in which the pressure in the discharge chamber is increased by changing the shape and the droplets are discharged from each communicating nozzle. When an electrostatic actuator is used for a droplet discharge head, as a force (energy) for displacing a diaphragm, which is a movable part, for example, a diaphragm is used as a movable electrode, and a fixed distance is set to face the diaphragm separately from each other. An electrostatic force (in particular, electrostatic attraction is used here, hereinafter referred to as electrostatic force) generated between the electrodes (hereinafter referred to as individual electrodes) is used.

Then, for example, by supplying electric charges according to an instruction from a control means that performs drive control, a potential difference is generated between the diaphragm and the individual electrode (voltage is applied), an electrostatic force is generated, and the diaphragm is attracted to the individual electrode. To displace them. After that, if the electrostatic force is weakened, stopped, etc., the restoring force (elastic force) that returns the deformed discharge chamber (displaced diaphragm) to return to the equilibrium state becomes larger. It moves away from the individual electrode and returns to its original position. By repeating these steps, the diaphragm is driven to be displaced (see, for example, Patent Document 1).
JP 2004-058288 A

  For example, with respect to a droplet discharge head, in recent years, high-definition printing or the like has been demanded, and the nozzle density has been increasing in order to meet the demand. Along with this, the widths of the individual electrodes corresponding to the respective nozzles constituting the electrostatic actuator are also narrowed, and the density of wirings for supplying electric charges to the individual electrodes is increased. For this reason, the distance between the lead wires for supplying charges to the individual electrodes from the outside is also short, and the wires may be thin.

  Further, by increasing the density, for example, the width of the discharge chamber becomes narrower. Therefore, even if the diaphragm is displaced, the amount of change in the volume of the discharge chamber is reduced, and the amount of liquid that can be discharged is reduced. For this reason, the space between the diaphragm and the individual electrodes (hereinafter referred to as a gap) can be widened to increase the displacement of the diaphragm, but the applied voltage becomes high.

  Here, when the applied voltage is increased, the intensity of the electric field generated by the electric charge flowing through the lead wiring is increased. Long-term driving with a short distance between the lead wires and high electric field strength may cause migration of the lead wires, which may cause interference with other wires, short circuit, disconnection, etc. The reliability of the electric actuator will be reduced.

  Accordingly, the present invention provides an electrostatic actuator that can prevent the occurrence of migration and maintain the reliability even when the distance between the lead wires is shortened in order to cope with the higher density of the electrostatic actuator. It is intended to obtain.

An electrostatic actuator according to the present invention includes a movable electrode and a fixed electrode formed on an electrode substrate, and applies a voltage between the movable electrode and the fixed electrode to generate an electrostatic force to drive the movable electrode. The electrode substrate has a terminal for electrically connecting to the driving device, a lead wire for electrically connecting the individual electrode and the terminal, and a plurality of lead wires for covering and insulating. The insulating film is further provided.
According to the present invention, an exposed portion (an uninsulated portion) is provided by having an insulating film covering a plurality of lead wires, and performing electrical insulation in the lead wires, for example, by exposing only the terminals and the like. ) To increase the distance between the electrodes substantially. For this reason, even if a high voltage is applied between the movable electrode and the fixed electrode, the electric field strength becomes high, and other lead wirings are not disconnected or interfered with each other. Even so, an electrostatic actuator with a long life and high reliability can be obtained.

In addition, the electrostatic actuator according to the present invention covers the fixed film with the insulating film.
According to the present invention, since the insulating film is also coated on the fixed electrode, insulation between the movable electrode and the fixed electrode can also be realized. At this time, since the same formation can be performed in the same process as the insulating film covering the lead wiring, the coating can be realized without increasing the number of processes.

In the electrostatic actuator according to the present invention, the insulating film includes a plurality of stacked films, and the outermost film is a film that is resistant to gas by dry etching.
According to the present invention, an insulating film is formed by laminating a plurality of films, and the outermost film is made resistant to the gas related to anisotropic dry etching. It is possible to prevent film damage or the like in dry etching.

In addition, a droplet discharge head according to the present invention includes the electrostatic actuator described above, and uses at least a part of a discharge chamber filled with a liquid as a movable electrode, and drops from a nozzle communicating with the discharge chamber by displacement of the movable electrode. To discharge.
According to the present invention, since the electrostatic actuator is used as a liquid pressurizing unit of the droplet discharge head, the insulating film covering the plurality of lead wirings prevents migration and the like, and has a long life and reliability. A high droplet discharge head can be obtained.

