JP2002011888A - Method of making base body for ink jet recording head, method of making ink jet recording head, ink jet recording head, and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a uniform protection layer at a step section of a heating element. SOLUTION: Firstly, a heat accumulating layer 2, a heating resistor layer 3 and an electrode layer 4a are formed on a substrate 1. Then, patterning of a resist 11 is applied on the electrode layer. A first stage of etching of the electrode layer 4a and the heating resistor layer 3 is executed by a wet etching method in such a manner that the electrode layer 4a having the thickness t1 is etched to leave the thickness t2 thereof. The pattern of the resist 11 is recessed by a distance S by a dry etching method. After the dry etching is completed, a dipping treatment is executed by a polymer removing liquid to remove a polymer. A second stage of etching of the electrode layer 4a is executed by a wet etching method to expose the heating resistor layer 3. As the electrode layer 4a is etched by two stages, a tapered portion 10 is formed at the step section 12. After the resist 11 is peeled, the upper protection layer 5 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a substrate for an ink jet recording head, a method for manufacturing an ink jet recording head, an ink jet recording head, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art Among various recording methods known at present, this is a non-impact recording method in which almost no noise is generated at the time of recording, high-speed recording is possible, and special fixing to plain paper is performed. The so-called ink jet recording method (ink jet recording method), which can perform recording without requiring processing, is an extremely useful recording method. Regarding the ink jet recording method, various methods have been proposed so far, some of which have been commercialized with improvements, and some of which are still being put to practical use.

In the ink-jet recording method, recording is performed by causing droplets of a recording liquid, called ink, to fly by various action principles and attaching the droplets to a recording material such as paper.

[0004] The present applicant has already proposed a new method relating to the ink jet recording method. This new method is disclosed, for example, in Japanese Patent Application Laid-Open No. 52-1187.
No. 98, the basic principle of which is as outlined below. In other words, this ink jet recording method gives a thermal pulse as an information signal to the recording liquid introduced into the working chamber capable of containing the recording liquid, whereby the recording liquid generates a vapor bubble and self-shrinks. In this method, a recording liquid is discharged from a liquid discharge port communicating with a working chamber in accordance with an acting force generated in the process, and is ejected as small droplets, and the droplet is attached to a recording material to perform recording.

[0005] By the way, since this method has a high-density multi-array configuration, it is easy to adapt to high-speed recording and color recording, and the configuration of the apparatus is simpler than in the past, so that the recording head described below is generally compact. To be more suitable for mass production, and to make full use of the advantages of IC technology and micro-machining technology, which have made remarkable advances in technology in the field of semiconductors, etc. It has the advantage of being a flexible method.

A characteristic recording head of an ink jet recording apparatus used in the above-mentioned ink jet recording method is provided with a thermal energy generating means for discharging a recording liquid from a liquid discharge port to form flying droplets.

[0007] The thermal energy generating means may be in direct contact with the recording liquid in order to efficiently apply the generated thermal energy to the recording liquid and to increase the ON-OFF response speed of the thermal action on the recording liquid. It is desirable to be provided in.

However, since the above-mentioned thermal energy generating means is basically composed of a heat generating resistance layer which generates heat when energized, and a pair of electrodes for energizing this heat generating resistance layer, If the heating resistance layer is in direct contact with the recording liquid, depending on the electric resistance value of the recording liquid, electricity flows through the recording liquid, or the recording liquid itself is electrolyzed by the flow of electricity through the recording liquid, Alternatively, when the heating resistor layer is energized, the heating resistor layer reacts with the recording liquid to cause a change in resistance value due to corrosion of the heating resistor layer, or damage or destruction of the heating resistor layer.

For this purpose, conventionally, the heat generating resistance layer is made of an inorganic material having relatively excellent characteristics as a heat generating resistance material such as an alloy such as NiCr and a metal boride such as ZrB ₂ and HfB ₂ . By providing a protective layer made of a material having excellent oxidation resistance such as SiO ₂ on the heating resistor layer made of these materials, it is possible to prevent the heating resistor layer from directly contacting the recording liquid, It has been proposed to solve the above-mentioned problems and improve reliability and durability in repeated use.

