JP2005088441A - Liquid injection head and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid injection head and a liquid injection device that can prevent a decrease in the displacement of a vibrating plate and can prevent a breakage of a piezoelectric element attributed to an external environment. <P>SOLUTION: The liquid injection head is structured so as to form a lower electrode 60 of the area facing a pressure generation chamber 12 as one smaller in width than the pressure generation chamber 12, cover the top face and end of the lower electrode 60 of the area corresponding to the pressure generation chamber 12 with a piezoelectric body layer 70, and cover the top face and end of the piezoelectric body layer 70 with an upper electrode 80 provided on the piezoelectric body layer 70. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus, and in particular, a part of a pressure generating chamber communicating with a nozzle opening for ejecting ink droplets is configured by a vibration plate, and a piezoelectric element is formed on the surface of the vibration plate. The present invention relates to an ink jet recording head and an ink jet recording apparatus that eject ink droplets by displacement of a piezoelectric element.

  A part of the pressure generation chamber communicating with the nozzle opening for discharging ink droplets is constituted by a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize the ink in the pressure generation chamber to discharge ink droplets from the nozzle opening. Two types of ink jet recording heads have been put into practical use: those using a longitudinal vibration mode piezoelectric actuator that extends 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, the piezoelectric element is formed so as to be independent for each pressure generating chamber. Further, such a piezoelectric element has a problem that it is easily destroyed due to an external environment such as moisture. In order to solve this problem, for example, there is one in which a protective film made of an insulator is provided on the outer peripheral surface of a piezoelectric element (see, for example, Patent Document 1).

  However, if the piezoelectric element is covered with an insulating film in this way, the displacement of the diaphragm due to the driving of the piezoelectric element is reduced even if the piezoelectric element can be prevented from being damaged due to the external environment. There is. Further, Patent Document 1 discloses a structure in which the thickness of the protective film is partially reduced to suppress a decrease in the amount of displacement of the diaphragm. Certainly, when this structure is compared with a piezoelectric element whose surface is covered with a uniform protective film, a decrease in the amount of displacement of the diaphragm is suppressed, but a structure without a protective film is provided. In comparison, it cannot be said that the decrease in displacement is sufficiently suppressed. Such a problem exists not only in an ink jet recording head that ejects ink droplets, but also in other liquid ejecting heads that eject droplets other than ink.

JP 2001-260357 A (Claims)

  In view of such circumstances, it is an object of the present invention to provide a liquid ejecting head and a liquid ejecting apparatus that can prevent a decrease in the amount of displacement of a diaphragm and prevent breakage due to an external environment of a piezoelectric element.

According to a first aspect of the present invention for solving the above problems, a flow path forming substrate in which pressure generation chambers communicating with nozzle openings for discharging droplets are formed, and a vibration plate on one side of the flow path forming substrate are provided. A liquid ejecting head comprising a lower electrode, a piezoelectric layer, and an upper electrode provided via the upper electrode, wherein the lower electrode in a region facing the pressure generating chamber is narrower than the pressure generating chamber. The upper surface and the end surface of the lower electrode in the region corresponding to the pressure generating chamber are covered with the piezoelectric layer, and the upper surface and the end surface of the piezoelectric layer are provided on the piezoelectric layer. The liquid ejecting head is covered with the upper electrode formed.
In the first aspect, since the piezoelectric layer is covered with the upper electrode, it is possible to prevent the piezoelectric element (piezoelectric layer) from being damaged due to moisture (humidity). In addition, since it is not necessary to provide a protective film separately from the piezoelectric element, a decrease in the piezoelectric element and displacement can be suppressed.

According to a second aspect of the present invention, in the first aspect, an insulating film is provided on a part of the lower electrode in a region corresponding to the vicinity of the end in the longitudinal direction of the pressure generating chamber, An end of the lower electrode is provided on the insulating film.
In the second aspect, the surface of the piezoelectric layer can be easily covered with the upper electrode without short-circuiting the lower electrode and the upper electrode.

According to a third aspect of the present invention, in the first aspect, the lower electrode is formed in a region facing each pressure generating chamber, and an upper surface and an end surface thereof are covered with the piezoelectric layer, and the lower electrode is In the liquid jet head, the connection wiring provided between the plurality of insulating films constituting the diaphragm is connected to the surface of the lower electrode opposite to the piezoelectric layer.
In the third aspect, the surface of the piezoelectric layer can be covered with the upper electrode without providing a layer different from the piezoelectric element on the diaphragm.

