JP3438526B2 - Ink jet head and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms an electrothermal converter in each ink flow path, and causes heat generated by the electrothermal converter to act on the ink to remove ink from the orifice at the tip of the ink flow path. The present invention relates to an inkjet recording-type inkjet head that performs recording by ejecting droplets and a method for manufacturing the inkjet head.

[0002]

2. Description of the Related Art The ink jet recording system is a system for recording by ejecting ink as minute liquid droplets and adhering them to a recording medium. This recording method has a feature that a high-definition image can be recorded at high speed. In particular, the thermal ink jet method, which utilizes an electrothermal converter as a means for ejecting ink and utilizes the bubbling phenomenon of the ink generated by applying thermal energy to the ink, is excellent in device performance such as downsizing of the head and the device. ing. Further, there is an increasing demand for high definition and high speed recording of images.

FIG. 6 is a plan view showing an example of a conventional ink jet head, and FIG. 7 is a sectional view of the same. In the figure,
1 is a substrate, 2 is a silicon oxide film, 4 is an insulating layer, 5 is a heating resistor layer, 6 is a metal wiring layer, 7 is an inorganic protective layer, 8 is a tantalum layer, 9 is an ink channel, 10 is a top plate, Reference numeral 11 is a flow path partition wall, 31 is an orifice, and 32 is an electrothermal converter. Note that FIG. 7 shows a cross section taken along the line CC ′ in FIG. 6.

As shown in FIG. 6, the ink jet head is provided with a plurality of orifices 31 serving as ink ejection ports, and a plurality of ink flow paths 9 communicating with the orifices 31. The ink flow path 9 includes a flow path partition wall 11 and FIG.
As shown in FIG. 2, the substrate 1 and the top plate 10 on which each layer is formed are configured. Each ink flow path 9 is provided with an electrothermal converter 32 that generates thermal energy used to eject ink. Each electrothermal converter 32 is
It is mainly composed of a heating resistor layer 5 and a metal wiring layer 6 for supplying electric power thereto.

Further, as shown in FIG. 7, a silicon oxide film 2 and an insulating film 4 are formed on a substrate 1 made of silicon or the like, and a pattern as shown in FIG. 6 is formed on these layers. The heating resistor layer 5 is formed, and the metal wiring layer 6 having the pattern as shown in FIG. 6 is also formed on the heating resistor layer 5. The portion of the heating resistor layer 5 excluding the metal wiring layer 6 constitutes the electrothermal converter 32. Furthermore, an inorganic protective layer 7 and a tantalum layer 8 are formed to protect these layers.

In the configuration shown in FIG. 6, the electrothermal converter 32.
And the metal wiring for supplying electric power to the electrothermal converter 32 are formed adjacent to each other in the same plane, the electrothermal converter 32
The width of the heat generating resistor layer 5 and the width of the metal wiring layer 6 constituting the above are limited. This is a problem which becomes apparent as a cause of insufficient volume of bubbles for ejecting ink and increase of current density in the metal wiring in order to increase the resolution of the inkjet head.

As a means for solving this problem, there has been proposed a structure in which at least one side of the metal wiring for supplying electric power to the electrothermal converter 32 is provided in a layer different from the heating resistor layer. For example, in Japanese Utility Model Publication No. 6-28272, a conductor layer serving as a common electrode is connected to a metal layer formed below the undercoat layer through a contact hole formed in the heating resistor layer and the undercoat layer. Disclosed configurations are disclosed. The conductor layer serving as the common electrode is originally provided in order to satisfactorily radiate the heat generated in the electrothermal converter to the substrate, and a metal such as tantalum, molybdenum, or tungsten having good thermal conductivity is used. ing.