FIG. 8A is an enlarged plan view of a nozzle portion of such a conventional ink jet recording head, and FIG.
FIG. 8B is a cross-sectional view taken along line AA of FIG.

In forming the thermal energy generating means of the ink jet recording head, a desired substrate 10 is generally used.
After forming the heat storage layer 102 and the heat generating resistance layer 103 on 1, the electrode 104 and the protective layer 105 are sequentially laminated. Such a protective layer 105 of the thermal energy generating means is provided with such a heat generating layer in order to sufficiently fulfill various functions as the protective layer 105 such as prevention of damage of the heating resistance layer 103 and prevention of short circuit between the electrodes 104 as described above. Resistance layer 10
It is required to uniformly cover (cover) a required portion of the electrode 3 and the electrode 104 without having a layer defect such as a pinhole.

Further, in such an ink jet recording head, as described above, since the electrode 104 is generally formed on the heating resistor layer 103, a step (step) portion 106 is formed between the electrode 104 and the heating resistor layer 103. However, since the thickness of the protective layer 105 is likely to be uneven in such a step portion 106, the step portion 106 is sufficiently covered so that an exposed portion is not generated (step coverage). First, the formation of the protective layer 105 must be performed. That is, when an insufficient non-uniform portion 110 occurs in the step coverage and a discontinuous portion occurs in the protective layer 105, the exposed portion of the heating resistor layer 103 and the recording liquid come into direct contact, and the recording liquid is In some cases, the recording layer may be decomposed, or the recording liquid may react with the heating resistor layer 103 to destroy the heating resistor layer 103. In addition, such a step 10
6, the film quality is likely to be non-uniform. Such non-uniform film quality is caused by the repetition of heat generation.
Causes a partial concentration of the thermal stress generated in the heat-resistant layer 103, which causes a crack (crack) in the protective layer 105.
Was sometimes destroyed. Further, the recording liquid may enter through the pinhole and break the heat generating resistance layer 103 in some cases. In particular, when a pinhole is formed due to insufficient formation of the step coverage, most of the heaters are destroyed and the reliability may be significantly reduced.

In order to solve such a problem, the thickness of the protective layer 105 is increased (normally, 1.5 times or more the thickness of the electrode 104) to improve step coverage and reduce pinholes. Although the thickening of the protective layer 105 contributes to the reduction of step coverage and pinholes, the thickening of the protective layer 105 hinders the supply of heat to the recording liquid. A new problem has arisen.

That is, the heat generated in the heat generating resistance layer 103 is transmitted to the recording liquid through the protective layer 105, and the heat is generated between the surface of the protective layer 105 and the heat generating resistance layer 103, which is the surface where the heat acts. Is increased by increasing the thickness of the protective layer 105.
03 needs to be loaded more than necessary. 1. disadvantageous for power saving 2. Unnecessary heat accumulates in the substrate, resulting in poor thermal response. Since excessive power is applied, the heating resistance layer 103
In some cases, there was a problem that the durability of the steel became poor.

Such a problem can be overcome by reducing the thickness of the protective layer 105. However, in the conventional method of manufacturing an ink jet recording head using a film forming method such as sputtering or vapor deposition for forming the protective layer 105, there is no step. Due to poor coverage and the like, there are the drawbacks in durability described above, and it has been difficult to make the protective layer 105 thin.

It is also known that, when recording with the above-described ink jet recording head, the more rapidly the recording liquid is heated, the more the foaming stability of the recording liquid is improved. That is, the electric signal applied to the thermal energy generating means, generally a rectangular electric pulse, the shorter the pulse width, the better the foaming stability of the recording liquid,
As a result, the ejection stability of the flying droplet is improved, and the recording quality is improved. However, in the conventional ink jet recording head, as described above, the protection layer 105
Must be increased, the thermal resistance of the protective layer 105 increases, and more heat than necessary must be generated by the thermal energy generating means. For this reason, it is difficult to shorten the pulse width, and the improvement of the recording quality is naturally limited.

Therefore, in order to solve the above-mentioned problems, in the etching step of the electrode layer, as described in Japanese Patent Application Laid-Open No. 04-320847, the resist is etched while the resist is receded, so that the etched cross-sectional shape is tapered. A method for improving the step coverage of an upper protective layer is disclosed.

