JP3311198B2 - Substrate for inkjet head, inkjet head, inkjet pen, and inkjet device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium (hereinafter, typically referred to as "paper") containing paper, plastic sheet, cloth, article, etc. By discharging ink (typically referred to as "ink"), recording, printing, etc. (hereinafter, typically referred to as "recording") of characters, symbols, images, and the like (hereinafter, typically referred to as "images") are performed. A base for configuring an inkjet head to be performed, an inkjet head configured using the base,
An inkjet pen including an ink storage unit for storing ink supplied to the inkjet head;
And an ink jet device to which the ink jet head is mounted. The ink-jet pen referred to in the present invention includes both a cartridge form in which the ink-jet head and the ink storage section are integrated and a form in which they are detachably combined separately. This ink-jet pen is detachable from mounting means such as a carriage on the apparatus main body side. In addition, the ink jet device referred to in the present invention is provided integrally or separately as an output terminal of an information processing device such as a word processor or a computer, and has a copying device combined with an information reading device and the like, and an information transmitting / receiving function. Facsimile machines, machines that print on fabric, etc.

[0002]

2. Description of the Related Art An ink jet apparatus has a feature that high-speed recording of a high-definition image can be performed by discharging ink as fine droplets from a discharge port at a high speed. In particular, a method of using an electrothermal converter as an energy generating means for generating energy used for discharging ink and discharging ink using foaming of ink generated by thermal energy generated by the electrothermal converter is used. The ink jet device is excellent in device performance such as high definition of an image, high-speed recording, and downsizing of a head and a device. The market demands for the performance of these devices are increasing year by year, and various improvements of ink jet devices are being promoted accordingly.

[0003] Various proposals have been made for such improvement measures. S. Patent N
o. 4,458,256. This U. S. P. For example, FIG. In 11, a return portion of an electrode for applying electric energy to a heat generating portion (hereinafter, also referred to as a "heater") of a resistor constituting an electrothermal converter is used as a common electrode, and the common electrode is used as an insulating layer. 2 shows a configuration provided as a conductive layer underneath. According to this configuration, when a plurality of heaters are arranged and designed, there is no hindrance due to the return portion of the electrode, so that the plurality of heaters can be arranged closer to each other than in the related art. Since the ink path communicating with the ejection port is provided corresponding to the heater, it is possible to achieve a higher density arrangement of the ink path. If the ink paths can be arranged at a higher density, the ejection ports can be arranged at a higher density, so that a higher definition image can be obtained. Further, since the arrangement of the ink paths at a higher density leads to a saving of the space of the substrate, a further downsizing of the head can be achieved.

[0004] Japanese Utility Model Publication No. 6-28272 also discloses a configuration in which a metal layer serving as a common electrode is provided below a heating resistor layer via an undercoat layer. As a material for such a metal layer, tantalum, molybdenum, tungsten and the like are mentioned.

However, as a result of the study by the present inventors, it has been found that the above-described ink jet head has the above-mentioned various features, but has the following problems. That is, in the ink jet head having the above-described configuration, there is a problem that the life of the ink jet head may be shorter than expected, or there may be a case where the ejection performance is reduced while the ink is continuously ejected. .

[0006]

As a result of further studies by the present inventors to determine the cause, the following has been found. That is, when the common electrode is made of aluminum or the like, a stress concentration region called a “hillock” that protrudes in a convex shape may be generated on the surface of the common electrode under the influence of heat. In particular, the temperature around the lower common electrode of the heater may instantaneously reach near the melting point of the metal material forming the common electrode due to the high heat generated by the heater. Hillocks further grow or new hillocks are generated due to stress concentration at the common electrode. Since these hillocks sequentially extend upward through various layers, a convex portion having a height of, for example, about 2 μm is formed on the foaming surface on the heater. Due to the effects of large-scale pressure fluctuations and thermal stress on the foaming surface called "cavitation" due to repeated bubbling in the ink path, areas where the film quality of the step portion (corner) of the convex portion of the foaming surface weakens are concentrated In the event of severe damage, the ink will eventually penetrate from such a location and cause electrical contact, leading to the disconnection of the resistor. As a result, the ink jet head breaks down and its life is unexpectedly shortened. In addition, the strain that appears as a convex portion on the foaming surface increases in accordance with the growth of the hillock, and the adverse effect on the foaming phenomenon gradually increases. As a result, the ejection performance decreases as the ink is continuously ejected.

As a result of the present inventors' investigation into the cause of the above-mentioned problem, although there is still an unexpected phenomenon, the following has also been found as a cause of the problem. In other words, actual fairness 6-282
When the common electrode is made of tantalum, molybdenum, tungsten, or the like as in No. 72, since the resistivity of these metals is relatively large, the heat generated by these metals themselves as ink continues to be ejected is increased. In addition to the heat generated by the heater, the heat is gradually accumulated in the head. Due to the effect of the heat thus accumulated, it becomes gradually difficult to control the heat on the foaming surface and maintain a normal foaming phenomenon. As a result, the discharge performance is reduced while the discharge of the ink is continued. This problem becomes more remarkable because the smaller the distance between heaters and the higher the density, the easier it is for heat to accumulate. In addition, this problem becomes more remarkable because the faster the inkjet head is driven, the more heat is easily accumulated.

An object of the present invention is to solve the above-mentioned problems and to provide a base for forming an ink jet head having a low failure rate and a long life, and an ink jet head formed using the base. It is.

Another object of the present invention is to provide a base for forming an ink jet head capable of performing good ink ejection over a long period of time, and an ink jet head formed using the base.

Still another object of the present invention is to provide a base for forming an ink jet head in which a plurality of discharge ports are arranged at a high density and capable of recording a high-definition image at a high speed, and using the base. It is an object of the present invention to provide a configured inkjet head.

