JP3682567B2 - Thin film device manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thin film device and a manufacturing method thereof, and in particular, a part of a pressure generation chamber communicating with a nozzle opening for ejecting ink droplets is configured by a diaphragm, and a piezoelectric layer on the surface of the diaphragm is formed. The present invention is suitable for application to an ink jet recording head that ejects ink droplets by displacement of a piezoelectric layer.
[0002]
[Prior art]
The ink jet recording head has a piezoelectric vibration type that pressurizes ink by mechanically deforming a pressure generation chamber, and a heating element provided in the pressure generation chamber, and ink is applied by pressure of bubbles generated by heat of the heating element. There are two types, a bubble jet type that pressurizes. Piezoelectric vibration type recording heads are further classified into two types: a first recording head using a piezoelectric vibrator that is displaced in the axial direction and a second recording head using a piezoelectric vibrator that is flexibly displaced. . The first recording head can be driven at a high speed and can be recorded at a high density. On the other hand, the processing of the piezoelectric vibrator is accompanied by a cutting operation, or is fixed when the piezoelectric vibrator is fixed to the pressure generating chamber. There is a problem that the number of manufacturing steps increases because of the need for a dimensional assembly work.
[0003]
On the other hand, the second recording head uses a silicon single crystal substrate as a base material, and forms flow paths such as a pressure generation chamber and a reservoir by anisotropic etching, and a piezoelectric vibrator is made of a piezoelectric material. By using a film formation technique such as sputtering, the elastic film can be made extremely thin, and the pressure generation chamber and piezoelectric vibrator can be formed with high accuracy. Can be improved.
[0004]
On the other hand, in order to eliminate the inconvenience of the latter recording head, a uniform piezoelectric material layer is formed by thin film technology over the entire surface of the diaphragm as seen in Japanese Patent Laid-Open No. 5-286131. It has been proposed to divide the layer into shapes corresponding to the pressure generation chambers by lithography and form piezoelectric vibrators so that each pressure generation chamber is independent.
[0005]
This eliminates the need to affix the piezoelectric vibrator to the diaphragm, so that not only can the piezoelectric vibrator be created by a precise and simple technique called lithography, but also the thickness of the piezoelectric vibrator can be reduced. There is an advantage that it can be made thin and can be driven at high speed.
[0006]
[Problems to be solved by the invention]
However, in the above-described lithography method, the piezoelectric layer and the upper electrode layer are usually patterned by dry etching such as ion milling, but at this time, there is a problem that the piezoelectric layer is damaged and the piezoelectric characteristics are deteriorated. This is presumably because electric charges are accumulated in the upper electrode layer during etching and a potential difference is generated between the upper and lower electrodes. In order to prevent this, there is a method of etching while neutralizing the ions from the ion gun with electrons by installing a neutralizer between the ion gun and the substrate to be etched during etching. A voltage difference is generated between the upper and lower electrodes, and the deterioration of the piezoelectric characteristics of the piezoelectric layer cannot be completely prevented.
[0007]
Such a problem occurs not only in an ink jet recording head but also in a thin film device using a piezoelectric layer.
[0008]
In view of such circumstances, it is an object of the present invention to provide a thin film device and a method for manufacturing the same, in which deterioration of piezoelectric characteristics of the piezoelectric layer is prevented.
[0009]
[Means for Solving the Problems]
According to an aspect of the present invention for solving the above-described problem, in the method of manufacturing a thin film device having a multilayer structure in which a lower electrode layer, a piezoelectric layer, and an upper electrode layer are sequentially laminated on one surface of a substrate, the lower electrode layer is Forming the piezoelectric layer so that at least a part of the lower electrode layer is exposed on the lower electrode layer, and at least the exposed portion on the piezoelectric layer. Forming the upper electrode layer connected to the lower electrode layer, and grounding at least the upper electrode layer when patterning the piezoelectric layer and the upper electrode layer by dry etching And a method for manufacturing a thin film device.
[0010]
In such an embodiment, the lower electrode layer and the upper electrode layer are connected at the exposed portion, and patterning can be performed in a state where there is no potential difference between them.
[0011]
According to a second aspect of the present invention, in the first aspect, the grounding pattern includes the piezoelectric layer and the upper electrode layer extending on the lower electrode layer up to an end of the substrate. The thin film device is characterized.
[0012]
In the second aspect, the upper electrode layer extending to the end of the substrate can be patterned while being grounded.
