Patent Application
20050262691
1. Field of the Invention
The present invention relates to a manufacturing method of a liquid jet head ejecting liquid and, more particularly, to a manufacturing method of an inkjet print head ejecting ink as liquid.
2. Description of the Related Art
An inkjet print head (for instance, refer to Japanese Unexamined Patent Publication No. 2003-159801), which is a liquid jet head, includes: for example, a passage-forming substrate over which a pressure generating chamber communicating with a nozzle orifice and a communicating portion communicating with the pressure generating chamber are formed; a piezoelectric element formed on one plane of the passage-forming substrate; and a reservoir-forming plate which is adhered to the piezoelectric element-side of the passage-forming substrate and which has a reservoir portion constituting a part of a reservoir in association with the communicating portion. Here, the reservoir is formed by allowing the reservoir portion and the communicating portion to communicate with each other through. a penetrated portion penetrating a vibration plate and a multi-layered film provided on the vibration plate. Specifically, portions of the vibration plate and the. multi-layered film which face the communicating portion (reservoir portion) are mechanically punched to form the penetrated portion, whereby the reservoir portion and the communicating portion are allowed to communicate with each other.
However, in the case of forming the penetrated portion by machining, there is the problem that foreign particles such as residues in mechanical fabrication are generated and that the foreign particles get into a passage such as the pressure generating chamber to cause malfunctions in ink ejection and the like. Note that after forming the penetrated portion, by performing cleaning for instance, the foreign particles such as residues in fabrication can be removed to some extent but it is difficult to completely remove them. Further, as a consequence of the machining of the penetrated portion, there arises the problem that cracks and the like are generated at the circumference of the penetrated portion and that malfunctions in ink ejection are caused by the generation of cracks. That is, there arises the following problem: when ink is ejected from the nozzle orifice fully charged with ink under this cracked condition, the cracked portions are separated as fragments, and malfunctions in ink ejection are caused by a blockage of the nozzle orifice due to the fragments.
In the aforementioned Patent Document 1, in order to solve the above-described problems, disclosed is a configuration which can prevent generation of foreign particles by fixing the multi-layered film with a covering film made of resin material. By adopting this configuration, generation of foreign particles may be partially prevented but it is difficult to completely prevent malfunctions in ink ejection caused by the foreign particles.
Note that a problem of this sort surely exits in manufacturing methods of other liquid jet heads ejecting liquids other than ink besides a manufacturing method of an inkjet print head for ejecting ink.
In view of the circumstances described above, an object of the present invention is to provide a manufacturing method of a liquid jet head which can reliably prevent malfunctions in ink ejection, such as a blockage of a nozzle by foreign particles.
According to a first aspect of the present invention to provide a solution of the object described above, a method of manufacturing a liquid jet head includes the steps of: forming a piezoelectric element including a lower electrode, a piezoelectric layer, and an upper electrode on one plane of a passage-forming substrate with a vibration plate interposed therebetween, the passage-forming substrate which is made of a silicon substrate and in which a pressure generating chamber communicating with a nozzle orifice ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed, and removing a region of the vibration plate where the communicating portion is formed, thus forming a penetrated hole; forming a predetermined metal layer on the one plane of the passage-forming substrate over which the piezoelectric element is formed, thus sealing the penetrated hole with the metal layer, and patterning the metal layer in a region corresponding to the piezoelectric element, thus forming a lead electrode extending from the piezoelectric element; adhering a reservoir-forming plate, in which a reservoir portion communicating with the communicating portion to constitute a part of a reservoir is formed, to the one plane of the passage-forming substrate; wet-etching the passage-forming substrate from the other plane thereof until the vibration plate and the metal layer are exposed, thus forming the pressure generating chamber and the communicating portion; and removing a region of the metal layer corresponding to the penetrated hole by etching to allow the reservoir portion and the communicating portion to communicate with each other.
In the case of the first aspect, when forming the reservoir, there is no possibility of generating foreign particles such as residues from fabrication. Thus, the manufacturing method can reliably prevent malfunctions in ink ejection, such as a blockage of a nozzle by foreign particles and the like. Further, when etching the passage-forming substrate, the wrapping-around of etchant into the reservoir-forming plate side through the penetrated hole can also be prevented, and damage and the like to the reservoir-forming plate by the etchant can also be prevented.