Still another object of the present invention is to provide a substrate for forming a miniaturized ink jet head which saves space on the substrate and an ink jet head formed using the substrate.

It is still another object of the present invention to provide a substrate for forming an ink jet head which is reduced in cost by saving space on a substrate made of a relatively expensive material such as single crystal silicon, and the substrate. And an ink-jet head configured using the same.

Still another object of the present invention is to provide an ink-jet pen including an ink storage section for storing ink supplied to the above-described excellent ink-jet head, and an ink-jet apparatus to which such an ink-jet head is mounted. It is to be.

[0014]

SUMMARY OF THE INVENTION One aspect of the present invention provides
Heat generation including a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers generates heat energy used for discharging ink. And a substrate on which the electrothermal converter is provided, wherein one of the pair of electrode layers is below the heat generating portion. The electrode layer located on the lower side of the heat generating portion has a laminated structure composed of a plurality of layers, and at least one of the layers closest to the heat generating portion has a pressure of 1 atm. Wherein the substrate has a melting point of 1500 ° C. or higher.

Another embodiment of the present invention includes a resistor layer and a pair of electrode layers connected to the resistor layer, and the resistor layer located between the pair of electrode layers ejects ink. And a substrate on which the electrothermal converter serves as a heat generating portion for generating heat energy used for generating the thermal energy, and a substrate provided on the electrothermal converter. An ink path is provided, and an ejection port for ejecting ink is provided in communication with the ink path, wherein one of the pair of electrode layers is located below the heating section. Passing through the side, the electrode layer located on the lower side of the heat generating portion has a laminated structure consisting of a plurality of layers,
At least the layer closest to the heat generating portion among the plurality of layers is made of a metal having a melting point of 1500 ° C. or more at 1 atm.

Still another embodiment of the present invention includes a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers ejects ink. An electro-thermal converter serving as a heat-generating portion that generates thermal energy used for performing the heat-generating process, and a substrate on which the electro-thermal converter is provided. An ink path is arranged correspondingly, an ink jet head provided with an ejection port for ejecting ink in communication with the ink path, and an ink storage section for storing ink supplied to the ink path. An ink-jet pen having a laminated structure in which one of the pair of electrode layers passes below the heat-generating portion, and the electrode layer located below the heat-generating portion is composed of a plurality of layers. And less of the plurality of layers Both side closest layer to the heating unit is an ink jet pen, wherein the melting point of 1 atm is made of a metal is more than 1500 degrees Celsius.

Still another embodiment of the present invention includes a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers ejects ink. An electro-thermal converter serving as a heat-generating portion that generates thermal energy used for performing the heat-generating process, and a substrate on which the electro-thermal converter is provided. An ink path is provided correspondingly, an ink jet head having an ink jet head provided with an ejection port for jetting ink in communication with the ink path, and mounting means for mounting the ink jet head. Wherein one of the pair of electrode layers passes under the heat-generating portion, and the electrode layer located below the heat-generating portion has a laminated structure including a plurality of layers; At least the source The closest layer to the parts of an ink jet apparatus characterized by melting point at 1 atm is made of a metal is more than 1500 degrees Celsius.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present inventors have found that the above-mentioned problem can be solved by forming the lower electrode of the heater in a laminated structure composed of a plurality of layers and forming at least the uppermost layer thereof with a refractory metal. I got The present invention is based on this finding,
It has been made through intensive studies by the present inventors. This finding is specifically as follows. That is, the lower electrode of the heater, which is most susceptible to the heat generated by the heater, has a laminated structure including a plurality of layers, and the layers function complementarily. The lower layer of the plurality of layers is formed of a normal electrode material having high electric conductivity. Thereby, a good electrode with little power loss can be obtained. At least the uppermost layer of the plurality of layers is formed of a high melting point metal. This layer diffuses heat to mitigate its effects, and itself functions as a layer unaffected by heat. As a result, generation of hillocks is prevented or suppressed, and formation of a convex portion on the foamed surface is also prevented or suppressed.

As the material constituting the electrode portion other than the refractory metal layer according to the present invention, a material usually used as an electrode material in the art can be used as it is. Metals with melting points below 1500 degrees Celsius are preferred. For example, Al, Cu, Al
-Si-based alloy, or Al-Cu-based alloy is preferable,
Among them, Al is the best in overall characteristics. In this specification, “metal” is used as a term including “metal element” and “alloy”, but includes a pure metal containing no impurities and a metal containing impurities.

As the high melting point metal according to the present invention, a metal having a melting point of not less than 1500 degrees Celsius at 1 atm is preferable, and a metal having a melting point of not less than 2500 degrees Celsius is more preferable. For example, Ta, W, Cr, Ti, Mo, an alloy composed of two or more metal elements selected from these metal elements, an alloy containing a metal element selected from these metal elements, or the like is preferable. Among them, Ta is most suitable.

In the present invention, if the refractory metal layer is formed to have a compressive stress, stress concentration at the lower electrode of the heater is more unlikely to occur, and hillock formation is further prevented. Very preferred. The value of the compressive stress is preferably 1 × 10 ⁷ dyn / cm ² or more and 1 × 10
¹² dyn / cm ² or less, optimally 1 × 10 ⁹ dyn / cm
^{It is 2} or more and 1 × 10 ¹⁰ dyn / cm ² or less.

FIG. 1 is a schematic sectional view of a main part of an ink jet head according to an embodiment of the present invention, which is cut from above a heater. FIG. 2A is a schematic cross-sectional view of a main part of the inkjet head of FIG. 1 taken along line AA ′, and FIG. 2B is a schematic view of a main part of the inkjet head of FIG.
It is the schematic cross section cut | disconnected by the B 'line.

