JP5447786B2 - Liquid ejecting head, liquid ejecting apparatus, and actuator device - Google Patents

Description

  The present invention relates to a liquid ejecting head, a liquid ejecting apparatus, and an actuator device.

  A piezoelectric element used for a liquid ejecting head or the like is configured by sandwiching a piezoelectric layer made of a piezoelectric material exhibiting an electromechanical conversion function between two electrodes. As a typical example of the liquid ejecting head, for example, a part of the pressure generating chamber communicating with the nozzle opening for ejecting ink droplets is configured by a diaphragm, and the diaphragm is deformed by a piezoelectric element to There are ink jet recording heads that pressurize ink and eject ink droplets from nozzle openings.

  As a piezoelectric element mounted on an ink jet recording head, for example, a uniform piezoelectric material layer is formed over the entire surface of the vibration plate by a film forming technique, and this piezoelectric material layer corresponds to a pressure generation chamber by a lithography method. There is one in which a piezoelectric element is formed so as to be separated into shapes and independent for each pressure generation chamber (see, for example, Patent Document 1).

  In addition, there is a piezoelectric element in which a concave portion is provided in a part of the diaphragm facing the piezoelectric element to improve the deformation amount and durability of the diaphragm (see, for example, Patent Document 2).

JP 2003-163387 A JP 2000-006398 A

  However, when the piezoelectric element is driven, stress concentrates near both ends in the width direction of the piezoelectric element, and the electrode and the diaphragm constituting the piezoelectric element are broken due to cracks and the durability is lowered. There's a problem.

  Such a problem is not limited to a liquid jet head typified by an ink jet recording head, and similarly exists in an actuator device mounted in another device.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid ejecting head, a liquid ejecting apparatus, and an actuator device with improved durability.

An aspect of the present invention that solves the above problems includes a flow path forming substrate in which a plurality of pressure generating chambers communicating with a nozzle opening for ejecting a liquid are arranged in parallel, a first electrode, and a piezoelectric body above the flow path forming substrate. A piezoelectric element comprising a layer and a second electrode, wherein the piezoelectric layer has a plurality of active portions sandwiched between the first electrode and the second electrode, and the first electrode includes a plurality of the first electrodes A thickness of a region other than the end of the first region and the thickness of the first electrode are formed at the end of the first region opposite to the active portion of the first electrode. A thick film portion thicker than the thickness of the second region between the active portions is provided, and the thick film portion is provided on the piezoelectric layer side of the first electrode and protrudes to the piezoelectric layer side. The liquid jet head is characterized by the following.

  In this aspect, since the thick film portion is provided at the end portion of the first region where the stress is concentrated, the rigidity of the first electrode is increased and the driving durability can be improved. That is, there is no possibility that the first electrode constituting the piezoelectric element is broken even if the driving of the piezoelectric element is repeated.

  Here, the piezoelectric layer is individually formed for each pressure generating chamber, and the width of the active part in the juxtaposed direction of the pressure generating chamber is substantially the same as the width of the piezoelectric layer in the juxtaposed direction. The thick film portion is preferably formed at an end portion of the first region in the juxtaposed direction. According to this, it is possible to reliably prevent stress concentrated in the vicinity of both end portions in the width direction of the piezoelectric element.

  Further, the piezoelectric layer has a width wider than the width of the active part in the juxtaposed direction and is individually formed for each pressure generating chamber, and the thick film part is formed in the juxtaposed direction in the juxtaposed direction. It is preferable to extend from the end of one region to the end of the piezoelectric layer. According to this, in the region facing the end portion of the piezoelectric layer of the first electrode, the rigidity against the stress applied to the region is increased, and the driving durability can be further improved.

The first electrode preferably has an iridium oxide layer formed continuously from the iridium oxide on the entire surface of the piezoelectric layer side. According to this, the rigidity of the first electrode can be further increased by the iridium oxide layer, and destruction of the first electrode can be prevented more reliably.