However, when a metal such as tantalum, molybdenum, or tungsten is used for the metal layer, heat is generated from the metal layer due to the relatively large volume resistivity of these metals. As described above, the metal layer is provided for heat dissipation, but if the metal layer itself generates heat, the thermal conductivity also deteriorates. Therefore, when a plurality of electrothermal converters are heated to continuously eject ink, there is a problem that the temperature of the inkjet head itself rises. This increase in temperature also affects the surface temperature of the electrothermal converter that acts on the growth of bubbles, hinders uniform foaming, and deteriorates image quality. Further, since energy is consumed in the metal layer, the ratio of energy contributing to ink ejection to input energy is reduced, resulting in poor energy efficiency. Further, since the electrothermal converter adjacent to the electrothermal converter that has generated heat to eject ink is affected by the heat generated during ink ejection, unnecessary ink ejection or unstable ejection is likely to occur. . These problems become more serious problems as the number of electrothermal converters simultaneously driven increases due to speeding up and the distance between electrothermal converters decreases due to higher image quality.

For example, in the ink jet head described in Japanese Patent Laid-Open No. 7-314690, one of the pair of electrode layers connected to the resistor layer has one electrode layer below the heat generating portion, as in the above-mentioned document. And a structure in which the upper and lower electrode layers are connected by a through hole for contact. However, in this document, the upper electrode layer connected to the heat generating portion is made of a high melting point metal having a melting point of 1500 degrees or more under 1 atmosphere, and the lower electrode layer passing under the heat generating portion is made of Al, Cu or Al. By using -Cu or an Al-Si alloy, an electrode having high reliability and low resistance is formed, and the above-mentioned problem is solved. This document also discloses an example in which the lower electrode is arranged as a common electrode and an example in which the lower electrode is formed as an individual electrode.

However, in any of the documents, the upper electrode and the lower electrode are connected via a through hole opened in an insulating layer that insulates the upper electrode and the lower electrode. FIG. 8 is a sectional view showing another example of a conventional inkjet head. In the figure, the same parts as those in FIGS. 6 and 7 are designated by the same reference numerals, and the description thereof will be omitted. Reference numeral 3 is a lower metal wiring layer, and 33 is a through hole portion. In this example, the lower metal wiring layer 3 is formed between the silicon oxide film 2 and the insulating layer 4, and the through hole portion 3 is formed in the insulating layer 4.
3 is provided to electrically connect the lower metal wiring layer 3 and the metal wiring layer 6.

In general, the inorganic protective layer 7, the tantalum layer 8 and the like for protecting the metal wiring layer 6 of the through hole portion 33 are formed by the plasma CVD method or the sputtering method. Figure 8
When the through-hole portion 33 is formed as shown in Fig. 8, the inorganic protective layer 7 and the tantalum layer 8 for protecting the electrodes formed thereon tend to have non-uniform thickness, and as shown in Fig. 8. In addition, unevenness is generated on the through hole portion 33. If such unevenness is generated in the ink flow path 9, it becomes a factor that makes the flow of ink unstable and causes the flight direction of the ink droplet to become unstable. In addition, as shown by the thick arrow in FIG. 8, the inorganic protective layer 7 is formed at the corners of the protrusions and depressions.
Concentration of the stress inherent in the protective layer such as the or tantalum layer 8 occurs. In such a situation, if the ink ejection operation is continued, the ink is likely to be destroyed by the physical pressure caused by the bubbles generated in the ink, and the ink enters from the destroyed location to cause corrosion of the metal wiring layer 6. Such,
This has been a factor in reducing the life of the inkjet head.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a long-life ink jet head capable of performing good ink ejection for a long period of time, and a method of manufacturing the same. It is intended.

[0013]

According to the present invention, in an ink jet head, at least a lower metal wiring layer, an insulating layer, a heating resistor layer and an upper metal wiring layer are laminated in this order on a substrate, The upper metal wiring layer is removed in the portion of the resistor area that becomes the converter, and the insulating layer is removed from the vicinity of the orifice side end of the resistor area in the orifice side.
Thus, the heating resistor layer and the lower metal wiring layer are electrically connected in the vicinity of the orifice-side end of the resistor region. In such a structure, in the structure in which the lower metal wiring layer is provided under the electrothermal converter, the heating resistor layer and the lower metal wiring layer can be connected without passing through the through hole, so that the ink flow There is minimal unevenness in the path and it does not disturb the ink flow. Further, even if a protective layer or the like is laminated on these, the concentration of the stress inherent in the protective layer does not occur, so that the protective layer is not destroyed and the electrode is not corroded due to the invasion of the ink. A long-life inkjet head capable of ejecting for a long period of time can be obtained.