The ink jet head according to the present embodiment is provided with a plurality of discharge ports 1101. Discharge port 1
Heating portion (heater) 110 of an electrothermal converter that generates energy used to discharge ink from 101
2 are provided for each ink path 1108 communicating with each ejection port. The electrothermal converter includes a resistor layer 1103 including a heat generating portion 1102 and electrodes for supplying electric energy to the resistor layer. The electrode is an individual electrode layer 1110
a, the connection electrode layer 1110d, and the common electrode layer. The common electrode layer has a multilayer structure including an upper electrode layer 1110c and a lower electrode layer 1110b, and is provided in a solid shape without being separated individually.

On the substrate 103, the above-mentioned common electrode layer having a multilayer structure is formed via a lower insulating layer 1111. Upper insulating layer 111 provided on the common electrode layer
In a predetermined portion of No. 2, a through hole 1105 is formed by patterning. On the upper insulating layer 1112, a resistor layer 1103, an individual electrode layer 1110a, and a connection electrode layer 1110d are formed by patterning. The connection electrode layer 1110d has a through hole 1105
Are connected to a common electrode layer via a resistor layer 1103.

Resistor layer 1103, individual electrode layer 1110a
The lower protective layer 1113 and the upper protective layer 1114 cover the connection electrode layer 1110d. The inkjet head substrate 104 according to the present embodiment includes the substrate 103 and the various thin layers described above formed thereon.

Each ink passage 1108 is partitioned by a road wall member 1109. The end of the ink path 1108 opposite to the ejection port 1101 communicates with the common ink chamber 1106. In the common ink chamber 1106, ink supplied from an ink tank for storing ink is temporarily stored. The ink supplied to the common ink chamber 1106 is guided to each ink path 1108, and forms a meniscus at the ejection port 1101 and is held. By selectively driving the electrothermal transducer to generate heat, film boiling occurs in the ink and bubbles are generated. Ink is ejected from the ejection port 1101 in accordance with the growth of the bubble.

In the ink jet head according to the present embodiment, the upper electrode layer 1110c among the plurality of layers constituting the common electrode layer is formed of a high melting point metal. According to such a configuration of the ink jet head substrate, the heat generating portion 1
Heating portion 11 that is most susceptible to the heat generated by 102
02 at least in the uppermost layer (the upper electrode layer 11
Since 10c) is formed of a high-melting-point metal, the high-melting-point metal layer diffuses heat, softens its influence, and functions as a layer that is not itself affected. Therefore, generation of hillocks can be prevented or suppressed. According to this, since the generation of hillocks is prevented or suppressed, it is possible to prevent or suppress the formation of a convex portion on the foamed surface.

Further, since the return portion of the electrode is provided in common as a wide conductive layer, there is an advantage that the voltage drop can be suppressed as compared with the case where the return portion of the electrode is provided individually for each heater.

In order to manufacture the ink jet head substrate according to the present embodiment, a film forming technique used for manufacturing a semiconductor or the like can be appropriately used. For example, an inorganic material such as silicon oxide or silicon nitride is formed on a substrate 103 made of single crystal silicon or the like by a known film formation technique to form a lower insulating layer 1111. And Next, A is used as the lower electrode layer.
For example, a material layer of a common electrode layer having a multi-layer structure is formed by sequentially forming a high melting point metal such as Ta as an upper electrode layer by continuous sputtering, for example. At this time, it is preferable to form the refractory metal layer to have a compressive stress by adjusting the argon pressure of the continuous sputtering. Next, a plurality of material layers of the common electrode layer are simultaneously patterned by, for example, dry etching to form a common electrode layer. In FIG. 1, this pattern has a broad solid shape. The method for manufacturing the ink jet substrate after the step of forming the upper insulating layer 1112 may be similarly performed using a known film forming technique.

FIG. 5A is a schematic cross-sectional view of the main part of an ink-jet head according to another embodiment of the present invention viewed from the same direction as FIG. 1, and FIG. 5B is a schematic cross-sectional view viewed from the same direction as FIG. 2A. It is.

This embodiment is different from the previous embodiment in that
An electrode provided below the upper insulating layer 1112 is not a solid conductive layer, but is a separate and independent electrode corresponding to each heat generating portion 1102. This electrode also has a multilayer structure including an upper electrode layer 1110f and a lower electrode layer 1110e, and the upper electrode layer 1110f is formed of a high melting point metal. According to such a configuration of the inkjet head substrate, at least the uppermost layer (upper electrode layer 1110f) of the lower electrode of the heat generating portion 1102, which is most susceptible to the heat generated by the heat generating portion 1102, is formed of a high melting point metal. Therefore, the refractory metal layer diffuses heat to relieve the influence and functions as a layer which is not affected by itself. Therefore, generation of hillocks can be prevented or suppressed. According to this, since the generation of hillocks is prevented or suppressed, it is possible to prevent or suppress the formation of a convex portion on the foamed surface.

Further, in the ink jet head according to the present embodiment, since the lower electrodes are independent of each other, the heat generated by the heat generating portion 1102 adversely affects the adjacent heat generating portion via the lower electrode. Does not occur. Also, there is an effect that energy loss due to diffusion of heat via the lower electrode is suppressed.

The substrate for an ink jet head according to the present embodiment is manufactured by changing the pattern from that of the previous embodiment so that the material layers of the electrode layers are separated and independent when patterned. Just do it.

FIG. 6A is a schematic perspective view showing an ink jet head according to one embodiment of the present invention. FIG. 6B is a schematic cross-sectional view of the inkjet head shown in FIG. 6A taken along line CC ′. Note that FIG. 1A shows a main part of a schematic cross-sectional view of the inkjet head shown in FIG. 6A taken along the line DD ′.