A droplet discharge device according to the present invention is equipped with the above-described droplet discharge head.
According to the present invention, since the above-described droplet discharge head is mounted, it is possible to obtain a droplet discharge device having a long life and high reliability.

Moreover, the electrostatic drive device according to the present invention includes the above-described electrostatic actuator.
According to the present invention, since the electrostatic actuator described above is mounted on an electrostatic drive device, an electrostatic drive device having a long life and high reliability can be obtained.

Embodiment 1 FIG.
FIG. 1 is an exploded view of a droplet discharge head according to Embodiment 1 of the present invention. FIG. 1 shows a part of a droplet discharge head. In this embodiment, for example, a face eject type droplet discharge head which is a device using an electrostatic actuator driven by an electrostatic method will be described. (In addition, in order to make the components shown and easy to see, the relationship between the sizes of the components (members) in the following drawings including FIG. 1 may be different from the actual one. And the lower side will be described below). Further, specific numerical values for thickness, depth, and the like are examples.

  As shown in FIG. 1, the droplet discharge head according to the present embodiment is configured by stacking four substrates in order from the bottom: an electrode substrate 10, a cavity substrate 20, a reservoir substrate 30, and a nozzle substrate 40. Here, in the present embodiment, the electrode substrate 10 and the cavity substrate 20 are bonded by anodic bonding. Further, the cavity substrate 20 and the reservoir substrate 30, and the reservoir substrate 30 and the nozzle substrate 40 are bonded using an adhesive such as an epoxy resin.

  The electrode substrate 10 serving as the first substrate is mainly composed of a substrate such as a borosilicate heat-resistant hard glass. In the present embodiment, the glass substrate is used, but single crystal silicon may be used as the substrate, for example. On the surface of the electrode substrate 10, a plurality of recesses 11 having a depth of, for example, about 0.3 μm are formed in accordance with the recesses that become discharge chambers 21 formed in the cavity substrate 20 described later. In addition, an electrode 12 is provided on the inside (particularly the bottom) of the recess 11 facing each discharge chamber 21 (vibrating plate 22) of the cavity substrate 20. The electrode 12 includes an individual electrode portion 12A serving as a fixed electrode, a lead wiring portion 12B, and a terminal portion 12C. The electrode 12 is electrically connected to a driver IC 50 serving as a driving device via the terminal portion 12C, and voltage is applied from the driver IC 50 ( Charge supply) or the like. The electrode 12 is formed by depositing ITO (Indium Tin Oxide) with a thickness of 0.1 μm inside the recess 11 by sputtering, for example. And between the diaphragm 22 and the individual electrode portion 12A of the electrode 12, a certain gap (a space surrounded by the recess 11 or the like, a void chamber) in which the diaphragm 22 can be bent (displaced) by the recess 11. Is formed.

  FIG. 2 is a diagram illustrating the relationship between the lead wiring portion 12B and the terminal portion 12C between the electrodes 12. Since the droplet discharge head according to the present embodiment is configured to directly connect the terminal portion 12C and the terminal of the driver IC 50 serving as a driving device, the terminal portion 12C is formed in accordance with the arrangement of the terminals of the driver IC 50. In the present embodiment, it is assumed that the terminals of the driver IC 50 are composed of four rows on one side, and as shown in FIG. 2, for example, an anisotropic conductive material is constructed corresponding to the arrangement of the terminals of the driver IC 50. The terminal portion 12C is formed on the electrode substrate 10 with a predetermined area in consideration of the particle diameter of the conductive particles to be performed. On the other hand, the individual electrode portions 12A are arranged in accordance with the nozzles 41 and are formed with a predetermined area so as to form a line on one side along the longitudinal direction of the droplet discharge head. As described above, since the terminal portion 12C and the individual electrode portion 12A are limited in arrangement, area, and the like, wiring by the lead wiring portion 12B is complicated, and conventionally, the minimum adjacent distance between the electrodes 12 as shown in FIG. May be narrowed.