[0013]
According to a third aspect of the present invention, in the first or second aspect, the trace of the grounding pattern is formed of the piezoelectric layer extending on the lower electrode layer up to an end of the substrate. It is in the thin film device.
[0014]
In the third aspect, the piezoelectric layer is patterned in a state where the upper electrode layer on the piezoelectric layer extending to the end of the substrate is grounded, and then only the unnecessary upper electrode layer is removed, whereby the piezoelectric layer is removed. Patterning can be performed without degrading the characteristics.
[0015]
According to a fourth aspect of the present invention, in any one of the first to third aspects, the substrate is a flow path forming substrate of an ink jet recording head, and the substrate communicates with a nozzle opening on the other surface and has a plurality of partition walls. The multilayer structure formed on the one surface is formed in a region facing the pressure generation chamber on a vibration plate constituting a part of the pressure generation chamber. Further, the present invention resides in a thin film device comprising a piezoelectric active part.
[0016]
In the fourth aspect, the piezoelectric active portion can be patterned without deteriorating the piezoelectric characteristics of the piezoelectric layer.
[0017]
According to a fifth aspect of the present invention, in the fourth aspect, the trace of the grounding pattern is the piezoelectric body that interconnects the piezoelectric active portions provided in regions facing the pressure generation chambers. The thin film device includes a connecting portion including layers.
[0018]
In the fifth aspect, patterning is performed in a state where the respective piezoelectric active portions are grounded via the upper electrode layer on the coupling portion, and the upper electrode layer connecting the respective piezoelectric active portions is removed, thereby obtaining the piezoelectric characteristics. Patterning can be performed without lowering.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on embodiments.
[0030]
(Embodiment 1)
FIG. 1 is an assembled perspective view showing an ink jet recording head according to Embodiment 1 of the present invention, and FIGS. 2A and 2B are a longitudinal direction of one pressure generation chamber and a direction crossing the longitudinal direction. It is a figure which shows each cross-sectional structure.
[0031]
As shown in the drawing, the flow path forming substrate 10 is composed of a silicon single crystal substrate having a plane orientation (110) in this embodiment. As the flow path forming substrate 10, one having a thickness of about 150 to 300 μm is usually used, preferably about 180 to 280 μm, more preferably about 220 μm. This is because the arrangement density can be increased while maintaining the rigidity of the partition between adjacent pressure generating chambers.
[0032]
One surface of the flow path forming substrate 10 is an opening surface, and an elastic film 50 having a thickness of 0.1 to 2 μm made of silicon dioxide previously formed by thermal oxidation is formed on the other surface.
[0033]
On the other hand, two rows 13 of pressure generating chambers 12 partitioned by a plurality of partition walls 11 and two rows of pressure are formed on the opening surface of the flow path forming substrate 10 by anisotropic etching of the silicon single crystal substrate. A reservoir 14 arranged in a substantially U-shape so as to surround three sides of the generation chamber 12 and an ink supply port 15 that connects each pressure generation chamber 12 and the reservoir 14 with a certain fluid resistance are formed. Note that an ink introduction hole 16 for supplying ink from the outside to the reservoir 14 is formed in a substantially central portion of the reservoir 14.
[0034]
Here, in the anisotropic etching, when the silicon single crystal substrate is immersed in an alkaline solution such as KOH, the first (111) plane perpendicular to the (110) plane is gradually eroded and the first (111) ) Surface and an angle of about 70 degrees and the above (110) and a second (111) surface of about 35 degrees appear, and the (111) surface compared to the etching rate of the (110) surface. The etching rate is about 1/180. By this anisotropic etching, precision processing can be performed based on the parallelogram depth processing formed by two first (111) surfaces and two oblique second (111) surfaces. The pressure generating chambers 12 can be arranged with high density.
[0035]
In the present embodiment, the long side of each pressure generating chamber 12 is formed by the first (111) plane and the short side is formed by the second (111) plane. The pressure generation chamber 12 is formed by etching until it substantially passes through the flow path forming substrate 10 and reaches the elastic film 50. Here, the amount of the elastic film 50 that is affected by the alkaline solution for etching the silicon single crystal substrate is extremely small. Each ink supply port 15 communicating with one end of each pressure generation chamber 12 is formed shallower than the pressure generation chamber 12. That is, the ink supply port 15 is formed by etching (half etching) the silicon single crystal substrate halfway in the thickness direction. Half etching is performed by adjusting the etching time.