The ink-jet head 12 is provided on the top plate 10 made of resin with respect to the ink-jet head base 104.
5 is formed by pressure bonding using an elastic member such as a spring. The top plate 105 includes a discharge port plate 1104 provided with a discharge port 1101 and a road wall member 1109.
Are integrally formed. A common ink chamber 1106 is provided inside the top plate 105. The common ink chamber 1106 is supplied with ink from an ink tank for storing ink via a supply port 107. The ink supplied to the common ink chamber 1106 is supplied to each ink path 11
08 to form a meniscus at the discharge port 1101 and hold it. By selectively driving the electrothermal transducer to generate heat, a state change including film boiling occurs in the ink and bubbles are generated. Ink is ejected from the ejection port 1101 in accordance with the growth of the bubble.

FIG. 7 is a schematic perspective view showing a main part of an ink jet apparatus 15 equipped with a cartridge type ink pen incorporating the ink jet head shown in FIGS. 6A and 6B.

The lead screw 256 rotates via the driving force transmission gears 262 and 260 in conjunction with the forward / reverse rotation of the drive motor 264. Spiral groove 2 of lead screw 256
A pin (not shown) that engages with the carriage 55
, The carriage 16 is reciprocated in the directions of the arrows a and b in accordance with the rotation of the lead screw 256. A paper pressing plate 253 presses the paper 272 against the platen 251 over the moving direction of the carriage 16. Photocouplers 258 and 259 serve as home position detecting means for confirming the presence of the lever 257 of the carriage 16 in this area and switching the rotation direction of the motor 264, for example. Reference numeral 11 denotes a cartridge type ink-jet pen provided integrally with an ink tank. Reference numeral 265 denotes a cap for capping the ink discharge port of the ink-jet pen.
5 is supported by the support member 270. Reference numeral 273 denotes a suction unit for performing suction from the ink discharge port via the cap 265, and performs suction recovery processing of the head via the opening 271 of the cap 265. Reference numeral 266 denotes a blade for cleaning the surface provided with the ink discharge ports, and reference numeral 268 denotes a member for moving the blade 266 in the front-rear direction. These are supported by the main body support plate 267.

[0038]

EXAMPLE 1 A plurality of substrates for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured as follows. A 1.5 μm-thick lower insulating layer 1111 made of silicon oxide was formed over a substrate 103 made of single crystal silicon by thermal oxidation. On top of that 55
A 00 layer of Al layer followed by a 2000 layer of Ta layer,
The Ta layer was formed while adjusting the argon pressure during sputtering to 1.8 Pa so that the compressive stress of the Ta layer was 5 × 10 ⁹ dyn / cm ² . The Al layer and the Ta layer are made of BCl ₃ (46%) and Cl ₂ (3
Simultaneous patterning by dry etching using a mixed gas of 6%) and N ₂ (18%) makes it possible to form a lower electrode layer 1110b made of Al as shown in FIGS. Electrode layer 1110
c was obtained. Next, a 1.4 μm-thick upper insulating layer 1112 made of silicon oxide was formed by a plasma CVD method. Etching was performed using ammonium fluoride to form a through hole 1105 for contact.
A tantalum nitride layer having a thickness of 600 ° was formed by sputtering, and was patterned by etching to obtain a resistor layer 1103 having the shape shown in FIG. A pure Al layer having a thickness of 5500 ° is formed thereon by sputtering, and is patterned by etching to form an individual electrode 1110a and a connection electrode 111 having the shape shown in FIG.
0d was obtained. Further, a lower protective layer made of silicon oxide and having a thickness of 1.0 μm was formed by a plasma CVD method.
2300 made of Ta by sputtering
A thick upper protective layer 1114 was formed. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. This inkjet head 12
The arrangement density of the discharge ports 1101 is 16 pieces / mm, and the discharge port 1
The number of 101 was 128.

[0039]

Example 2 A plurality of bases for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured in the same manner as in Example 1 except that the material of the upper electrode layer was changed to W. That is, 550 is obtained by continuous sputtering.
An Al layer having a thickness of 0Å and a W layer having a thickness of 2000Å are formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the compressive stress of the W layer is 5 × 10 ⁹ dyn / cm ^2. did. By simultaneously patterning the Al layer and the W layer by dry etching in the same manner as in Example 1, FIG.
A and lower electrode layer 1 made of Al as shown in FIG. 2B
110b and an upper electrode layer 1110c made of W thereon were obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0040]

Example 3 A plurality of bases for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured in the same manner as in Example 1 except that the material of the upper electrode layer was changed to Cr. That is, 55
A 00 thick Al layer, then a 2000 thick Cr layer,
The Cr layer was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the compressive stress of the Cr layer was 5 × 10 ⁹ dyn / cm ² . By simultaneously patterning the Al layer and the Cr layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al and the upper electrode layer 1 made of Cr thereon as shown in FIGS. 2A and 2B.
110c was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0041]

Example 4 A plurality of bases for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured in the same manner as in Example 1 except that the material of the upper electrode layer was changed to Ti. That is, 55
A 00 thick Al layer followed by a 2000 thick Ti layer,
The Ti layer was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the compressive stress of the Ti layer was 5 × 10 ⁹ dyn / cm ² . By simultaneously patterning the Al layer and the Ti layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al and the upper electrode layer 1 made of Ti thereon as shown in FIGS. 2A and 2B.
110c was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0042]