  Therefore, in the present embodiment, in order to prevent migration and other interference with other electrodes 12 due to the generation of an electric field in the lead wiring portion 12B, insulation that insulates between the lead wiring portion 12B and the other electrode 12 is performed. A film 15 is formed. Thereby, the exposed part in each electrode 12 becomes only the terminal part 12C. Since the distance between the terminal portions 12C is wider than the conventional minimum adjacent distance and has a large area and the like, the reliability of the electrostatic actuator can be maintained for a long time without disconnection or the like. Here, in this embodiment, since the individual electrode portion 12 </ b> A is also insulated from the diaphragm 22, the insulating film 15 is not only the portion where the lead wiring portion 12 is formed, but also each electrode 12. The individual electrode portions 12A are also formed to cover the same film. Here, the insulating film 15 is a single-layer film, but a plurality of films may be stacked. The thickness of the insulating film 15 is not particularly limited, but it is necessary to make the thickness so as not to be affected by the electric field generated between the electrodes 12.

  In addition, the recess 11 is provided with a signal wiring 13 for transmitting an SEG signal that is a signal for controlling individual charge supply to each individual electrode portion 12A from the FPC 51 described later to the driver IC 50. The signal wiring 13 is arranged in a portion directly below the driver IC 50 when the driver IC 50 is accommodated. In addition, the electrode substrate 10 is provided with a through-hole serving as a liquid intake port 14 serving as a flow path for taking in liquid supplied from an external tank (not shown).

The cavity substrate 20 is mainly composed of a silicon single crystal substrate (hereinafter referred to as a silicon substrate). In this embodiment, for example, it is assumed that the silicon substrate has a thickness of about 50 μm and a surface of (110) plane orientation. The cavity substrate 20 is formed with a recess (the bottom wall is formed of a boron-doped layer and is a diaphragm 22 that is a movable electrode) that becomes the discharge chamber 21. In addition, on the lower surface of the cavity substrate 20 (the surface facing the electrode substrate 10), as with the insulating film 15, an insulating film 23 for electrically insulating the diaphragm 22 and the individual electrode portion 12 </ b> A is provided. A film is formed. Here, the insulating film 23 is a silicon oxide film (hereinafter referred to as a chemical vapor deposition (TEOS-pCVD)) method using TEOS (Tetraethyl orthosilicate Tetraethoxysilane). , Referred to as a TEOS film). Although the insulating film 23 is a TEOS film here, for example, Al ₂ O ₃ (aluminum oxide (alumina)) may be used.

  The cavity substrate 20 is also provided with a through-hole serving as the liquid intake 14 (communication with the through-hole provided in the electrode substrate 10). Furthermore, a common electrode terminal 25 is provided which serves as a terminal for supplying a charge having a polarity opposite to that of the individual electrode portion 12A from an external power supply means (not shown) to the substrate (diaphragm 22). Moreover, it has a through-hole which becomes the driver accommodating part 26 for accommodating a driver IC.

  The reservoir substrate 30 is mainly made of a silicon substrate, for example. The reservoir substrate 30 is formed with a recess that serves as a reservoir (common liquid chamber) 31 that supplies liquid to each discharge chamber 21. A through-hole (which communicates with a through-hole provided in the electrode substrate 10) is also provided on the bottom surface of the recess as a liquid intake port 14. A supply port 32 for supplying a liquid from the reservoir 31 to each discharge chamber 21 is formed on the bottom surface of the recess according to the position of each discharge chamber 21. A plurality of nozzle communication holes 33 serving as flow paths between the discharge chambers 21 and the nozzles 41 provided in the nozzle substrate 40 and serving as flow paths for transferring the liquid pressurized in the discharge chambers 21 to the nozzles 41 are provided. It is provided according to each nozzle (each discharge chamber 21). Moreover, it has a through-hole (which communicates with a through-hole provided in the cavity substrate 20) to be a driver housing portion 26 for housing the driver IC 50.

  For the nozzle substrate 40, for example, a silicon substrate is used as a main material. A plurality of nozzles 41 are formed on the nozzle substrate 40. Each nozzle 41 discharges the liquid transferred from each nozzle communication hole 33 to the outside as a droplet. The nozzle substrate 40 of the present embodiment is assumed to have a plurality of nozzles 41 formed in two stages. If the nozzles 41 are formed in a plurality of stages, an improvement in straightness when discharging droplets can be expected. Here, a diaphragm for buffering the pressure applied to the liquid on the reservoir 31 side by the diaphragm 22 may be provided. Here, the nozzle substrate 40 serves as a lid, and the driver IC 50 accommodated in the driver accommodating portion 26 is protected.

