JP2010228274A - Liquid jetting head and liquid jetting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid jetting head having highly-densified nozzle openings and a liquid delivering characteristics of which the variation and degradation is suppressed, and to provide a liquid jetting device. <P>SOLUTION: A partition wall 11 of a pressure generating chamber 12 on a flow channel forming substrate 10 in a width direction includes a narrow width part 18 provided at a pressure generating means 300 side and a wide width part 19 that is provided at an opposite side of the pressure generating means 300 and has a width larger than that of the narrow width part 18. The width of the narrow width part 18 is not less than one-tenth of the width of the wide width part 19 and is in a range from 5 to 15 μm. A length of the narrow width part 18 in a depth direction of the pressure generating chamber 12 is shorter than a depth of the pressure generating chamber 12 and is not less than one-tenth of the depth of the pressure generating chamber 12. The length of the narrow width part 18 is in a range from 2 to 20 μm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus that eject liquid, and more particularly, to an ink jet recording head and an ink jet recording apparatus that eject ink.

  A typical example of the liquid ejecting head is an ink jet recording head that ejects ink droplets from nozzles. As an ink jet recording head, for example, a part of a pressure generation chamber communicating with a nozzle for ejecting ink droplets is configured by a vibration plate, and the vibration plate is deformed by a piezoelectric element to pressurize ink in the pressure generation chamber. Some eject ink droplets from nozzles. In addition, as a piezoelectric element employed in an ink jet recording head, for example, an element composed of a pair of electrodes and a piezoelectric layer sandwiched between these electrodes is known.

  In addition, an ink jet recording head has been proposed in which the diaphragm side of the pressure generating chamber is wide (see, for example, Patent Documents 1 to 4).

Japanese Patent No. 3882936 JP-A-11-227190 JP 2004-209874 A Japanese Patent No. 3713921

  However, as the density of nozzle openings is increased, there is a problem that the partition wall defining the pressure generating chamber becomes thinner and the rigidity is lowered. Then, when the rigidity of the partition wall is lowered, the partition wall is bent and deformed to the adjacent pressure generation chamber side in accordance with the pressure fluctuation of the ink in the pressure generation chamber due to the operation of the pressure generation unit when ink is ejected from a certain nozzle opening. There is a possibility that pressure loss (crosstalk) occurs, and ejection characteristics such as a decrease in the flying speed of the ink and a decrease in the ink ejection amount change. In addition, in order to improve the rigidity of the partition wall, increasing the thickness of the partition wall (width in the direction in which the pressure generating chambers are arranged in parallel) reduces the volume of the pressure generating chamber and the area in which the pressure generating means is displaced. Therefore, desired ink ejection characteristics cannot be obtained.

  Incidentally, in the configurations of Patent Documents 1 to 4, although a wide portion is disclosed, the thickness of the partition wall for suppressing crosstalk is not defined.

  Such a problem is not limited to the ink jet recording head, and similarly exists in a liquid ejecting head that ejects another liquid.

  In view of such circumstances, an object of the present invention is to provide a liquid ejecting head and a liquid ejecting apparatus that increase the density of nozzle openings and suppress variation and decrease in liquid ejection characteristics.

  An aspect of the present invention that solves the above problems includes a flow path forming substrate in which a pressure generation chamber communicating with a nozzle opening is partitioned by a partition wall in the width direction and provided on one surface side of the flow path forming substrate. Pressure generating means for causing a pressure change in the pressure generating chamber, and the partition in the width direction of the pressure generating chamber of the flow path forming substrate is a narrow width provided on the pressure generating means side. And a wide portion provided on the opposite side of the pressure generating means and having a width larger than the narrow portion, and the width of the narrow portion is 1/10 or more of the width of the wide portion. The narrow portion has a width of 5 μm to 15 μm, and the length of the narrow portion in the direction from the one surface where the pressure generating means of the pressure generating chamber is provided to the other surface. Is shorter than the depth of the pressure generating chamber, and The liquid ejecting head has a length of 1/10 or more of the depth of the pressure generating chamber, and the length of the narrow portion is 2 μm to 20 μm.

