JP3387871B2 - Micro-shaped component 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 relates to an ink jet head, and more specifically, an ink jet head particularly suitable for high-density printing, a method of manufacturing the ink jet head, and a fine shape portion having a fine shape portion typified by an ink chamber of the ink jet head. The present invention relates to a shaped part and a manufacturing method thereof. INDUSTRIAL APPLICABILITY The inkjet head of the present invention can be advantageously used in a head section of an inkjet printer which has been widely used in recent years.

[0002]

2. Description of the Related Art In recent years, in office automation (OA) equipment such as word processors, personal computers, facsimile machines, various measuring instruments such as medical measuring instruments, and other devices, output information from these devices is highly dense. Inkjet printers are widely used for printing. Inkjet printers
As is well known, this is for ejecting ink droplets from the head portion and directly adhering the ink droplets to a recording medium such as recording paper to perform monochrome or color printing. Inkjet printers can print even when the recording medium is a three-dimensional object, plain paper can be used as the recording medium, so the running cost is low, head mounting is easy, and transfer / fixing etc. It has many advantages such as no process required, easy colorization, and clear color printing. Inkjet heads can be classified into various types according to the driving method of ejecting ink droplets from them. For example, a piezo type inkjet head uses a piezoelectric element (piezo element) as a pressurizing means. By utilizing the electrostrictive effect of the piezoelectric element, a pressure wave is generated in the ink chamber filled with ink in the head portion, and thereby ink is ejected from the nozzle in the head portion. In addition, the bubble jet type inkjet head uses a heating element as a pressurizing means, and heats the heating element to generate bubbles, thereby ejecting ink from the nozzles of the head portion. Further, an electrostatic suction type inkjet head which ejects ink droplets by electrostatic suction force is also known. The ink jet head of the present invention can be advantageously applied to ink jet heads of these types and other types.

A conventional ink jet head normally has a plurality of ink chambers (fine protrusions or openings) arranged at equal intervals, which serve as an ink flow path and a pressure chamber for ejecting ink. A finely shaped portion), a nozzle plate attached to the tip of the ink chamber and equipped with nozzles for ejecting ink corresponding to each ink chamber, and ink in the ink chamber according to the request for printing. Is configured to include a pressurizing means capable of pressurizing. The pressurizing unit has a driving body that generates a driving force for pressurizing the ink chamber, and the driving body has the above-described structure.
It may be a piezoelectric element or a heating element.

The structure of the inkjet head will be described in more detail. For example, the piezo type inkjet head 10 is composed of several members, as can be seen from FIG. The ink chamber member 11 has a plurality of ink chambers (fine shaped portions) 12 that serve as an ink flow path and a pressure chamber for ejecting ink.
have. A nozzle plate 13 having nozzles 14 arranged corresponding to the respective ink chambers 12 is attached to the tip of the ink chamber member 11. As described above, the ink pressurized in the ink chamber 12 can be ejected from the holes of the nozzle 14 in the form of droplets. In the illustrated ink chamber member 11, a pressurizing unit is attached to the open surface of the ink chamber 12. In the illustrated example, the pressurizing means includes a diaphragm 15 serving as a diaphragm for changing the volume of the ink chamber 12, a piezoelectric element 17 serving as a driving body for distorting the diaphragm 15, and a piezoelectric element. 17
And a base 18 for fixing the.

The ink chamber member 11 has a plurality of deep groove-shaped ink chambers 12 which also serve as ink flow paths and pressurizing chambers for ejecting ink. Corresponds to the perforated nozzle 14, 1
It is designed such that one nozzle is arranged in each ink chamber. In addition, each ink chamber 1
Reference numerals 2 are arranged in parallel with each other and at the same intervals by partition walls that separate adjacent ink chambers. Here, in order to increase the resolution of the inkjet head, it is necessary to narrow the interval between the ink chambers 12 formed in the ink chamber member 11. In addition, the ink chamber member 11 and the nozzle plate 13 can usually be joined using an adhesive.

The diaphragm 15 is a component peculiar to the piezoelectric ink jet head 10. When the piezoelectric element 17 expands and contracts due to the electrostrictive effect, the diaphragm 15 bends, causing a volume change in the ink chamber 12. When the volume in the ink chamber 12 becomes smaller, the ink filled in the chamber is pressurized, and a part of the ink is sequentially ejected from the nozzle 14 as an ink droplet. The diaphragm 15 is generally composed of a thin plate having a thickness of about 3 to 5 μm, and an island 16 formed on one surface of the thin plate and having a height of about 20 μm. The island 16 is for reliably transmitting the strain to the ink chamber 12 when the piezoelectric element 17 expands and contracts due to the electrostrictive effect. Therefore, the island 16 is arranged so as to overlap the ink chamber 12 and the piezoelectric element 17 corresponding to each. The ink chamber member 11 and the diaphragm 15 can also be bonded with an adhesive.

The piezoelectric element 17 corresponds to each ink chamber 12 of the ink chamber member 11 and also the other ink chambers 12.
Are separated from each other in order to prevent the influence on. These separated piezoelectric elements 17 are fixed on a base 18. The piezoelectric element 17 is generally manufactured by first bonding the piezoelectric element which is not separated to the base with an adhesive, and then selectively separating only the piezoelectric element by cutting. After forming the piezoelectric element and the base integrated with each other in this way, the piezoelectric element and the island formed on the diaphragm corresponding thereto can be bonded with an adhesive.

In the above and other ink jet heads, the performance of the ink chamber, which is a finely-shaped portion including fine protrusions or openings, which doubles as an ink flow path and a pressure chamber for discharging ink, is Performance is very important as it directly affects printing characteristics. First, looking at the ink chamber member that constitutes the ink chamber, the ink chamber member of the conventional piezoelectric inkjet head is formed by injection molding an organic material such as "epox (trade name of epoxy resin)". It was common. However, the ink chamber member made of an organic material has a drawback that it is poor in rigidity, and therefore it is impossible to apply sufficient pressure to the ink at the time of pressurization.

It is also practiced to use oxide powder such as ZrO _{2 in place of the} organic material and form the powder into the ink chamber member according to a processing method called powder injection molding method. This method, however, requires the use of molds,
Further, since a very large pressure is applied when the raw material powder is filled in the mold, it is difficult to use a molding mold having a fine structure enough to form a fine ink chamber.

As a processing method suitable for forming a fine ink chamber, an etching method can be mentioned. For example, by using this processing method, it is possible to finely form a groove-shaped pattern on the surface of a metal plate having a thickness of several hundreds of μm.
However, even in this method, in terms of increasing the density, it is not possible to say that the groove is formed with a width substantially equal to the plate thickness, and the groove is sufficiently effective. Further, in the case of the etching method, since the formed groove penetrates the metal plate, if the metal plate is used as the ink chamber member, one surface of the metal plate is closed with the through grooves. Therefore, it is necessary to attach additional members for the purpose, which complicates the manufacturing process.

As another method for forming an ink chamber member, Japanese Patent Publication No. 62-59672 and Japanese Patent Publication No. 2-4.
A photolithography method using a photosensitive resin generally called a photoresist or a resist as disclosed in Japanese Patent No. 2670 is also known. In this method, the entire surface of the substrate on which the ink chamber is to be formed is coated with a resist, and then the obtained resist film is selectively exposed to appropriate light in accordance with the pattern of the ink chamber to be obtained. After exposure, by dissolving and removing the area that was not insolubilized by exposure with a developer,
It is possible to obtain a substrate provided with a desired ink chamber composed of a cured resist pattern. The photolithography method using a resist is a technique widely used in the manufacture of semiconductor devices such as LSI and VLSI.