  According to another aspect of the invention, there is provided a liquid ejecting apparatus including the liquid ejecting head according to the above aspect. In this aspect, a liquid ejecting apparatus with improved durability and reliability can be realized.

According to another aspect of the present invention, a piezoelectric element including a first electrode, a piezoelectric layer, and a second electrode is provided, and the piezoelectric layer includes a plurality of sandwiched between the first electrode and the second electrode. An active portion, and the first electrode is formed across the plurality of active portions, and an end of the first region is formed at an end of the first region corresponding to the active portion of the first electrode. A thick film portion thicker than the thickness of the region other than the portion and the thickness of the second region between the active portions of the first electrode is provided, and the thick film portion is provided on the piezoelectric layer side of the first electrode. It is provided in the actuator device characterized by projecting to the piezoelectric layer side .

  In this aspect, since the thick film portion is provided at the end portion of the first region where the stress is concentrated, the rigidity of the first electrode is increased and the driving durability can be improved.

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. FIG. 3 is 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. 1 is a perspective view illustrating an outline of a recording apparatus according to a first embodiment. 6 is a cross-sectional view of a recording head according to Embodiment 2. FIG.

<Embodiment 1>
FIG. 1 is an exploded perspective view showing a schematic configuration of an ink jet recording head which is an example of a liquid jet head according to Embodiment 1 of the present invention. FIG. 2 is a plan view of a flow path forming substrate and its AA. 'Is a sectional view, and FIG. 3 is a sectional view taken along the line BB ′ of FIG.

  As shown in FIG. 1, the flow path forming substrate 10 is made of a silicon single crystal substrate in this embodiment, and an elastic film 50 made of an oxide film is formed on one surface thereof.

  In the flow path forming substrate 10, a plurality of pressure generation chambers 12 are arranged in the width direction (parallel direction). 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 and a communication path 15. The communication part 13 communicates with a reservoir part 32 of a protective substrate, which will be described later, and constitutes a part of the reservoir 100 that 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. In this embodiment, the ink supply path 14 is formed by narrowing the width of the flow path from both sides. However, the ink supply path may be formed by narrowing the width of the flow path from one side. Further, the ink supply path may be formed by narrowing from the thickness direction instead of narrowing the width of the flow path.

  Further, on the opening surface side of the flow path forming substrate 10, a nozzle plate 20 having a nozzle opening 21 communicating with the vicinity of the end of each pressure generating chamber 12 on the side opposite to the ink supply path 14 is provided with an adhesive. Or a heat-welded film or the like. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, or stainless steel.

  On the other hand, the elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10 as described above, and the insulator film 55 is formed on the elastic film 50. Further, the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are laminated and formed on the insulator film 55 by a process that will be described later to form a piezoelectric element 300, and a plurality of piezoelectric elements 300 are formed. A plurality of the piezoelectric elements 300 are arranged in parallel in the width direction.

  Here, as shown in FIGS. 2 and 3, the piezoelectric element 300 refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. The first electrode 60 is continuously formed over the plurality of piezoelectric elements 300 and serves as a common electrode for the plurality of piezoelectric elements 300, and the second electrode 80 and the piezoelectric layer 70 are provided for each pressure generation chamber 12. It is formed by patterning. A portion of the piezoelectric layer 70 sandwiched between the first electrode 60 and the second electrode 80 is referred to as an active portion 320. The active portion 320 is a portion where piezoelectric strain is generated by applying a voltage to the first electrode 60 and the second electrode 80, and the first electrode 60, the insulator film 55, and the elastic film 50 (vibrating plate) are generated by the piezoelectric strain. Bends in the width direction of the piezoelectric element 300. Further, the end faces of the piezoelectric layers 70 in the juxtaposed direction of the pressure generating chambers 12 are formed substantially vertically, and the width of the piezoelectric layers 70 in the juxtaposed direction and the width of the active portion 320 are substantially the same. ing.