  In this aspect, since the partition wall is configured by the narrow part provided on the pressure generating means side and the wide part, the wide part can increase the rigidity of the partition compared to the partition configured by only the narrow part. it can. Thereby, even if the pressure generating chambers are arranged at a high density as in the prior art, the generation of pressure loss (crosstalk) between the pressure generating chambers due to the partition walls can be reduced, and the liquid ejection characteristics can be improved. In addition, by increasing the rigidity of the partition wall and making it difficult for the partition wall to deform, liquid can be discharged from only one of the adjacent nozzle openings with the partition wall sandwiched between when the liquid is discharged simultaneously from the adjacent nozzle openings. The liquid ejection characteristics can be made uniform in the case of ejection. Further, by forming the narrow portion on the pressure generating means side of the partition wall, it is possible to provide a widened portion that widens the width of the pressure generating chamber. By this widened portion, it is possible to widen a vibrable region that can be used for the displacement of the pressure generating means, improve the displacement characteristics of the pressure generating means, and improve the liquid ejection characteristics.

  Moreover, it is preferable that the inner surface of the recessed part defined by the said wide part of the said partition is formed in the curved surface shape. According to this, generation | occurrence | production of malfunctions, such as a bubble staying in the corner | angular part in a recessed part, can be suppressed.

  Moreover, it is preferable that a diaphragm is formed on the pressure generating means side of the flow path forming substrate, and at least a part of the narrow portion may be formed on the diaphragm. According to this, it is possible to widen the vibration region of the diaphragm and improve the liquid ejection characteristics.

  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 that can improve high-density printing and print quality can be realized.

FIG. 2 is an exploded perspective view of a recording head according to Embodiment 1 of the invention. 2A and 2B are a plan view and a cross-sectional view of the recording head according to Embodiment 1 of the invention. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment of the invention. FIG. 5 is a cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. FIG. 5 is a cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. FIG. 5 is a cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. FIG. 5 is a cross-sectional view illustrating the method for manufacturing the recording head according to the first embodiment of the invention. FIG. 6 is a cross-sectional view of a recording head according to Embodiment 2 of the invention. FIG. 6 is a cross-sectional view of a recording head according to Embodiment 3 of the invention. 1 is a schematic diagram of a recording apparatus according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is an exploded perspective view illustrating an ink jet recording head that is an example of a liquid ejecting head according to Embodiment 1 of the present invention, and FIG. 2 is a plan view and a cross-sectional view taken along line AA ′ of the ink jet recording head. FIG. 3 is a cross-sectional view taken along line BB ′ of FIG.

  The flow path forming substrate 10 constituting the ink jet recording head I of the present embodiment is made of a silicon single crystal substrate, and an elastic film 50 mainly composed of silicon oxide is formed on one surface thereof.

  In the flow path forming substrate 10, a plurality of pressure generating chambers 12 partitioned by a partition wall 11 are arranged in parallel in the width 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 31 of a protective substrate, which will be described later, and constitutes a part of a reservoir that becomes a common ink chamber of each pressure generating chamber 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 the present embodiment, the flow path forming substrate 10 is provided with a liquid flow path including a pressure generation chamber 12, a communication portion 13, an ink supply path 14, and a communication path 15. The ink supply path 14 and the communication path 15 are defined.

  Further, the width of the pressure generation chamber 12 (the width in the short direction, which is the direction in which the pressure generation chambers 12 are juxtaposed), is disposed on the elastic film 50 side of each pressure generation chamber 12 (on the piezoelectric element 300 side, which will be described later). The widened portion 16 extending in the direction is provided along the longitudinal direction. The widened portion 16 is defined by a concave portion 17 provided in the longitudinal direction of the pressure generating chamber 12 on the elastic membrane 50 side of the partition wall 11 defining the pressure generating chamber 12.