In Japanese Patent Application Laid-Open No. 04-320848, in the electrode layer etching process, the etching is performed partway, the resist is etched, the pattern is retreated, and the etching is performed, so that the cross-sectional shape is stepwise. Discloses a method for improving the step coverage of the upper protective layer by reducing the step of each step.

[0019]

However, the method disclosed in Japanese Patent Application Laid-Open No. 04-320847 uses a method of etching while retreating a resist, but has the following problems.

That is, in order to perform etching while retreating the resist, it was necessary to pay attention to the resist material and the baking conditions. When the material of the resist changes, the retreat speed changes, and a desired taper angle may not be obtained. Further, if the baking conditions change, the resist retreat speed changes, and a desired taper angle may not be obtained.

Further, in order to perform etching while retreating the resist, it is necessary to strictly control the temperature of the trimethyl hydroxide solution, and when the temperature changes, the ratio between the etching rate of the resist and the etching rate of the electrode material changes. Therefore, a desired taper angle may not be obtained.

In particular, when the upper protective layer is thinner than the electrode layer, more strict control of the taper angle is required.

Further, in the method disclosed in Japanese Patent Application Laid-Open No. 04-320848, the resist is etched with a trimethyl hydroxide solution. However, since the resist etching rate changes depending on the resist material, the resist material is restricted. There was a case. Moreover, since the etching rate of the resist changes depending on the baking conditions of the resist, strict control of the baking conditions is required, and strict control of the temperature of the trimethyl hydroxide solution of the etching solution is required in some cases. Further, the electrode may not be formed into a desired shape because the trimethyl hydroxide solution may etch the electrode.

Therefore, the present invention has a high thermal response and
It is an object of the present invention to provide a method for manufacturing a substrate for an inkjet recording head, a method for producing an inkjet recording head, an inkjet recording head, and an inkjet recording apparatus with improved durability.

[0025]

In order to achieve the above object, a method of manufacturing a substrate for an ink jet recording head according to the present invention comprises: a heating resistor layer which generates heat when electric power is applied; and a heating resistor layer laminated on the heating resistor layer. A plurality of thermal energy generating means for supplying discharge energy to the recording liquid, and a plurality of thermal energy generating means for protecting the thermal energy generating means. In the method for manufacturing a substrate for an ink jet recording head having a protective layer formed on a means, an etching step of etching the electrode layer to a halfway thickness thereof, and after the etching step, laminated on the electrode layer, A resist retreating step of retreating the resist for patterning the electrode layer by dry etching; and A polymer removing step of removing the polymer attached to the electrode layer, and after the polymer removing step, a wet etching step of wet etching the electrode layer remaining etched in the etching step until the heating resistor layer is exposed, A repeating step of repeating the etching step, the resist retreating step, the polymer removing step, and the wet etching step at least once, and after the repetition step, forming a protective layer on each of the thermal energy generating means. And forming.

In the method of manufacturing a substrate for an ink jet recording head according to the present invention as described above, the electrode layer is firstly etched to a middle of the thickness of the electrode layer by wet etching or dry etching, and then the resist is dry-etched. After retreating and further removing the polymer adhered to the electrode layer in the resist retreating step, the electrode layer left in the first etching by wet etching is etched until the heat generating resistance layer is exposed. Moreover,
After repeating these steps at least once, a protective layer is formed on the thermal energy generating means. As described above, the electrode etching is performed in at least two steps with the step of retreating the resist by dry etching interposed therebetween, so that the end face of the electrode is stepped to reduce the height difference between the electrode and the heating resistor layer stepwise. It can be formed into a shape. After the step-shaped portion is formed, a protective layer is formed on the electrode, the step-shaped portion, and the heating resistor layer. Therefore, an electrode or a discontinuous portion that exposes the heating resistor layer is formed on the protection layer. Can be prevented.

Before the wet etching step, by removing the polymer adhered to the electrode layer in the resist retreating step, the polymer adhered by the dry etching gas remains. It can be prevented that the etching of the interface does not progress.