FIG. 2 is a cross-sectional view showing in sequence the formation of an ink chamber using a generally used photolithography method. First, as shown in FIG. 2A, a resist is applied to the surface of the substrate 31 to form a resist film 32, and then the resist film 32 is pattern-exposed through a photomask 33. Since the resist used here is a negative resist having sensitivity to ultraviolet rays, the photomask 33 is made of glass capable of transmitting ultraviolet rays in a portion corresponding to the partition wall of the ink chamber, and the other portions are exposed to ultraviolet rays. A chromium film is applied to prevent the permeation of the chrome. The light beam for exposure indicated by an arrow is an ultraviolet ray from a light source (not shown).

As a result of the pattern exposure, the exposed region of the resist film 32 is made insoluble in the developing solution. After that, the resist film 32 after the exposure is developed with an appropriate developing solution, and the unexposed region (soluble region) is dissolved and removed. As shown in FIG. 2B, a cured resist pattern 32 corresponding to the desired shape of the ink chamber is obtained. Here, the remaining resist pattern 32 is
The substrate 31 functions as a partition member that partitions adjacent ink chambers, and the substrate 31 functions as a bottom plate member. Although the negative resist is used as the resist in the illustrated example, a positive resist that solubilizes and removes the exposed region is used instead.

In the same manner as the piezo type ink jet head as described above, the ink chamber of the bubble jet type ink jet head, which is another type, can be manufactured. That is, the ink chambers and nozzles are basically common in the heads of these two methods, except that the piezoelectric element and the diaphragm are not used in the bubble jet method, and instead, they are placed on a highly rigid substrate. It has a heating element and associated members arranged corresponding to each ink chamber.

The conventional ink jet head has been described above. However, these inkjet heads cannot cope with high-density printing which has been particularly demanded in recent years. In recent years, in the field of printers, high-density printing in which the number of dots per inch (dpi) is 180 or more is required. As a matter of course, also in the inkjet head, the distance between the ink chambers of the head portion, and hence the distance between the nozzles, is required to be a narrow length corresponding to at least 180 dpi. Here, the “interval equivalent to 180 dpi” is 141 when expressed in a specific length.
This means that the ink chambers and nozzles are formed at intervals of μm (the distance d between adjacent ink chambers 12 in FIG. 1).
And the spacing d between adjacent nozzles 14). That is, in the ink chamber member, 141 μm
It is necessary that the ink chamber and the partition member that separates the ink chamber are formed within the limited length. For example, when the ratio of the width of the ink chamber to the thickness of the partition member is 1: 1, the width of the ink chamber is 70.5 μm and the thickness of the partition member is 70.5 μm. In this way, the width of the ink chamber becomes narrower as the printing density becomes higher. However, even if it is possible to achieve high density by narrowing the width of the ink chamber, good printing quality cannot be obtained if the dots of ink printed on the recording medium are too small. In order to avoid deterioration of print quality, keep the ejected ink dots large, in other words,
It is necessary to eject a sufficient amount of ink from each nozzle. For that purpose, it is preferable that the volume of the ink chamber is large, and thus it is required to provide the ink chamber in which the height of the partition member is large.

Returning to the formation of the ink chamber member again, the injection molding method most commonly used in the prior art has a risk of destroying the mold itself in the case of a fine structure.
Since it cannot be molded with high precision, 120 dpi
The limit is the formation of a fine structure corresponding to a print density of a certain degree. In addition, since it is easy for the etching method to finely process what has a planar shape, it is possible to sufficiently perform patterning of about 180 dpi. However, generally in the etching method, the width that can be patterned by the etching method is affected by the thickness of the member to be etched.
For example, the width of the ink chamber corresponding to 180 dpi is 70.5.
When an ink chamber member having a thickness of .mu.m and a partition member having a thickness of 70.5 .mu.m is to be formed, patterning cannot be performed unless the thickness of the member to be etched is 70 .mu.m or less. This means that the higher the density, the greater the height of the ink chamber cannot be.

Similar defects also apply when a resist is used to form an ink chamber member by a photolithography method. That is, the resist film thickness is 50
When the thickness is μm or more, the resist film can no longer be patterned by the conventional photolithography method. The reason is that the photosensitive resin that is generally used as a resist is designed on the premise that it is used with a film thickness of 50 μm or less.
If used in a resist process with a film thickness exceeding this, problems such as insufficient exposure and insufficient development occur, and fine patterning cannot be performed.

Further, when the resist film is patterned by the usual photolithography method, the ratio of the film thickness of the resist film to the patternable width (aspect ratio;
In the ink chamber member, the aspect ratio is defined as the ratio of the width of the ink chamber to the height of the ink chamber, as will be described below.) Is limited to about 1: 2. . Aspect ratio of resist pattern is 1:
If it exceeds 2, the resist pattern which should be the partition member of the ink chamber may be deformed, the original portion near the substrate may be narrowed to have a so-called "inverse taper" shape, or the upright state cannot be maintained. As a result, a defect with many problems such as being merged with the adjacent pattern occurs.

The defects of the resist pattern as described above are concretely shown in the scanning electron micrograph (500
Will be helpful. The resist pattern shown in the photograph was obtained by the present inventors using a negative type thick film resist THB30 (trade name) manufactured by Japan Synthetic Rubber Co., Ltd., which has sensitivity to ultraviolet rays, and the width of the resist pattern on an aluminum substrate. Is 30 μm, the width (space) between resist patterns is 30 μm, and the height of the resist pattern is 50 μm. The main conditions applied are as follows: resist coating (1000 rpm × 10 seconds) pre-baking (100 ° C., 5 minutes) exposure conditions (100 mW / cm ² , 35 seconds) post-baking (100 ° C., 15 minutes) As is clear from the micrograph of FIG. 5, when the aspect ratio of the resist pattern was about 1.7, the pattern was well removed, and the resist pattern arranged in order was obtained without any defects.

However, when the same resist pattern formation as described above was repeated while gradually increasing the aspect ratio, defects began to be generated near the height of the resist pattern of 60 μm. FIG. 3 illustrates an example in which the resist pattern 32 formed on the aluminum substrate 31 has a reverse taper shape. As shown in the figure, the wall surface of the resist pattern 32 is not formed perpendicularly to the substrate 31, but is narrowed at the base portion 32a. Such an inverse taper pattern is
At the time of exposure, a sufficient amount of light does not reach the base portion 32a of the resist film 32 which is in contact with the substrate 31, so that the exposure amount in the film thickness direction of the resist film 32 becomes uneven. It was done. That is, since the thick film resist used here is a negative resist in which the unexposed portion is dissolved and removed during development, a large amount of the resist film 32 in the vicinity of the base portion 32a of the resist film 32, which is difficult to be exposed, is developed. is there. Such a phenomenon becomes more prominent as the thickness of the resist film is increased. If the resist pattern to be used as the partition member of the ink chamber member has such an inverse tapered shape, the area involved in the adhesion between the substrate 31 and the resist pattern 32 becomes small, and in the worst case, the resist pattern 32 becomes It is peeled off from the substrate 31. Also, even if it is not peeled off,
As the aspect ratio of the resist pattern 32 is increased, the wall of the pattern becomes thinner.
For example, as shown in cross section in FIG.
May fall. When the resist pattern is deformed in this way, it can no longer be used as a partition member of the ink chamber.

FIG. 6 is a scanning electron micrograph (350 times) of an example in which the resist pattern formed on the aluminum substrate has a reverse taper shape and the patterns are partially combined at the top of the pattern. .
The resist pattern of this micrograph is basically formed by the same method as that described above with reference to FIG. 5, but here, for comparison, the width of the resist pattern is 50 μm, Was 50 μm and the height of the pattern was 100 μm, and the resist solution was applied twice for thickening.

From the above results, the resist used here and other commercially available resists
In order to form a resist pattern using these using a conventional method, it is necessary to suppress the aspect ratio to about 1: 2 in order to avoid various defects that occur.

[0023]

SUMMARY OF THE INVENTION The present invention solves many problems of the conventional ink jet head as described above. Therefore, one object of the present invention is to
It can be advantageously used for high-density printing, can be commonly applied to various types such as piezo type, bubble jet type, etc., and high precision type can be easily manufactured and An object is to provide an inkjet head with a high yield.