  By forming the recess 17 in the partition 11 in this way, the partition 11 between the adjacent pressure generating chambers 12 has a narrow width (thickness) in the region where the recess 17 on the elastic film 50 side is formed. The part 18 and the recessed part 17 are not formed, and a wide part 19 having a larger width (thickness) than the narrow part 18 is provided.

Here, the width W ₂ of the narrow portion 18 is formed under a condition that satisfies 1.0 <(W ₁ / W ₂ ) ≦ 10 with respect to the width W ₁ of the wide portion 19 of the partition wall 11. In other words, the width W ₂ of the narrow portion 18 is narrower than the width W ₁ of the wide portion 19 and has a size of 1/10 or more. The width _{W 2} of the narrow portion 18 is formed in 5Myuemu～15myuemu.

Further, the thickness direction of the flow path forming substrate 10, that is, from one surface on which the elastic film 50 (a piezoelectric element 300 which is a pressure generating means to be described later in detail) is provided to the other surface (the surface on which the pressure generating chamber 12 opens). The length D ₂ of the narrow portion 18 toward the surface is formed on the condition that satisfies 1.0 <(D ₁ / D ₂ ) ≦ 10 with respect to the depth D ₁ of the pressure generation chamber 12. Incidentally, the length D < _b > ₂ of the narrow portion 18 is the depth of the concave portion 17. The length D2 of the narrow portion 18 is ₂ μm to 20 μm.

  Moreover, the inner surface of the recessed part 17 is formed in the curved surface shape. The inner surface of the recess 17 having a curved surface means that the recess 17 has no corners on the inner surface. Thus, by making the inner surface of the recessed part 17 into a curved surface shape, it is possible to suppress problems such as bubbles adhering to the corners of the inner surface of the recessed part 17.

  In this embodiment, the concave portion 17 is formed only in the region that defines the pressure generation chamber 12 of the partition wall 11. However, the concave portion 17 is formed in the region that defines the pressure generation chamber 12, the ink supply path 14, and the communication path 15. You may make it provide continuously over. Of course, the present invention is not limited to the partition wall 11 that defines the width direction of the pressure generation chamber 12, and the recess portion 17 may be formed in the wall portion that defines the end of the pressure generation chamber 12 in the short direction. Good.

  Such a pressure generation chamber 12, the communication portion 13, the ink supply path 14, the communication path 15, and the recess 17 can be formed by etching the flow path forming substrate 10. These manufacturing methods will be described later in detail.

  Further, on the opening surface side, which is the other surface opposite to the one surface on which the elastic film 50 of the flow path forming substrate 10 is formed, in the vicinity of the end portion of each pressure generating chamber 12 on the opposite side to the ink supply path 14. A nozzle plate 20 having a nozzle opening 21 communicating therewith is fixed by an adhesive, a heat welding film, or the like. The nozzle plate 20 is made of, for example, glass ceramics, a silicon single crystal substrate, stainless steel, or the like.

  On the other hand, an elastic film 50 is formed on the side opposite to the opening surface of the flow path forming substrate 10, and an insulating film 55 mainly composed of zirconium oxide is formed on the elastic film 50. Yes. Further, the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are laminated on the insulator film 55 to form the piezoelectric element 300 (the pressure generating means of the present embodiment). Yes. Here, the piezoelectric element 300 refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 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 this case, 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 320. In the present embodiment, the first electrode 60 is a common electrode of the piezoelectric element 300, and the second electrode 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 addition, the piezoelectric element 300 that is displaced by driving is referred to as an actuator device. In the above-described example, the elastic film 50, the insulator film 55, and the first electrode 60 function as a diaphragm. However, the present invention is not limited to this. For example, the elastic film 50 and the insulator film 55 are provided. Instead, only the first electrode 60 may act as a diaphragm. Further, the piezoelectric element 300 itself may substantially serve as a diaphragm.

