JP2005219243A - Method for manufacturing liquid jet head and liquid jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid ejecting head manufacturing method and a liquid ejecting head capable of reliably preventing ejection failure such as nozzle clogging.
A vibration plate is formed on one surface side of a flow path forming substrate 10 made of a silicon substrate, and a portion of a vibration plate (an elastic film 50 and a portion facing a region where a communication portion 13 of the flow path forming substrate 10 is formed. Removing the insulator film 55) to form openings 50a and 55a exposing one surface of the flow path forming substrate 10, and diffusing boron into the flow path forming substrate 10 exposed in the opening 50a. Forming the boron doped layer 130, forming the piezoelectric element 300 on the diaphragm, bonding the reservoir forming substrate 30 to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side, and the flow path forming substrate Forming the pressure generating chamber 12 by wet etching from the other surface side of the substrate 10 until the boron dope layer 130 and the diaphragm are exposed, and forming the communicating portion 13 in a region facing the reservoir portion 31. And a step of removing the boron dope layer 130 by dry etching and causing the reservoir portion 31 and the communication portion 13 to communicate with each other.
[Selection] Figure 5

Description

  The present invention relates to a method for manufacturing a liquid ejecting head that ejects liquid and a liquid ejecting head, and more particularly, to a method for manufacturing an ink jet recording head that ejects ink as a liquid.

  An ink jet type in which a part of a pressure generating chamber communicating with a nozzle opening for discharging ink is constituted by a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize ink in the pressure generating chamber and discharge ink from the nozzle opening. Two types of recording heads have been put into practical use: those using a longitudinal vibration mode piezoelectric actuator that expands and contracts in the axial direction of the piezoelectric element, and those using a flexural vibration mode piezoelectric actuator.

  The former can change the volume of the pressure generation chamber by bringing the end face of the piezoelectric element into contact with the vibration plate, and it is possible to manufacture a head suitable for high-density printing, while the piezoelectric element is arranged in an array of nozzle openings. There is a problem that the manufacturing process is complicated because a difficult process of matching the pitch into a comb-like shape and an operation of positioning and fixing the cut piezoelectric element in the pressure generating chamber are necessary.

  On the other hand, the latter can flexibly vibrate, although a piezoelectric element can be built on the diaphragm by a relatively simple process of sticking a green sheet of piezoelectric material according to the shape of the pressure generation chamber and firing it. There is a problem that a certain amount of area is required for the use of, and high-density arrangement is difficult.

  On the other hand, in order to eliminate the disadvantages of the latter recording head, a uniform piezoelectric material layer is formed over the entire surface of the diaphragm by a film forming technique, and this piezoelectric material layer is shaped to correspond to the pressure generating chamber by lithography. In some cases, a high-density array is realized by forming piezoelectric elements so that each pressure generating chamber is independent.

  In addition, as such an ink jet recording head, a flow path forming substrate in which a pressure generating chamber communicating with a nozzle opening and a communicating portion communicating with the pressure generating chamber are formed, and one surface side of the flow path forming substrate And a reservoir forming substrate having a reservoir portion which is joined to a surface of the flow path forming substrate on the piezoelectric element side and forms a part of the reservoir together with the communication portion. There has been proposed a structure in which a reservoir portion and a communication portion are communicated with each other through a penetrating portion penetrating the laminated film formed on the top (see, for example, Patent Document 1). In such a method of manufacturing an ink jet recording head, the reservoir portion and the communication portion are formed by mechanically punching a portion facing the communication portion (reservoir portion) of the diaphragm and the laminated film to form a through portion. And communicate with each other.

  However, in such mechanical processing, it is difficult to remove the processing residue from the inside of the flow path forming substrate such as the pressure generation chamber, and the nozzle opening is blocked by the processing residue remaining in the flow path forming substrate, resulting in poor discharge. There is a problem that it occurs. Further, when the penetrating portion is mechanically processed, there is a problem that a crack or the like is generated around the penetrating portion. When ink is filled and discharged in the state where this crack has occurred, there is a problem in that debris will fall off from the cracked portion of the diaphragm and the nozzle opening will be blocked by this fragment, resulting in ejection failure. is there.