[0036]
Further, a nozzle plate 18 having a nozzle opening 17 communicating with the side opposite to the ink supply port 15 of each pressure generating chamber 12 is provided on the opening surface side of the flow path forming substrate 10 with an adhesive, a heat-welded film, or the like. It is fixed through. The nozzle plate 18 has a thickness of, for example, 0.1 to 1 mm and a linear expansion coefficient of 300 ° C. or less, for example, 2.5 to 4.5 [× 10 ⁻⁶ / ° C.], or Made of non-rust steel. The nozzle plate 18 entirely covers one surface of the flow path forming substrate 10 on one side, and also serves as a reinforcing plate that protects the silicon single crystal substrate from impact and external force.
[0037]
Here, the size of the pressure generation chamber 12 that applies ink droplet discharge pressure to the ink and the size of the nozzle opening 17 that discharges the ink droplet are optimized in accordance with the amount of ink droplet to be discharged, the discharge speed, and the discharge frequency. The For example, when 360 ink droplets are recorded per inch, the nozzle opening 17 needs to be accurately formed with a diameter of several tens of μm.
[0038]
On the other hand, on the elastic film 50 opposite to the opening surface of the flow path forming substrate 10, a lower electrode film 60 having a thickness of, for example, about 0.5 μm and a piezoelectric film having a thickness of, for example, about 1 μm. 70 and an upper electrode film 80 having a thickness of, for example, about 0.1 μm are laminated by a process described later to constitute a piezoelectric vibrator (piezoelectric element). As described above, a piezoelectric vibrator is provided independently for each pressure generation chamber 12 in the region of the elastic film 50 facing each pressure generation chamber 12. In this embodiment, the lower electrode film 60 is used as a common electrode of the piezoelectric vibrator, and the upper electrode film 80 is used as an individual electrode of the piezoelectric vibrator. However, there is no problem even if this is reversed for the convenience of the drive circuit and wiring. In any case, a piezoelectric active part is formed for each pressure generating chamber 12. In this embodiment, as will be described in detail later, the piezoelectric film 70 and the upper electrode film 80 are formed for each pressure generation chamber 12.
[0039]
And such a flow-path formation board | substrate 10 and the nozzle plate 18 are fixed to the fixing member 20 which has a recessed part holding these.
[0040]
Here, a process of forming the piezoelectric film 70 and the like on the flow path forming substrate 10 made of a silicon single crystal substrate will be described with reference to FIGS.
[0041]
As shown in FIG. 3A, first, an elastic film 50 made of silicon dioxide is formed by thermally oxidizing a silicon single crystal substrate wafer to be the flow path forming substrate 10 in a diffusion furnace at about 1100 ° C.
[0042]
Next, as shown in FIG. 3B, the lower electrode film 60 is formed by sputtering. As a material of the lower electrode film 60, Pt or the like is suitable. This is because a piezoelectric film 70 described later formed by sputtering or a sol-gel method needs to be crystallized by firing at a temperature of about 600 to 1000 ° C. in an air atmosphere or an oxygen atmosphere after the film formation. It is. That is, the material of the lower electrode film 70 must be able to maintain conductivity at such a high temperature and in an oxidizing atmosphere. In particular, when PZT is used as the piezoelectric film 70, the conductivity due to the diffusion of PbO. It is desirable that there is little change in properties, and Pt is preferred for these reasons.
[0043]
Next, as shown in FIG. 3C, a piezoelectric film 70 is formed. Sputtering can be used to form the piezoelectric film 70. In this embodiment, a so-called sol in which a metal organic material is dissolved and dispersed in a solvent is applied, dried, gelled, and further fired at a high temperature. A so-called sol-gel method for obtaining a piezoelectric film 70 made of an oxide is used. As a material of the piezoelectric film 70, a lead zirconate titanate (PZT) -based material is suitable when used for an ink jet recording head.
[0044]
Next, as shown in FIG. 3D, an upper electrode film 80 is formed. The upper electrode film 80 may be made of a highly conductive material, and many metals such as Al, Au, Ni, and Pt, conductive oxides, and the like can be used. In this embodiment, Pt is formed by sputtering.
[0045]
Next, as shown in FIG. 3E, the upper electrode film 80 and the piezoelectric film 70 are patterned so that a piezoelectric vibrator is provided for each pressure generating chamber 12. FIG. 3E shows a case where the piezoelectric film 70 is patterned with the same pattern as the upper electrode film 80. However, as described above, the piezoelectric film 70 does not necessarily need to be patterned. This is because, when a voltage is applied using the pattern of the upper electrode film 80 as an individual electrode, the electric field is applied only between the upper electrode film 80 and the lower electrode film 60, which is a common electrode. This is because it has no effect. However, in this case, in order to obtain the same excluded volume, it is necessary to apply a large voltage, so it is preferable to pattern the piezoelectric film 70 as well. Thereafter, the lower electrode film 60 is patterned to remove unnecessary portions.