  The driver IC 50 is a means for applying a voltage independently to each of the plurality of individual electrode portions 12A in the droplet discharge head to perform charge supply, maintenance, discharge, and the like. In this embodiment, two driver ICs 50 are accommodated, but this number is not limited. An FPC (Flexible Print Circuit) 51 is provided with wiring for transmitting a signal from a drive control means (not shown) to the droplet discharge head side. As described above, the wiring is transmitted to the driver IC 50 through the common electrode terminal 25 and the signal wiring 13 for transmitting a COM signal for common charge supply control to all the diaphragms 22 in the droplet discharge head. It consists of wiring for transmitting SEG signals.

  FIG. 3 is a cross-sectional view of the droplet discharge head. A gap (space, gap) formed between the diaphragm 22 and the individual electrode portion 12 </ b> A is blocked from the outside air without being communicated with the space of the driver accommodating portion 26 by sealing with the sealing material 24. .

  For example, a predetermined voltage is applied to the individual electrode portion 12A selected by the driver IC 50, and it is positively charged. At this time, the diaphragm 22 is relatively negatively charged (for example, a charge having a negative polarity is supplied to the cavity substrate 20 through the common electrode terminal 25 such as FPC). Therefore, an electrostatic force is generated between the selected individual electrode portion 12A and the diaphragm 22, and is attracted to the individual electrode portion 12A and bends. This increases the volume of the discharge chamber 21. When the charge supply is stopped, the diaphragm 22 tries to return to its original state. At that time, the volume of the discharge chamber 21 is also restored, and the liquid pressurized by the pressure is discharged from the nozzle 41 as droplets. Printing or the like is performed when the droplets land on a recording sheet, for example.

  4, 5, and 6 are diagrams illustrating a manufacturing process of the droplet discharge head according to the present embodiment. A manufacturing procedure of the droplet discharge head will be described with reference to FIGS. Here, a plurality of droplet discharge head portions and the like are simultaneously formed in units of wafers, but only a part of them is shown in FIGS.

  One side of the silicon substrate 61 (becomes the bonding surface side with the electrode substrate 10) is mirror-polished to produce, for example, a 220 μm thick substrate (becomes the cavity substrate 20). Next, a boron doped layer (not shown) is formed on the bonding surface side of the silicon substrate 61. Further, as described above, the insulating film 23, which is a TEOS film, is formed on the surface on which the boron-doped layer is formed by, for example, plasma CVD (FIG. 4A).

The electrode substrate 10 is produced in a process different from that shown in FIG. A recess 11 having a predetermined depth is formed on one surface of a glass substrate of about 1 mm. After forming the concave portion 11, the electrode 12 (individual electrode portion 12A, lead wiring portion 12B, terminal portion 12C) and signal wiring 13 (see FIG. 5) are formed at desired positions in the concave portion 11 by using, for example, photolithography or sputtering. (Not shown) at the same time. Further, the insulating film 15 is formed so as to cover the individual electrode portion 12A and the lead wiring portion 12B by using a photolithography method and a sputtering method. Here, as for the insulating film 15, a plurality of films may be laminated as described above. At this time, when anisotropic dry etching is performed on the outermost film in a later step, it is desirable to form the film with a material resistant to the etching gas. For example, when SF ₆ (sulfur hexafluoride), CHF ₃ (trifluoromethane), or CF ₄ (tetrafluoromethane) is used as a gas, a film made of diamond-like carbon (DLC) is used as the outermost surface. In the case of SF ₆ or CF ₄ , Al ₂ O ₃ (aluminum oxide (alumina)) or HfO ₂ (hafnium oxide) may be used as the material. Finally, a hole that becomes the liquid intake 14 is formed in a predetermined shape by a sandblasting method or a cutting process. Thereby, the electrode substrate 10 is produced (FIG. 4B).

  And after heating the silicon substrate 61 and the electrode substrate 10 to 360 degreeC, a negative electrode is connected to the electrode substrate 10, a positive electrode is connected to the silicon substrate 61, and the voltage of 800V is applied and anodic bonding is performed (FIG.4 (c)). ).

  The bonded substrate after anodic bonding (hereinafter referred to as bonded substrate) is thinned by grinding (polishing) the surface of the silicon substrate 61 until the thickness of the silicon substrate 61 becomes, for example, about 60 μm. Thereafter, in order to remove the work-affected layer, the silicon substrate 61 is wet-etched with a potassium hydroxide solution having a concentration of 32 w%. As a result, the thickness of the silicon substrate 61 is reduced to about 50 μm (FIG. 4D).