A second aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the first aspect, characterized in that the metal layer is removed by performing a wet-etching process in the step of causing the reservoir portion and the communicating portion to communicate with each other.
In the case of the second aspect, the metal layer can be adequately removed in an extremely short time.
A third aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the second aspect, characterized by further including a step of forming a sacrificial layer, which is made of a material having an etching selectivity to the metal layer, in a region corresponding to the peripheral portion of the penetrated hole before the step of forming the metal layer. In addition, the method of manufacturing a liquid jet head is characterized in that the step of causing the reservoir portion and the communicating portion to communicate with each other includes: a step of wet-etching the metal layer through the sacrificial layer, and thereby forming a penetrated portion in the metal layer; and a step of removing the sacrificial layer in a region which is opposed to the penetrated hole.
In the case of the third aspect, adhesiveness of a liquid protective film around a boundary portion between the reservoir portion and the communicating portion is increased in a case where the liquid protective film having liquid resistance is formed in the pressure generating chamber, the reservoir and the like.
A fourth aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the third aspect, characterized in that the sacrificial layer is removed by a dry-etching process.
In the case of the fourth aspect, only the sacrificial layer in the reservoir can be removed. This further increases the adhesiveness of the liquid protective film.
A fifth aspect of the present invention is related to the method of manufacturing a liquid jet head as described in any one of the third aspect and the fourth aspect, characterized in that the sacrificial layer is made of any one of a metal film, an oxide film, a nitride film or an organic film.
In the case of the fifth aspect, use of a predetermined film as the sacrificial layer makes it possible to remove the sacrificial layer in the penetrated holes relatively easily and adequately.
According to a sixth aspect of the present invention, a method of manufacturing a liquid jet head includes the steps of: forming a piezoelectric element including a lower electrode, a piezoelectric layer, and an upper electrode on one plane of a passage-forming substrate with a vibration plate interposed therebetween, the passage-forming substrate which is made of a silicon substrate and in which a pressure generating chamber communicating with a nozzle orifice ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed, and removing a region of the vibration plate where the communicating portion is formed, thus forming a penetrated hole; adhering a reservoir-forming plate, in which a reservoir portion communicating with the communicating portion to constitute a part of a reservoir is formed, to the one plane of the passage-forming substrate; forming a metal layer serving as connection wiring on the reservoir-forming plate, thus sealing the penetrated hole with the metal layer; wet-etching the passage-forming substrate from the other plane thereof until the vibration plate and the metal layer are exposed, thus forming the pressure generating chamber and the communicating portion; and patterning the metal layer to form the connection wiring-, and removing a region of the metal layer facing the penetrated hole by etching to allow the reservoir portion and the communicating portion to communicate with each other.
In the case of the sixth aspect, when forming the reservoir, there is no possibility of generating foreign particles such as residues from fabrication. Thus, the manufacturing method can reliably prevent malfunctions in ink ejection, such as a blockage of a nozzle by foreign particles and the like. Further, when etching the passage-forming substrate, the wrapping-around of etchant into the reservoir-forming plate side through the penetrated hole can be prevented, and damage and the like to the reservoir-forming plate by the etchant can also be prevented.
A seventh aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the sixth aspect, characterized in that, in the step of causing the reservoir portion and the communicating portion to communicate with each other, the metal layer is removed by a wet-etching process.
In the case of the seventh aspect, the metal layer can be adequately-removed in an extremely short time.
An eighth aspect of the present invention is related to the method of manufacturing a liquid jet head as described in any one of the first and sixth aspects, characterized in that, in the step of causing the reservoir portion and the communicating portion to communicate with each other, the metal layer is removed by a dry-etching process.
In the case of the eighth aspect, only the metal layer in regions which are respectively opposed to the penetrated holes can be adequately removed .
A ninth aspect of the present invention is related to the method of manufacturing a liquid jet head as described in any one of the first to eighth aspects, characterized in that any one of gold, aluminum, copper, platinum and iridium is used as a primary material for the metal layer, and that an adhesion layer made of any one of tungsten, nickel and chromium is formed underneath the metal layer.