According to the method of manufacturing an ink jet recording head of the present invention, a heating resistor layer that generates heat when power is applied and an electrode formed by etching an electrode layer laminated on the heating resistor layer are formed. A plurality of thermal energy generating means for supplying discharge energy to the recording liquid; and a protective layer formed on each thermal energy generating means for protecting each thermal energy generating means. Manufacturing of an ink jet recording head including a step of joining a base and a top plate provided with a groove corresponding to each of the thermal energy generating elements to form a liquid flow path communicating with a discharge port from which a recording liquid is discharged. In the method,
An etching step of etching halfway through the thickness of the electrode layer, and after the etching step, a resist retreating step of retreating a resist for patterning the electrode layer, which is laminated on the electrode layer, by dry etching, A polymer removing step of removing a polymer attached to the electrode layer in a resist retreating step, and after the polymer removing step, etching of the electrode layer remaining in the etching step until the heating resistor layer is exposed is etched by wet etching. A repeating step of repeating the wet etching step, the etching step, the resist retreating step, the polymer removing step, and the wet etching step at least once or more. Forming a protective layer thereon. And wherein the Mukoto.

In the method of manufacturing an ink jet recording head according to the present invention as described above, the electrode is etched in at least two steps with a step of retreating the resist by dry etching, so that the end face of the electrode is After forming a step-like shape in which the height difference between the heating resistor layer and the heating resistor layer is gradually reduced, a protective layer is formed on the electrode, the step-shaped portion, and the heating resistor layer. Can be prevented from being formed.

An ink jet recording head according to the present invention is manufactured by the above-described method for manufacturing an ink jet recording head.

An ink jet recording apparatus of the present invention holds a conveying means for conveying a recording medium, an ink jet recording head of the present invention which discharges ink and performs recording on the recording medium, and includes the recording medium. And holding means for reciprocating in a direction substantially perpendicular to the transport direction.

Since the ink jet recording apparatus of the present invention configured as described above uses the ink jet recording head of the present invention, the protective film is formed on the heating resistance layer, on the electrode, and on the stepped portion formed on the end face of the electrode. The recording liquid and the electrode of the ink jet recording head substrate, or the heating resistor, are formed continuously without the formation of an electrode or a discontinuous portion that exposes the heating resistor layer on the protective layer. The contact with the layer can be prevented.

[0033]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of a part of a substrate for an ink jet recording head which is an example of the present invention, and FIG. 2 is a sectional view taken along line AA in FIG.

The ink jet recording head substrate of the present embodiment is partitioned by a plurality of nozzle walls 9 formed on a top plate 16 (not shown) so that the ejection ports 2 from which ink is ejected are formed.
A plurality of liquid flow paths 17 communicating with each other (see FIG. 5);
A substrate 1 made of Si, and SiO ₂ formed on the substrate 1
Heat storage layer 2 made of HfB ₂ formed on heat storage layer ₂
A heating resistor layer 3 made of Al, an electrode 4 made of Al formed in a region on the heating resistor layer 3 excluding the heating action part 8, and an upper protective layer 5 covering the heating resistor layer 3 and the electrode 4.

The tapered portion 10 is formed at the step 12 of the heat generating portion 8.
Is formed, the thickness of the upper protective layer 5 at the step portion 12 is substantially uniform with respect to the upper surface of the electrode 4 and the heat generating portion 8.

Hereinafter, an example of a method of manufacturing the ink jet recording head substrate shown in FIGS. 1 and 2 will be described with reference to FIGS. 3A to 3F and a flowchart shown in FIG.

First, for example, as shown in FIG.
An insulator (oxide or the like) is formed as a heat storage layer 2 on a substrate 1 made of a desired material such as glass, ceramics, or plastic by a thermal oxidation method or a CVD method.
Then, the heating resistance layer 3 is formed by using a vacuum evaporation method, a sputtering method, or the like. Next, an electrode layer 4a is formed on the heating resistor layer 3 by using a vacuum evaporation method, a sputtering method or the like (Step 301).

Next, as shown in FIG. 3B, a resist 11 is formed on the electrode layer 4 by using a well-known photolithography technique.
a is patterned (step 302).

Next, as shown in FIG.
a and a heating resistor layer 3 performs first-step etching to the electrode layer 4a having a thickness of t ₁ is the thickness t ₂ remains by etching (step 303). The etching may be performed by a wet etching method or a dry etching method.