  Next, a hard mask (hereinafter referred to as a TEOS hard mask) 62 made of a TEOS film is formed on the surface subjected to wet etching by a plasma CVD method. After the TEOS hard mask 62 is formed, resist patterning is performed in order to etch the TEOS hard mask 62 in the portions that become the discharge chamber 21, the driver accommodating portion 26, and the liquid intake port 14. Then, these portions are etched using the hydrofluoric acid aqueous solution until the TEOS hard mask 62 is eliminated, and the TEOS hard mask 62 is patterned, and the silicon substrate 61 is exposed for these portions. The resist is removed after etching.

  Then, the bonded substrate is dipped in a 35 wt% potassium hydroxide (KOH) aqueous solution, and wet etching is performed until the thicknesses of the portions serving as the discharge chamber 21, the driver accommodating portion 26, and the liquid intake port 14 become about 10 μm. . Further, the bonded substrate is immersed in a 3 wt% potassium hydroxide aqueous solution, the boron doped layer is exposed, and the wet etching is continued until it is determined that an etching stop that causes the etching progress to be extremely slow has been effective (FIG. 4). (E)).

  In order to remove the boron dope layer in the portion that becomes the driver accommodating portion 26 and the liquid intake port 14, a silicon mask 63 having an opening in the portion that becomes the driver accommodating portion 26 is attached to the surface of the bonded substrate on the silicon substrate 61 side. Then, for example, RIE dry etching (anisotropic dry etching) is performed, and plasma is applied to the portions that will become the driver accommodating portion 26 and the liquid intake port 14 to open (FIG. 5F).

  Further, a mask 64 having an opening at a portion to be the common electrode terminal 25 is attached to the surface of the bonded substrate on the silicon substrate 61 side. Then, after removing the portion of the TEOS hard mask 62 that will become the common electrode terminal 25, sputtering is performed using, for example, platinum (Pt) as a target to form the common electrode terminal 25 (FIG. 5G).

  Further, for example, in order to prevent moisture permeation through the gap, sealing is performed by depositing the sealing material 24 by plasma CVD using TEOS, vapor deposition, sputtering, or the like. The thickness of the sealing material 24 to be deposited is not particularly limited, but since the gap width is about 0.2 μm, for example, the thinnest part is about 2 to 3 μm or more, for bonding to other substrates. It suffices if it can be deposited in a range that does not affect. As described above, the cavity substrate 20 is manufactured, and a bonded substrate in which the cavity substrate 20 and the electrode substrate 10 are bonded is manufactured (FIG. 5H).

  Then, the driver IC 50 is mounted on the electrode substrate 10, and the terminals of the driver IC 50 and the terminals of the electrodes 12 are made of an anisotropic conductive material such as ACF (Anisotropic Conductive Film) or ACP (Anisotropic Conductive Paste). The part 12C is electrically connected (FIG. 6 (i)).

  Further, the reservoir substrate 30 prepared in a separate process in advance is bonded and bonded from the cavity substrate 20 side of the bonded substrate, for example, with an epoxy adhesive (FIG. 6J). Further, the nozzle substrate 40 manufactured in a separate process is similarly bonded and bonded from the bonded reservoir substrate 30 side using, for example, an epoxy adhesive. Then, dicing is performed along the dicing line, and the wafer is cut into individual chips to complete the droplet discharge head (FIG. 6 (k)).

  As described above, according to the first embodiment, since the lead wiring portion 12B of the electrode substrate 10 is covered with the insulating film 15 to insulate, the lead wiring portion 12B is not exposed, and the lead wiring portion 12B is covered. By preventing the generated electric field from affecting the other electrodes 12, migration or the like can be prevented. Therefore, for example, in order to increase the density of the nozzles 41 and the like, a long-life and highly reliable electrostatic actuator can be obtained even if the discharge chambers 22 and the individual electrode portions 12A are combined to form a high density. . Further, since the insulating film 15 also covers the individual electrode portions 12A, the insulation between the individual electrode portions 12A and the diaphragm 22 can be achieved. At this time, by using the same film as the film covering the lead wiring portion 12B, it is possible to realize the coating of the insulating film 15 on each individual electrode portion 12A without increasing the number of steps. Further, the insulating film 15 (the outermost film in the case where the insulating film 15 is a plurality of films) is a film having resistance to gas by dry etching, so that the insulating film 15 is insulated when dry etching is performed in the manufacturing process. It is possible to prevent the film 15 from being etched and to effectively insulate.