Another object of the present invention is to provide a method of manufacturing the above-mentioned ink jet head. Still another object of the present invention is to provide a finely-shaped component having a finely-shaped portion composed of fine protrusions or openings, which is useful as an ink chamber of an inkjet head as described above, and a manufacturing method thereof. is there.

These and other objects of the present invention will be readily appreciated from the following detailed description.

[0026]

According to one aspect of the present invention, there are provided a nozzle for ejecting a plurality of inks, an ink chamber for circulating and pressurizing ink communicating with the nozzles, and an ink chamber for the ink chamber. An ink jet head including a pressurizing means for ejecting ink from the nozzle according to a change in volume thereof, wherein the ink chamber is a bottom plate member made of a transparent substrate having a predetermined shape and size, and above the bottom plate member. A bottom wall member made of a non-light-transmissive material formed in a pattern corresponding to the shape of the ink chamber, and a partition member formed in a region above the bottom plate member and not occupied by the bottom wall member. In addition, the partition wall member is formed on the side of the substrate on which the bottom wall member is formed with a partition wall member-forming photosensitive material in the following steps: Coated with a film thickness of the photosensitive material, through the pattern of the bottom wall member, selectively exposed to light to which the photosensitive material is sensitive from the back side of the substrate, thus, The inkjet head is formed by insolubilizing an exposed area of a film of a photosensitive material in a developing solution, and removing an unexposed area of the film of the photosensitive material by development.

According to another aspect of the present invention, a plurality of nozzles for ejecting ink, an ink chamber for communicating and pressurizing ink communicating with the nozzles, and an ink in the ink chamber are changed in volume. In manufacturing an inkjet head including a pressurizing means for discharging from the nozzle, the ink chamber is prepared by the following steps: a transparent substrate having a predetermined shape and dimensions is prepared to form a bottom plate member, and A bottom wall member is formed on the surface of the substrate in a pattern from a non-light-transmissive material, and a partition member-forming photosensitive material is formed on the side of the substrate where the bottom wall member is formed in a predetermined film. A thick coat of the photosensitive material is selectively exposed through the pattern of the bottom wall member to light to which the photosensitive material is sensitive from the backside of the substrate, thus Forming a partition plate member by insolubilizing an exposed region of the film of the photosensitive material in a developing solution and removing an unexposed region of the film of the photosensitive material by development to form a bottom plate member and a bottom plate thereof. A bottom wall member formed in a pattern in conformity with the shape of the ink chamber above the member, and a partition member formed in an area above the bottom plate member and not occupied by the bottom wall member. It is a method of manufacturing a characteristic inkjet head.

Further, the present invention is, on another aspect thereof, a microfabricated component having a microfabricated portion composed of microscopic projections or openings, wherein the microfabricated portion has a predetermined shape and size. A bottom plate member made of a transparent substrate, a bottom wall member made of a non-light-transmitting material formed in a pattern above the bottom plate member in accordance with the shape of the fine shape portion, and above the bottom plate member. And a partition wall member formed in a region not occupied by the bottom wall member, the partition wall member is formed on the side of the substrate on which the bottom wall member is formed, and the partition wall is formed over the entire area. A member-forming photosensitive material is applied in a predetermined film thickness, and a film of the photosensitive material is applied to the photosensitive material from the back side of the substrate through the pattern of the bottom wall member. Selectively exposed to Therefore, the exposed area of the film of the photosensitive material is insolubilized in a developing solution, and the unexposed area of the film of the photosensitive material is removed by development, and the fine features are formed. Has a rectangular cross section that is long in the vertical direction when viewed with respect to the vertical cross section, where the height of the fine features is at least 50.
The micro-shaped component is characterized by having an aspect ratio of at least 1: 3, which is defined as the ratio of the width and height of the space.

Further, in another aspect of the present invention, in manufacturing a finely-shaped component having a finely-shaped portion including a fine protrusion or an opening, the finely-shaped portion is subjected to the following steps. : A transparent substrate having a predetermined shape and dimensions is prepared to form a bottom plate member, and a non-light-transmissive bottom wall member-forming material is applied to the entire surface of the substrate to obtain a bottom plate member. A photosensitive material is further coated on the coating of the bottom wall member forming material, and the formed coating of the photosensitive material is selectively formed by photolithography according to the desired pattern of the bottom wall member. And then using the resulting pattern of the photosensitive material as a mask to selectively remove the coating of the underlying bottom wall member-forming material, thereby forming the bottom wall member in a pattern according to The bottom wall member is shaped A barrier member-forming photosensitive material is applied over the entire area on the formed side with a predetermined film thickness, and a film of the photosensitive material is applied to the back side of the substrate through the pattern of the bottom wall member. Selectively exposing the photosensitive material to light having sensitivity to thereby insolubilize the exposed areas of the coating of the photosensitive material in a developer and to develop the unexposed areas of the coating of the photosensitive material by development. By removing the partition wall member, a bottom plate member, a bottom wall member formed in a pattern above the bottom plate member in accordance with the shape of the fine shape portion, and above the bottom plate member. And the partition wall member formed in a region not occupied by the bottom wall member.

According to the present invention, since the width of the ink chamber can be narrowed, it is possible to print at a higher density than has been conventionally desired. In addition, according to the present invention, since the aspect ratio, which is the ratio of the width and the height of the ink chamber, can be made large, even if the width of the ink chamber is narrow as described above, the ink filled in the ink chamber is The amount is equal to or more than that of the conventional ink chamber, and therefore, it is possible to eject a sufficient amount of ink from the attached nozzle each time printing is performed so as not to impair the printing quality. Further, the inkjet head of the present invention can be similarly advantageously applied to various types of heads.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the best mode for carrying out the present invention will be described. Incidentally, the micro-shaped part of the present invention and its manufacturing method will be described with particular reference to the ink chamber, because a typical example of the micro-shaped part consisting of the fine protrusions or openings provided therein is the ink chamber of the inkjet head. I will do it. Therefore, hereinafter, the term "ink chamber" can be read as "fine shape part".

The ink jet head according to the present invention may be of the piezo type, the bubble jet type, and other known types, if desired, as described below. These inkjet heads have, as a basic structure, nozzles for ejecting a plurality of inks, ink chambers for flowing and pressurizing ink communicating with the nozzles, and inks in the ink chambers for changing the volume thereof. It has a pressurizing means for discharging more.
Here, the pressing means can have various configurations according to the method of the head of the present invention. For example, a piezo-type inkjet head can have a piezoelectric element and related members, such as a diaphragm, as a pressurizing unit. A typical structure of a piezo type inkjet head has already been described with reference to FIG.
Also, the bubble jet type inkjet head is
The pressurizing means can include a heating element and related members, such as electrodes electrically connected to the heating element.

In the ink jet head according to the present invention,
The structure and the shape of the ink chamber contained in it are important. As shown in an enlarged view of a part of FIG. 7, the ink chamber has a bottom plate member 1 made of a transparent substrate having a predetermined shape and size, and a pattern above the bottom plate member 1 according to the shape of the ink chamber. The bottom wall member 2 is made of a non-light-transmissive material, and the partition wall member 5 is formed in a region above the bottom wall member 2 and not occupied by the bottom wall member 2. The partition member 5 has a width w and a height h, and the partition members 5 arranged at equal intervals for forming the ink chamber 12 have an interval (space) of s. is there. Therefore, the "aspect ratio" (defined as the ratio of the width of the ink chamber to the height of the ink chamber) often used in this specification is s: h.

The transparent substrate forming the bottom plate member 1 allows the patterning light to pass through the substrate when the partition member 5 is formed, and when the bottom wall member 2 is formed by etching, the transparent substrate is formed by etching. There is no particular limitation as long as the substrate itself is not damaged or peeled off. Suitable transparent substrate materials include, for example, glass, plastic materials such as polyester resins (PET, etc.), acrylic resins (PMMA, etc.), quartz, and others. These materials may be used in a single layer, or may be used by laminating two or more layers.