  Further, this publication discloses a structure in which the periphery of the penetrating portion is covered with a protective film. According to this structure, since the periphery of the through portion is not exposed to ink, the nozzle opening is blocked by a fragment generated from a crack or the like around the through portion, thereby preventing ejection failure. Can do. However, since the penetrating portion is formed by mechanically processing the diaphragm, it is impossible to prevent the machining residue during processing from remaining in the flow path forming substrate. Therefore, it cannot be prevented that the nozzle opening is blocked by the machining residue and a discharge failure occurs. Such a problem exists not only in an ink jet recording head that ejects ink, but also in a method of manufacturing another liquid ejecting head that ejects liquid other than ink.

JP 2003-159801 A (FIGS. 7-8)

  In view of such circumstances, it is an object of the present invention to provide a method of manufacturing a liquid ejecting head and a liquid ejecting head that can reliably prevent ejection failure such as nozzle clogging.

  A first aspect of the present invention that solves the above-described problem is a flow path forming substrate that includes a pressure generation chamber that is formed of a silicon substrate and communicates with a nozzle opening that ejects liquid, and a communication portion that communicates with the pressure generation chamber. A piezoelectric element that causes a pressure change in the pressure generating chamber via a vibration plate on one surface side of the flow path forming substrate, and the piezoelectric element side surface of the flow path forming substrate that is joined to the piezoelectric element side. A liquid jet head manufacturing method comprising: a reservoir forming substrate on which a reservoir portion constituting a part of a reservoir which is a common liquid chamber of each of the pressure generating chambers is formed, wherein the one surface of the flow path forming substrate The diaphragm is formed on the side, and an opening for exposing one surface of the flow path forming substrate is formed by removing the vibration plate in a portion facing the region where the communication portion of the flow path forming substrate is formed. And the opening A step of diffusing boron into the flow path forming substrate exposed inside to form a boron doped layer, a step of forming the piezoelectric element on the diaphragm, and a surface of the flow path forming substrate on the piezoelectric element side Bonding the reservoir forming substrate to the substrate, and wet etching from the other surface side of the flow path forming substrate until the boron dope layer and the diaphragm are exposed to form the pressure generating chamber and face the reservoir portion. A method of manufacturing a liquid jet head comprising: forming the communication portion in a region; and removing the boron-doped layer by dry etching to connect the reservoir portion and the communication portion. .

  In the first aspect, since the boron-doped layer is removed by dry etching, no foreign matter such as processing residue is generated unlike mechanical processing. Therefore, it is possible to reliably prevent ejection defects such as nozzle clogging caused by foreign matters remaining in the flow path forming substrate.

  According to a second aspect of the present invention, in the first aspect, the reservoir portion is provided through the reservoir forming substrate in a thickness direction, and the step of forming the pressure generating chamber is the reservoir forming substrate. In the method of manufacturing a liquid jet head, the upper surface opposite to the flow path forming substrate side is sealed with a sealing film made of an alkali-resistant material.

  In the second aspect, since the upper surface of the reservoir forming substrate is sealed with the sealing film, the etching liquid adheres to the upper surface of the reservoir forming substrate when the other surface of the flow path forming substrate is etched. It can be surely prevented.

  According to a third aspect of the invention, there is provided a liquid jet head formed by the manufacturing method according to the first or second aspect.

  In the third aspect, a highly reliable liquid ejecting head can be provided.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view showing an ink jet recording head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view and a cross-sectional view of FIG. As shown in the figure, the flow path forming substrate 10 is formed of a silicon single crystal substrate having a plane orientation (110) in this embodiment, and one surface thereof is previously formed of silicon dioxide by thermal oxidation and has a thickness of 1 to 2 μm. Although the film 50 is formed, the elastic film 50 constitutes a part of the diaphragm. A plurality of pressure generating chambers 12 are arranged in parallel in the width direction of the flow path forming substrate 10. In addition, a communication portion 13 is formed in a region outside the longitudinal direction of the pressure generation chamber 12 of the flow path forming substrate 10, and the communication portion 13 and each pressure generation chamber 12 are provided for each pressure generation chamber 12. Communication is made via a supply path 14. The communication unit 13 constitutes a part of the reservoir 100 that communicates with a reservoir unit 31 of the reservoir forming substrate 30 described later and serves as a common ink chamber for the pressure generation chambers 12. The ink supply path 14 is formed with a narrower width than the pressure generation chamber 12, and maintains a constant flow path resistance of ink flowing into the pressure generation chamber 12 from the communication portion 13.