Next, as shown in FIG. 3D, the pattern of the resist 11 is retreated by a distance S by dry etching (step 304). The dry etching of the resist 11 may be any method other than the plasma etch method or the RIE method, as long as it can set conditions for etching only the resist 11. The etching gas may be only O ₂ , but in some cases, a mixed gas of O ₂ and CF ₄ may be used.

After the completion of the dry etching, the substrate is immersed in a polymer removing solution containing dimethyl sulfoxide as a main component,
The polymer attached to the electrode layer 4a is removed by dry etching (step 305). The polymer remover is generally a polymer remover containing dimethyl sulfoxide as a main component, but may be another polymer remover.

As described above, the polymer is removed by dry etching the resist 11 for the following reasons.

That is, after the dry etching is completed without removing the polymer (FIG. 5A), the wet etching is performed as it is.
In particular, a polymer resulting from the dry etch gas is formed at the interface with the resist 11, and thereafter, in the wet etching, the etching of the portion where the polymer is formed does not progress, and the abnormal etch portion 13 having a shape as shown in FIG. Is formed. When the upper protective layer 5 is formed on the abnormally etched portion 13 having such a shape, as shown in FIG. 5C, a portion where step coverage deteriorates, that is, a discontinuous step coverage where the film quality of the protective layer is poor. The defective portion 14 is formed.

Therefore, instead of the state shown in FIG.
In order to obtain a cross-sectional shape as shown in (e), after the dry etching of the resist 11 is completed, that is, before the wet etching is performed, a polymer removing process is performed using a polymer removing agent containing dimethyl sulfoxide as a main component. FIG.
As shown in (e), the second stage etching of the electrode layer 4a is performed (Step 306). That is, the remaining thickness t ₂ electrode layer 4a by wet etching, the heat generating resistor layer 3 to be exposed. By performing two-stage etching on the electrode layer 4a, the tapered portion 10 is formed in the step portion 12.

Next, the resist 11 is peeled off (step 3).
07). As described above, at least one of the thermal energy generating means including at least one pair of electrodes 4 electrically connected to each other.
The pair is completed.

[0047] Finally, as shown in FIG. ₃ (f), Si 3
An upper protective layer 5 made of a desired material such as N ₄ , SiO ₂ , SiON, Ta ₂ O ₅ or the like is formed by vacuum evaporation, sputtering, CVD or the like (step 308).

The upper protective layer 5 does not need to be made of a single material, but may be made of a plurality of materials made of two or more materials for the purpose of, for example, improving cavitation resistance.

The etching cross-sectional shape of the electrode 4 is optimized,
In order to form the upper protective layer 5 continuously and optimize the step coverage, it is important to make the electrode layer 4a stepwise and reduce one step. It is important that the thickness be 1 / 1.5 or less of the film thickness, but it is not limited to this. In the present embodiment, the example in which the electrode layer 4a is etched in two steps to form the two-stepped portion 12 has been described. However, in order to reduce the step, three or more steps may be used if necessary. In such a case, the etching of the electrode 4 and the etching of the resist 11 may be repeated twice or more.

Next, as described above, the upper protective layer 5
Is a schematic view of an example of an ink jet recording head using an ink jet recording head substrate continuously formed on the heating resistance layer 3, the electrode 4, and the step 12 formed on the end face of the electrode 4. FIG. 6 shows a simple perspective view.

FIG. 6A is an external perspective view of the top plate 16 to be joined to the ink jet recording head base 30 of the present embodiment, as viewed from the joining surface side.

The top plate 16 has a plurality of liquid flow grooves 17a for forming the liquid flow paths 17 by being joined to the ink jet recording head base 30, and a liquid supplied from the outside. Each liquid flow channel 17 to be supplied to the flow channel 17a
groove 1 for the common liquid chamber, which is a groove for the common liquid chamber 19 communicating with a
9a are formed. Between the liquid flow grooves 17a is a flow wall 9 that partitions the liquid flow grooves 17a.