In the case of the ninth aspect, a lead electrode is formed adequately, and the penetrated holes are securely sealed off with the metal layer.
According to a tenth aspect of the present invention, a method of manufacturing a liquid jet head includes the steps of: forming a piezoelectric element including a lower electrode, a piezoelectric layer, and an upper electrode on one plane of a passage-forming substrate with a vibration plate interposed therebetween, the passage-forming substrate which is made of a silicon substrate and in which a pressure generating chamber communicating with a nozzle orifice ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed, and removing a region of the vibration plate where the communicating portion is formed, thus forming a penetrated hole; adhering a reservoir-forming plate, in which a reservoir portion communicating with the communicating portion to constitute a part of a reservoir is formed, to the one plane of the passage-forming substrate; forming a protective film on the reservoir-forming plate to seal the penetrated hole with the protective film, the protective film being made of a material different from that of the reservoir-forming plate and protecting connection wiring formed on the reservoir-forming plate; wet-etching the passage-forming substrate from the other plane thereof until the vibration plate and the protective film are exposed, thus forming the pressure generating chamber and the communicating portion; and removing a region of the protective film by etching to allow the reservoir portion and the communicating portion to communicate with each other.
In the case of the tenth aspect, when forming the reservoir, there is no possibility of generating foreign particles such as residues from fabrication. Thus, the manufacturing method can reliably prevent malfunctions in ink ejection, such as a blockage of a nozzle by foreign particles and the like. Further, when etching the passage-forming substrate, the wrapping-around of etchant into the reservoir-forming plate side through the penetrated hole can be prevented, and damage and the like to the reservoir-forming plate by the etchant can also be prevented.
An eleventh aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the tenth aspect, characterized in that, in the step of causing the reservoir portion and the communicating portion to communicate with each other, the protective layer is removed by a wet-etching process.
In the case of the eleventh aspect, the metal layer can be removed adequately in an extremely short time.
A twelfth aspect of the present invention is related to the method of manufacturing a liquid jet head as described in the tenth aspect, characterized in that, in the step of causing the reservoir portion and the communicating portion to communicate with each other, the protective layer is removed by a dry-etching process.
In the case of the twelfth aspect, only the metal layer in the regions which are respectively opposed to the penetrated holes can be adequately removed
According to a thirteenth aspect of the present invention, in any one of the tenth to twelfth aspects, in the method of manufacturing a liquid jet head according to the third aspect, a material different from that of the connection wiring is used as the protective film.
In the case of the thirteenth aspect described above, when etching the protective film, simultaneous etching of the connection wiring can be prevented and the protective film can be relatively easily removed.
According to a fourteenth aspect of the present invention, in any one of the tenth to twelfth aspects, in the method of manufacturing a liquid jet head according to the fifth aspect, the protective film is made of any one of an oxide film, a nitride film, an organic film and a metal film.
In the case of the fourteenth aspect described above, the protective film can be relatively easily formed and the penetrated hole can be reliably sealed with the protective film.
Hereinafter, the present invention will be described in detail based on embodiments.
Further, a nozzle plate 20 having drilled nozzle orifices 21 which communicates with the proximity of the opposite end portions of the pressure generating chambers 12 from the ink supply paths 14 is fixed to an opening surface side of the passage-forming substrate 10 with an adhesive agent, a thermal welding film or the like with a mask film 52 interposed therebetween, which is used as a mask for forming the pressure generating chambers 12. Note that the thickness of the nozzle plate 20 is, for example, 0.01 to 1 mm, and is made of glass ceramics, a single crystal silicon substrate, stainless steel or the like having a linear expansion coefficient of, for example, 2.5 to 4.5 (×10−6/° C.) at below 300° C.