The piezoelectric layer 70 is made of a piezoelectric material that is formed on the first electrode 60 and has an electromechanical conversion action, and in particular, a metal oxide having a perovskite structure represented by the general formula ABO ₃ among the piezoelectric materials. As the piezoelectric layer 70, for example, a ferroelectric material such as lead zirconate titanate (PZT) or a material obtained by adding a metal oxide such as niobium oxide, nickel oxide, or magnesium oxide to the ferroelectric material is suitable. Specifically, lead titanate (PbTiO ₃ ), lead zirconate titanate (Pb (Zr, Ti) O ₃ ), lead zirconate (PbZrO ₃ ), lead lanthanum titanate ((Pb, La), TiO ₃ ) ), Lead lanthanum zirconate titanate ((Pb, La) (Zr, Ti) O ₃ ), lead magnesium titanate zirconate titanate (Pb (Zr, Ti) (Mg, Nb) O ₃ ), etc. Can do.

  The piezoelectric layer 70 is formed thick enough to suppress the thickness so as not to generate cracks in the manufacturing process and to exhibit sufficient displacement characteristics. For example, in this embodiment, the piezoelectric layer 70 is formed with a thickness of about 0.5 to 5 μm.

  Each second electrode 80 which is an individual electrode of the piezoelectric element 300 is made of, for example, gold (Au) or the like which is drawn from the vicinity of the end on the ink supply path 14 side and extends to the insulator film 55. A lead electrode 90 is connected.

  On the flow path forming substrate 10 on which such a piezoelectric element 300 is formed, that is, on the first electrode 60, the insulator film 55, and the lead electrode 90, there is a reservoir portion 31 that constitutes at least a part of the reservoir 100. The protective substrate 30 is bonded via an adhesive 35. In the present embodiment, the reservoir portion 31 is formed across the protective substrate 30 in the thickness direction and across the width direction of the pressure generating chamber 12, and as described above, the communication portion 13 of the flow path forming substrate 10 is formed. The reservoir 100 is configured as a common ink chamber for the pressure generating chambers 12. Alternatively, the communication portion 13 of the flow path forming substrate 10 may be divided into a plurality of pressure generation chambers 12 and only the reservoir portion 31 may be used as the reservoir. Further, for example, only the pressure generating chamber 12 is provided in the flow path forming substrate 10, and a reservoir is provided on a member (for example, the elastic film 50, the insulator film 55, etc.) interposed between the flow path forming substrate 10 and the protective substrate 30. An ink supply path 14 that communicates with each pressure generating chamber 12 may be provided.

  A piezoelectric element holding portion 32 having a space that does not hinder the movement of the piezoelectric element 300 is provided in a region of the protective substrate 30 that faces the piezoelectric element 300. The piezoelectric element holding part 32 only needs to have a space that does not hinder the movement of the piezoelectric element 300, and the space may be sealed or unsealed.

  As such a protective substrate 30, it is preferable to use a material substantially the same as the coefficient of thermal expansion of the flow path forming substrate 10, for example, a glass, a ceramic material or the like. 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 31 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 I of this embodiment, ink is taken in from an ink introduction port connected to an ink storage means such as an ink cartridge or an ink tank, and the interior is filled with ink from the reservoir 100 to the nozzle opening 21. Thereafter, a voltage is applied between each of the first electrode 60 and the second electrode 80 corresponding to the pressure generation chamber 12 in accordance with a recording signal from the drive circuit 120, and the elastic film 50, the insulator film 55, and the first electrode. By bending and deforming 60 and the piezoelectric layer 70, the pressure in each pressure generating chamber 12 is increased and ink droplets are ejected from the nozzle openings 21.

  In the ink jet recording head I of the present embodiment, the partition wall 11 that defines the pressure generating chamber 12 is provided on the side opposite to the piezoelectric element 300 and the narrow portion 18 provided on the piezoelectric element 300 side that is the pressure generating means. The wide part 19 is used. For this reason, the rigidity of the partition 11 can be increased by the wide portion 19 as compared with the partition configured only by the narrow portion 18. As a result, even if the pressure generating chambers 12 are arranged at a high density as in the prior art, the generation of pressure loss (crosstalk) between the pressure generating chambers 12 due to the partition walls 11 is reduced, and ink ejection characteristics are improved. Can do.