  The piezoelectric layer 70 is made of a piezoelectric material that is formed on the first electrode 60 and has an electromechanical conversion effect, and in particular, a ferroelectric material having a perovskite structure among the piezoelectric materials. The piezoelectric layer 70 is preferably a crystal film having a perovskite structure. For example, a ferroelectric material such as lead zirconate titanate (PZT) or a metal oxide such as niobium oxide, nickel oxide, or magnesium oxide is used. Those to which is added are suitable.

  In the present embodiment, by providing the longitudinal end portion of the pressure generation chamber 12 of the first electrode 60 in a region facing the pressure generation chamber 12, the active portion 320 serving as a substantial drive portion of the piezoelectric element 300. The end portion (length) in the longitudinal direction is defined. Further, by providing an end of the second electrode 80 in the short direction of the pressure generating chamber 12 in a region opposite to the pressure generating chamber 12, the end (width) of the active portion 320 in the short direction is defined. ing. That is, the active part 320 is provided only in a region facing the pressure generation chamber 12 by the patterned first electrode 60 and second electrode 80.

  Here, a device for providing the piezoelectric element 300 on a predetermined substrate and driving the piezoelectric element 300 is referred to as an actuator device. In the present embodiment, the elastic film 50, the insulator film 55, and the first electrode 60 function as a diaphragm, but of course not limited to this, for example, without providing the elastic film 50 and the insulator film 55. Only the first electrode 60 may act as a diaphragm.

  The first electrode 60 includes a platinum layer 61 made of platinum provided on the insulator film 55 side and an iridium oxide layer 62 made of iridium oxide provided on the piezoelectric element 300 side. The first region 65 is a region facing the active part 320 of the first electrode 60. That is, the first region 65 is a region that defines the active part 320 of the first electrode 60. The second region 67 is a region of the first electrode 60 between the plurality of active units 320.

  Thick film portions 68 are respectively provided at both end portions 66 of the first region 65 of the first electrode 60 in the direction in which the pressure generating chambers 12 are juxtaposed. A thin film portion 69 thinner than the thick film portion 68 is provided between the two thick film portions 68 of the first electrode 60. That is, the first region 65 is composed of two thick film portions 68 and a thin film portion 69. Further, the thick film portion 68 is thicker than the thickness of the second region 67. Further, the thick film portion 68 is provided continuously with the iridium oxide layer 62 of the first electrode 60. Note that the length of the thick film portion 68 in the longitudinal direction of the piezoelectric element 300 is the same as the length of the first electrode 60 in the longitudinal direction of the first region 65.

  In this way, by providing the thick film portions 68 that are thicker than the thin film portions 69 and the second regions 67 at both ends 66 of the first regions 65 in the direction in which the pressure generating chambers 12 are arranged side by side, The rigidity of the 1st electrode 60 with respect to the stress concentration in the edge part 66 of the width direction of 65 piezoelectric elements 300 increases, and drive durability can be improved. In other words, there is no possibility that the diaphragm including the first electrode 60 is broken even if the driving of the piezoelectric element 300 is repeated. In particular, since the thick film portion 68 is provided continuously with the iridium oxide layer 62 which is stiffer than the platinum layer 61, the rigidity of the thick film portion 68 is further increased, and the driving durability of the piezoelectric element 300 is further improved. Can be made.

  Further, since the thick film portion 68 is formed at the end portion 66 of the first region 65, the thickness of the thin film portion 69 of the first region 65 is the same as that of the first region 65 of the first electrode 60, the elastic film 50, and the insulator film. The thickness can be suppressed to such an extent that the displacement of 55 is not hindered. Accordingly, the displacement of the first electrode 60, the elastic film 50, and the insulator film 55 (vibrating plate) due to the piezoelectric distortion of the piezoelectric element 300 is applied to the end portion 66 of the first region 65 of the first electrode. The destruction of the diaphragm due to stress concentration can be prevented.