Meanwhile, on the plane opposite the opening surface of the passage-forming substrate 10, the elastic film 50 having a thickness of, for instance, about 1.0 μm is formed as described above. On this elastic film 50, an insulation film 51 having a thickness of, for instance, about 0.4 μm is formed. Further, on the insulation film 51, a lower electrode film 60 having, for instance, a thickness of about 0.2 μm, a piezoelectric layer 70 having, for instance, a thickness of about 1.0 μm, and an upper electrode film 80 having, for instance, a thickness of about 0.05 μm are formed to be in a stack by a process described hereinafter, and constitute piezoelectric elements 300. Here, the piezoelectric element 300 refers to a portion including the lower electrode film 60, the piezoelectric layer 70 and the upper electrode film 80. In general, either one of the electrodes of the piezoelectric element 300 is set as a common electrode, and the other electrode thereof and piezoelectric layer 70 are configured by patterning for each of the pressure generating chambers 12. A portion, which is configured of either of the patterned electrodes and the piezoelectric layer 70 and is caused to generate piezoelectric strain by applying a voltage to both electrodes, is referred to as a piezoelectric active portion. In this embodiment, the lower electrode film 60 is set as a common electrode of the piezoelectric elements 300 and the upper electrode film 80 is set as an individual electrode of each piezoelectric element 300. However, depending on a driver circuit and wiring, a reversed positioning thereof can be acceptable without causing any problems. Whichever the case may be, the piezoelectric active portion shall be formed for each pressure generating chamber. Furthermore, here, a combination of the piezoelectric element 300 and a vibration plate which generates displacement driven by this piezoelectric element 300 is referred to as a piezoelectric actuator.
Still further, the upper electrode film 80 of each piezoelectric element 300 described above is electrically connected to a respective lead electrode 90 made of a metal layer of, for instance, gold (Au). A voltage is selectively applied to each piezoelectric element 300 through this lead electrode 90. Though details are described hereinafter, on the insulation film 51 in an area corresponding to the circumference portion of an opening of the communicating portion 13, a metal layer 95 exists in the same layer as that of this lead electrode 90.
The reservoir-forming plate 30 having the reservoir portion 31 constituting at least a part of the reservoir 100 is adhered with an adhesive agent 35 to the surface of the passage-forming substrate 10 where the piezoelectric elements 300 are held. The reservoir portion 31 of the reservoir-forming plate 30 is allowed to communicate with the communicating portion 13 through penetrated holes 50a and 51a provided in the vibration plate, which is, in this embodiment, a combination of the elastic film 50 and the insulation film 51. Thus, the reservoir 100 is formed of this reservoir portion 31 and this communicating portion 13.
In the area of the reservoir-forming plate 30 which is opposed to the piezoelectric elements 300, a piezoelectric element holding portion 32 is disposed. Since the piezoelectric elements 300 are formed in this piezoelectric element holding portion 32, they are protected under the condition that they are virtually free from the influence of the external environment. Note that the piezoelectric element holding portion 32 may be hermetically sealed or may not be hermetically sealed. As to a material for the reservoir-forming plate 30 described above, materials such as glass, ceramics, metal and resin can be listed. However, it is desirable that the reservoir-forming plate 30 be formed of a material having about the same thermal expansion coefficient as that of the passage-forming substrate 10. In this embodiment, a single crystal silicon substrate, which is made of the same material as that of the passage-forming substrate 10, is used.
Further, on the reservoir-forming plate 30, connection wiring 200 formed in a predetermined pattern is disposed. On this connection wiring 200, a driver IC 210 for driving the piezoelectric elements 300 is mounted. The driver IC 210 is electrically connected to the tip portion of each lead electrode 90 via drive wiring 220. Here, the lead electrodes 90 are extended from the piezoelectric elements 300 to the area outside of the piezoelectric element holding portion 32.
Furthermore, a compliance plate 40 made of a sealing film 41 and a clamping plate 42 is adhered to the area of the reservoir-forming plate 30 which corresponds to the reservoir portion 31. The sealing film 41 is made of a flexible material having low rigidity (for instance, a polyphenylene sulfide (PPS) film of 6 μm thickness). With this sealing film 41, one end of the reservoir portion 31 is sealed. Further, the clamping plate 42 is formed of a hard material such as a metal (for instance, stainless steel (SUS) of 30 μm thickness). Since the area of this clamping plate 42 which faces to the reservoir 100 forms an opening portion 43 in which the clamping plate 42 is completely removed in the thickness direction, one end of the reservoir 100 is sealed only with the sealing film 41 having flexibility.