  Further, by increasing the rigidity of the partition wall 11 to make it difficult to deform the partition wall 11, when ink is ejected from the adjacent nozzle openings 21 across the partition wall 11, and from one of the adjacent nozzle openings 21 across the partition wall 11. Ink ejection characteristics can be made uniform when ink is ejected and ink is not ejected from the other. By the way, if the amount of deformation of the partition wall 11 changes when the discharge conditions (such as the number of nozzle openings 21 for discharging ink) are different, pressure loss (crosstalk between the pressure generation chambers 12) occurs and ink discharge characteristics. Cannot be aligned.

  Further, by forming the narrow portion 18 on the piezoelectric element 300 side of the partition wall 11, it is possible to provide the widened portion 16 that widens the width of the pressure generating chamber 12 on the piezoelectric element 300 side of the pressure generating chamber 12. The widened portion 16 can widen a vibrable region that can be used for the displacement of the piezoelectric element 300, and can improve the displacement characteristics of the piezoelectric element 300. Incidentally, if the partition wall is formed only by the wide portion 19, the opening area of the pressure generating chamber 12 on the piezoelectric element 300 side is narrowed, and the vibrable region is reduced, making it impossible to cause the piezoelectric element 300 to perform a desired displacement.

  Hereinafter, an example of a manufacturing method for manufacturing such an ink jet recording head I will be described with reference to FIGS. 4 to 7 are cross-sectional views in the juxtaposition direction of the pressure generating chambers showing the method of manufacturing the ink jet recording head according to the first embodiment of the present invention.

  First, as shown in FIG. 4A, impurities are doped on the surface side of the wafer 110 for flow path forming substrate 110, which is a silicon wafer and in which a plurality of flow path forming substrates 10 are integrally formed, on which the piezoelectric element 300 is formed. Thus, the doped layer 111 is formed.

Here, as an impurity doped in the doped layer 111, for example, boron is cited. In this way, the doped layer 111 doped with boron is formed in another region of the flow path forming substrate wafer 110, which is a silicon single crystal substrate, when anisotropic etching using an alkaline solution is performed in a later step. The etching rate is faster than that. Then, in a later step, the recesses 17 are formed in the doped layer 111 by utilizing the difference in etching rate between the doped layer 111 doped with impurities and other regions. Therefore, the thickness of the doped layer 111 doped with impurities may be defined based on the depth (D ₂ ) of the recess 17.

  Next, as shown in FIG. 4B, a silicon dioxide film 51 constituting the elastic film 50 is formed on one surface (on the dope layer 111 side) of the flow path forming substrate wafer 110. The silicon dioxide film 51 can be formed by, for example, a sputtering method or a chemical vapor deposition method (CVD method). Further, the silicon dioxide film 51 can also be formed by thermally oxidizing the flow path forming substrate wafer 110. When the silicon dioxide film 51 is formed by thermal oxidation, the doped layer 111 is formed on one surface of the flow path forming substrate wafer 110. Therefore, the silicon dioxide film 51 is mainly composed of silicon dioxide and has impurities. It will be doped. That is, the silicon dioxide film 51 is formed of silicon oxide doped with boron.

  Next, as shown in FIG. 4C, an insulator film 55 made of zirconium oxide is formed on the elastic film 50. In this embodiment, after forming a zirconium layer containing zirconium as a main component on the elastic film 50, the zirconium layer is thermally oxidized in a diffusion furnace at 500 to 1200 ° C., for example, to thereby mainly contain zirconium oxide. An insulator film 55 was formed.