Further, on the opening surface side of the flow path forming substrate 10, a mask film 51 used as a mask when forming the pressure generating chamber 12 is interposed, and the pressure generating chamber 12 is opposite to the ink supply path 14. A nozzle plate 20 having a nozzle opening 21 communicating in the vicinity of the end is fixed through an adhesive, a heat-welded film, or the like. The nozzle plate 20 has a thickness of, for example, 0.01 to 1 mm, a linear expansion coefficient of 300 ° C. or less, for example, 2.5 to 4.5 [× 10 ⁻⁶ / ° C.], glass ceramics, silicon It consists of a single crystal substrate or non-rust steel.

  On the other hand, as described above, the elastic film 50 having a thickness of, for example, about 1.0 μm is formed on the side opposite to the opening surface of the flow path forming substrate 10. For example, an insulator film 55 having a thickness of about 0.4 μm is formed. Further, on the insulator film 55, a lower electrode film 60 having a thickness of, for example, about 0.2 μm, a piezoelectric layer 70 having a thickness of, for example, about 1.0 μm, and a thickness of, for example, about 0 The upper electrode film 80 having a thickness of 0.05 μm is laminated by a process described later to constitute the piezoelectric element 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70, and the upper electrode film 80. In general, one electrode of the piezoelectric element 300 is used as a common electrode, and the other electrode and the piezoelectric layer 70 are patterned for each pressure generating chamber 12. In addition, here, a portion that is configured by any one of the patterned electrodes and the piezoelectric layer 70 and in which piezoelectric distortion is generated by applying a voltage to both electrodes is referred to as a piezoelectric active portion. In the present embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric element 300 and the upper electrode film 80 is used as an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for convenience of a drive circuit and wiring. In either case, a piezoelectric active part is formed for each pressure generating chamber. Further, here, the piezoelectric element 300 and the vibration plate that is displaced by driving the piezoelectric element 300 are collectively referred to as a piezoelectric actuator. In the example described above, the elastic film 50, the insulator film 55, and the lower electrode film 60 serve as a diaphragm.

Here, as a material for forming the piezoelectric layer 70, for example, a ferroelectric piezoelectric material such as lead zirconate titanate (PZT) or a metal such as niobium, nickel, magnesium, bismuth or ytterbium is added thereto. Relaxed ferroelectrics or the like are used. The composition may be appropriately selected in consideration of the characteristics, application, etc. of the piezoelectric element 300. For example, PbTiO ₃ (PT), PbZrO ₃ (PZ), Pb (Zr _x Ti _1-x ) O ₃ (PZT) ), Pb (Mg _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PMN-PT), Pb (Zn _1/3 Nb _2/3 ) O ₃ -PbTiO ₃ (PZN-PT), Pb (Ni ₁ ) _{/ 3 Nb 2/3) O 3 -PbTiO} 3 (PNN-PT), Pb (In 1/2 Nb 1/2) O 3 -PbTiO 3 (PIN-PT), Pb (Sc 1/3 Ta 1/2 _{) O 3 -PbTiO 3 (PST-} PT), Pb (Sc 1/3 Nb 1/2) O 3 -PbTiO 3 (PSN-PT), BiScO 3 -PbTiO 3 (BS-PT), BiYbO 3 -PbTiO 3 (BY PT), and the like.

  In the present embodiment, the layers constituting the piezoelectric element 300 described above, that is, the lower electrode film 60, the piezoelectric layer 70, and the upper layer are formed on the insulator film 55 and in the region facing the opening peripheral edge of the communication portion 13. A laminated film 400 that is composed of the electrode film 80 and is discontinuous with the piezoelectric element 300 is provided. As described above, in the present embodiment, the laminated film 400 is provided. However, the present invention is not limited to this, and the laminated film 400 may not be provided.

  A reservoir forming substrate 30 having a reservoir portion 31 constituting at least a part of the reservoir 100 is bonded to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side via an adhesive 35. In this embodiment, the reservoir portion 31 is formed across the reservoir forming substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12, and is communicated with the communicating portion 13 of the flow path forming substrate 10. A reservoir 100 serving as an ink chamber common to the pressure generation chamber 12 is configured.