[0014]

1 is a plan view of a substrate showing a first embodiment of an ink jet head of the present invention, FIG.
Is a sectional view taken along the line AA ′ and FIG. 3 is a sectional view taken along the line BB ′. In the figure, parts similar to those in FIGS. 6 to 8 are designated by the same reference numerals, and description thereof will be omitted. 21 is an insulating layer removal area,
Reference numeral 22 is an electric connection region, and 23 is an electrothermal converter. In FIG. 1, the top plate 10 and the flow path partition walls 11 are removed, and the inorganic protective layer 7, the tantalum layer 8 and other protective layers are also removed.

A silicon oxide film 2 is formed on a substrate 1 made of silicon or the like, and a lower metal wiring layer 3 which is an individual electrode is patterned and formed thereon corresponding to each ink flow path 9. The side metal wiring layer 3 extends from the side opposite to the orifice of each ink flow path 9 toward the orifice, and is equivalent to the electrical connection region 22 from the end of the region that becomes the electrothermal converter 23 on the orifice side. It is formed up to the orifice side.

Further, an insulating layer 4 is formed on it. The insulating layer 4 is, as shown in FIG.
A portion of the insulating layer removal region 21, which is a region on the orifice side, is removed from the end of the region on the orifice side on the orifice side.
The lower metal wiring layer 3 under the insulating layer 4 is exposed in the insulating layer removal region 21.

A heating resistor layer 5 and a metal wiring layer 6 are formed on the insulating layer 4. This metal wiring layer 6 is the upper metal wiring layer. The heating resistor layer 5 is formed with at least an individual portion corresponding to each ink flow path 9, and this individual portion includes a region of the electrothermal converter 23 and extends forward and backward with respect to the ink flow direction. ing. The orifice side of the heating resistor layer 5 is formed so as to extend to the insulating layer removal region 21 and is electrically connected to the lower metal wiring layer 3 at the electrical connection portion 22. The insulating layer 4 insulates the lower metal wiring layer 3 from the portion other than the electrical connection portion 22. In this example, the pattern on the side opposite to the orifice of the electrothermal converter 23 is formed in the same pattern as the metal wiring layer 6, but at least the region of the electrothermal converter 23 and the lower metal wiring layer 3 are formed. It suffices if there is a portion that is electrically connected to the electrical connection portion 22 and the metal wiring layer 6 that are connected. As the heating resistor layer 5, metal nitride, metal boride, metal oxide, metal carbide, or the like can be used.

In this example, the metal wiring layer 6 forms a common electrode, and as shown in FIG. 1, the end of the region of the electrothermal converter 23 on the heating resistor layer 5 opposite to the orifice. Are formed, and each is formed as an integral pattern that is electrically connected. In the heating resistor layer 5, the electrothermal converter 23 extends from the orifice-side end of the metal wiring layer 6 to the electrical connection portion 22.

Furthermore, in this example, an inorganic protective layer 7 and a tantalum layer 8 are formed thereon as protective layers. The inorganic protective layer 7 prevents corrosion due to the metal wiring layer 6 coming into contact with ink. Further, the tantalum layer 8 protects the inside from the physical pressure generated when the bubbles grown in the ink flow path 9 disappear. The tantalum layer 8 is provided at least on the electrothermal converter 23. In this example, it is provided on the entire surface. In addition, the inorganic protective layer 7 may be configured, for example, by removing the upper portion of the electrothermal converter 23 and forming a recess to improve the efficiency of heat transfer to the ink and guide the growth of bubbles. The protective layer is not limited to this example,
Various layer structures can be adopted.