In the inkjet print head of this embodiment described above, ink is taken in from external ink supply means (not shown) ; after filling with ink the internal part from the reservoir 100 to the nozzle orifice 21, a voltage is applied between the lower electrode film 60 and the upper electrode films 80 respectively corresponding to the pressure generating chambers 12, in accordance with a print signal supplied from the driver IC 210; and the piezoelectric element 300 and the vibration plate deform by being bent, whereby an inside pressure of each pressure generating chamber 12 is increased and ink is ejected out of the nozzle orifices 21.
Hereinbelow, the manufacturing method of the inkjet print head shown above is described with reference to
Next, as shown in
Subsequently, as shown in
Note that, as to a material for the piezoelectric layer 70 constituting the piezoelectric elements 300, for example, a ferroelectric-piezoelectric material such as lead zirconate titanate (PZT), or relaxor ferroelectrics such as the ferroelectric-piezoelectric material listed above doped with metal such as niobium, nickel, magnesium, bismuth or yttrium is used. The composition of the piezoelectric layer 70 may be selected as appropriate considering the characteristics, usage and the like of the piezoelectric elements 300. For instance, PbTiO3 (PT), PbZrO3 (PZ), Pb(ZrxTi1−x)O3 (PZT), Pb (Mg1/3Nb2/3) O3—PbTiO3 (PMN-PT), Pb (Zn1/3Nb2/3) O3—PbTiO3 (PZN-PT), Pb (Ni1/3Nb2/3) O3—PbTiO3 (PNN-PT), Pb (In1/2Nb1/2) O3—PbTiO3 (PIN-PT), Pb (Sc1/3Ta2/3) O3—PbTiO3 (PST-PT), Pb (Sc1/3Nb2/3) O3—PbTiO3 (PSN-PT), BiScO3—PbTiO3 (BS-PT), or BiYbO3—PbTiO3 (BY-PT) can be selected.
Further, a forming method of the piezoelectric layer 70 is not specifically limited. However, for example, in this embodiment, the piezoelectric layer 70 is formed using a well-known sol-gel method: a sol in which a metal-organic substance is dissolved and diffused in a catalytic agent is applied and dried to produce a gel, and further the gel is baked at a high temperature to obtain the piezoelectric layer 70 made of a metal-oxide substance.
Next, as shown in
Here, as to the primary material for the metal layer 95, there is no particular restriction if the material has a relatively high conductivity, but it is preferable to use gold (Au), aluminum (Al), copper (Cu), platinum (Pt) or iridium (Ir) for instance. In addition, when the metal layer 95 described above is formed, it is preferable that an adhesion layer for securing adhesiveness of the metal layer 95 (lead electrode 90) be formed beforehand underneath the metal layer 95. As a material for the adhesion layer, for example, tungsten (W), nickel (Ni), chromium (Cr) and the like can be listed. However, it is preferable that particularly titanium-tungsten (TiW), nickel-chromium (NiCr) or the like be used. Incidentally, although the penetrated holes 50a and 51a are designed to be sealed with the metal layer 95 in the case of this embodiment, the penetrated holes 50a and 51a may be sealed with only the adhesion layer in a case where the adhesion layer is formed underneath the metal layer 95.
Next, as shown in
Next, as shown in
At this moment, since the penetrated holes 50a and 51a are sealed with the metal layer 95, the etchant will not flow into the side where the wafer 130 for a reservoir-forming plate is located, through the penetrated holes 50a and 51a. Because of this, the etchant will not come into contact with the connection wiring 200 which is deposited on the surface of the wafer 130 for a reservoir-forming plate. Thus, occurrence of malfunctions such as breaking of wiring can be prevented. Furthermore, there is no possibility that the wafer 130 for a reservoir-forming plate is etched with the etchant intruded into the reservoir portion 31.
Note that in the case of forming the pressure generating chambers 12 described above, the surface of the wafer 110 for a reservoir-forming plate, which is opposite from the surface having the wafer 110 for a passage-forming substrate, may be further sealed with a sealing film made of an alkali-proof substance, such as PPS (polyphenylene sulfide) or PPTA (poly-paraphenylene terephthalamide). By doing so, malfunctions such as a break in wiring disposed on the surface of the wafer 130 for a reservoir-forming plate can be prevented with much higher certainty.