Example 5 A plurality of substrates for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured in the same manner as in Example 1 except that the material of the upper electrode layer was changed to Mo. That is, 55
A 00 thick Al layer followed by a 2000 thick Mo layer,
The Mo layer was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the compressive stress of the Mo layer was 5 × 10 ⁹ dyn / cm ² . By simultaneously patterning the Al layer and the Mo layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al and the upper electrode layer 1 made of Mo as shown in FIGS. 2A and 2B are formed.
110c was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0043]

Embodiment 6 An ink jet head substrate shown in FIGS. 1, 2A and 2B was manufactured in the same manner as in Embodiment 1 except that the material of the upper electrode layer was changed to an alloy composed of Ti and Mo. Were manufactured. That is, an Al layer having a thickness of 5500Å
A Ti-Mo (Mo is 5%, the balance being Ti) layer having a thickness of 00 mm is used. The compressive stress of the Ti-Mo layer is 5 × 10 ⁹ dyn / cm ^2.
It was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1. By simultaneously patterning the Al layer and the Ti-Mo layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al as shown in FIGS.
An upper electrode layer 1110c made of o was obtained. A top plate 105 made of polysulfone is applied to the plurality of ink jet head substrates 104 according to the present embodiment manufactured in this manner.
6 by pressure joining using a spring (not shown),
A and a plurality of inkjet heads 12 according to the present example as shown in FIG. 6B were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0044]

Embodiment 7 An ink jet head substrate shown in FIGS. 1, 2A and 2B was manufactured in the same manner as in Embodiment 1 except that the material of the upper electrode layer was changed to an alloy composed of Ti and Cr. Were manufactured. That is, an Al layer having a thickness of 5500Å
A Ti-Cr (Cr is 5%, the balance being Ti) layer having a thickness of 00 mm is formed on a Ti-Cr layer having a compressive stress of 5 × 10 ⁹ dyn / cm ^2.
It was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1. By simultaneously patterning the Al layer and the Ti—Cr layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al and the Ti—C layer thereon as shown in FIGS. 2A and 2B are formed.
The upper electrode layer 1110c made of r was obtained. A top plate 105 made of polysulfone is applied to the plurality of ink jet head substrates 104 according to the present embodiment manufactured in this manner.
6 by pressure joining using a spring (not shown),
A and a plurality of inkjet heads 12 according to the present example as shown in FIG. 6B were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0045]

Embodiment 8 An ink jet head substrate shown in FIGS. 1, 2A and 2B was manufactured in the same manner as in Embodiment 1 except that the material of the upper electrode layer was changed to an alloy composed of Ti and Al. Were manufactured. That is, an Al layer having a thickness of 5500Å
A Ti-Al layer (5% of Al, the balance being Ti) having a thickness of 00 ° was formed on the Ti-Al layer with a compressive stress of 5 × 10 ⁹ dyn / cm ^2.
It was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1. By simultaneously patterning the Al layer and the Ti-Al layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Al as shown in FIGS. 2A and 2B and the Ti-A on the lower electrode layer 1110b are formed.
Thus, an upper electrode layer 1110c made of l was obtained. A top plate 105 made of polysulfone is applied to the plurality of ink jet head substrates 104 according to the present embodiment manufactured in this manner.
6 by pressure joining using a spring (not shown),
A and a plurality of inkjet heads 12 according to the present example as shown in FIG. 6B were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128. In this embodiment, since the material of the upper electrode layer and the material of the lower electrode layer are common to the element of Al, the ink jet head is more excellent in strength because the adhesion between the electrode layers is larger. The substrate for use was obtained.

[0046]

Embodiment 9 A plurality of substrates for an ink jet head shown in FIGS. 1, 2A and 2B were manufactured in the same manner as in Embodiment 1 except that the material of the lower electrode layer was changed to Cu. That is, 55
A 00 thick Cu layer followed by a 2000 thick Ta layer;
The Ta layer was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the compressive stress of the Ta layer was 5 × 10 ⁹ dyn / cm ² . By simultaneously patterning the Cu layer and the Ta layer by dry etching in the same manner as in the first embodiment, the lower electrode layer 1110b made of Cu and the upper electrode layer 1 made of Ta thereon as shown in FIGS. 2A and 2B.
110c was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0047]

Embodiment 10 A substrate for an ink jet head shown in FIGS. 1, 2A and 2B was manufactured in the same manner as in Embodiment 1 except that the material of the lower electrode layer was changed to an alloy composed of Al and Si. Were manufactured. That is, an Al—Si (10% Si, the balance being Al) layer having a thickness of 5500 mm is formed by continuous sputtering, and then a Ta film having a thickness of 2000 mm is formed.
The layer was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1 so that the Ta layer had a compressive stress of 5 × 10 ⁹ dyn / cm ² . By simultaneously patterning the Al-Si layer and the Ta layer by dry etching in the same manner as in Example 1, the Al layer as shown in FIGS. 2A and 2B is formed.
A lower electrode layer 1110b made of -Si and an upper electrode layer 1110c made of Ta thereon were obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. This inkjet head 12
The arrangement density of the discharge ports 1101 is 16 pieces / mm, and the discharge port 1
The number of 101 was 128.

[0048]

Embodiment 11 A substrate for an ink jet head shown in FIGS. 1, 2A and 2B was manufactured in the same manner as in Embodiment 1 except that the material of the lower electrode layer was changed to an alloy composed of Al and Cu. Were manufactured. That is, an Al—Cu (Cu is 5%, the balance being Al) layer having a thickness of 5500Å is formed by continuous sputtering, then a Ta layer having a thickness of 2000Å is formed so that the compressive stress of the Ta layer becomes 5 × 10 ⁹ dyn / cm ² . It was formed while adjusting the argon pressure during sputtering in the same manner as in Example 1. By simultaneously patterning the Al—Cu layer and the Ta layer by dry etching in the same manner as in Example 1, the Al—Cu layer and the Ta layer are patterned as shown in FIGS. 2A and 2B.
A lower electrode layer 1110b made of Cu and an upper electrode layer 1110c made of Ta thereon were obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm,
The number of 01 was 128.