  Next, as shown in FIG. 4D, the first electrode 60 is formed on the entire surface of the insulator film 55 and patterned into a predetermined shape. The material of the first electrode 60 is not particularly limited. However, when lead zirconate titanate (PZT) is used as the piezoelectric layer 70, it is desirable that the material has little change in conductivity due to diffusion of lead oxide. . For this reason, platinum, iridium, etc. are used suitably as a material of the 1st electrode 60. FIG. Moreover, the 1st electrode 60 can be formed by sputtering method, PVD method (physical vapor deposition method), etc., for example.

  Next, as shown in FIG. 5A, for example, a piezoelectric layer 70 made of lead zirconate titanate (PZT) or the like, and a second electrode 80 made of iridium, for example, are used. On the entire surface. In this embodiment, the piezoelectric layer 70 is formed by applying and drying a so-called sol obtained by dissolving and dispersing a metal organic substance in a solvent, gelling it, and baking it at a high temperature to form a piezoelectric layer made of a metal oxide. The piezoelectric layer 70 was formed using a so-called sol-gel method for obtaining 70. The method for forming the piezoelectric layer 70 is not particularly limited. For example, a PVD (Physical Vapor Deposition) method such as a MOD (Metal-Organic Decomposition) method, a sputtering method, or a laser ablation method may be used.

  Next, as shown in FIG. 5B, the second electrode 80 and the piezoelectric layer 70 are simultaneously etched to form the piezoelectric element 300 in a region corresponding to each pressure generating chamber 12. Here, examples of the etching of the second electrode 80 and the piezoelectric layer 70 include dry etching such as reactive ion etching and ion milling.

  Next, as shown in FIG. 5C, a lead electrode 90 made of gold (Au) is formed over the entire surface of the flow path forming substrate wafer 110 and then patterned for each piezoelectric element 300.

  Next, as shown in FIG. 6A, the protective substrate wafer 130 is bonded onto the flow path forming substrate wafer 110 via an adhesive 35. Here, the protective substrate wafer 130 is formed by integrally forming a plurality of protective substrates 30, and the reservoir portion 31 and the piezoelectric element holding portion 32 are formed in advance on the protective substrate wafer 130. By joining the protective substrate wafer 130, the rigidity of the flow path forming substrate wafer 110 is remarkably improved.

  Next, as shown in FIG. 6B, the flow path forming substrate wafer 110 is thinned to a predetermined thickness.

  Next, as shown in FIG. 7A, a mask film 52 is newly formed on the flow path forming substrate wafer 110 and patterned into a predetermined shape. 7B, the flow path forming substrate wafer 110 is anisotropically etched (wet etching) using an alkaline solution such as KOH through the mask film 52, whereby the piezoelectric element 300 is formed. Corresponding pressure generating chambers 12, communication portions 13, ink supply passages 14, communication passages 15 and the like are formed.

  At this time, the doped layer 111 doped with impurities is formed on the piezoelectric element 300 side of the flow path forming substrate wafer 110 as described above, and this doped layer 111 is formed in another region (impurities doped). Since the etching rate is higher than that of the non-silicon region, the widened portion 16 (recessed portion 17) in which the width of the pressure generating chamber 12 is widened is formed in the doped layer 111. Thus, the narrow portion 18 is formed on the partition wall 11 on the piezoelectric element 300 side, and the wide portion 19 having a larger width (thickness) than the narrow portion 18 is formed on the side opposite to the piezoelectric element 300. The

  Moreover, since the recessed part 17 which forms the narrow part 18 is formed by etching the dope layer 111, the inner surface is formed in a curved surface shape.

  Thereafter, the mask film 52 on the surface of the flow path forming substrate wafer 110 is removed, and unnecessary portions of the outer peripheral edge portions of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are cut by, for example, dicing. Remove. 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 130 is bonded, and the compliance substrate 40 is bonded to the protective substrate wafer 130. By dividing the flow path forming substrate wafer 110 and the like into a single chip size flow path forming substrate 10 and the like as shown in FIG. 1, the ink jet recording head of this embodiment is obtained.