A bottom wall member 2 made of a non-light-transmitting material is formed on the bottom plate member 1 so as to be in close contact therewith or, if necessary, with an optional intermediate layer interposed therebetween. It The non-light-transmitting material used here is not particularly limited as long as it can block the transmission of light for patterning when forming the partition member 5 and can ensure a good flow of ink when the head is used. However, preferably, it is a metal material such as chromium, tantalum, nickel, titanium, copper, or aluminum in consideration of easiness of formation and accuracy of the obtained pattern. The bottom wall member 2 may be formed as a single layer from these materials, or may be formed by laminating two or more layers. Also, in some cases,
It may be laminated in combination with an antireflection film or the like. The bottom wall member 2 is preferably formed as thin as possible from the above-mentioned materials, and the normal film thickness is about 0.05 to 1 μm.

The partition wall member 5 used to form the ink chamber 12 together with the bottom wall member 2 is characteristic of the present invention, and is characterized by the following steps: the side of the transparent substrate 1 on which the bottom wall member 2 is formed. Over the entire area, a photosensitive material for forming a partition wall member is applied to a predetermined thickness, and a film of the photosensitive material is applied to the back side of the substrate 1 through the pattern of the non-light transmissive bottom wall member 2. Selectively exposing the photosensitive material to light having sensitivity, thereby insolubilizing the exposed areas of the film of the photosensitive material in a developer, and developing the unexposed areas of the film of the photosensitive material by development. Can be removed, and then formed. This step will be described in more detail in the production of the inkjet head of the present invention described below.

Here, the photosensitive material for forming the partition member is
An appropriate one can be arbitrarily selected and used from a large number of resists generally used in the resist process. The resist normally used here is
It is a negative resist. Suitable resists are preferably
A film having a thickness of at least 50 μm can be formed and patterned. For example, THB-30 (trade name) manufactured by Nippon Synthetic Rubber Co., Ltd. or OMR-83 (trade name manufactured by Tokyo Ohka Co., Ltd.) can be used. ) Can be mentioned. The partition wall member 5 may also be formed from a resist film having a two-layer structure or a multilayer structure of two or more layers for the purpose of utilizing the characteristics of each resist, if necessary.

The ink chamber member shown in FIG. 7 has the simplest configuration. However, in the ink chamber member of the present invention, in order to avoid an inconvenient diffraction phenomenon that may occur, when the partition wall member 5 is arranged on the bottom plate member 1 adjacent to the bottom wall member 2, the bottom wall member 5 is disposed. An intermediate layer having a film thickness thicker than the pattern of the bottom wall member 2 may be interposed between the member 2 and the partition member 5. The intermediate layer is the partition member 5
Can be formed according to any method from a material suitable for forming. Suitable intermediate layer materials are, for example, epoxy resins and other resin materials, SiN ₂ , SiO ₂ , TiO ₂ , and the like. Although the thickness of the intermediate layer can be widely changed, it is usually preferably 5 μm or more. If the thickness of the intermediate layer is less than 5 μm, the problem of diffraction may still not be avoided if the purpose of the intermediate layer is to avoid diffraction phenomena in high aspect ratio applications. The intermediate layer can be formed using a technique such as spray coating, roll coating, brush coating, thermocompression bonding, vapor deposition, and sputtering.

In the ink chamber member according to the present invention, the ink flow path of the ink chamber preferably has a rectangular cross section which is long in the vertical direction when viewed with respect to the vertical cross section. Room height is at least 50μ
m and the aspect ratio (s: h) defined as the ratio of the width of the ink chamber to the height of the ink chamber is at least 1: 3.
Is. In particular, the wall surface of the ink flow path, that is, the wall surface of the partition wall member does not stand upright from the surface of the substrate but has an appreciable inclination. When viewed from the shape of the partition member, the partition member is tapered from the lower side closer to the substrate toward the upper side, which is completely opposite to the reverse tapered partition member of the conventional ink chamber described above with reference to FIG. Is. The shape of such a tapered partition wall member is particularly referred to as a “forward taper” shape in the present specification. The reason why such a forward-tapered partition wall member is formed is, as will be described in detail below, in the patterning method adopted in the present invention, it is lower than the upper portion of the thick film resist used, that is, in the substrate. This is because a closer portion can receive a larger amount of exposure. Since the partition member of the present invention has the forward taper shape in this manner, it can be stably fixed and positioned on the substrate as the bottom plate member, and can be separated from the substrate or fall down during use. Is significantly prevented. As a result, it has become possible to form an ink chamber having a desired shape and size by patterning a resist film having a film thickness of 100 μm or more, which has been considered impossible by conventional techniques.

The formation of the ink chamber having a high aspect ratio of 1: 3 or more was observed by the scanning electron microscope photograph (350 times) of the attached FIG.
Is clear from. The resist pattern in the photograph will be described in detail below by the present inventors using THB30 (trade name), a negative type thick film resist manufactured by Japan Synthetic Rubber Co., Ltd., which has sensitivity to ultraviolet rays. This is the result of patterning on the glass substrate with the width of the resist pattern set to 41 μm, the width (space) between the resist patterns set to 30 μm, and the height of the resist pattern set to 100 μm in accordance with the method of 1. The 30 μm wide chrome pattern used as a mask is not visible in the photograph because it is so thin. The main conditions applied were as follows: resist coating (1000 rpm × 10 seconds, double coating) prebaking (100 ° C., 5 minutes) exposure conditions (10 mW / cm ² , 45 seconds; from glass substrate side) Back exposure) Post bake (100 ° C., 15 minutes) As is clear from the micrograph of FIG. 9, even when the aspect ratio of the resist pattern is about 3.3, the pattern is well removed, and long and narrow resist patterns arranged in order are formed. Obtained without defects. Since the resist pattern has a sufficient height, it is possible to store a large amount of ink in the ink chamber, and thus the printing quality is good.

As the film thickness of the resist used to form the resist pattern having a high aspect ratio as described above increases, the exposure becomes insufficient near the surface of the resist film and the boundary between the exposed portion and the unexposed portion increases. Is easy to be ambiguous. However, in the present invention, since a newer developing solution is supplied to the surface of the resist film after exposure during development, the boundary between the exposed portion and the unexposed portion is not so clear that it is sufficient. Development can be performed to any extent. Therefore, in the case of the present invention, even if the film thickness of the resist film is significantly increased, a resist pattern finer than that achieved by the conventional technique can be formed.

In the production of the ink jet head according to the present invention, the ink chamber has the following series of steps: a transparent substrate having a predetermined shape and dimensions is prepared to form a bottom plate member, and the bottom plate member is formed on the surface of the substrate. A bottom wall member is formed in a pattern from a non-light-transmissive material, and a partition member-forming photosensitive material is applied to a predetermined thickness on the entire side of the substrate on which the bottom wall member is formed. Then, the film of the photosensitive material is selectively exposed to light from the back side of the substrate to which the photosensitive material has sensitivity, through the pattern of the bottom wall member, and thus the film of the photosensitive material. The insoluble region of the photosensitive material is insolubilized in a developing solution, and the unexposed region of the film of the photosensitive material is removed by development to form the partition member. Less than,
Each step will be described. Formation of bottom plate member: A bottom plate member is formed by preparing a transparent substrate having a predetermined shape and dimensions. Suitable transparent substrates that can be used here have been exemplified in the description of the ink chamber configuration above. The surface of the substrate to be used may be subjected to a surface treatment according to a conventional method for the purpose of increasing the adhesion of the bottom wall member and the partition member to it. Forming a patterned bottom wall member: A non-light permeable material is used to pattern the bottom wall member on the surface of the substrate to form the bottom portion of the ink chamber to be formed. As specifically described above, various metal materials can be advantageously used as the non-light-transmitting material for forming the bottom wall member. The bottom wall member may also be formed directly by depositing a selected bottom wall member forming material on a pattern on a substrate, or a selected bottom wall member forming material. After depositing the entire surface of the substrate, only the unnecessary portion may be selectively removed.