[0049]

Embodiment 12 An ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 1 except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern when dry-etching the Al layer and the Ta layer from the first embodiment and performing patterning, as shown in FIGS. 5A and 5B, the lower electrode layer made of Al which is separately separated and independent. 1110e and an upper electrode layer 1110f made of Ta thereon were obtained.
6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16
mm, and the number of discharge ports 1101 was 128.

[0050]

Embodiment 13 An ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 2 except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern of the dry etching of the Al layer and the W layer from that of the second embodiment, and performing patterning, the lower electrode layer made of individually separated and independent Al as shown in FIGS. 5A and 5B. 1110e and an upper electrode layer 1110f made of W thereon were obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / m.
m and the number of discharge ports 1101 were 128.

[0051]

Embodiment 14 The ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 3 except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, the pattern for dry-etching the Al layer and the Cr layer is changed from that of the third embodiment, and the lower electrode layer made of individually separated and independent Al is formed as shown in FIGS. 5A and 5B. 1110e and an upper electrode layer 1110f made of Cr thereon were obtained.
6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16
mm, and the number of discharge ports 1101 was 128.

[0052]

Fifteenth Embodiment An ink jet head shown in FIGS. 5A and 5B is manufactured in the same manner as in the fourth embodiment except that the patterning process by etching the lower electrode material layer and the upper electrode material layer is changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern when dry-etching the Al layer and the Ti layer from that of the fourth embodiment and performing patterning, as shown in FIGS. 5A and 5B, the lower electrode layer made of individually separated and independent Al 1110e and an upper electrode layer 1110f made of Ti thereon were obtained.
6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16
mm, and the number of discharge ports 1101 was 128.

[0053]

Embodiment 16 The ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 5, except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern when dry-etching the Al layer and the Mo layer from the fifth embodiment and performing patterning, as shown in FIGS. 5A and 5B, the lower electrode layer made of Al which is separately separated and independent. 1110e and an upper electrode layer 1110f made of Mo thereon were obtained.
6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16
mm, and the number of discharge ports 1101 was 128.

[0054]

Embodiment 17 The ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 6, except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, the pattern at the time of dry-etching the Al layer and the Ti-Mo layer is changed from that in the sixth embodiment, and thereby the lower portion made of individually separated and independent Al as shown in FIGS. 5A and 5B. Electrode layer 111
0e and an upper electrode layer 1110 made of Ti-Mo thereon
f. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0055]

Embodiment 18 The ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 7, except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, the pattern at the time of dry-etching the Al layer and the Ti—Cr layer is changed from that of the seventh embodiment, and thereby the lower portion made of individually separated and independent Al as shown in FIGS. 5A and 5B. Electrode layer 111
0e and an upper electrode layer 1110 of Ti-Cr thereon
f. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head substrates 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0056]

Embodiment 19 The ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 8 except that the patterning step by etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern at the time of dry-etching the Al layer and the Ti-Al layer from that of the eighth embodiment, and performing patterning, as shown in FIG. 5A and FIG. Electrode layer 111
0e and an upper electrode layer 1110 made of Ti-Al thereon
f. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 was 16 / mm, and the number of the ejection ports 1101 was 128.

[0057]

Embodiment 20 An ink jet head shown in FIGS. 5A and 5B is manufactured in the same manner as in Embodiment 9 except that the patterning step by etching the lower electrode material layer and the upper electrode material layer is changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern when dry etching the Cu layer and the Ta layer from that of the ninth embodiment, and performing patterning, as shown in FIG. 5A and FIG. 1110e and an upper electrode layer 1110f made of Ta thereon were obtained.
6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16
mm, and the number of discharge ports 1101 was 128.

[0058]

Embodiment 21 An ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 10 except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, the pattern at the time of dry-etching the Al-Si layer and the Ta layer is changed from that in the tenth embodiment, and the patterning is performed, so that the Al-Si layer and the Ta layer are separated from the independent Al-Si as shown in FIGS. Lower electrode layer 1110e and upper electrode layer 11 made of Ta thereon
10f was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0059]

Embodiment 22 An ink jet head shown in FIGS. 5A and 5B was manufactured in the same manner as in Embodiment 11 except that the patterning step of etching the lower electrode material layer and the upper electrode material layer was changed as follows. A plurality of substrates were manufactured. That is, by changing the pattern when dry-etching the Al-Cu layer and the Ta layer from the eleventh embodiment and performing patterning, as shown in FIG. 5A and FIG. Lower electrode layer 1110e and upper electrode layer 11 made of Ta thereon
10f was obtained. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head bases 104 according to the present embodiment using a spring (not shown). A plurality of such ink jet heads 12 according to this example were obtained. The arrangement density of the ejection ports 1101 of the inkjet head 12 is 16 pieces / mm, and the number of the ejection ports 1101 is 128
It was made into pieces.

[0060]

Comparative Example A plurality of substrates for an ink jet head shown in FIGS. 3A and 3B were manufactured in the same manner as in Example 1 except that the steps of forming the lower electrode layer and the upper electrode layer were changed as follows. Manufactured. That is, a pure Al layer having a thickness of 7500 ° was formed by sputtering, and the Al layer was patterned by dry etching using the same gas as in Example 1, to obtain an electrode layer 1110 g having a single-layer structure made of Al. 6A and 6B, the top plate 105 made of polysulfone is pressure-bonded to the plurality of inkjet head substrates 104 according to this comparative example using a spring (not shown). A plurality of such inkjet heads 12 according to this comparative example were obtained. Discharge port 1101 of this inkjet head 12
Is 16 / mm and the number of discharge ports 1101 is 12
There were eight.