(Embodiment 2)
FIG. 8 is a cross-sectional view of the main part in the direction in which the pressure generating chambers of the ink jet recording head which is an example of the liquid jet head according to the second embodiment of the present invention are arranged. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

As shown in FIG. 8, in the ink jet recording head I of the present embodiment, the pressure generation chamber 12 </ b> A extends to the middle of the elastic film 50 in the thickness direction. Specifically, a widened portion 16A is formed on the pressure generating chamber 12A on the piezoelectric element 300 side, and the widened portion 16A is provided across the flow path forming substrate 10 and the elastic film 50. That is, the partition wall 11A that defines the juxtaposed direction (width direction) of the pressure generating chambers 12A includes the flow path forming substrate 10 and a part of the elastic film 50 in the thickness direction, and the recess 17A of the partition wall 11A. Is formed at the boundary portion between the flow path forming substrate 10 and the elastic film 50, so that the narrow portion 18A of the partition wall 11A is formed by a part of the flow path forming substrate 10 and the elastic film 50 in the thickness direction. . On the other hand, the wide part 19 of the partition wall 11 </ b> A is formed only by the flow path forming substrate 10.
Even with this configuration, the same effects as those of the first embodiment described above can be achieved.

(Embodiment 3)
FIG. 9 is a cross-sectional view of the main part in the direction in which the pressure generating chambers of the ink jet recording head which is an example of the liquid jet head according to the second embodiment of the present invention are arranged. In addition, the same code | symbol is attached | subjected to the member similar to embodiment mentioned above, and the overlapping description is abbreviate | omitted.

As shown in FIG. 9, in the ink jet recording head I of this embodiment, the pressure generating chamber 12B is provided so as to penetrate the elastic film 50 in the thickness direction. Specifically, a widened portion 16B is formed on the pressure generating chamber 12B on the piezoelectric element 300 side, and the widened portion 16B is provided so as to penetrate the elastic film 50 in the thickness direction. That is, the partition wall 11B is composed of the flow path forming substrate 10 and the elastic film 50, and the recess 17B of the partition wall 11B is formed in the elastic film 50, so that the narrow part 18B of the partition wall 11B is only the elastic film 50. It is formed with. On the other hand, the wide part 19 of the partition wall 11 </ b> B is formed only by the flow path forming substrate 10.
Even with this configuration, the same effects as those of the first embodiment described above can be achieved.

  Incidentally, the manufacturing method of the recesses 17A and 17B of the second and third embodiments described above is not particularly limited. For example, only a part of the pressure generating chambers 12A and 12B penetrating the flow path forming substrate 10 is anisotropically etched. After the formation, the widened portions 16A and 16B (recessed portions 17A and 17B) may be formed by further dry-etching or isotropically etching the pressure generating chambers 12A and 12B on the elastic film 50 side. Even in the case of anisotropic etching, the widened portions 16A and 16B (recessed portions 17A and 17B) can be formed because overetching is performed in the lateral direction (width direction).

  In addition, as another method, for example, partition walls 11A and 11B formed only by the flow path forming substrate 10 after part of the pressure generating chambers 12A and 12B penetrating the flow path forming substrate 10 is formed by anisotropic etching. The widened portions 16A and 16B (recessed portions 17A and 17B) may be formed by forming a protective film having etching resistance on the top and then further etching. Of course, these methods are not limited to the above-described second and third embodiments, and the widened portion 16 (recessed portion 17) of the above-described first embodiment can be formed by the same method.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above. For example, in the first embodiment described above, a silicon single crystal substrate is exemplified as the flow path forming substrate 10, but the present invention is not particularly limited thereto. For example, a material such as an SOI substrate or glass may be used.