[0046]
Here, patterning is performed by forming a resist pattern and then performing etching or the like.
[0047]
The resist pattern is formed, for example, by applying a negative resist by spin coating or the like and performing exposure, development, and baking using a mask having a predetermined shape. Of course, a positive resist may be used instead of the negative resist.
[0048]
Etching is performed until the silicon dioxide film is exposed using a dry etching apparatus such as an ion milling apparatus. Note that after the etching, the resist pattern is removed by using an ashing device or the like.
[0049]
In addition to the ion milling method, a reactive etching method or the like may be used as the dry etching method. It is also possible to use wet etching instead of dry etching, but it is preferable to use dry etching because the patterning accuracy is somewhat inferior compared to the dry etching method and the material of the upper electrode film 80 is limited. .
[0050]
In the present embodiment, as described above, when the piezoelectric active film 320 is formed by patterning the piezoelectric film 70 and the upper electrode film 80, the upper electrode film 80 and the lower electrode film 60 are grounded. That is, as shown in FIG. 4, the grounding extending portion 331 extending from one end portion of the piezoelectric active portion 320 including the piezoelectric film 70 and the upper electrode film 80 facing each pressure generating chamber 12 and these are connected. Connected and provided with a ground connection pattern 332 extending to the end of the flow path forming substrate 10 and connected to a ground portion provided at the end of the wafer to be grounded as will be described later. It is.
[0051]
FIG. 5 schematically shows the entire wafer when patterning the piezoelectric active portion 320 in the grounded state as described above. The above-described ground connection pattern 332 of each flow path forming substrate 10 is connected. A ground connection pattern 340 extending to the ground portion 330 provided at the end of the wafer 1 is provided.
[0052]
Here, the grounding portion 330 is the one in which the lower electrode film 60 and the upper electrode film 80 are short-circuited and grounded. For example, as schematically shown in FIG. 6, the lower electrode film 60 is formed on the elastic film 50 formed on the wafer 1 (FIGS. 6A and 6B), and the piezoelectric layer 60 is formed thereon. For example, when forming by the sol-gel method, the lower electrode film 60 of the outer edge is exposed by rinsing only the outer edge of the wafer 1 (FIG. 6C). Then, by forming the upper electrode film 80 thereon, a short-circuit portion 335 between the lower electrode film 60 and the upper electrode film 80 is formed. Therefore, by grounding via the short-circuit portion 335, both the lower electrode film 60 and the upper electrode film 80 are grounded.
[0053]
When patterning the piezoelectric active part 320 in this way, the upper electrode film 80 and the lower electrode film 60 of each piezoelectric active part 320 are grounded by the grounding part 330 via the grounding pattern. The film 80 is patterned without accumulating charges. Therefore, there is no potential difference between the upper and lower electrodes, and damage to the piezoelectric film 70 during patterning can be reduced.
[0054]
Thereafter, at least the upper electrode film 80 of the ground extension 331 and the ground connection pattern 332 provided in the flow path forming substrate 10 as a ground pattern is removed, and the connection of each piezoelectric active portion 320 is disconnected. In this case, the upper electrode film 80 of the ground extension 331 formed narrower than the piezoelectric active part 320 may not be removed. In addition, the ground extension 331 and the ground connection pattern 332 may be removed up to the piezoelectric film 70. In any case, at least the piezoelectric film 70 of each piezoelectric active part 320 or the trace from which the piezoelectric layer 70 is removed separately from the patterning of the piezoelectric active part 320 extends to the end of the flow path forming substrate 10. Will be. The ground connection pattern 340 formed on the wafer 1 outside each flow path forming substrate 10 is removed at the time of cutting into each flow path forming substrate 10 and thus does not need to be removed.
[0055]
In the above-described example, the ground portion 330 in which the lower electrode film 60 and the upper electrode film 80 are short-circuited is provided to be grounded. However, the ground portion is not necessarily provided when forming a thin film in the wafer 1. There is no need to provide a grounding portion after the thin film is formed. Further, the lower electrode film 60 is not necessarily grounded, and only the upper electrode film 80 may be grounded.