[0061]

[Evaluation] The ink jet heads 12 according to the first embodiment and the comparative example were incorporated into the ink jet pen 11 and then mounted on the ink jet device 15 shown in FIG. Was done.

FIG. 4 is a graph comparing the ejection durability performance of the ink jet head according to the first embodiment and the ink jet head according to the comparative example belonging to the background art. In the graph of FIG. 4, the vertical axis represents the number of applied ejection pulses, and the horizontal axis represents the input energy amount by driving voltage (Vop) / foaming start voltage (Vth). That is, this graph is based on the input energy amount shown on the horizontal axis,
The number of ejection pulses indicated on the vertical axis indicates how many of the heating elements have been broken. As the data shown in the graph of FIG. 4, ten ink jet heads were tested for each of Example 1 and Comparative Example, and the average value thereof was used. The ejection pulse width was tested at 5 μs.

As shown in FIG. 4, it was found that the inkjet head according to Example 1 had about four times the durability as compared with the inkjet head according to the comparative example.

At the same point in time when the number of applied ejection pulses was the same, the ink jet head according to Example 1 and the ink jet head according to Comparative Example were respectively disassembled and the state of the foamed surface was observed. The ink jet head according to No. 1 had almost no protrusions on the foam surface compared to the ink jet head according to the comparative example.

Further, similar comparative tests were performed on the ink jet heads according to Examples other than Example 1, and it was confirmed that excellent results similar to Example 1 were obtained for each Example.

[0066]

According to the present invention, the lower electrode of the heater, which is most susceptible to the heat generated by the heater, has a laminated structure composed of a plurality of layers, and the layers function complementarily. The lower layer of the plurality of layers is formed of a normal electrode material having high electric conductivity. Thereby, a good electrode with little power loss can be obtained. At least the uppermost layer of the plurality of layers is formed of a high melting point metal. This layer diffuses heat to mitigate its effects, and itself functions as a layer unaffected by heat. As a result, generation of hillocks is prevented or suppressed, and formation of a convex portion on the foamed surface is also prevented or suppressed.

According to the present invention, it is possible to provide a base for forming an ink jet head having a low failure rate and a long life, and an ink jet head formed by using the base. Further, it is possible to provide a base for forming an ink jet head capable of performing good ink ejection for a long period of time, and an ink jet head formed using the base. Further, it is an object of the present invention to provide a base for forming an ink jet head in which a plurality of discharge ports are arranged at high density and capable of recording a high-definition image at high speed, and an ink jet head formed using the base. Can be. Furthermore, it is possible to provide a base for forming a miniaturized inkjet head in which the space of the substrate is saved, and an ink jet head configured using the base. Furthermore, a base for forming a low-cost inkjet head by saving space on a substrate made of a relatively expensive material such as single crystal silicon, and an inkjet head configured using the base are provided. Can be provided. In addition, it is possible to provide an ink-jet pen including an ink storage section for storing ink supplied to the above-described excellent ink-jet head, and an ink-jet device to which the ink-jet head is mounted.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a main part of an inkjet head according to an embodiment of the present invention, cut from above a heater.

2A is a schematic cross-sectional view of the main part of the inkjet head of FIG. 1 taken along line AA ′, and FIG. 2B is a main part of the inkjet head of FIG. 1 taken along line BB ′. FIG.

3A is a schematic cross-sectional view of a main part of an ink-jet head according to the background art viewed from the same direction as FIG. 2A, and FIG. 3B is a schematic cross-sectional view viewed from the same direction as FIG. 2B.

FIG. 4 is a graph comparing the ejection durability performance of the inkjet head according to Example 1 and the inkjet head belonging to the background art.

5A is a schematic cross-sectional view of a main part of an inkjet head according to another embodiment of the present invention, as viewed from the same direction as FIG. 2A, and FIG. 5B is a schematic cross-sectional view as viewed from the same direction as FIG. 2B. FIG.

FIG. 6A is a schematic perspective view showing an inkjet head according to one embodiment of the present invention. FIG. 6B is FIG.
FIG. 4 is a schematic cross-sectional view of the inkjet head shown in FIG.

FIG. 7 is a schematic perspective view showing a main part of an ink jet device equipped with a cartridge type ink pen incorporating the ink jet head shown in FIGS. 6A and 6B.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Ink-jet pen 12 Ink-jet head 15 Ink-jet device 16 Carriage 103 Substrate 104 Ink-jet head base 105 Top plate 1101 Discharge port 1102 Heating part 1103 Resistor layer 1104 Orifice plate 1111 Lower insulating layer 1112 Upper insulating layer 1113 Lower protective film 1114 Upper protective film 1116 Foaming surface 1110a Individual electrode layer 1110b Lower electrode layer 1110c Upper electrode layer

──────────────────────────────────────────────────続 き Continued from the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/05 B41J 2/16

Claims (32)