  The first electrode 60 is continuously provided between the active units 320. That is, the first electrode 60 is provided continuously from the first region 65 to the second region 67. Thereby, the rigidity of the first electrode 60 with respect to an external force that causes the piezoelectric element 300 to deform the first region 65, the elastic film 50, and the insulator film 55 is improved, and the first region 60 of the first electrode 60 is changed from the first region 65 to the second region 67. Cracks are prevented from occurring. In the present embodiment, since the first electrode 60 includes the iridium oxide layer 62 that is stiffer than the platinum layer 61, the rigidity of the first electrode against the external force can be further increased.

  On the flow path forming substrate 10 on which such a piezoelectric element 300 is formed, a protective substrate 30 having a reservoir portion 32 constituting at least a part of the reservoir 100 is bonded via an adhesive 35. In this embodiment, the reservoir portion 32 is formed across the protective substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12. As described above, the communication portion 13 of the flow path forming substrate 10. The reservoir 100 is configured as a common ink chamber for the pressure generating chambers 12.

  A piezoelectric element holding portion 31 having 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 protective substrate 30. The piezoelectric element holding part 31 should just have the space of the grade which does not inhibit the motion of the piezoelectric element 300, and the said space may be sealed or may not be sealed.

  As such a protective substrate 30, it is preferable to use substantially the same material as the coefficient of thermal expansion of the flow path forming substrate 10, for example, glass, ceramic material, etc. In this embodiment, the same material as the flow path forming substrate 10 is used. The silicon single crystal substrate was used.

  The protective substrate 30 is provided with a through hole 33 that penetrates the protective substrate 30 in the thickness direction. The vicinity of the end portion of the lead electrode 90 drawn from each piezoelectric element 300 is provided so as to be exposed in the through hole 33.

  A drive circuit 120 for driving the piezoelectric elements 300 arranged in parallel is fixed on the protective substrate 30. For example, a circuit board or a semiconductor integrated circuit (IC) can be used as the drive circuit 120. The drive circuit 120 and the lead electrode 90 are electrically connected via a connection wiring 121 made of a conductive wire such as a bonding wire.

  In addition, a compliance substrate 40 including a sealing film 41 and a fixing plate 42 is bonded onto the protective substrate 30. Here, the sealing film 41 is made of a material having low rigidity and flexibility, and one surface of the reservoir portion 32 is sealed by the sealing film 41. The fixing plate 42 is formed of a relatively hard material. 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 the ink jet recording head 1 of this embodiment, after taking ink from an ink introduction port connected to an external ink supply means (not shown) and filling the interior from the reservoir 100 to the nozzle opening 21, the drive circuit In accordance with a recording signal from 120, a voltage is applied between each of the first electrode 60 and the second electrode 80 corresponding to the pressure generating chamber 12, and the elastic film 50, the insulator film 55, the first electrode 60, and the piezoelectric body. By bending and deforming the layer 70, the pressure in each pressure generation chamber 12 is increased, and ink droplets are ejected from the nozzle openings 21.

  Here, a method of manufacturing the ink jet recording head will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a method for manufacturing an ink jet recording head in the direction in which the pressure generating chambers are arranged.

First, as shown in FIG. 4A, silicon dioxide (SiO ₂₎ constituting an elastic film 50 on the surface of a flow path forming substrate wafer 110, which is a silicon wafer in which a plurality of flow path forming substrates 10 are integrally formed. ), An insulator film 55 made of, for example, zirconium oxide is formed on the elastic film 50 (silicon dioxide film 51), and a first electrode 60 is formed on the insulator film 55. .