  In the first embodiment described above, the actuator device having the thin film type piezoelectric element 300 is described as the pressure generating means for causing the pressure change in the pressure generating chamber 12, but the invention is not particularly limited thereto. It is possible to use a thick film type actuator device formed by a method such as attaching a green sheet or a longitudinal vibration type actuator device in which piezoelectric materials and electrode forming materials are alternately stacked to expand and contract in the axial direction. it can. In addition, a so-called electrostatic actuator that generates static electricity between the diaphragm and the electrode, deforms the diaphragm by electrostatic force, and ejects droplets from the nozzle openings can be used.

  The ink jet recording head I described above 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. 10 is a schematic view showing an example of the ink jet recording apparatus.

  In the ink jet recording apparatus II shown in FIG. 10, the recording head units 1A and 1B having the ink jet recording head I are detachably provided with cartridges 2A and 2B constituting ink supply means, and the recording head units 1A and 1B. Is mounted on a carriage shaft 5 attached to the apparatus main 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 that is a recording medium such as paper fed by a paper feed roller (not shown) is wound around the platen 8. It is designed to be transported.

  In the ink jet recording apparatus II described above, the ink jet recording head I (head units 1A, 1B) is mounted on the carriage 3 and moves in the main scanning direction. However, the present invention is not particularly limited thereto. The present invention can also be applied to a so-called line recording apparatus in which the ink jet recording head I is fixed and printing is performed simply by moving the recording sheet S such as paper in the sub-scanning direction.

  Furthermore, the present invention is intended for a wide range of liquid jet heads in general, for example, for manufacturing recording heads such as various ink jet recording heads used in image recording apparatuses such as printers, and color filters such as liquid crystal displays. The present invention can also be applied to a coloring material ejecting head, an organic EL display, an electrode material ejecting head used for forming an electrode such as an FED (field emission display), a bioorganic matter ejecting head used for biochip production, and the like.

  Further, although the ink jet recording apparatus II has been described as an example of the liquid ejecting apparatus, the liquid ejecting apparatus using the other liquid ejecting heads described above can also be used.

  I ink jet recording head (liquid ejecting head), II ink jet recording apparatus (liquid ejecting apparatus), 10 flow path forming substrate, 11, 11A, 11B partition, 12, 12A, 12B pressure generating chamber, 13 communicating portion, 14 ink Supply path, 15 communication path, 16, 16A, 16B widened portion, 17, 17A, 17B recessed portion, 18, 18A, 18B narrowed portion, 19 widened portion, 20 nozzle plate, 21 nozzle opening, 30 protective substrate, 31 reservoir portion 32 piezoelectric element holder, 40 compliance substrate, 50 elastic film, 55 insulator film, 60 first electrode, 70 piezoelectric layer, 80 second electrode, 90 lead electrode, 100 reservoir, 120 drive circuit, 121 connection wiring, 300 Piezoelectric element (pressure generating means)

Claims (5)

A flow path forming substrate provided with a plurality of pressure generating chambers communicating with the nozzle openings and partitioned by a partition wall in the width direction;
Pressure generating means provided on one side of the flow path forming substrate to cause a pressure change in the pressure generating chamber,
The partition wall in the width direction of the pressure generating chamber of the flow path forming substrate is provided with a narrow portion provided on the pressure generating means side, and on a side opposite to the pressure generating means, and more than the narrow portion. A wide portion having a large width,
The width of the narrow portion has a size of 1/10 or more of the width of the wide portion, and the narrow portion has a width of 5 μm to 15 μm,
The length of the narrow portion is shorter than the depth of the pressure generating chamber and the depth of the pressure generating chamber in a direction from one surface of the pressure generating chamber where the pressure generating means is provided to the other surface. The liquid ejecting head is characterized in that the length of the narrow portion is 2 μm to 20 μm.   The liquid ejecting head according to claim 1, wherein an inner surface of the concave portion defined by the wide portion of the partition wall is formed in a curved surface shape.   The liquid jet head according to claim 1, wherein a vibration plate is formed on the pressure generating unit side of the flow path forming substrate.   The liquid ejecting head according to claim 3, wherein at least a part of the narrow portion is formed on the vibration plate.   A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.

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