According to a fourth aspect of the present invention, in the liquid jet head according to any one of the first to third aspects, the upper electrode is continuously provided in a region facing the plurality of piezoelectric elements. .
In the fourth aspect, the upper electrode can be easily patterned, and the manufacturing process can be simplified.

A fifth aspect of the present invention is a liquid ejecting apparatus including the liquid ejecting head according to any one of the first to fourth aspects.
In the fifth aspect, it is possible to realize a liquid ejecting apparatus with improved durability and reliability.

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 made of a silicon single crystal substrate having a plane orientation (110) in the present embodiment, and one surface thereof is made of silicon dioxide previously formed by thermal oxidation. A 2 μm elastic film 50 is formed. 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 part 13 constitutes a part of a reservoir that communicates with a reservoir part of a protective substrate, which will be described later, and serves as a common ink chamber for the pressure generating 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, an insulating film 51 used as a mask when forming the pressure generating chambers 12 is interposed on the side opposite to the ink supply path 14 of each pressure generating chamber 12. 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 this embodiment, the lower electrode film 60 is a common electrode of the piezoelectric element 300, and the upper electrode film 80 is an individual electrode of the piezoelectric element 300. However, there is no problem even if this is reversed for the convenience of the 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.

  Here, the structure of the piezoelectric element 300 according to the present embodiment will be described in detail. As shown in FIG. 3, the lower electrode film 60 constituting the piezoelectric element 300 is provided with a width narrower than the width of the pressure generation chamber 12 in each region facing each pressure generation chamber 12. The lower electrode film 60 extends from one longitudinal end of each pressure generating chamber 12 to the peripheral wall and is connected on the peripheral wall to be a common electrode common to the piezoelectric elements 300. In the present embodiment, the end portion of the lower electrode film 60 on the other end side in the longitudinal direction of the pressure generation chamber 12 is located in a region facing the pressure generation chamber 12.

Further, an insulating film 65 made of, for example, silicon dioxide (SiO ₂ ) is provided on the lower electrode film 60 in a region corresponding to one longitudinal end of the pressure generating chamber 12. In this embodiment, the insulating film 65 is provided on the lower electrode film 60 in a region facing each pressure generating chamber 12, but on the lower electrode film 60 in a region facing the plurality of pressure generating chambers 12. May be provided continuously.

  In the present embodiment, the piezoelectric layer 70 is provided in a region facing the pressure generation chamber 12 with a width wider than the width of the lower electrode film 60. The end of the piezoelectric layer 70 on one end side of the pressure generation chamber 12 is located on the insulating film 65, and the end on the other end side of the pressure generation chamber 12 is more than the end of the lower electrode film 60. Located on the outside. That is, the piezoelectric layer 70 is provided so as to completely cover the upper surface and the end surface of the lower electrode film 60 in a region corresponding to the pressure generation chamber 12.

  In the present embodiment, the upper electrode film 80 has a width wider than the width of the piezoelectric layer 70 and is independently provided in a region facing each pressure generating chamber 12. And it is extended from the longitudinal direction other end part side of the pressure generation chamber 12 to the surrounding wall. That is, the upper electrode film 80 is provided so as to completely cover the upper surface and the end surface of the piezoelectric layer 70, and also serves as a protective film that prevents the penetration of moisture (humidity) in the atmosphere into the piezoelectric layer 70. . For example, in the present embodiment, since the upper electrode film 80 is made of a metal such as iridium (Ir), moisture (humidity) in the atmosphere permeates the piezoelectric layer 70 by completely covering the surface of the piezoelectric layer 70. Can be prevented. Accordingly, it is possible to prevent the piezoelectric element 300 (piezoelectric layer 70) from being damaged due to moisture (humidity), and the durability of the piezoelectric element 300 can be significantly improved.

  Further, since the upper electrode film 80 is provided so as to cover the surface of the piezoelectric layer 70, it is also formed on the diaphragm (insulator film 55), but the thickness of the upper electrode film 80 is Since it is very thin, about 0.05 μm, it does not disturb the displacement of the diaphragm. Further, the upper electrode film 80 is one electrode of the piezoelectric element 300, and the thickness of the piezoelectric element 300 itself does not change, so that the displacement characteristics of the piezoelectric element 300 are not deteriorated. Therefore, even with the configuration of the present invention, the displacement amount of the piezoelectric element 300 and the diaphragm does not decrease, and good ink ejection characteristics can be obtained.