  Further, a piezoelectric element holding portion 32 capable of securing a space that does not hinder the movement of the piezoelectric element 300 is provided in a region facing the piezoelectric element 300 of the reservoir forming substrate 30. The piezoelectric element 300 is formed in the piezoelectric element holding portion 32. Examples of the material of the reservoir forming substrate 30 include glass, ceramic material, metal, resin, and the like, and the reservoir forming substrate 30 is formed of substantially the same material as the thermal expansion coefficient of the flow path forming substrate 10. In this embodiment, the silicon single crystal substrate made of the same material as the flow path forming substrate 10 is used.

  Further, outside the piezoelectric element holding portion 32 of the reservoir forming substrate 30, the other end portion of the lead electrode 90 having one end connected to each piezoelectric element 300 described above extends to the vicinity of the end portion of the flow path forming substrate 10. It is installed. The other end of each lead electrode 90 is connected to the other end of the connection wiring 120 having one end connected to the drive IC 110 mounted on the reservoir forming substrate 30.

  Further, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the reservoir forming substrate 30. The sealing film 41 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide (PPS) film having a thickness of 6 μm). Yes. The fixing plate 42 is made of a hard material such as metal (for example, stainless steel (SUS) having a thickness of 30 μm). Since the region of the fixing plate 42 facing the reservoir 100 is an opening 43 that is completely removed in the thickness direction, one surface of the reservoir 100 is sealed only with a flexible sealing film 41. Has been.

  In such an ink jet recording head of this embodiment, ink is taken in from an external ink supply means (not shown), filled with ink from the reservoir 100 to the nozzle opening 21, and then subjected to pressure according to a recording signal from the driving IC 110. By applying a voltage between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the generation chamber 12 to bend and deform the piezoelectric element 300 and the diaphragm, the pressure in each pressure generation chamber 12 is increased. Ink is ejected from the opening 21.

Here, an example of a method for manufacturing such an ink jet recording head will be described with reference to FIGS. 3 to 5 are cross-sectional views of the pressure generating chamber 12 in the longitudinal direction. First, as shown in FIG. 3A, the flow path forming substrate 10 which is a silicon single crystal substrate is thermally oxidized in a diffusion furnace at about 1100 ° C., and an elastic film 50 and a mask film 51 are formed on the surface of the flow path forming substrate 10. A silicon dioxide film 52 is formed. Thereafter, as shown in FIG. 3B, the elastic film 50 is patterned into a predetermined shape. Specifically, the elastic film 50 is removed from the elastic film 50 in a portion of the flow path forming substrate 10 that faces the region where the communication portion 13 is formed in a process described later by wet etching. An opening 50a that exposes one surface of the film 10 is formed. Next, as shown in FIG. 3C, boron is diffused on one surface of the flow path forming substrate 10 exposed in the opening 50 a of the elastic film 50 to form a boron dope layer 130. For example, the flow path forming substrate 10 exposed between the openings 50a of the elastic film 50 by sandwiching the flow path forming substrate 10 with a plurality of boron targets in a boron diffusion furnace and diffusing boron at about 1000 ° C. to 1200 ° C. A boron doped layer 130 is formed on one side of the substrate 10. Thereby, the boron dope layer 130 can be formed in a portion facing the region where the communication portion 13 of the flow path forming substrate 10 is formed. Next, as shown in FIG. 3D, a zirconium (Zr) layer is formed on the elastic film 50 (silicon dioxide film 52), and then thermally oxidized in, for example, a diffusion furnace at 500 to 1200 ° C. to form zirconium oxide. A portion corresponding to the opening 50a of the elastic film 50 is formed by forming the insulator film 55 made of (ZrO ₂ ) and patterning the insulator film 55 through a mask pattern (not shown) made of a resist or the like, for example. An opening 55 a is formed in the insulator film 55. Thereby, one surface of the flow path forming substrate 10 is exposed through the opening 50 a of the elastic film 50 and the opening 55 a of the insulator film 55.