After the top plate 16 is sufficiently aligned with the base 30 for the ink jet recording head, it is joined, and a recording liquid supplied from a liquid supply system (not shown) is introduced into the head. Connect the liquid supply pipe 20,
An ink jet recording head 31 as shown in FIG. 6B in which the common liquid chamber 19, the liquid flow path 17 and the discharge port 21 are formed is obtained. In addition, the inkjet recording head 31
Although the input side electrode 4b is used as an individual electrode so that each of the thermal energy generating means can be selectively heated, the return side electrode 4c is used as a common electrode to simplify the electrode configuration.

The ink jet recording head 31 is configured such that electric energy is input to each of the ejection energy generating elements of the heat acting section 8 composed of the electrode 4 and the heating resistor layer 3,
The liquid supplied from the outside that comes into contact with each of the discharge energy generating elements causes a state change accompanied by a steep volume change (generation of bubbles), and the liquid is discharged from the discharge port 21 by the action force based on the state change of the liquid. The discharged liquid is made to adhere to the recording medium to form an image.

Although not particularly described, the discharge port 21
The formation of the liquid flow path and the like is not necessarily performed by using a grooved plate as illustrated in FIG. 6, but may be performed by patterning a photosensitive resin or the like. Further, the present invention is not limited to a multi-array type ink jet recording head having a plurality of liquid discharge ports as described above, and is of course applicable to a single array type ink jet recording head having one liquid discharge port. You can do it.

Next, FIG. 7 shows an external perspective view of an example of an ink jet recording apparatus to which the ink jet recording head of the present invention can be applied.

The main body chassis 212 has a guide shaft 2
The carriage 208 is mounted on a guide shaft 209 so as to be slidable in the direction of arrow B. The carriage 208 includes a timing belt 210 stretched between a driving pulley 213 and an idler pulley 214.
A part of the carriage 208 is fixed, and can reciprocate in the arrow B direction along the guide shaft 209 according to the rotation of the carriage motor 211. In the present embodiment, the cartridge 201 performs recording on the recording paper 204 by ejecting ink,
The ink jet recording head 31 and the ink tank 15, each of which is formed downward in the drawing, are integrated.

The cartridge 201 is detachably mounted on the carriage 202, and is electrically connected to a recording controller 37 (not shown) via a flexible cable 202 for transmitting and receiving a current and a signal for driving the cartridge 201.

Further, the ink jet recording apparatus has a cap unit 203 having recovery means for recovering the ink ejection characteristics of the ink jet recording head 31. The cap unit 203 includes a cap member 206 corresponding to the ink jet recording head 31 and a wiper blade 207 made of a member such as rubber. The ink jet recording apparatus having such a configuration performs the serial scan of the ink jet recording head 31 in a direction (main scanning direction) B ′ orthogonal to the transport direction A ′ of the recording medium to correspond to the number of nozzles of the ink jet recording head 31. The recording medium having a width equal to the recording width is intermittently conveyed at the time of non-recording.

As described above, according to the method of manufacturing a substrate for an ink jet recording head of the present embodiment, the electrode layer 4a is first etched to a halfway thickness of the electrode layer 4a by wet etching or dry etching. Next, the resist is receded by dry etching, and further, the electrode layer 4a left in the first etching by wet etching is etched until the heat generating resistance layer 3 is exposed. Further, after these steps are repeated at least once, the upper protective layer 5 is formed on the thermal energy generating means. As described above, the etching of the electrode 4 is performed in at least two steps with the step of retreating the resist 11 by dry etching interposed therebetween, so that the end surface of the electrode 4 is made to have a step difference in height between the electrode 4 and the heating resistor layer 3. For example, the step portion 1 including the tapered portion 10
2 can be formed. After the step 12 is formed, the upper protection layer 5 is formed on the electrode 4, the step 12, and the heating resistor layer 3, so that the electrode 4 or the heating resistor layer 3 is exposed on the upper protection layer 5. It is possible to prevent a discontinuous portion such as a step coverage defective portion from being formed.

[0061]

EXAMPLES Next, examples of the embodiment of the present invention will be described, but the present invention is not limited to these examples.

In this example, the ink jet recording head of the above-described embodiment shown in FIG. 6 was manufactured. In addition, a method of manufacturing a substrate for an ink jet recording head used in this ink jet recording head will be described with reference to FIG. 3 of the above-described embodiment, and therefore, the same reference numerals are used as in the above-described embodiment.