  Specifically, the first electrode 60 is formed by forming a platinum layer 61 made of platinum on the insulator film 55 and forming an iridium oxide layer 62 made of iridium oxide on the platinum layer 61. Although the formation method of the platinum layer 61 and the iridium oxide layer 62 is not specifically limited, For example, sputtering method, chemical vapor deposition method (CVD method), physical vapor deposition method (PVD method) etc. are mentioned. By configuring the first electrode 60 from the platinum layer 61 and the iridium oxide layer 62 (metal oxide layer) that is more rigid than the platinum layer 61, the rigidity of the first electrode can be improved. In addition, the 1st electrode 60 is not limited to the structure mentioned above, Platinum, iridium, metals or metal oxides other than these materials can be used. When lead zirconate titanate (PZT) is used as the piezoelectric layer 70 as in the present embodiment, it is desirable that the material has little change in conductivity due to diffusion of lead oxide. As platinum, platinum and iridium are preferably used. In the present embodiment, the thickness of the first electrode 60 is about 20 nm.

  Next, as shown in FIG. 4B, the first electrode 60 is etched to form a thin film portion 69. Specifically, the first electrode 60 is patterned to partially remove a region that becomes the thin film portion 69 of the first electrode 60 in the thickness direction. The patterning of the first electrode 60 is performed by dry etching through a resist formed in a predetermined shape on the first electrode 60 by photolithography. In the present embodiment, the thin film portion 69 has a thickness of about 10 nm.

  Next, as shown in FIG. 4C, a piezoelectric layer 70 made of, for example, lead zirconate titanate (PZT) or the like, and a second electrode 80 made of, for example, iridium, are connected to the wafer 110 for flow path forming substrate. On the entire surface. The method for forming the piezoelectric layer 70 is not particularly limited. For example, in this embodiment, a so-called sol in which a metal organic substance is dissolved and dispersed in a solvent is applied, dried, gelled, and further fired at a high temperature. The piezoelectric layer 70 was formed by using a so-called sol-gel method for obtaining the piezoelectric layer 70 made of the following. The method for forming the piezoelectric layer 70 is not limited to the sol-gel method. For example, the piezoelectric layer 70 may be formed using a thin film forming method such as a MOD method or a sputtering method.

  Next, as shown in FIG. 5 (d), the piezoelectric layer 300 and the second electrode 80 are patterned in a region facing each pressure generating chamber 12 to form the piezoelectric element 300. Patterning of the piezoelectric layer 70 and the second electrode 80 can be performed collectively by dry etching through a resist formed in a predetermined shape on the second electrode 80 by photolithography. At this time, the second region 67 and the thick film portion 68 are formed by dry etching until the thickness of the region other than the region facing the piezoelectric element 300 of the first electrode 60 becomes thinner than the thick film portion 68. In dry etching, the iridium oxide layer 62 is left in the second region 67. In the present embodiment, the thickness of the second region 67 is about 10 nm. Further, by such dry etching, a thick film portion 68 having a height from the surface of the thin film portion 69 of about 10 nm is formed. The width of the thick film portion 68 is, for example, 0.5-2 μm, and is about 5-10% of the width of the piezoelectric element 300.

  Thereafter, although not particularly illustrated, a lead electrode 90 is formed for each piezoelectric element 300, and a protective substrate wafer which is a silicon wafer and serves as a plurality of protective substrates 30 is bonded to the piezoelectric element 300 side of the flow path forming substrate wafer 110. It joins with the agent 35. The protective substrate 30 is formed with a reservoir portion 32, a piezoelectric element holding portion 31 and the like in advance. Then, the flow path forming substrate wafer 110 is set to a predetermined thickness. Next, a mask film is newly formed on the channel forming substrate wafer 110, patterned into a predetermined shape, and the channel forming substrate wafer 110 is anisotropically etched using an alkaline solution such as KOH through the mask film. By performing (wet etching), the pressure generation chamber 12, the communication portion 13, the ink supply path 14, the communication path 15 and the like corresponding to the piezoelectric element 300 are formed.

  Thereafter, the mask film on the surface side where the pressure generation chamber 12 of the flow path forming substrate wafer 110 is opened is removed, and unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the protective substrate wafer are, for example, It is removed by cutting by dicing or the like. Then, the nozzle plate 20 having the nozzle openings 21 formed on the surface of the flow path forming substrate wafer 110 opposite to the protective substrate wafer is bonded, and the compliance substrate 40 is bonded to the protective substrate wafer. The ink jet recording head having the above-described structure is manufactured by dividing the flow path forming substrate wafer 110 and the like into a single chip size flow path forming substrate 10 as shown in FIG.