  Next, as shown in FIG. 4A, for example, after the lower electrode film 60 is formed by laminating platinum and iridium on the insulator film 55, the lower electrode film 60 is patterned into a predetermined shape. Next, after the piezoelectric layer 70 made of, for example, lead zirconate titanate (PZT) and the upper electrode film 80 made of, for example, iridium are formed on the entire surface of the flow path forming substrate 10, the piezoelectric layer 70 and The upper electrode film 80 is patterned in a region facing each pressure generating chamber 12 to form a piezoelectric element 300 as shown in FIG. Further, in the present embodiment, the openings of the elastic film 50 are left by leaving the respective layers constituting the piezoelectric element 300 in the regions corresponding to the opening peripheral portions of the opening 50 a of the elastic film 50 and the opening 55 a of the insulator film 55. The laminated film 400 having the opening 400a communicating with the portion 50a is formed. The laminated film 400 is patterned so as to be discontinuous with the piezoelectric element 300. Next, as shown in FIG. 4C, the lead electrode 90 is formed. Specifically, after a metal layer made of, for example, gold (Au) or the like is formed over the entire surface of the flow path forming substrate 10, the metal layer is formed through a mask pattern (not shown) made of, for example, a resist or the like. The lead electrode 90 is formed by patterning for each piezoelectric element 300. Next, as shown in FIG. 4D, the reservoir forming substrate 30 on which the reservoir portion 31 and the piezoelectric element holding portion 32 are formed is bonded to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side by an adhesive 35. To do.

  Next, as shown in FIG. 5A, for example, the elastic film 50 and the boron doped layer 130 are exposed from the other surface side of the flow path forming substrate 10 through the mask film 51 patterned into a predetermined shape. In the embodiment, the pressure generation chamber 12, the ink supply path 14, and the communication portion 13 are formed by anisotropic etching (wet etching) using a potassium hydroxide aqueous solution. At this time, the elastic film 50 and the boron doped layer 130 are hardly etched because the etching rate is extremely small as compared with the flow path forming substrate 10 made of a silicon single crystal substrate. That is, the etching of the flow path forming substrate 10 stops at the elastic film 50 and the boron doped layer 130. Further, in the present embodiment, the step of forming the pressure generating chamber 12 and the like is performed on the upper surface of the reservoir forming substrate 30 on the side opposite to the flow path forming substrate 10 side by using a material having alkali resistance, for example, PPS ( The sealing was performed with a sealing film made of polyphenylene sulfide), PPTA (polyparaphenylene terephthalamide) or the like. As a result, it is possible to reliably prevent the etching liquid from adhering to the wiring or the like (not shown) provided on the surface of the reservoir forming substrate 30. Further, the etching solution enters the reservoir portion 31 to etch the reservoir forming substrate 30, or the inner peripheral surface of the opening 400 a of the laminated film 400 or the reservoir forming substrate 30 adjacent to the adhesive 35 is laminated. It is possible to reliably prevent the adhesion interface with the film 400 from being damaged.

  Next, as shown in FIG. 5B, the boron dope layer 130 that separates the communication portion 13 of the flow path forming substrate 10 and the reservoir portion 31 of the reservoir forming substrate 30 is removed by dry etching. As a result, the communication part 13 and the reservoir part 31 communicate with each other via the opening part 50a of the elastic film 50 and the opening part 50a of the insulator film 55, and the reservoir 100 constituted by the communication part 13 and the reservoir part 31 is formed. Is done. Here, in this embodiment, since the opening 50a of the elastic film 50 and the opening 55a of the insulator film 55 are formed by the above-described process, the communication portion 13 of the flow path forming substrate 10 and the reservoir forming substrate 30 are formed. Only the boron-doped layer 130 separates the reservoir portion 31 from the other. For this reason, the communication part 13 and the reservoir | reserver part 31 can be communicated comparatively easily and reliably only by removing the boron dope layer 130 by dry etching. Specifically, the elastic film 50 (silicon dioxide film 52) takes a much longer time to penetrate by dry etching than the boron-doped layer 130. For this reason, in the present embodiment, such an elastic film 50 is previously removed by wet etching, and after the pressure generating chamber 12 and the like are formed, the boron dope layer 130 is removed by dry etching. Can be greatly shortened. Further, since the boron dope layer 130 is removed by dry etching in this way, foreign matter such as processing residue is not generated unlike the conventional mechanical processing and remains in the flow path forming substrate 10. It is possible to reliably prevent ejection defects that occur due to clogging of the machining residue into the nozzle opening 21.