Next, as shown in
Further, after forming the reservoir 100 as described above, as shown in
As described above, in this embodiment, the penetrated holes 50a and 51a are sealed with the metal layer 95 which is in the same layer as the lead electrodes 90, and the reservoir portion 31 and the communicating portion 13 are allowed to communicate with each other by removing this metal layer 95 ultimately by use of etching. Due to this series of processing, there is no possibility of generating foreign particles such as residues from fabrication unlike conventional machining. Therefore, it is ensured to reliably prevent malfunctions in ink ejection such as a blockage in a nozzle caused by residues from fabrication, by preventing residues in fabrication from remaining in ink flowing passages such as the pressure generating chambers 12 and the communicating portion 13. Furthermore, in the case of this embodiment, since the metal layer 95 is designed to be removed by the wet-etching process, the metal layer 95 can be adequately removed in an extremely short time.
It should be noted that, although the metal layer 95 is removed by the wet-etching process in the case of this embodiment, a process for removing the metal layer 95 is not specifically limited to the wet-etching, and that the metal layer 95 may be removed by a dry-etching process. Since the metal layer 95 is made of gold (Au) or the like as described above, the metal layer 95 can be adequately removed by an ion-milling process or the like Furthermore, as described above, in a case where the adhesion layer made, for example, of titanium-tungsten (TiW) or the like is formed underneath the metal layer 95, the adhesion layer may be removed, first of all, by a plasma dry-etching process using a fluoro carbon-based etching gas, for example, carbon tetrafluoride (CF4), and thereafter the metal layer 95 may be removed by the ion-milling process.
Specifically, first, as in embodiment 1, piezoelectric elements 300 are formed on a wafer 110 for a passage-forming substrate, and then, the penetrated holes 50a and 51a are formed. Furthermore, the lead electrodes 90 are formed (refer to FIGS. 3A to 4A). Incidentally, in the case of this embodiment, the penetrated hole 51a in an insulation film 51 is formed in such a way that an opening area of the penetrated hole 51a in the insulation film 51 is larger than that of the penetrated hole 50a in an elastic film 50 (see
Next, as shown in
In this respect, it suffices that the sacrificial layer 140 were formed of a material having an etching selectivity to the metal layer 95 which is formed on the sacrificial layer 140 in a step, which will be described later. It is preferable that the sacrificial layer 140 be made, for example, of a metal film, an oxide film, an organic film or the like. In addition, it is preferable that the sacrificial layer 140 be removed by a dry-etching process. For this reason, it is preferable that, specifically, a material such as copper (Cu), chromium (Cr) or silicon nitride (SiN) be used. Incidentally, in the case of this embodiment, silicon nitride is used as the material for the sacrificial layer 140.
Subsequently, as shown in
Thereafter, the wafer 110 for a passage-forming substrate and a wafer 130 for a reservoir-forming plate are bonded to each other, and thus the wafer 110 for a passage-forming substrate is processed with a predetermined thickness, as in the case of embodiment 1 (see
Then, the metal layer 95 is wet-etched through an orifice 140a in the sacrificial layer 140, and thereby a penetrated portion 95a is formed in the metal layer 95, as shown in
Note that, while the metal layer 95 is being etched, the metal layer 95 is etched by approximately several ,,m in the plane direction (side-etched), in addition to be etched in the thickness direction. For this reason, the penetrated portion 95a in the metal layer 95 is formed so as to be slightly larger than the orifice 140a in the sacrificial layer 140.
In addition, when the metal layer 95 is intended to be removed by the wet-etching process in this manner, it is preferable that the metal layer 95 be protected by means of adhering a thermal release sheet or the like to an entire surface of the wafer 130 for a reservoir-forming plate. The thermal release sheet is, for example, a sheet whose base material is polyester film, and the thermal release sheet can be easily released off by means of heating the thermal release sheet to a predetermined temperature (thermal release temperature). In the case of this embodiment, the thermal release sheet which has a thermal release temperature lower than, for example, 140° C. is used. Use of such a thermal release sheet makes it possible to prevent occurrence of problems, including breaking of wiring provided to the surface of the wafer 130 for a reservoir-forming plate. In addition, such a thermal release sheet can be released off merely by means of heating.