  These ink jet recording heads 1 are mounted on an ink jet recording apparatus. FIG. 5 is a perspective view illustrating a schematic configuration of an example of the ink jet recording apparatus.

  As shown in FIG. 5, the ink jet recording apparatus which is the liquid ejecting apparatus of the present embodiment has a plurality of different colors such as black (B), cyan (C), magenta (M), and yellow (Y). An ink jet recording head 1 (hereinafter referred to as a recording head) equipped with an ink cartridge (liquid storing means) 2 having a storage chamber for storing ink is provided. The recording head 1 is mounted on a carriage 3, and the carriage 3 on which the recording head 1 is mounted is provided on a carriage shaft 5 attached to the apparatus body 4 so as to be movable in the axial direction. Then, the driving force of the driving motor 6 is transmitted to the carriage 3 through a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 is moved along the carriage shaft 5. On the other hand, the apparatus main body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet (jetting medium) S such as paper fed by a paper feeding device (not shown) is conveyed on the platen 8. It has become so.

<Embodiment 2>
In the first embodiment, the thick film portion 68 is formed at the end portion 66 in the juxtaposed direction of the pressure generating chambers 12 in the first region 65 corresponding to the active portion 320 of the piezoelectric layer 70. It is not limited to an aspect. FIG. 6 is a cross-sectional view of the ink jet recording head according to the present embodiment. In addition, the same code | symbol is attached | subjected to the same thing as Embodiment 1, and the overlapping description is abbreviate | omitted.

  As shown in the figure, the piezoelectric element 300 has a shape in which the width in the direction in which the pressure generating chambers 12 are arranged gradually decreases from the first electrode 60 toward the second electrode 80. On the other hand, the piezoelectric layer 70 has an active part 320 sandwiched between the first electrode 60 and the second electrode 80, and the width in the juxtaposed direction is active on the first electrode 60 side of the piezoelectric layer 70. The width of the portion 320 is wider.

  The thick film portion 68 </ b> A extends from the end portion 66 in the juxtaposed direction of the first region 65 corresponding to the active portion 320 of the first electrode 60 to the end portion 71 in the juxtaposed direction of the piezoelectric layer 70. Further, the film thickness of the thick film portion 68 </ b> A is thicker than the thickness of the thin film portion 69 and the second region 67 of the first electrode 60. As described above, since the thick film portion 68A extends to the end portion 71 of the piezoelectric layer 70, the region facing the end portion 71 of the piezoelectric layer 70 of the first electrode 60 is against the stress applied to the region. The rigidity is increased, and the driving durability can be further improved.

<Other embodiments>
As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment. For example, in the first embodiment and the second embodiment described above, the thick film portion 68 is formed at the end portion in the width direction of the first region 65 of the first electrode 60. It may be formed at the end portion. In the first embodiment and the second embodiment described above, in the first electrode 60, the second region 67 and the thin film portion 69 have the same thickness, but may be different. Furthermore, in Embodiment 1 and Embodiment 2 described above, the thick film portion 68 is formed in accordance with the length of the lower electrode of the first region 65. However, the present invention is not particularly limited thereto. The length 68 may be formed in accordance with the length of the pressure generation chamber 12 in the longitudinal direction.

  Furthermore, in Embodiment 1 and Embodiment 2 described above, the piezoelectric layer 70 is formed by being individually patterned for each pressure generation chamber 12. However, the present invention is not limited to this, and the piezoelectric body common to each pressure generation chamber 12 is used. It may be a layer. That is, each piezoelectric element is formed of a common first electrode, a common piezoelectric layer, and an individual second electrode, and the common piezoelectric layer is connected to the common first electrode and each second electrode. It has a plurality of active parts sandwiched. Even in this case, by providing a thick film portion at the end of the first region corresponding to each active portion of the first electrode, rigidity against stress applied to the end of the first region is increased and driving durability is improved. can do.