On the other hand, in this example, the flow path partition wall 1 is provided on the top plate 10.
A groove is formed which becomes the ink flow path 9 and is partitioned by 1. The top plate 10 is attached to the substrate 1 formed as described above, and as shown in FIG.
Is formed. In this example, the flow path partition 11 is formed integrally with the top plate 10. However, for example, the flow path partition 11 is patterned and formed on the substrate 1 by using a resin or the like, and the flat top plate 10 is mounted. It may be configured to.

Next, an example of the manufacturing method of the first embodiment of the ink jet head of the present invention will be described using a specific example. A silicon oxide film 2 is formed on a substrate 1 made of silicon. The lower metal wiring layer 3 is formed by depositing Al or an Al alloy such as Al-Si or Al-Cu on the film by sputtering and patterning it into a desired shape by dry etching or wet etching. An insulating layer 4 is formed by depositing a silicon oxide film thereon by a sputtering method or a CVD method. Next, the silicon oxide film in the insulating layer removal region 11 is etched by dry etching. A tantalum nitride or hafnium boride film is deposited thereon by a sputtering method and is patterned into a desired shape by dry etching or wet etching to form the heating resistor layer 5. Similarly, Al or an Al alloy such as Al-Si or Al-Cu is deposited by a sputtering method and is patterned into a desired shape by dry etching or wet etching to obtain the metal wiring layer 6. Further, a silicon oxide film, a silicon nitride film, or a silicon oxynitride film is deposited thereon as an inorganic protective layer 7 by a sputtering method or a CVD method, and a tantalum layer 8 is further deposited by a sputtering method, thereby forming an inkjet head. The substrate 1 for can be manufactured.

On the other hand, the top plate 10 has a groove to be the ink flow path 9 formed on a substrate such as silicon by dicing or anisotropic etching. Alternatively, a resin is molded and a groove is formed at the time of molding, or a groove is formed after molding by, for example, laser processing. Then, the inkjet head is obtained by aligning with the substrate 1 and adhering it with, for example, an adhesive, or pressing and joining it with an elastic member or the like.

When recording is performed by the ink jet head manufactured in this way, a signal corresponding to image recording information is applied to the electrothermal converter 23 via the lower metal wiring layer 3 which is an individual electrode. An electric current flows through the heating resistor layer 5 of the electrothermal converter 23 to generate heat, and the generated heat acts on the ink existing in the ink flow path 9,
Film boiling occurs in the ink. Ink is ejected from the orifice according to the growth of bubbles due to the boiling, and the ink is ejected as an ink droplet and adheres to the recording medium to perform recording. In the portion where the heating resistor layer 5 and the metal wiring layer 6 overlap, the current passes through the metal wiring layer 6, so that the heating resistor layer 5 does not generate heat.

According to the ink jet head shown in the first embodiment, as can be seen from FIG. 2, the heating resistor layer 5 and the lower metal wiring layer 3 are connected without using a through hole. Since the coverage of the protective layer covering the electrical connection portion 22 is made uniform, and a structure having less unevenness in the ink flow path 9 can be realized, the physical force of bubbles generated in the ink flow path 9 and In addition, it is less susceptible to stress concentration inherent in the protective layer, cracking of the protective layer is reduced, and a long-life inkjet head can be obtained. Further, since there are few irregularities, the ink flow in the ink flow path 9 becomes uniform, and the ink ejection direction can be stabilized. Further, in this structure, since the flow passage cross-sectional area expands toward the orifice, the flow passage resistance from the bubble generation position to the orifice is small and the energy efficiency is improved.