The formation of the bottom wall member is particularly preferably carried out according to the latter method, and more preferably the following step: the bottom wall member-forming material is applied over the entire surface of the substrate to obtain the bottom wall member. Further, a photosensitive material is coated on the entire surface of the bottom wall member-forming material, and the formed film of the photosensitive material is selectively formed by photolithography according to the desired pattern of the bottom wall member. Then, using the obtained pattern of the photosensitive material as a mask, the underlying coating film of the bottom wall member-forming material is selectively removed by a photolithography method. Through such a series of steps, the desired patterned bottom wall member can be obtained.

Here, as described above, the film of the bottom wall member forming material as the opaque layer formed first on the substrate is preferably a film made of a metal material, and
The formation can be done by any technique known in the art. Suitable techniques include, but are not limited to, those listed below.

1. PVD method (physical vapor deposition method) Sputtering method, vacuum vapor deposition method, ion plating method, etc. 2. CVD method (chemical vapor deposition method) Thermal CVD method (normal pressure, reduced pressure), plasma CVD method, MO-
CVD method etc. 3. Electroless plating method 4. Coating method Spin coating method, spray coating method, dip coating method, roll coating method, brush coating method, etc.

After forming the coating of the bottom wall member forming material,
A photosensitive material, that is, a resist, used as a mask in the selective removal of the bottom wall member is coated on the upper surface thereof.
The resist used here is not particularly limited, but it is preferable that the desired resist pattern can be formed even when applied with a film thickness of 10 μm or less in order to improve the pattern accuracy. Since it is used for patterning, either a positive type resist or a negative type resist may be used. Suitable resists include, for example, AZ-4620 manufactured by Hoechst, and O manufactured by Tokyo Ohka.
Examples thereof include FPR-8000 and 0MR-83, and Eston DuPont's Liston (all are trade names). The selected resist is applied to a predetermined film thickness by a conventional method, for example, by spin coating, dip coating, spray coating, roll coating, brush coating, etc., and then dried.

Next, the formed resist film is selectively removed by photolithography according to the desired pattern of the bottom wall member. The photolithography method used here can be carried out as usual in a resist process. For example, the exposure of the resist film depends on the type of resist, etc. UV exposure method Contact exposure method, proximity (proximity) exposure method, projection (projection) exposure method, etc.

2. X-ray exposure method 3. An electron beam exposure method or the like can be used. A photomask is used according to the exposure method used, and the mask pattern is also changed according to the type of resist. Development following exposure can also be carried out as is conventional in resist processes.

After the resist pattern is formed, the coating of the underlying bottom wall member forming material is selectively removed using the pattern as a mask. Also for the selective removal of the film, a technique usually used in the manufacturing process of semiconductor devices,
For example, etching, for example: 1. Wet etching method Dip method, shower method, etc.

2. Dry etching method RIE method (reactive ion etching method), ICP method, E
CR method, ion beam etching method, etc. Alternatively, a lift-off method (patterning is performed first, and the bottom wall member forming material is subsequently formed into a film) can be used. The desired bottom wall member is obtained in a pattern. Formation of partition wall member: After the bottom wall member is formed in a desired pattern, the partition wall member for separating adjacent ink chambers is formed as the last step of forming the ink chambers.

First, a photosensitive material capable of forming a partition wall member is applied to the side of the substrate on which the bottom wall member has been formed in the previous step to a predetermined thickness. Although the photosensitive material used here, that is, the resist, is not particularly limited, it is possible to increase the film thickness to at least 50 μm in order to make the partition member thicker and increase the aspect ratio of the ink chamber. Is preferred. Further, this resist is required to be dissolved and removed in a non-exposed area with a developing solution, and is therefore a so-called "negative resist".
Further, in order to increase the film thickness of this negative resist, two or more resist films may be laminated. Examples of a suitable negative resist include THB-30 manufactured by Nippon Synthetic Rubber Co., Ltd. and 0MR-83 manufactured by Tokyo Ohka Co., Ltd. (both are trade names). The selected resist is applied to a predetermined film thickness by a conventional method, for example, by spin coating, dip coating, spray coating, roll coating, brush coating, etc., and then dried. The thickness of the resulting resist film for forming partition members is preferably at least 50 μm, usually 50 to 200 μm or more.

Next, the formed resist film is selectively removed by photolithography to form a partition member. The photolithography method used here may be the same as that used in the previous bottom wall member forming step. For example, the exposure method may be an ultraviolet exposure method or an X-ray exposure method depending on the photosensitivity of the resist used. Such as the law. In this exposure step, it is important to perform the exposure from the back side of the transparent substrate. That is, the formed resist film is selectively exposed from the back side of the substrate without using a special photomask, but using the patterned bottom wall member opaque to light as a mask. The exposure from the back surface of such a transparent substrate is generally called "back exposure". As a result of exposure using light to which the resist is sensitive as an exposure source, the exposed area of the resist film, that is, the area where the transmission of light was not blocked by the mask of the bottom wall member, is insolubilized in the developing solution.

After the exposure is completed, the unexposed region (soluble region) of the resist film is dissolved and removed with a developing solution. This developing step can be carried out as is normally done in the resist process. For example, the developing solution to be used and the developing time can be appropriately selected depending on the kind of the resist. As an example, when the resist used is THB-30 (described above), when developing the resist film after exposure, a developer exclusively for THB-30 commercially available from Nippon Synthetic Rubber Co., Ltd. Can be used. As a result of development, the desired partition member is obtained. The sectional shape of the obtained partition member is a forward tapered shape, as described above.

According to the method of the present invention, the partition wall member having the elongated forward taper shape is formed as described above, so that the aspect ratio of the ink chamber can be set to 1: 3 or more. By the way, according to the knowledge of the present inventors, if the height of the partition member is increased to increase the aspect ratio, for example, the aspect ratio becomes 1: 5 or more (in other words, in the ink chamber). If the height is 150 μm or more when the width is 30 μm), “cutting” (or swelling of the member) may occur at the base of the partition member due to the diffraction phenomenon of light during exposure. Although the notch of the partition member does not adversely affect the self-supporting property of the partition member itself, it reduces the volume of the ink chamber, and thus it is desirable to prevent it. This diffraction phenomenon will be described with reference to FIG. 15 (for convenience of description, a state in which the partition member is already formed is shown).

In the step of forming the partition member as described above, when the resist film 5 having the partition member forming property is selectively back-exposed through the bottom wall member 2 as a mask, if the back exposure is large, the exposure amount is large. Then, the diffraction of the light indicated by the arrow in the drawing occurs at the edge portion of the bottom wall member 2. Part of the exposure also goes around to the back side of the bottom wall member 2, and that part is also cured. Therefore, when the resist film 5 after exposure is developed, as shown in the drawing, a notch 5a of the member occurs at the base of the obtained partition member 5. Resist film 5
If the film thickness is large, it is usually necessary to perform a large amount of exposure accordingly, and therefore it is possible to achieve a thick resist film and prevent the above-mentioned undesired light diffraction. desirable.

In a preferred embodiment of the method of the present invention, after the bottom wall member is formed in a pattern and before the partition wall member-forming resist is further applied, the bottom wall member already formed is formed. By covering the pattern of the wall member, that is, with a film thickness thicker than the pattern of the bottom wall member,
The method is further characterized by further including a step of forming an intermediate layer made of a light-transmittable material used for exposing the resist for forming the partition wall member.