Embodiment 2. FIG.
FIG. 7 is a diagram illustrating a manufacturing process of the droplet discharge head according to the second embodiment of the present invention. In the present embodiment, the procedure relating to the formation of the insulating film 15 when manufacturing the droplet discharge head is different from the procedure described in the first embodiment. In the first embodiment, after the insulating film 15 is formed, the silicon substrate 61 to be the cavity substrate 20 is bonded and processed. In the present embodiment, after the silicon substrate 61 is bonded to the electrode substrate 10, the insulating film 15 is formed on the lead wiring portion 12B. For this reason, the insulating film 15 is not formed on the individual electrode portion 12A. However, the insulation between the diaphragm 22 and the individual electrode portion 12 </ b> A can be ensured by the insulating film 23 formed on the lower surface of the diaphragm 22.

  A manufacturing method according to the second embodiment will be described with reference to FIG. Here, the steps until the sealing material 24 shown in FIG. 5H is formed are basically the same as those described in the first embodiment (FIG. 7A). However, in this embodiment, the insulating film 15 formed on the electrode substrate 10 in FIG. 4B is not formed. Here, the sealing material 24 is basically composed of an insulating material such as silicon oxide, and the insulation between the electrodes 12 can also be achieved by the sealing material 24. And the sealing material 24 and the insulating film 15 can be comprised with the same material. However, since it is necessary to protect the gap in order to form the resist 71 to be performed in the next process, the insulating film 15 cannot be formed in the same process as the formation of the sealing material 24, and the sealing is not performed. It is necessary to carry out after the stop material 24 is formed.

  For example, in order to protect the portion where the insulating film 15 is not formed, such as the terminal portion 12C and the signal wiring 13, a photo resist method is used and a photosensitive agent that becomes a resist film (photoresist) is applied to the driver accommodating portion by, for example, a spray coating method. 26 is applied by spraying. Then, patterning is performed by exposure and development to form a resist 71 (FIG. 7B).

  Then, an insulating film 15 is deposited by sputtering or the like (FIG. 7C). Here, the recesses or the like that become the discharge chambers 21 are protected by a silicon mask 72 or the like so that the insulating film 15 is not deposited.

  When the formation of the insulating film 15 is completed, the resist 71 is peeled off (FIG. 7D). Then, as described in the first embodiment, the driver IC 50 is placed on the electrode substrate 10, the reservoir substrate 30 and the nozzle substrate 40 are joined, and dicing is performed to complete the droplet discharge head.

  As described above, according to the second embodiment, the droplet discharge head is manufactured by depositing the insulating film 15 by sputtering or the like after forming the resist 71 to form a film. The insulating film 15 covering the lead wiring portion 12B can also be formed by a manufacturing method other than the first mode.

Embodiment 3 FIG.
In the above-described embodiment, the face eject type liquid droplet ejection head has been described. However, the present invention can also be applied to, for example, an edge eject type liquid droplet ejection head that ejects liquid droplets from the side surface. Moreover, although the above-mentioned embodiment demonstrated the droplet discharge head comprised by laminating | stacking four board | substrates, the number of the board | substrates laminated | stacked is not limited to four. For example, by forming the reservoir on the cavity substrate 20, the present invention can also be applied to a three-layer droplet discharge head that does not have the reservoir substrate 30.

Embodiment 4 FIG.
FIG. 8 is an external view of a droplet discharge apparatus (printer 100) using the droplet discharge head manufactured in the above embodiment. FIG. 9 is a diagram illustrating an example of main constituent means of the droplet discharge device. 8 and 9 is intended for printing by a droplet discharge method (inkjet method). Further, it is a so-called serial type device. In FIG. 9, a drum 101 that supports a printing paper 110 that is a substrate to be printed and a droplet discharge head 102 that discharges ink to the printing paper 110 and performs recording are mainly configured. Although not shown, there is an ink supply means for supplying ink to the droplet discharge head 102. The print paper 110 is held by being crimped to the drum 101 by a paper crimping driver 103 provided parallel to the axial direction of the drum 101. A feed screw 104 is provided parallel to the axial direction of the drum 101, and the droplet discharge head 102 is held. As the feed screw 104 rotates, the droplet discharge head 102 moves in the axial direction of the drum 101.