Since the lower metal wiring layer 3 is formed as an individual electrode, the heat reaching the lower metal wiring layer 3 is
It is not transmitted through the lower metal wiring layer 3 to the adjacent electrothermal converter 23. Therefore, the thermal characteristics of the adjacent electrothermal converters 23 can be maintained substantially uniform, and unnecessary ink ejection from the adjacent orifices can be reduced. Furthermore, since the lower metal wiring layer 3 is an individual electrode, it is possible to fabricate a drive circuit or the like for operating the electrothermal converter 23 on the same silicon substrate 1. These drive circuits are
It can be configured by an OS or the like.

FIG. 4 is a sectional view showing a second embodiment of the ink jet head of the present invention. In the figure, the same parts as those in FIGS. 1 to 3 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 24 is an inclined region. In this embodiment, when the orifice side of the insulating layer 4 is removed, the end face is inclined and the inclined region 24 is provided. Due to this inclined region 24, the ink flow path 9 is formed by the end portion of the insulating layer 4.
The convex portion projecting inward becomes a slope as shown in FIG.
Therefore, the unevenness in the ink flow path 9 is further reduced as compared with the above-described first embodiment, and it is possible to further mitigate the influence of physical pressure caused by bubbles and corrosion caused by ink caused by cracking of the protective layer. This makes it possible to perform good ink ejection for a long period of time.

As a method of manufacturing such an ink jet head, after the insulating layer 4 is laminated in the above-described first embodiment, the insulating layer removal area 21 is exposed in order to expose the lower metal wiring layer 3. When the oxide film is removed, inclined etching is performed by wet etching or dry etching to form a tapered shape in the inclined region 24. After that, the heating resistor layer 5, the metal wiring layer 6, the inorganic protective layer 7, the tantalum layer 8 and the like are laminated in the same manner as in the first embodiment. Inclined area 24
In the above, each layer that is sequentially laminated also has a tapered shape, and appears as a slope in the ink flow path 9 as shown in FIG. Therefore, the unevenness in the ink flow path 9 is reduced, and the concentration of physical pressure due to bubbles can be further alleviated. The electrothermal converter 23 is a region including the inclined region 24, which is sandwiched between the electrical connection region 22 and the metal wiring layer 6.

FIG. 5 is a sectional view showing the third embodiment of the ink jet head of the present invention. In the figure, parts similar to those in FIGS. 1 to 4 are designated by the same reference numerals, and description thereof will be omitted. Reference numeral 12 is a lower heating resistor layer. In addition to the above-described second embodiment, the third embodiment shows an example in which the lower heating resistor layer 12 is provided between the lower metal wiring layer 3 and the insulating layer 4. The lower heating resistor layer 12 is made of the same material as that of the heating resistor layer 5, and is formed in a pattern substantially similar to that of the lower metal wiring layer 3.

According to such a configuration, the electrical connection area 2
Since the layer contributing to the connection with the heating resistor layer 5 in 2 is the lower heating resistor layer 12 made of the same material as the heating resistor layer 5, highly reliable electrical contact can be obtained. Further, since the lower heating resistor layer 12 is thermally strong, it is possible to cover the lower metallic wiring layer 3 therebelow and protect the lower metallic wiring layer 3 from thermal shock. Therefore, it is possible to obtain an ink jet head having a longer life.

As a method for manufacturing such an ink jet head, after forming a silicon oxide film 2 on a substrate 1 made of silicon or the like, the lower side is made of Al or an Al alloy such as Al--Si or Al--Cu by a sputtering method. The metal wiring layer 3 is deposited, and the lower heating resistor layer 12 is deposited using the same material as the heating resistor layer 5, and is patterned into a desired shape by dry etching or wet etching. At this time, the film thickness of the lower heating resistor layer 12 deposited is such that the film thickness ratio of the lower heating resistor layer 12 to the film thickness of the lower metal wiring layer 3 is 40% or less, preferably 20% or less. It is good to form it. Subsequent layers may be formed in the same manner as in the second embodiment described above.

In the example shown in FIG. 5, the lower heating resistor layer 12 is added to the structure shown in the second embodiment.
Although the example in which the lower heating resistor layer 12 is provided is shown, the lower heating resistor layer 12 may be provided in the configuration shown in the first embodiment.