  In the above-described ink jet recording apparatus, the ink jet recording head 1 is mounted on the carriage 3 and moves in the main scanning direction. However, the present invention is not particularly limited thereto. For example, the ink jet recording head 1 is fixed. Thus, the present invention can also be applied to a so-called line type recording apparatus that performs printing only by moving the recording sheet S such as paper in the sub-scanning direction.

  In the above-described embodiment, the ink jet recording head has been described as an example of the liquid ejecting head. However, the present invention is widely applied to all liquid ejecting heads, and the liquid ejecting ejects liquids other than ink. Of course, it can also be applied to the head. 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 (field emission 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.

  The present invention is not limited to a piezoelectric element mounted on a liquid jet head typified by an ink jet recording head, and can also be applied to a piezoelectric element mounted on another apparatus.

  DESCRIPTION OF SYMBOLS 1 Inkjet recording head (liquid jet head), 10 Flow path formation board | substrate (board | substrate), 12 Pressure generation chamber, 13 Communication part, 14 Ink supply path, 15 Communication path, 20 Nozzle plate, 21 Nozzle opening, 30 Protection board, 32 reservoir portion, 40 compliance substrate, 50 elastic film (silicon oxide film), 55 insulator film, 60 first electrode, 61 platinum layer, 62 zirconium oxide layer, 65 first region, 66, 71 end, 67 second Area, 68, 68A thick film part, 69 thin film part, 70 piezoelectric layer, 80 second electrode, 90 lead electrode, 100 reservoir, 300 piezoelectric element

Claims (6)

A flow path forming substrate in which a plurality of pressure generating chambers communicating with nozzle openings for injecting liquid are arranged in parallel;
A piezoelectric element comprising a first electrode, a piezoelectric layer, and a second electrode above the flow path forming substrate;
The piezoelectric layer has a plurality of active portions sandwiched between the first electrode and the second electrode,
The first electrode is formed over a plurality of the active portions, and at an end portion of the first region facing the active portion of the first electrode, a region other than the end portion of the first region. A thick film portion thicker than the thickness and the thickness of the second region between the active portions of the first electrode is provided ;
The liquid ejecting head according to claim 1, wherein the thick film portion is provided on the piezoelectric layer side of the first electrode and protrudes toward the piezoelectric layer side . The liquid ejecting head according to claim 1,
The piezoelectric layer is individually formed for each pressure generation chamber,
The width of the active portion in the juxtaposed direction of the pressure generating chambers is substantially the same as the width of the piezoelectric layer in the juxtaposed direction,
The liquid jet head, wherein the thick film portion is formed at an end portion of the first region in the juxtaposed direction. The liquid ejecting head according to claim 1,
The piezoelectric layer is individually formed for each of the pressure generating chambers having a width wider than the width of the active portion in the juxtaposed direction,
The liquid jet head, wherein the thick film portion extends from an end portion of the first region to an end portion of the piezoelectric layer in the juxtaposed direction. In the liquid jet head according to any one of claims 1 to 3,
The liquid ejecting head according to claim 1, wherein the first electrode has an iridium oxide layer formed continuously from the iridium oxide on the entire surface on the piezoelectric layer side.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1. Comprising a piezoelectric element comprising a first electrode, a piezoelectric layer and a second electrode;
The piezoelectric layer has a plurality of active portions sandwiched between the first electrode and the second electrode,
The first electrode is formed over a plurality of the active portions, and a thickness of a region other than the end portion of the first region is formed at an end portion of the first region corresponding to the active portion of the first electrode. And a thicker film portion thicker than the thickness of the second region between the active portions of the first electrode ,
The actuator device according to claim 1, wherein the thick film portion is provided on the piezoelectric layer side of the first electrode and protrudes to the piezoelectric layer side .

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