  A protective substrate 30 having a piezoelectric element holding portion 31 that can secure a space that does not hinder the movement of the region facing the piezoelectric element 300 is bonded to the surface of the flow path forming substrate 10 on the piezoelectric element 300 side. It is joined via the agent 35. Since the piezoelectric element 300 is formed in the piezoelectric element holding part 31, it is protected in a state hardly affected by the external environment. In addition, the protection substrate 30 is provided with a reservoir portion 32 in a region corresponding to the communication portion 13 of the flow path forming substrate 10. In this embodiment, the reservoir portion 32 is provided along the direction in which the pressure generating chambers 12 are arranged so as to penetrate the protective substrate 30 in the thickness direction, and as described above, the communication portion of the flow path forming substrate 10. The reservoir 100 is connected to the pressure generation chamber 12 and serves as a common ink chamber for the pressure generation chambers 12.

Further, a through hole 33 that penetrates the protective substrate 30 in the thickness direction is provided in a region between the piezoelectric element holding portion 31 and the reservoir portion 32 of the protective substrate 30, and the lower electrode film 60 and the upper electrode film 80 are formed. An end portion is exposed in the through hole 33. Although not shown, the lower electrode film 60 and the upper electrode film 80 are connected to a driving IC or the like for driving the piezoelectric element 300 by connection wiring extending in the through hole 33.
In addition, examples of the material of the protective substrate 30 include glass, ceramic material, metal, resin, and the like, but it is more preferable that the material is substantially the same 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.

  On the protective substrate 30, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is further bonded. 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), and one surface of the reservoir portion 32 is sealed by the sealing film 41. 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 in accordance with a recording signal from a drive IC (not shown). Then, a voltage is applied between each of the lower electrode film 60 and the upper electrode film 80 corresponding to the pressure generation chamber 12 to bend and deform the elastic film 50, the insulator film 55, the lower electrode film 60, and the piezoelectric layer 70. As a result, the pressure in each pressure generating chamber 12 increases and ink droplets are ejected from the nozzle openings 21.

Here, a method of manufacturing such an ink jet recording head will be described with reference to FIGS. 4 and 5 are cross-sectional views of the pressure generation chamber 12 in the longitudinal direction. First, as shown in FIG. 4A, 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 the elastic film 50 and the mask film 51 are formed on the surface of the flow path forming substrate 10. A silicon dioxide film 52 is formed. Next, as shown in FIG. 4B, a zirconium (Zr) layer is formed on the elastic film 50 (silicon dioxide film 52), and then thermally oxidized in a diffusion furnace at 500 to 1200 ° C., for example, to form zirconium oxide ( An insulator film 55 made of ZrO ₂ ) is formed. Next, as shown in FIG. 4C, 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, as shown in FIG. 4D, an insulating film 65 made of silicon dioxide is formed on the entire surface of the flow path forming substrate 10 by, for example, CVD or sputtering, and then etched through a mask having a predetermined shape. Thus, the insulating film 65 is formed on each lower electrode film 60 in a region corresponding to the end portion on the one end portion side of the pressure generating chamber 12. Next, as shown in FIG. 5A, after the piezoelectric layer 70 is formed on the entire surface of the flow path forming substrate 10, the surface of the lower electrode film 60 is covered in a region facing each pressure generating chamber 12. Pattern. The piezoelectric layer 70 preferably has crystals oriented. For example, in the present embodiment, a so-called sol-gel method is obtained in which a so-called sol in which a metal organic material is dissolved and dispersed in a catalyst is applied and dried to be gelled, and further baked at a high temperature to obtain a piezoelectric layer 70 made of a metal oxide. Thus, the piezoelectric layer 70 in which the crystals are oriented is obtained. As a material of the piezoelectric layer 70, a lead zirconate titanate-based material is suitable when used for an ink jet recording head. In addition, the film-forming method of this piezoelectric material layer 70 is not specifically limited, For example, you may form by sputtering method.