[0032]

As is apparent from the above description, according to the present invention, the metal wiring for supplying electric power to the electrothermal converter is provided with the upper metal wiring layer and the lower metal formed on the lower layer of the electrothermal converter. The unevenness can be reduced by connecting the heating resistor layer and the lower metal wiring layer in the region where the insulating layer is removed without passing through the through hole by using the wiring layer. It is possible to make the coverage of the protective layer that covers the electrical connection portion with the side metal wiring layer uniform and reduce the concentration of internal stress. In addition, since the unevenness in the ink flow path is reduced, the ink flow in the ink flow path is uniform, the ink ejection direction is stable, and the number of locations where physical pressure from bubbles is concentrated is reduced. As a result, it is possible to obtain a long-life inkjet head by preventing cracks in the protective layer, corrosion of electrodes caused by ink invading through the cracks in the protective layer, and suppressing a decrease in ejection life. By making the end portion of the protective layer on the orifice side inclined, it is possible to further reduce irregularities and enhance these effects. Further, by providing the heating resistor layer also on the lower metal wiring layer, it is possible to electrically connect the upper heating resistor layer and the lower metal wiring layer with the same kind of material. The connection reliability can be improved and the lower metal wiring layer can be protected from thermal shock.

Further, since the lower metal wiring layer is formed as an individual electrode individually arranged for each electrothermal converter, heat generated by the electrothermal converter is adjacent to the electrothermal converter via the lower metal wiring. Since it does not act on the converter, a decrease in the efficiency of ejection energy with respect to the applied electrical energy is avoided, and unnecessary ink ejection or unstable ink ejection is caused by the heat generated in the adjacent electrothermal converter. It is possible to continue stable ink ejection. Furthermore, since the lower metal wiring layer is an individual electrode, it becomes possible to fabricate a drive circuit and the like for operating the electrothermal converter on the same silicon substrate, which results in higher resolution and higher density of the inkjet head. At the same time, there is an effect that the miniaturization of the entire device can be achieved.

[Brief description of drawings]

FIG. 1 is a plan view of a substrate showing a first embodiment of an inkjet head of the present invention.

FIG. 2 is a sectional view taken along the line AA ′ showing the first embodiment of the inkjet head of the present invention.

FIG. 3 is a BB ′ cross-sectional view showing the first embodiment of the inkjet head of the present invention.

FIG. 4 is a cross-sectional view showing a second embodiment of an inkjet head of the present invention.

FIG. 5 is a sectional view showing a third embodiment of an inkjet head of the present invention.

FIG. 6 is a plan view showing an example of a conventional inkjet head.

FIG. 7 is a cross-sectional view showing an example of a conventional inkjet head.

FIG. 8 is a cross-sectional view showing another example of a conventional inkjet head.

[Explanation of symbols]

1 ... Substrate, 2 ... Silicon oxide film, 3 ... Lower metal wiring layer,
4 ... Insulating layer, 5 ... Heating resistor layer, 6 ... Metal wiring layer, 7 ...
Inorganic protective layer, 8 ... Tantalum layer, 9 ... Ink flow path, 10 ...
Top plate, 11 ... Flow path partition wall, 12 ... Lower heating resistor layer, 21
... Insulating layer removal area, 22 ... Electrical connection area, 23 ... Electrothermal converter, 24 ... Inclined area.