Since the intermediate layer is arranged on the pattern of the bottom wall member in this way, even if diffraction of light still occurs, the diffraction is limited to the inside of the non-reactive intermediate layer, and the partition wall forming resist is formed. It does not even reach the membrane. Therefore, it is possible to obtain the partition member having no defect such as a notch in the base portion. The material used for forming the intermediate layer is not particularly limited as long as it can transmit the light used for exposing the resist for forming the partition member. Suitable interlayer materials include, but are not limited to, those listed below, such as epoxy resins and other plastic materials, SiN ₂ , SiO ₂ , TiO _{2, and the} like. Further, in some cases, the above-mentioned resist capable of forming a partition member may be used as an intermediate layer material. These intermediate layer materials can be applied in a desired film thickness using conventional techniques, for example, spray coating, roll coating, brush coating, thermocompression bonding, vapor deposition, sputtering and the like. A suitable thickness of the intermediate layer is usually 5 μm or more,
It is preferably 5 to 50 μm. If the film thickness is less than 5 μm, the diffraction of light cannot be absorbed in the intermediate layer. On the other hand, if it exceeds 50 μm, the self-supporting property of the partition member on the intermediate layer may be adversely affected.

The ink chamber member manufactured as described above may be used as it is for manufacturing an ink jet head. Otherwise, if necessary, the manufactured ink chamber member may be used as a mold for electroforming. Alternatively, the ink chamber member made of a metal material may be used by the subsequent electroforming process. The metal ink chamber member formed by the electroforming process is particularly advantageous in that a partition wall having high rigidity can be formed and therefore the partition wall width can be narrowed.

The electroforming process can be carried out using conventional techniques. For example, the surface of an ink chamber member having a partition member made of a resist film serving as an electroforming mold is coated with an electroforming electrode film over the entire surface. Suitable electrode film materials include conductive metal materials such as gold, copper, nickel,
Examples thereof include silver, platinum, tungsten and the like. In addition, it is preferable to add a metal such as chromium in order to enhance the adhesion to the ink chamber member that is the base. A vapor deposition method, a sputtering method, an electroless plating method, or the like can be used for coating the electrode film. After forming the electrode film, electroforming treatment is performed. Electroformed materials that can be used advantageously here are:
For example, it is a metal such as nickel or copper or an alloy thereof. For example, the electroforming process using nickel can be carried out under the following conditions. Composition of electroforming bath: water 5 L (liter) nickel sulfamate 1650 g nickel chloride 150 g boric acid 225 g sodium lauryl sulfate 5 g bath temperature: 60 ° C. ± 1 ° C. current density: 50 mA / cm ² stirring speed: 1 L / min As above When the electroforming treatment using the bath is performed and then the mold release is performed, an ink chamber member made of nickel having a thin electrode film on its surface is obtained. The shape and dimensions of the ink chamber member correspond to those of the ink chamber member used as the mold.

The ink jet head according to the present invention can be advantageously applied to the ink jet heads of the piezo type, bubble jet type, and other types, as already described. For example, a piezo type inkjet head can be manufactured by disposing a pressurizing means including a piezoelectric element or the like on the ceiling portion of the ink chamber member formed as described above. For example, when the ink chamber member takes a form as shown in the attached FIG. 8 produced in the following Example 1, that is, the ink chamber 12 has the bottom plate member 1, the bottom wall member 2, and the partition wall member 5. When it is constructed, it is incorporated into the ink jet head shown in FIG. 1, for example, with its ink chamber facing the lower surface, so that a desired piezo system ink jet head can be obtained.

The ink jet head of the bubble jet system uses a heating element and an electrode electrically connected thereto as a pressurizing means, and the pressurizing means is used during the formation of the ink chamber member described above. It can be manufactured by forming on. Incorporation of the pressurizing means onto the bottom wall member can be carried out in various ways by applying the technique usually used for manufacturing a bubble jet head.

For example, the ink chamber member of the bubble jet type ink jet head as shown in FIG. 14 can be manufactured as follows. First, after forming the bottom wall member 2 in a predetermined stripe pattern on the surface of the bottom plate member 1 made of a transparent substrate, the entire surface thereof is covered with the heat resistant insulating layer 6. The material forming the insulating layer may be an insulating material commonly used in the field of semiconductor devices and the like, for example, SiN, SiO _2, etc., and these materials are formed by a general method such as a sputtering method or a vapor deposition method. be able to. Insulation layer 6
The film thickness of is not particularly limited, but is generally about 0.05 to 1 μm.

After forming the insulating layer 5, the heating element 7 is striped.
Shape, but preferably with a narrower width than the bottom wall member 2.
To wear. The heating element material used here is, for example, Ta₂N,
 TaN _X, Nichrome-based materials. These heating element materials
Material over the entire surface by, for example, sputtering or vapor deposition.
After that, it is selectively removed by etching or the like. Illustrated
The heating element 7 is formed with such a putter. The heating element 7
Although the film thickness of is not particularly limited, it is generally about
It is 0.05 to 1 μm.

Subsequently, the electrode 8 for supplying a current to the heating element 7 is formed. In the illustrated example, the electrodes 8 are formed so as to straddle both ends of the heating element 7. Although the electrode material used here is not particularly limited as long as it has appropriate conductivity, for example, SnO ₂ ,
In ₂ O ₃ and the like. After depositing these electrode materials on the entire surface by, for example, a sputtering method or a vapor deposition method, they are selectively removed by etching or the like. The electrodes 8 are formed in a pattern as shown. Although the thickness of the electrode 8 is not particularly limited, it is generally about 0.05 to 1 μm.

After the heating element 7 and the electrode 8 are formed, the partition member 5 is formed according to the technique described above. In this way, an ink chamber member particularly suitable for the bubble jet system is obtained. Subsequently, a flat plate (not shown) is placed on the upper surface of the ink chamber 12 to cover the opening. In this way, a desired bubble jet type inkjet head can be obtained. If a nozzle plate is placed instead of the flat plate placed on the ink chamber, ink can be ejected perpendicularly to the heating element.

[0066]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to the accompanying drawings, regarding typical embodiments thereof. It should be understood that the present invention is not limited to these examples. Example 1 Formation of Ink Chamber Member As shown in FIG. 10A, a transparent glass substrate 1 having a thickness of 400 μm was prepared. The glass substrate prepared here serves as a bottom plate member in the intended ink chamber member and is transparent with respect to ultraviolet rays because it transmits ultraviolet rays for exposure when forming the partition member.

Then, as shown in FIG. 10B, a chromium thin film 2 having a film thickness of 0.15 μm and a width of 30 μm is formed on the substrate 1.
Was applied in a striped manner to a predetermined portion of. The chromium thin film 2 serves as a bottom wall member of the ink chamber.
It was formed as shown in order from (A) to (D) of FIG. On the transparent glass substrate 1 shown in FIG. 11A, a chromium thin film 2 having a thickness of 0.15 μm was entirely deposited as shown in FIG. 11B. This chrome thin film 2
For film formation, a sputtering device manufactured by Tokki Co., Ltd. was used, RF power was 450 W, argon (Ar) gas pressure was 0.
Film formation was performed at 01 torr for 5 minutes.

Then, on the formed chromium thin film 2,
AZ4620, a positive resist for thin films manufactured by Hoechst
(Trade name) was spin-coated at 4000 rpm for 30 seconds. A uniform film of AZ resist was obtained with a film thickness of 6 μm.
This resist film was heated in an electric furnace at 90 ° C. for 20 minutes to be pre-baked, then exposed using a mask having a predetermined pattern, and further developed and patterned. As shown in FIG. 11C, a resist pattern 3 was formed on the chromium thin film 2.