Subsequently, the sacrificial layer 140 is removed as shown in
Thence, an ink protective film 150 made of an ink-resistant (liquid-resistant) material, for example tantalum pentoxide or the like, is formed in internal surfaces respectively of a pressure generating chamber 12, an ink supply path 14 and the reservoir 100 by a CVD process or the like.
In this respect, the penetrated portion 95a is formed in the metal layer 95 through the sacrificial layer 140 in the aforementioned manner, and the sacrificial layer 140 is removed by the dry-etching process, in the case of this embodiment. Accordingly, the metal layer 95 is left remaining in a state of extending out towards the inside of the reservoir 100. For this reason, adhesiveness of the ink protective film 150 is increased while the ink protective film 150 is being formed on the inner surface of the reservoir 100. Accordingly, the ink protective film 150 can be adequately formed on the entire internal surface of the reservoir 100.
Additionally, according to such a manufacturing method, ejection problems, such as blockage of a nozzle due to residues in fabrication which have remained in the ink path including the pressure generating chamber 12 and the reservoir 100, can be securely prevented from occurring, as in the case of embodiment 1.
Specifically, first of all, a piezoelectric element 300 is formed on a wafer 110 for a passage-forming substrate, and penetrated holes 50a and 51a are formed thereon, as in the case of embodiment 1. In addition, a lead electrode 90 is formed thereon (see
Next, as shown in
Next, as shown in
After forming the pressure generating chambers 12, the communicating portion 13 and the like as described above, as shown in
With this embodiment described hereinbefore, malfunctions in ink ejection such as a blockage in a nozzle caused by residues in fabrication remaining in ink flowing passages such as the pressure generating chambers 12 and the communicating portion 13, can be surely prevented as in the case of embodiment 1.
Specifically, first, as in embodiment 1, piezoelectric elements 300 are formed on a wafer 110 for a passage-forming substrate, and then, the penetrated holes 50a and 51aare formed. Furthermore, the lead electrodes 90 are formed (refer to
Next, as shown in
Next, as shown in
After forming the pressure generating chambers 12, the communicating portion 13 and the like as described above, as shown in
With this embodiment described hereinbefore, it is needless to say that malfunctions in ink ejection such as a blockage in a nozzle caused by residues in fabrication remaining in ink flowing passages such as the pressure generating chambers 12 and the communicating portion 13 can be surely prevented as in the case of embodiment 1. Further, by forming the protective film 230 with a different material from that of the wafer 130 for a reservoir-forming plate, the protective film 230 can be easily removed at the time of etching the protective film 230, without etching the wafer 130 for a reservoir-forming plate. Furthermore, similarly, by forming the protective film 230 with a different material from that of the connection wiring 200, the protective film 230 can be easily and favorably removed at the time of etching the protective film 230, without removing the connection wiring 200. Still further, it can be quoted that the protective film 230 is preferably made of a nitride film, but the material to be used needs to be different from that of the mask film 52. In other words, in the example described hereinbefore, SiN is used for the mask film 52. Therefore, it is possible to consider that, as to the material for the protective film 230, a metal such as Nichrome (Registered trademark) can be used.
Hereinbefore, several embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments. For example, in the embodiments described above, the piezoelectric elements 300 are formed after forming the penetrated holes 50a and 51a. But the other way around, the penetrated holes 50a and 51a can be formed after forming the piezoelectric elements 300. Further, in the embodiments described above, the inkjet print heads are described as an exemplary case of liquid jet heads. However, the present invention can be widely applied to various types of liquid jet heads in general, and can certainly be also applied to manufacturing methods of liquid jet heads which eject a various sorts of liquids besides ink. As other types of liquid jet heads, listed are the following heads: for example, various types of print heads used for image recording apparatuses, such as printers; color material ejection heads used for manufacturing color filters for liquid crystal displays and the like; electrode material ejection heads used for forming electrodes for organic EL displays, FEDs (Field Emission Displays), and the like; and living organic material ejection heads used for manufacturing bio-chips.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-153840 | May 2004 | JP | national |
| 2004-265244 | Sep 2004 | JP | national |
| 2004-287893 | Sep 2004 | JP | national |