Further, after forming a lead zirconate titanate precursor film by a sol-gel method or a sputtering method, a method of crystal growth at a low temperature by a high pressure treatment method in an alkaline aqueous solution may be used. In any case, the piezoelectric layer 70 thus formed has crystals preferentially oriented unlike the bulk piezoelectric body, and in this embodiment, the piezoelectric layer 70 is formed in a columnar shape. Has been. Note that the preferential orientation refers to a state in which the orientation direction of the crystal is not disordered and a specific crystal plane is oriented in a substantially constant direction. A columnar thin film refers to a state in which substantially cylindrical crystals are aggregated over the surface direction with the central axis substantially coincided with the thickness direction to form a thin film. Of course, it may be a thin film formed of preferentially oriented granular crystals. Note that the thickness of the piezoelectric layer manufactured in this way in the thin film process is generally 0.2 to 5 μm.
Next, as shown in FIG. 5B, for example, after the upper electrode film 80 made of iridium is formed on the entire surface of the flow path forming substrate 10, the piezoelectric layer 70 is formed in each region corresponding to each pressure generation chamber 12. The piezoelectric element 300 is formed by patterning with a size that covers the surface.

Next, as shown in FIG. 5C, the protective substrate 30 is bonded to the piezoelectric element 300 side of the flow path forming substrate 10 via an adhesive layer 35 made of a predetermined adhesive, and then patterned into a predetermined shape. The pressure generating chamber 12 and the like are formed by anisotropically etching the flow path forming substrate 10 through the mask film 51. In practice, a large number of chips are simultaneously formed on a single wafer by the above-described series of film formation and anisotropic etching, and after the process is completed, a single chip-sized flow path is formed as shown in FIG. Divide each substrate 10.
Thereafter, the nozzle plate 20 is bonded to the flow path forming substrate 10 through the mask film 51 and the compliance substrate 40 is bonded to the protective substrate 30 to obtain the ink jet recording head of this embodiment.

(Embodiment 2)
6A and 6B are a plan view and a cross-sectional view of the ink jet recording head according to the second embodiment. As shown in FIG. 6, in the present embodiment, the lower electrode film 60 is formed in a region facing each pressure generating chamber 12. The surface of the lower electrode film 60, that is, the upper surface and the end surface are completely covered with the piezoelectric layer 70, and the surface of the piezoelectric layer 70 is completely covered with the upper electrode film 80.

Further, a plurality of insulating films constituting the diaphragm, that is, between the elastic film 50 and the insulating film 55 are connected to the lower electrode film 60 through contact portions 131 provided on the insulating film 55. Connection wiring 130 is provided. Specifically, the second elastic film 53 is provided between the elastic film 50 and the insulator film 55, and the connection wiring 130 is formed in the space from which the second elastic film 53 is removed. And the connection wiring 130 is extended from the area | region facing each pressure generation chamber 12 to the area | region facing the peripheral wall of the longitudinal direction one end part side of the pressure generation chamber 12, and is each connected in the area | region facing a peripheral wall. That is, in this embodiment, the lower electrode film 60 and the connection wiring 130 form a common electrode for each piezoelectric element 300. Of course, the connection wiring 130 may be provided continuously in the column direction of the pressure generating chambers 12.
Even in such a configuration, since the surface of the piezoelectric layer 70 can be completely covered by the upper electrode film 80, similarly to the first embodiment, it is possible to prevent the displacement of the piezoelectric element 300 and the diaphragm and prevent moisture ( The destruction of the piezoelectric element 300 due to moisture) can be prevented.

In addition, although the formation method of such a connection wiring 130 and a diaphragm is not specifically limited, In this embodiment, it forms in the following processes. That is, first, as shown in FIG. 7A, a second elastic film 53 made of, for example, silicon dioxide (SiO ₂ ) is formed on the elastic film 50 (52) formed on the flow path forming substrate 10. Form. Then, the second elastic film 53 is patterned into a predetermined shape. That is, the concave portion 54 is formed by removing the second elastic film 53 in the region where the connection wiring 130 is to be formed. Next, as shown in FIG. 7B, the concave portion 54 formed in the second elastic film 53 is filled with a conductive material such as a high melting point metal to form the connection wiring 130, and the surface is formed, for example, Planarization is performed by a CMP (Chemical Mechanical Polishing) method. Next, as illustrated in FIG. 7C, after the insulator film 55 is formed on the entire surface of the flow path forming substrate 10, a connection hole 56 is formed in a region facing the connection wiring 130 of the insulator film 55. Then, as shown in FIG. 7D, the contact hole 131 with the lower electrode of the connection wiring 130 is formed by further filling the connection hole 56 with the conductive material and flattening the surface.