[0056]
Next, a procedure for connecting the lead electrode to the piezoelectric active part 320 formed in this way will be described.
[0057]
First, as shown in FIG. 7A, the insulator layer 90 is formed so as to cover the peripheral portion of the upper electrode film 80 and the side surface of the piezoelectric film 70. A suitable material for the insulator layer 90 is as described above, but in this embodiment, a negative photosensitive polyimide is used.
[0058]
Next, as shown in FIG. 7B, by patterning the insulator layer 90, contact holes 90a are formed in portions facing the communication portions 14. The contact hole 90a is for connecting the lead electrode 100 and the upper electrode film 80, one end of which extends to the connection terminal portion.
[0059]
Next, for example, a lead electrode 100 is formed by forming a conductor such as Cr—Au on the entire surface and then patterning it.
[0060]
The above is the film forming process. After film formation in this way, as shown in FIG. 7C, the silicon single crystal substrate is anisotropically etched with the alkali solution described above to form the pressure generating chamber 12 and the like. In the series of film formation and anisotropic etching described above, a large number of chips are simultaneously formed on a single wafer, and after the completion of the process, one channel-sized flow path forming substrate 10 as shown in FIG. Divide every time.
[0061]
The ink jet head configured in this manner takes in ink from an ink introduction port 16 connected to an external ink supply means (not shown), fills the interior from the reservoir 14 to the nozzle opening 17 with ink, and then external drive circuit (not shown) In accordance with the recording signal from, a voltage is applied between the lower electrode film 60 and the upper electrode film 80 via the lead electrode 100 to cause the elastic film 50 and the piezoelectric film 70 to bend and deform, whereby the pressure generating chamber 12 The internal pressure increases and ink droplets are ejected from the nozzle openings 17.
[0062]
(Embodiment 2)
FIG. 8 is a diagram illustrating a pattern of the piezoelectric active portion according to the second embodiment.
[0063]
In this embodiment, as shown in FIG. 8, when patterning the piezoelectric active part 320 on the flow path forming substrate 10, the piezoelectric active part 320 adjacent to the width direction is connected to the substantially central part in the longitudinal direction. This is basically the same as in the first embodiment, except that the ground connection portion 333 is provided and the ground connection pattern 334 is provided up to the end of the flow path forming substrate 10. Therefore, as described above, it is possible to pattern the piezoelectric active portion 320 while grounding at least the upper electrode film 80 via the ground connection pattern 334, thereby preventing the piezoelectric characteristics of the piezoelectric film 70 from being deteriorated. be able to.
[0064]
Further, each grounding connecting portion 333 is similar to the above-described embodiment in that at least the upper electrode film 80 may be removed after patterning. Therefore, only the upper electrode film 80 of the ground connection portion 333 between the piezoelectric active portions 320 or the trace of the ground pattern from which the upper electrode film 80 and the piezoelectric film 70 are removed remains.
[0065]
With this configuration, as in the first embodiment, there is an effect that damage to the piezoelectric film when patterning the piezoelectric active part can be reduced.
[0066]
(Other embodiments)
While the embodiments of the present invention have been described above, the basic configuration of the ink jet recording head is not limited to that described above.
[0067]
For example, as described above, it is not necessary to provide a pattern for connecting the respective piezoelectric active portions 320 in the flow path forming substrate 10, and the upper electrode films 80 from the respective piezoelectric active portions 320 are respectively formed on the flow path forming substrates. You may make it extend to the edge part of ten. An example of this is shown in FIG. This embodiment is an example in which the piezoelectric film 70 and the upper electrode film 80 of the piezoelectric active part 320 are extended outside the region facing the pressure generation chamber 12 and no contact hole or lead electrode is provided. For each body active part 320, a grounding extension part 335 extending to the end of the flow path forming substrate 10 is provided.
[0068]
Therefore, as described above, it is possible to pattern the piezoelectric active portion 320 while grounding at least the upper electrode film 80 via the ground extension 335, and to prevent the piezoelectric characteristics of the piezoelectric film 70 from deteriorating. can do. In this case, since the upper electrode films 80 of the respective piezoelectric active portions 320 are independent from each other, there is an advantage that it is not necessary to remove the connection pattern. Therefore, in this case, the grounding pattern remains as it is. Of course, only the upper electrode film 80 of the grounding extension 335 or the upper electrode film 80 and the piezoelectric film 70 may be removed. In this case, traces of the grounding pattern remain.