  Thereafter, the nozzle plate 20 is bonded to the flow path forming substrate 10 via the mask film 51, the driving IC 110 is mounted on the reservoir forming substrate 30, and the compliance substrate 40 is bonded. Furthermore, by connecting the driving IC 110 mounted on the reservoir forming substrate 30 and the lead electrode 90 by the connection wiring 120 by wire bonding, the ink jet recording head of this embodiment is obtained.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, this invention is not limited to Embodiment 1 mentioned above. For example, in Embodiment 1 described above, after forming the opening 50a in the elastic film 50, the boron doped layer 130 is formed on one surface of the flow path forming substrate 10 exposed through the opening 50a. However, the present invention is not limited to this, and by forming an insulating film on the elastic film and removing the portion of the elastic film and the insulating film facing the region where the communication portion of the flow path forming substrate is formed, the flow path is formed. After forming an opening exposing one surface of the substrate in the elastic film and the insulator film, a boron doped layer may be formed on one surface of the flow path forming substrate exposed through each opening. .

  Further, in the first embodiment described above, the reservoir portion 31 has a structure that penetrates the reservoir forming substrate 30, but the present invention is not limited to this, and a structure in which the reservoir portion does not penetrate may be employed. Even when the reservoir forming substrate having such a reservoir portion is made of a silicon substrate, in the step of forming the pressure generating chamber or the like in the flow path forming substrate, the etching stops at the boron dope layer. Can be reliably prevented from entering and etching the inside of the reservoir.

  In the first embodiment described above, the ink jet recording head manufacturing method has been described as an example of the liquid jet head manufacturing method of the present invention. However, the basic configuration of the liquid jet head is limited to the above-described configuration. It is not a thing. The present invention is intended for a wide range of liquid ejecting heads, and can of course be applied to a method of manufacturing a liquid ejecting head that ejects liquid other than ink. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (surface emitting displays). Examples thereof include an electrode material ejection head used for electrode formation, a bioorganic matter ejection head used for biochip production, and the like.

FIG. 3 is an exploded perspective view of the recording head according to the first embodiment. 2A and 2B are a plan view and a cross-sectional view of the recording head according to the first embodiment. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG. 5 is a cross-sectional view illustrating a manufacturing process of the recording head according to Embodiment 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flow path formation board | substrate, 12 Pressure generation chamber, 20 Nozzle plate, 21 Nozzle opening, 30 Reservoir formation board | substrate, 31 Reservoir part, 32 Piezoelectric element holding | maintenance part, 35 Adhesive layer, 40 Compliance board | substrate, 50 Elastic film, 50a Opening part 55 Insulator film, 60 Lower electrode film, 70 Piezoelectric layer, 80 Upper electrode film, 100 Reservoir, 110 Drive IC, 120 Connection wiring, 130 Boron doped layer, 300 Piezoelectric element, 400 Multilayer film

Claims (3)

A flow path forming substrate formed of a pressure generating chamber that is made of a silicon substrate and communicates with a nozzle opening that ejects liquid, and a communication portion that communicates with the pressure generating chamber, and a diaphragm on one surface side of the flow path forming substrate A piezoelectric element that causes a pressure change in the pressure generating chamber, and a reservoir that is joined to the surface of the flow path forming substrate on the piezoelectric element side and that is a common liquid chamber of the pressure generating chambers together with the communicating portion. A liquid ejecting head manufacturing method comprising a reservoir forming substrate on which a reservoir portion constituting a part is formed,
The vibration plate is formed on one side of the flow path forming substrate, and the vibration plate is removed from a portion of the flow path forming substrate facing the region where the communication portion is formed. Forming an opening that exposes the surface, diffusing boron into the flow path forming substrate exposed in the opening to form a boron-doped layer, and forming the piezoelectric element on the diaphragm Bonding the reservoir forming substrate to the surface of the flow path forming substrate on the piezoelectric element side, and performing wet etching until the boron dope layer and the diaphragm are exposed from the other surface side of the flow path forming substrate. Forming the pressure generating chamber and forming the communicating portion in a region facing the reservoir portion; removing the boron-doped layer by dry etching to communicate with the reservoir portion; The method of manufacturing a liquid jet head, characterized by comprising the steps of communicating and. 2. The reservoir portion according to claim 1, wherein the reservoir portion is provided through the reservoir forming substrate in a thickness direction, and the step of forming the pressure generating chamber is opposite to the flow path forming substrate side of the reservoir forming substrate. A method for producing a liquid ejecting head, comprising performing the process in a state where the upper surface on the side is sealed with a sealing film made of an alkali-resistant material. A liquid jet head formed by the manufacturing method according to claim 1.

Images