(Other embodiments)
As mentioned above, although each embodiment of this invention was described, this invention is not limited to embodiment mentioned above. For example, in the above-described embodiment, the lower electrode film 60 is a common electrode common to the piezoelectric elements 300. However, the present invention is not limited to this, and the upper electrode film 80 may be a common electrode. . In this case, the upper electrode film 80 may be continuously provided in a region facing the plurality of pressure generating chambers 12 (piezoelectric elements 300). Thereby, the patterning of the upper electrode film 80 becomes easy and the manufacturing efficiency can be improved.

  The ink jet recording head according to the above-described embodiment constitutes a part of a recording head unit including an ink flow path communicating with an ink cartridge or the like, and is mounted on the ink jet recording apparatus. FIG. 8 is a schematic view showing an example of the ink jet recording apparatus. As shown in FIG. 8, in the recording head units 1A and 1B having the ink jet recording head, cartridges 2A and 2B constituting ink supply means are detachably provided, and a carriage 3 on which the recording head units 1A and 1B are mounted. Is provided on a carriage shaft 5 attached to the apparatus body 4 so as to be movable in the axial direction. The recording head units 1A and 1B, for example, are configured to eject a black ink composition and a color ink composition, respectively. The driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and timing belt 7 (not shown), so that the carriage 3 on which the recording head units 1A and 1B are mounted is moved along the carriage shaft 5. The On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a paper feed roller (not shown), is conveyed on the platen 8. It is like that.

  In the above-described embodiment, the ink jet recording head has been described as an example of the liquid ejecting head of the present invention. However, the basic configuration of the liquid ejecting head is not limited to the above-described configuration. The present invention covers a wide range of liquid ejecting heads, and can naturally be applied to those ejecting liquids 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. 2A and 2B are a plan view and a cross-sectional view illustrating a main part of the recording head according to Embodiment 1. 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. 6 is a cross-sectional view of a recording head according to Embodiment 2. FIG. 6 is a cross-sectional view illustrating a manufacturing process of a recording head according to Embodiment 2. FIG. 1 is a schematic diagram of a recording apparatus according to an embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flow path formation board | substrate, 12 Pressure generation chamber, 20 Nozzle plate, 21 Nozzle opening, 30 Protection board, 31 Piezoelectric element holding | maintenance part, 32 Reservoir part, 33 Through hole, 40 Compliance board | substrate, 50 Elastic film, 53 2nd elasticity Film 55 Insulator film, 60 Lower electrode film, 70 Piezoelectric film, 80 Upper electrode film, 100 Reservoir, 130 Connection wiring, 131 Contact part, 300 Piezoelectric element

Claims (5)

A flow path forming substrate in which pressure generating chambers communicating with nozzle openings for discharging droplets are formed, and a lower electrode, a piezoelectric layer, and an upper electrode provided on one surface side of the flow path forming substrate via a vibration plate A liquid ejecting head comprising a piezoelectric element comprising:
The lower electrode in the region facing the pressure generating chamber is formed with a width narrower than that of the pressure generating chamber, and the upper surface and the end surface of the lower electrode in the region corresponding to the pressure generating chamber are covered with the piezoelectric layer. And a top surface and an end surface of the piezoelectric layer are covered with the upper electrode provided on the piezoelectric layer. 2. The insulating film according to claim 1, wherein an insulating film is provided on a part of the lower electrode in a region corresponding to the vicinity of an end in the longitudinal direction of the pressure generating chamber, and an end of the piezoelectric layer on the lower electrode is the insulating layer. A liquid ejecting head, wherein the liquid ejecting head is provided on a film. 2. The lower electrode according to claim 1, wherein the lower electrode is formed in a region facing each pressure generating chamber, and an upper surface and an end surface thereof are covered with the piezoelectric layer, and the lower electrode includes a plurality of insulations constituting the diaphragm. A liquid ejecting head, wherein a connection wiring provided between the films is connected to a surface of the lower electrode opposite to the piezoelectric layer. The liquid ejecting head according to claim 1, wherein the upper electrode is continuously provided in a region facing the plurality of piezoelectric elements. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.

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