First, as shown in FIG. 3A, a heat storage layer 2 made of SiO ₂ having a thickness of 5 μm was formed on a Si substrate 1. Then, a heating resistance layer 3 made of HfB ₂ was formed to a thickness of 1300 ° by a sputtering method.

Next, on the heating resistance layer 3, A
An l layer was formed to a thickness of t ₁ = 4000 ° by a sputtering method.

Next, as shown in FIG. 3B, the resist 11 is patterned by using a known photolithography technique.

Next, as shown in FIG.
a and the heating resistor layer 3 were etched to a thickness of 4000
The first-stage etching is performed by wet etching to a thickness of 0.2 μm so that the electrode layer 4a of
m etching is performed. A mixed system of nitric acid, phosphoric acid and acetic acid is used as an etching solution.

Next, as shown in FIG. 3D, the etching pattern of the resist 11 is retreated by a retreat amount S by using a plasma etching apparatus and using O ₂ as a gas. The receding amount S is 0.5 μm.

Next, immersion treatment is performed with a polymer removing solution SST-A1 (manufactured by Tokyo Ohka) containing dimethyl sulfoxide as a main component to remove the polymer adhered to the electrode layer 4a.

Next, as shown in FIG. 3E, an electrode layer 4 is formed by using a mixed system of nitric acid, phosphoric acid and acetic acid as an etching solution.
The remaining 2000 ° of a is removed by wet etching, and then the resist 11 is peeled off.

As described above, a heat energy generating means having a circuit pattern having a size of 30 μm in width × 150 μm in length and a resistance value of 100 Ω including the electrode 4 was formed as described above.

Next, as shown in FIG.
The RF power is 1 kW and the pressure is
Under the formation condition of 0.13 Pa, on the thermal energy generating means
SiO _TwoUpper protective layer 5 made of 0.3 μm thick
Done.

Thereafter, in order to improve the cavitation resistance of the first protective layer 5, a second protective layer (not shown) made of Ta is formed on the upper protective layer 5 by using the above-mentioned RF sputtering apparatus. It was formed to a thickness of 5000 mm.

The protective layer obtained as described above was of good quality with good step coverage and no layer defects such as pinholes.

The substrate for the ink jet recording head has:
The glass top plate 16 was joined after sufficient alignment, and a liquid supply pipe 20 was further connected thereto to form an ink jet recording head 31 shown in FIG.

In FIG. 6, the width is 40 μm and the height is 4 μm.
The grooves serving as the 0 μm liquid flow path 17 and the common liquid chamber 19 were formed by cutting using a micro cutter.

The individual electrodes 12 and the common electrode 11 are provided with a lead substrate (not shown) having electrode leads for applying a desired pulse signal from outside the head, and recording is performed based on the signals. It is.

The ink jet recording head thus manufactured is (1) reduced in power consumption, (2) improved in thermal response, and (3) driven with a shorter pulse width than the conventional one. , Improved performance such as good durability was observed. Further, based on the foaming stability by driving the short pulse, the ejection stability of the recording liquid was improved, and the recording quality was improved. Further, the recording durability was good.

[0078]

As described above, according to the present invention, the electrode layer is first etched to a point in the thickness of the electrode layer,
Next, the resist is receded by dry etching,
Further, the electrode layer left by the first etching by wet etching is etched until the heat generating resistance layer is exposed. Further, after repeating these steps at least once or more, a protective layer is formed on the thermal energy generating means. For this reason, the end face of the electrode can be formed in a step shape that gradually reduces the height difference between the electrode and the heating resistor layer, and then the protective layer is formed on the electrode, on the step-shaped portion, and on the heating resistor layer. This prevents formation of a discontinuous portion that exposes an electrode or a heating resistor layer in the protective layer. Therefore, it is not necessary to form a thick protective film so that a discontinuous portion is not formed, so that the thermal responsiveness of the ink jet recording head substrate can be improved,
In addition, since the destruction of the heating resistance layer due to direct contact between the recording liquid and the heating resistance layer is prevented, the durability can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a part of a substrate for an ink jet recording head which is an example of the present invention.