[0069]
Further, for example, as shown in FIG. 10A, when each piezoelectric active part 320 is grounded, a pattern having the same width as the piezoelectric active part 320 is extended to the end of the flow path forming substrate 10. The grounding extension 336 may be provided. The ground extension 336 can be left as it is. However, as shown in FIG. 10B, only the upper electrode film 80 is removed to leave the piezoelectric film 70, and the lead electrode 100 is formed thereon. You may make it provide (FIG.10 (c)).
[0070]
In addition, for example, as shown in FIG. 11A, a grounding extension 337 may be provided at a position shifted in the width direction from the extension of the piezoelectric active part 320. Although the ground extension 337 can be left as it is, as shown in FIG. 11B, only the upper electrode film 80 is removed to leave the piezoelectric film 70, and the extension of the piezoelectric active part 320. A lead electrode 100 may be provided.
[0071]
In any case, with such a configuration, as in the first embodiment, it is possible to reduce the damage to the piezoelectric film when patterning the piezoelectric active portion.
[0072]
In the above-described embodiment, the reservoir 14 is formed together with the pressure generating chamber 12 on the flow path forming substrate 10, but a member that forms a common ink chamber may be provided on the flow path forming substrate.
[0073]
Further, in the above-described embodiment, the connection portion between the upper electrode film and the lead electrode may be provided at any location, and may be any end portion or the central portion of the pressure generating chamber.
[0074]
Further, the example in which the insulator layer is provided between the piezoelectric vibrator and the lead electrode has been described. However, the present invention is not limited to this. For example, without providing the insulator layer, an anisotropic conductive film is provided on each upper electrode. It is good also as a structure which heat-welds and connects this anisotropic conductive film with a lead electrode, and connects using various bonding techniques, such as wire bonding.
[0075]
As described above, the present invention can be applied to other thin film devices in addition to ink jet recording heads having various structures as long as the gist thereof is not contradicted.
[0076]
【The invention's effect】
As described above, in the present invention, when patterning a thin film device, a grounding pattern for grounding the upper electrode film is provided, and the upper electrode film and the lower electrode film are connected. There is no potential difference between the electrodes, and the piezoelectric characteristics of the piezoelectric layer can be prevented from being lowered.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of an ink jet recording head according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the ink jet recording head according to Embodiment 1 of the invention.
FIG. 3 is a diagram showing a thin film manufacturing process according to the first embodiment of the present invention.
FIG. 4 is a diagram showing a pattern of a piezoelectric active part according to the first embodiment of the present invention.
FIG. 5 is a diagram schematically showing a wafer for patterning a piezoelectric active portion.
FIG. 6 is a diagram showing a thin film manufacturing process according to the first embodiment of the present invention.
FIG. 7 is a diagram showing a thin film manufacturing process according to the first embodiment of the present invention.
FIG. 8 is a diagram showing a pattern of a piezoelectric active part according to the first embodiment of the present invention.
FIG. 9 is a diagram showing a pattern of a piezoelectric active part according to another embodiment of the present invention.
FIG. 10 is a view showing a grounding extension according to another embodiment of the present invention.
FIG. 11 is a view showing a grounding extension according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wafer 10 Flow path formation board | substrate 12 Pressure generation chamber 14 Reservoir 15 Ink supply port 16 Ink introduction port 17 Nozzle opening 18 Nozzle plate 20 Fixing member 50 Elastic film 60 Lower electrode film 70 Piezoelectric film 80 Upper electrode film 90 Insulator layer 90a Contact hole 100 Lead electrode 320 Piezoelectric active part 330 Grounding part 331, 335, 336 Grounding extension part 332, 334, 340 Grounding connection pattern 333 Grounding connection part

Claims (2)

In a method for manufacturing a thin film device having a multilayer film structure in which a lower electrode layer, a piezoelectric layer, and an upper electrode layer are sequentially laminated on one surface of a substrate,
Forming the lower electrode layer;
Forming the piezoelectric layer on the lower electrode layer so as to have an exposed portion where at least a part of the lower electrode layer is exposed;
Forming the upper electrode layer connected to the lower electrode layer via at least the exposed portion on the piezoelectric layer, and
A method of manufacturing a thin film device, wherein at least the upper electrode layer is grounded when the piezoelectric layer and the upper electrode layer are patterned by dry etching. 2. The method of manufacturing a thin film device according to claim 1 , wherein at least the upper electrode layer is grounded when the lower electrode layer is patterned by dry etching.

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