(57) [Claims] 1. A heat generating device including a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers is used for discharging ink. An electrothermal transducer serving as a heat-generating portion that generates energy, and a substrate on which the electrothermal transducer is provided, wherein the substrate for an inkjet head includes one of the pair of electrode layers. The electrode layer located below the heat generating portion has a laminated structure including a plurality of layers, passing under the heat generating portion, and at least the layer closest to the heat generating portion among the plurality of layers is A base for an ink jet head, comprising a metal having a melting point of not less than 1500 degrees Celsius at 1 atm. 2. The substrate for an ink jet head according to claim 1, wherein the metal has a melting point of 2500 ° C. or more at 1 atm. 3. The metal is Ta, W, Cr, Ti, M
2. The substrate for an ink jet head according to claim 1, wherein the substrate is an o or an alloy comprising two or more metal elements selected from these metal elements. 4. The substrate for an ink jet head according to claim 1, wherein the metal is an alloy containing a metal element selected from Ta, W, Cr, Ti, and Mo. 5. The substrate for an ink jet head according to claim 1, wherein the layer closest to the heat generating portion has a compressive stress. 6. The substrate for an ink jet head according to claim 1, wherein the layer farther from the heat generating portion is made of a metal having a melting point of less than 1500 degrees Celsius at 1 atm. 7. The layer farther from the heat-generating portion is made of Al, C
The substrate for an inkjet head according to claim 1, wherein the substrate is u, an Al-Si alloy, or an Al-Cu alloy. 8. The substrate for an ink jet head according to claim 1, wherein an insulating layer is provided between the resistor layer and a layer farther from the heat generating portion. 9. The substrate for an ink jet head according to claim 8, wherein said insulating layer is made of silicon oxide or silicon nitride. 10. The substrate for an ink jet head according to claim 1, wherein a plurality of the heat generating portions are provided. 11. The substrate for an ink jet head according to claim 1, wherein a layer closest to the heat generating portion and a layer far from the heat generating portion are formed in the same pattern. 12. The substrate for an ink jet head according to claim 10, wherein said plurality of layers are common electrodes provided in common to said plurality of heat generating portions. 13. The substrate for an ink jet head according to claim 10, wherein the plurality of layers are provided separately and independently corresponding to the plurality of heat generating portions. 14. The ink jet head according to claim 1, wherein at least the surface of the substrate has an insulating property. 15. The substrate for an ink jet head according to claim 1, wherein a protective layer is provided on the electrothermal transducer. 16. A heat source including a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers is used for discharging ink. An ink-jet head base including an electrothermal converter serving as a heat generating portion for generating energy; and a substrate on which the electrothermal converter is provided, and an ink path corresponding to the heat generating portion. An ink jet head provided with an ejection port for ejecting ink in communication with the ink path, wherein one of the pair of electrode layers passes under the heat generating portion, and The electrode layer located below the portion has a laminated structure composed of a plurality of layers, and at least the layer closest to the heating portion among the plurality of layers has a melting point of 1500 degrees Celsius under 1 atm. Characterized by being made of a metal as described above Ink jet head. 17. The ink jet head according to claim 16, wherein the melting point of the metal at 1 atm is 2500 degrees Celsius or more. 18. The metal may be Ta, W, Cr, Ti, M
17. The inkjet head according to claim 16, wherein the inkjet head is o or an alloy composed of two or more metal elements selected from these metal elements. 19. The ink jet head according to claim 16, wherein the metal is an alloy containing a metal element selected from Ta, W, Cr, Ti, and Mo. 20. The ink jet head according to claim 16, wherein a layer closest to the heat generating portion has a compressive stress. 21. The ink jet head according to claim 16, wherein the layer farther from the heat generating portion is made of a metal having a melting point of less than 1500 degrees Celsius at 1 atm. 22. A layer farther from the heating section is made of Al,
The inkjet head according to claim 16, wherein the inkjet head is made of Cu, an Al-Si alloy, or an Al-Cu alloy. 23. The ink jet head according to claim 16, wherein an insulating layer is provided between the resistor layer and a layer far from the heat generating portion. 24. The ink jet head according to claim 23, wherein said insulating layer is made of silicon oxide or silicon nitride. 25. The ink jet head according to claim 16, wherein a plurality of the ejection ports are provided, and a plurality of the heat generating portions are provided corresponding to the plurality of ejection ports, respectively. 26. The ink jet head according to claim 16, wherein a layer closest to the heat generating portion and a layer far from the heat generating portion are formed in the same pattern. 27. The ink jet head according to claim 25, wherein the plurality of layers are common electrodes provided in common to the plurality of heat generating portions. 28. The ink jet head according to claim 25, wherein the plurality of layers are provided separately and independently corresponding to the plurality of heat generating portions. 29. The ink jet head according to claim 16, wherein the electrothermal transducer is provided on a substrate having at least a surface having an insulating property. 30. The ink jet head according to claim 16, wherein a protective layer is provided on the electrothermal transducer. 31. A heat source including a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers is used for discharging ink. An ink-jet head base including an electrothermal converter serving as a heat generating portion for generating energy; and a substrate on which the electrothermal converter is provided, and an ink path corresponding to the heat generating portion. An ink-jet pen having an ink-jet head provided with a discharge port for discharging ink in communication with the ink path, and an ink storage section for storing ink supplied to the ink path. An electrode layer of one of the pair of electrode layers passes below the heat generating portion, and an electrode layer located below the heat generating portion has a laminated structure including a plurality of layers. At least to the heating part Close side layer ink-jet pen, wherein the melting point of 1 atm is made of a metal is more than 1500 degrees Celsius. 32. A heating device including a resistor layer and a pair of electrode layers connected to the resistor layer, wherein the resistor layer located between the pair of electrode layers is used for discharging ink. An ink-jet head base including an electrothermal converter serving as a heat generating portion for generating energy; and a substrate on which the electrothermal converter is provided, and an ink path corresponding to the heat generating portion. And an ink jet head provided with a discharge port for discharging ink in communication with the ink path; mounting means for mounting the ink jet head;
An ink-jet apparatus having a laminated structure in which one electrode layer of the pair of electrode layers passes under the heat-generating portion, and an electrode layer located below the heat-generating portion has a plurality of layers. An ink jet apparatus wherein at least a layer of the plurality of layers closest to the heat generating portion is made of a metal having a melting point of 1500 ° C. or more at 1 atm.