2 is a cross-sectional view of the substrate for an ink jet recording head shown in FIG. 1, taken along the line AA in FIG. 1;

FIG. 3 is a diagram illustrating an example of a method for manufacturing a substrate for an inkjet recording head according to the present invention.

FIG. 4 is a flowchart illustrating an example of a method of manufacturing a substrate for an inkjet recording head according to the present invention.

FIG. 5 is a diagram showing an abnormal etch portion and a defective step coverage formed when a substrate for an ink jet recording head is manufactured without removing a polymer.

FIG. 6 is a schematic external perspective view of an example of an inkjet recording head using the inkjet recording head substrate of the present invention.

FIG. 7 is a perspective view of an example of an inkjet recording apparatus to which the inkjet recording head of the present invention can be applied.

FIG. 8 is an enlarged plan view of a nozzle portion of a conventional ink jet recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Thermal storage layer 3 Heat generating resistance layer 4 Electrode 5 Upper protective layer 8 Heat acting part 9 Flow path wall 10 Tapered part 11 Resist 12 Stepped part 13 Abnormal etch part 14 Step coverage defect part 16 Groove plate 17 Liquid flow path 17a Liquid flow Road groove 19 Common liquid chamber 19a Common liquid chamber groove 20 Liquid supply pipe 21 Discharge port 30 Ink jet recording head base 31 Ink jet recording head 201 Cartridge 202 Flexible cable 203 Cap unit 204 Recording paper 205 Feed tray 206 Cap member 207 Wiper Blade 208 Carriage 209 Guide shaft 210 Timing belt 211 Carriage motor 212 Main chassis 213 Drive pulley

Claims (4)

[Claims] 1. A method of supplying discharge energy to a recording liquid, comprising: a heating resistor layer that generates heat when electric power is applied; and an electrode formed by etching an electrode layer stacked on the heating resistor layer. A plurality of heat energy generating means for protecting the heat energy generating means,
In the method of manufacturing a substrate for an ink jet recording head having a protective layer formed on each of the thermal energy generating means, an etching step of etching the electrode layer to a halfway thickness thereof; Laminated,
A resist retreating step of retreating a resist for patterning the electrode layer by dry etching, a polymer removing step of removing a polymer attached to the electrode layer in the resist retreating step, and after the polymer removing step, the heating resistance layer Until is exposed, a wet etching step of etching the electrode layer left in the etching step by wet etching, the etching step, the resist receding step, the polymer removing step, and the wet etching step A method for manufacturing a substrate for an ink jet recording head, comprising: a repetition step of repeating at least one or more times; and, after the repetition step, forming a protective layer on each of the thermal energy generating means. 2. A method for supplying discharge energy to a recording liquid, comprising: a heating resistor layer that generates heat when electric power is applied; and an electrode formed by etching an electrode layer stacked on the heating resistor layer. A plurality of heat energy generating means for protecting the heat energy generating means,
The recording liquid is discharged by joining a substrate for an ink jet recording head having a protective layer formed on each of the thermal energy generating means and a top plate provided with a groove corresponding to each thermal energy generating element. In a method for manufacturing an ink jet recording head including a step of forming a liquid flow path communicating with a discharge port, an etching step of etching the electrode layer halfway through a thickness thereof; ,
A resist retreating step of retreating a resist for patterning the electrode layer by dry etching, a polymer removing step of removing a polymer attached to the electrode layer in the resist retreating step, and after the polymer removing step, the heating resistance layer Until is exposed, the wet etching step of etching the electrode layer remaining etched in the etching step by wet etching, the etching step, the resist receding step, the polymer removing step, the wet etching step A method for manufacturing an ink jet recording head, comprising: a repetition step of repeating at least one or more times; and, after the repetition step, a step of forming a protective layer on each of the thermal energy generating means. 3. An ink jet recording head manufactured by the method for manufacturing an ink jet recording head according to claim 2. 4. A transporting means for transporting a recording medium, and an ink jet recording head according to claim 3, which discharges ink and performs recording on said recording medium, and transports the recording medium. And a holding unit that reciprocates in a direction substantially perpendicular to the ink jet recording apparatus.