To further explain the patterning of the resist film, the apparatus used for exposing the resist film was an ultraviolet exposure apparatus manufactured by Union Optical Co., Ltd., and the exposure amount was 100 mJ / cm ² . The mask used is L
It is a type of mask in which a pattern is drawn on a glass substrate with a chromium film, which is generally used in the field of manufacturing SI devices. On this mask, a plane pattern of the ink chamber of the ink chamber member to be produced is drawn. Since the pattern has an interval of the obtained ink chambers of 71 μm, the line portion (chrome film portion; Transmission was blocked) and the space portion (opening portion; light transmission possible) was 41 μm. The interval of the ink chambers of 71 μm means that 360 ink chambers can be arranged per inch, in other words, printing can be performed at a high density of 360 dpi. In addition, the development of the resist film after exposure is
A dedicated developer was used for the used resist, AZ4620, and the developing time was about 1 minute. After the development, the obtained resist pattern was rinsed with pure water to wash away the residual developing solution, and further post-baked by heating at 120 ° C. for 20 minutes in an electric furnace. A cured resist pattern was obtained.

After forming the resist pattern 3 as shown in FIG. 11C, the underlying chromium thin film 2 was patterned by the wet etching method. In this example,
Since the object of etching is a chromium thin film, pure water: cerium ammonium nitrate: 60% perchloric acid = 800 ml: 1
6 g: 16 ml of an etching solution for chromium was used. As a result of the etching, the pattern of the resist pattern 3 was transferred to the chrome thin film 2 as it was, and as shown in FIG. 11D, the chrome pattern 2 which served as the bottom wall member of the ink chamber member was obtained. The dimensional error between the resist pattern 3 and the chrome pattern 2 was very small and was on the order of submicrons.

After forming the chrome pattern, FIG.
As shown in FIG. 3, a thick resist film 5 was coated on the entire surface of the transparent substrate 1 on the side of the chrome pattern 2. The resist used in this step is a negative type thick film resist, THB-30 (trade name), which is manufactured by Japan Synthetic Rubber Co., Ltd. and is UV sensitive.
This resist was spin-coated on the substrate at 1000 rpm for 10 seconds. A resist film having a film thickness of about 50 μm was obtained. After spin coating, the substrate was heated on a hot plate at 100 ° C. for 5 minutes. By this post-baking, the solvent in the resist film was evaporated and the thermal curing was completed. By the way, in the above process, only a resist film having a film thickness of about 50 μm can be obtained, and the ink chamber having a high aspect ratio intended in this example cannot be formed. In this example, therefore, the above-described resist film forming step was repeated once again. As a result of applying the resist twice, a thick resist film (film thickness = about 100 μm) was obtained.

Subsequently, the obtained thick film resist film was patterned to obtain a partition member. First, as shown in FIG. 10D, the resist film 5 formed on the transparent substrate 1 was irradiated with ultraviolet rays (see arrow) from the opposite side of the substrate 1. The apparatus used for exposing the resist film is an ultraviolet exposure apparatus manufactured by Union Optical Co., Ltd., and the exposure amount is 300.
It was mJ / cm ² . The irradiated ultraviolet rays were transmitted through the inside of the substrate 1 as they were, but were blocked from being transmitted by the chromium pattern 2 and were reflected or absorbed. Of the ultraviolet rays that passed through the substrate 1, the ultraviolet rays that were not blocked by the chromium pattern 2 were incident on the resist film 5 as they were. That is, the chrome pattern 2 acted as a mask in this ultraviolet exposure process.
As a result, the resist film 5 was pattern-exposed with a desired pattern, that is, with a desired planar shape pattern of the ink chamber. The exposed area of the resist film 5 was therefore made insoluble in the developing solution in the subsequent developing step.

After pattern exposure of the resist film, the used resist, THB-30, was subjected to immersion development of the exposed resist film using a dedicated developer. The temperature of the developing solution was 35 ° C., and the developing time was 3 minutes. As a result of the development, only the unexposed area of the resist film which was not made insoluble in the developing solution in the previous exposure step was dissolved and removed, and the resist pattern 5 as shown in FIG. 10E was obtained. In the figure, the transparent substrate 1
Corresponds to the bottom plate member of the ink chamber member of the present invention, the chrome pattern 2 corresponds to the bottom wall member, and the resist pattern 5 corresponds to the partition member. Further, the space formed by being surrounded by these three members is the ink chamber 12.

FIG. 8 is a perspective view showing a main part of the ink chamber member manufactured as described above. In this figure, in order to make the shape easy to understand, the dimensions of the respective members are enlarged and shown. In the ink chamber member 11 shown,
On a bottom plate member 1 having a thickness of 400 μm, a chromium bottom wall member 2 having a film thickness of 0.15 μm and patterned in a plane shape of an ink chamber, and a resist partition wall member 5 having a film thickness of 100 μm.
And are formed. The width of the ink chamber 12 was 30 μm at the bottom of the ink chamber (boundary with the bottom plate member 1), and the width of the partition member 5 partitioning the ink chambers 12 was 41 μm at the bottom. As a result, the width-height ratio of the ink chamber is 1 :.
It became possible to make it 3 or more. It should be noted that a plurality of ink chamber members 11 manufactured in this example (not shown in the drawing,
Ink chambers 12 (only four are shown) are one chamber at the rear, and further communicate with the ink supply port 12a.

Looking at the sectional shape of the partition wall member 5 of the ink chamber member 11, the width of the partition wall member 5 forming the ink chamber 12 is as follows.
It becomes narrower as it goes away from the bottom plate member 1 (that is, the ink chamber 12 becomes wider as it goes away from the member 1), and has a forward tapered shape. The inclination angle of the partition wall member 5 was about 6 ° when measured. Patterning and forming the partition member 5 with such a cross-sectional shape is one of the most characteristic features of the patterning method adopted in the present invention, that is, the ink chamber forming method. Example 2 Formation of Ink Chamber Member The procedure described in Example 1 above was repeated. However, in the present invention, in order to form the partition member, the same thick film resist was applied three times under the same application conditions, and the film thickness was set to 150 μm. Further, in this example, since the film thickness of the resist film was increased, the exposure amount at the time of pattern exposure was also increased to 450 mJ / cm ² . A high aspect ratio ink chamber member having an ink chamber width to height ratio of 1: 5 was obtained.

The principal portion of the obtained ink chamber member is shown in cross section in FIG. Bottom wall member 2 and partition wall member 5
The ink chamber 12 formed by the above has a width of 30 μm and a height of 150 μm. As can be seen from these results, in this example, it was possible to form an ink chamber having a high aspect ratio of 1: 5. In addition, the partition member 5 of the ink chamber member
Similarly to the case of Example 1, the portion contacting the bottom plate member 1 had a width of 41 μm and an inclination angle of about 6 °.
Due to the above, an ink chamber with a height of 150 μm can be used at 360 dp.
It was possible to form the ink chamber members arranged at a distance of i (ink chamber spacing 71 μm). Example 3 Formation of Electroformed Ink Chamber Member The procedure described in Example 1 above was repeated. However, in the present invention, since the obtained ink chamber member is used as an electroforming mold for forming the electroformed ink chamber member, a partition member (thick film resist) for separating the ink chamber from the adjacent ink chamber is used. (Consisting of)). That is, the pattern of the mask used when forming the chromium pattern as the bottom wall member was reversed. As a result, the obtained ink chamber member had a pattern opposite to that of the ink chamber member obtained in Example 1, and the portion which became the ink chamber in Example 1 became the partition member and the partition member in Example 1 became the partition member. Each part turned into an ink chamber. A cross section of the obtained ink chamber member (electroforming mold) is shown in FIG. In this figure, in order to avoid complication of the drawing, only the bottom plate member 1 and the partition wall member 5 are shown, and the bottom wall member is omitted.

Next, for electroforming, FIG.
As shown in, the electroforming electrode film 21 was formed on the surface of the formed ink chamber member. First the chrome film is 0.05
Then, a gold (Au) film having a thickness of 0.2 μm was formed by a vapor deposition method. The chromium film formed here first is for increasing the adhesion of the Au film to the base.