Front page continued (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/05 B41J 2/16 B41J 2/345

Claims (7)

(57) [Claims] 1. An electrothermal converter is formed in an ink flow path, and heat generated by the electrothermal converter is applied to ink to eject ink droplets from an orifice at the tip of the ink flow path. In an inkjet recording type inkjet head for recording, at least a lower metal wiring layer, an insulating layer, a heating resistor layer, and an upper metal wiring layer are laminated in this order on a substrate. A resistor region where the upper metal wiring layer does not exist is provided on the upper portion, and the insulating layer is removed from the vicinity of the orifice side end of the resistor region to the orifice side end of the substrate. The end portion on the orifice side has an inclined shape, and the heating resistor layer and the lower metal wiring layer are electrically connected to each other in the vicinity of the end portion on the orifice side of the resistor region. The ink jet head is characterized in that the electrothermal converter is formed by the resistor region from a continuous portion to an end of the metal wiring layer of the upper metal wiring layer. 2. An electrothermal converter is formed in the ink flow path, and the heat generated by the electrothermal converter is applied to the ink to eject ink droplets from the orifice at the tip of the ink flow path. In an inkjet head of an inkjet recording system for recording, at least a lower metal wiring layer, an insulating layer, a heating resistor layer, and an upper metal wiring layer are laminated in this order on a substrate, and the lower metal wiring is A heating resistor layer is also formed between the insulating layer and the insulating layer, a resistor region where the upper metal wiring layer does not exist is provided on the heating resistor layer, and the orifice of the resistor region is provided. The insulating layer is removed from the vicinity of the side end portion to the orifice side end of the substrate, and the heating resistor layer and the lower metal wiring layer are electrically charged near the orifice side end portion of the resistor region. An ink jet head, which is electrically connected, and wherein the electrothermal converter is formed by the resistor region from the connecting portion to an end of the metal wiring layer of the upper metal wiring layer. 3. The ink jet head according to claim 2, wherein an end portion of the insulating layer on the orifice side has an inclined shape. 4. The lower metal wiring layer is an individual electrode corresponding to the electrothermal converter, and the upper metal wiring layer is a common electrode connected to the adjacent upper metal wiring layer. The inkjet head according to any one of claims 1 to 3. 5. An electrothermal converter is formed in the ink flow path, and the heat generated by the electrothermal converter is applied to the ink to eject ink droplets from the orifice at the tip of the ink flow path. In a method of manufacturing an inkjet head of an inkjet recording method for recording, a lower metal wiring layer corresponding to the ink flow path is formed on a substrate, and an insulating layer is formed on the lower metal wiring layer to form a position where the electrothermal converter is formed. Of the lower metal wiring layer from the end on the orifice side to the end on the orifice side of the substrate, and the end on the orifice side of the insulating layer is inclined, and at least the electric heat At the position where the converter is formed, it is formed so as to correspond to the ink flow path, and its tip extends beyond the end of the insulating layer and is electrically connected to the lower metal wiring layer. A heat resistor layer is formed, an upper metal wiring layer is formed on a region of the heat generating resistor layer other than a position where the electrothermal converter is formed, and the heat generating resistor layer is connected to the lower metal wiring layer. A method for manufacturing an inkjet head, wherein a region from a portion to an end of the metal wiring layer is used as the electrothermal converter. 6. An electrothermal converter is formed in the ink flow path, and the heat generated by the electrothermal converter is applied to the ink to eject ink droplets from the orifice at the tip of the ink flow path. In a method for producing an inkjet head of an inkjet recording method for recording, a lower metal wiring layer corresponding to the ink flow path is formed on a substrate, a heating resistor layer is formed thereon, and an insulating layer is formed thereon. After the formation of the electrothermal converter, the end of the lower metal wiring layer on the orifice side to the end of the substrate on the orifice side is removed, and at least the electrothermal converter forming position is formed thereon. Then, a heating resistor layer is formed so as to correspond to the ink flow path, and its tip extends beyond the end of the insulating layer and is electrically connected to the lower metal wiring layer, The fever resistance An upper metal wiring layer is formed in a region on the antibody layer excluding the formation position of the electrothermal converter, and from the connection portion of the heating resistor layer with the lower metal wiring layer to the end portion of the metal wiring layer. A method for manufacturing an inkjet head, characterized in that a region is used as the electrothermal converter. 7. The method of manufacturing an ink jet head according to claim 6, wherein an end portion of the insulating layer on the orifice side has an inclined shape.