  On the other hand, the drum 101 is rotationally driven by a motor 106 via a belt 105 or the like. Further, the print control unit 107 drives the feed screw 104 and the motor 106 based on the print data and the control signal, and although not shown here, drives the oscillation drive circuit to vibrate the diaphragm 4, Printing is performed on the print paper 110 while controlling.

  Here, the liquid is ejected onto the print paper 110 as ink, but the liquid ejected from the droplet ejection head is not limited to ink. For example, in an application to be ejected to a substrate to be a color filter, a light emitting element is to be ejected to a substrate of a display panel (OLED or the like) using an electroluminescent element such as a liquid containing a pigment for a color filter or an organic compound. For example, a liquid containing a conductive metal and a liquid containing a conductive metal may be discharged from a droplet discharge head provided in each device. In addition, when the droplet discharge head is used as a dispenser and used for discharging onto a substrate that is a microarray of biomolecules, DNA (Deoxyribo Nucleic Acids: deoxyribonucleic acid), other nucleic acids (for example, Ribo Nucleic Acid: ribonucleic acid, Peptide (Nucleic Acids: peptide nucleic acids, etc.) A liquid containing a probe such as a protein may be discharged. In addition, it can also be used for discharging dyes such as cloth.

Embodiment 5 FIG.
In the above-described embodiment, the droplet discharge head has been described as an example. However, the present invention is not limited to the droplet discharge head, and an electrostatic drive device in which a plurality of electrostatic actuators by other fine processing are arranged. It can also be applied to connection with external power sources.

2 is an exploded view of a droplet discharge head according to Embodiment 1. FIG. It is a figure showing the relationship between the lead wiring part 12B between the electrodes 12, and the terminal part 12C. It is a figure showing the cross section of a droplet discharge head. FIG. 6 is a diagram (part 1) illustrating a manufacturing process of the droplet discharge head according to the first embodiment; FIG. 8 is a diagram (part 2) illustrating a manufacturing process of the droplet discharge head according to the first embodiment; FIG. 6 is a diagram (part 3) illustrating a manufacturing process of the droplet discharge head according to the first embodiment; FIG. 10 is a diagram illustrating a manufacturing process of the droplet discharge head according to the second embodiment. It is an external view of a droplet discharge device using a droplet discharge head. It is a figure showing an example of the main structural means of a droplet discharge apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Droplet discharge head, 10 electrode board | substrate, 11 recessed part, 12 electrodes, 12A individual electrode part, 12B lead wiring part, 12C terminal part, 13 signal wiring, 14 liquid intake port, 15 insulating film, 20 cavity board | substrate, 21 discharge Chamber, 22 Diaphragm, 23 Insulating film, 24 Sealing material, 25 Common electrode terminal, 26 Driver housing part, 30 Reservoir substrate, 31 Reservoir, 32 Supply port, 33 Nozzle communication hole, 40 Nozzle substrate, 41 Nozzle, 50 Driver IC, 51 FPC, 61 silicon substrate, 62 TEOS hard mask, 63 silicon mask, 64 mask, 100 printer, 101 drum, 102 droplet discharge head, 103 paper crimping driver, 104 feed screw, 105 belt, 106 motor, 107 print Control means, 110 Printed paper.

Claims (6)

An electrostatic actuator comprising a movable electrode and a fixed electrode formed on an electrode substrate, and driving the movable electrode by applying a voltage between the movable electrode and the fixed electrode to generate an electrostatic force. And
The electrode substrate further includes a terminal for electrically connecting to the driving device, a lead wire for electrically connecting the individual electrode and the terminal, and an insulating film for covering and insulating the plurality of lead wires. An electrostatic actuator comprising:   2. The electrostatic actuator according to claim 1, wherein the insulating film is also coated on the fixed electrode.   3. The electrostatic actuator according to claim 1, wherein the insulating film is composed of a plurality of laminated films, and the outermost film is a film having resistance to a gas by dry etching. It has the electrostatic actuator in any one of Claims 1-3,
A droplet discharge head, wherein at least a part of a discharge chamber filled with a liquid is used as the movable electrode, and droplets are discharged from a nozzle communicating with the discharge chamber by displacement of the movable electrode.   A liquid droplet ejection apparatus comprising the liquid droplet ejection head according to claim 4.   An electrostatic device comprising the electrostatic actuator according to claim 1.

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