Subsequently, nickel is further deposited on the Au film by about 0.3 mm by an electroforming method which is generally widely used.
Was grown to a film thickness of. For this nickel film formation, a treatment bath having the following composition was used: water 5 L nickel sulfamate 1650 g nickel chloride 150 g boric acid 225 g sodium lauryl sulfate 5 g. The temperature of the treatment bath was 60 ° C. ± 1 ° C., the current density was 50 mA / cm ² , and the stirring speed of the bath was 1 L / min. By this electroforming method, as shown in FIG. 12C, the electroformed member 22 made of nickel was formed.

After nickel electroforming, FIG.
The whole of what was shown in (4) was immersed in a stripping solution exclusively for thick film resists which was subjected to ultrasonic waves. The separating member 5 was peeled from the electroformed member 22, further dissolved in the peeling liquid, and disappeared. When the separating member 5 was melted, the bottom plate base material 1 supporting the separating member 5 was also separated from the electroformed member 22. As a result, as shown in FIG. 12D, an electroformed ink chamber member including the electroformed member 22 and the electrode film 21 coated on the surface thereof was obtained. The electroformed ink chamber member thus obtained is shown in FIG.
As can be seen by comparing with the electroforming mold, the pattern is the reverse of the original mold. Therefore, the recess of the electroformed ink chamber member can also be used as the ink chamber. Example 4 Formation of Bubble Jet Inkjet Head Using a method similar to that described in Example 1 above, a thickness of 40
A striped chromium pattern having a width of 30 μm and a film thickness of 0.15 μm was formed on a transparent glass substrate of 0 μm.

Next, an insulating film made of a silicon oxide film (SiO ₂ ) having a thickness of 0.2 is formed on the substrate having the chromium pattern.
It was formed with a size of μm. To form this silicon oxide film, a silicon thin film was first grown and then thermally oxidized. Further, a heating element made of tantalum nitride (TaN) is formed on the chrome pattern through the previously formed insulating film so as to have a film thickness of 0.1 μm, and patterned with a width of 20 μm narrower than the width of the chrome pattern. did. An electrode having a width of 20 μm and a film thickness of 0.2 μm made of a conductive material (SnO ₂ ) was formed on the formed stripe-shaped heating element so as to traverse both ends thereof. Since SnO ₂ used as the electrode material here is transparent, it does not hinder the progress of light that passes through the substrate and is incident on the thick film resist during the subsequent selective exposure for forming the partition member.

After a series of processes as described above, FIG.
A laminated structure as shown in (A) of was obtained. That is, on a transparent substrate 1, a striped chromium pattern 2, an SiO ₂ insulating film 6 deposited on the entire surface, a striped TaN heating element 7 having a width slightly narrower than the chromium pattern 2, and a heating element 7 are formed. SnO ₂ electrode 8 formed across both ends of
Are sequentially formed. Here, the formed combination of the heating element 7 and the electrode 8 constitutes the pressurizing means of the bubble jet type inkjet head to be manufactured in this example.

After forming the pressing means as described above,
A partition member was formed in the same manner as that described in Example 1 above. First, as shown in FIG. 13 (B), a thick film resist is entirely coated on the side of the heating element 7 and the electrode 8 of the transparent substrate 1, and the resist film 5 formed on the substrate 1 is coated. The substrate 1 was irradiated with ultraviolet rays (see arrow) from the opposite side.

After pattern exposure of the resist film, the exposed resist film was immersion developed. As a result of the development, only the unexposed area of the resist film was dissolved and removed, and a resist pattern 5 as shown in FIG. 13C was obtained. FIG. 14 is a perspective view showing a main part of the ink chamber member manufactured as described above. In this figure, in order to make the shape easy to understand, the dimensions of the respective members are enlarged and shown. In the figure, the transparent substrate 1 corresponds to the bottom plate member of the ink chamber member of the present invention, the chromium pattern 2 and the insulating film 6 thereon correspond to the bottom wall member, and the resist pattern 5 corresponds to the partition member. Further, the space formed by being surrounded by these three members is the ink chamber 12. When the upper part of the ink chamber 12 is covered with a flat plate (not shown), the ink chamber 12 is completely closed and can be used in the head portion. If you use a nozzle plate instead of this flat plate,
In the resulting inkjet head, it is possible to eject ink in a direction perpendicular to the heating element. Example 5 Formation of Ink Chamber Member The procedure described in Example 1 above was repeated. However, in this example, the thick film resist was applied four times, and the thickness of the obtained resist pattern was set to 200 μm. Also, in order to avoid the problem of light diffraction at the base of the resist pattern that occurs in the case of such a thick film, after forming the chrome pattern and before forming the resist pattern on it, the entire surface of the transparent substrate For the intermediate layer.

First, as shown in FIG. 16A, a film thickness of 0.15 μm is formed on a transparent glass substrate 1 having a thickness of 400 μm.
A chromium thin film 2 having m and a width of 30 μm was applied in a stripe shape. Then, for forming an intermediate layer, a thick film resist having a film thickness of 20 μm was spin-coated on a transparent substrate having a chromium pattern. The thick film resist used here is the same as the thick film resist used when forming the subsequent partition member,
This was THB-30 (trade name), which is a UV-sensitive negative type thick film resist manufactured by Japan Synthetic Rubber Co., Ltd. The spin coating conditions were a rotation speed of 2000 rpm and a coating time of 10 seconds. As shown in FIG. 16B, the intermediate layer 4 was formed on the entire surface of the transparent substrate 1. Subsequently, in order to cure the formed intermediate layer 4, the entire surface was exposed to ultraviolet rays as indicated by the arrow in FIG. The apparatus used for the exposure of this intermediate layer is an ultraviolet exposure apparatus manufactured by Union Optical Co., Ltd., and the exposure amount is a high level of 1200 mJ / cm ² so that the intermediate layer does not cause an undesired reaction in the subsequent step. It was

After the formation of the intermediate layer, the thick film resist, THB-30, was applied onto the substrate and patterned according to the method described in Example 1 above. First, as shown in FIG. 16 (C), a thick film resist was entirely coated on the intermediate layer 4 side of the transparent substrate 1. In this resist coating process, 100
Spin coating (film thickness of about 50 μm) at 0 rpm for 10 seconds, followed by prebaking at 100 ° C. for 5 minutes was repeated 4 times. As a result of applying the resist four times, a thick (thickness = about 200 μm) resist film 5 was obtained.

Subsequently, the obtained thick film resist film was patterned to obtain a partition member. FIG. 16C
The resist film 5 formed on the transparent substrate 1 as shown in FIG.
The substrate was irradiated with ultraviolet rays (see arrow) from the opposite side. This ultraviolet irradiation was performed according to the method described in Example 1, except that the exposure amount was changed to 1200 mJ / cm ² in order to correspond to the increased film thickness of the resist film 5.

After pattern exposure of the resist film, the exposed resist film was immersion developed according to the method described in Example 1 above. In this example, the temperature of the developing solution was still 35 ° C., but the developing time was extended to 6 minutes. As a result of development,
Only the unexposed area of the resist film was dissolved and removed, and a resist pattern 5 as shown in FIG. 16D was obtained. Although the height of this resist pattern is as high as 200 μm (the pattern is low in the figure for the sake of drawing), the “cut” defect found in the base of the conventional resist pattern is generated. I was able to avoid it. In the figure, the transparent substrate 1 corresponds to the bottom plate member of the ink chamber member of the present invention, the chrome pattern 2 and the intermediate layer 4 covering it correspond to the bottom wall member, and the resist pattern 5 to the partition member. Equivalent to. Further, the space formed by being surrounded by these three members is the ink chamber 12.

[0088]

As can be understood from the above description, according to the present invention, the width of the ink chamber, which is a finely-shaped portion, can be narrowed, so that it is possible to achieve higher-density recording than has been conventionally desired. . In addition, according to the present invention, since the aspect ratio, which is the ratio of the width and the height of the ink chamber, can be made large, even if the width of the ink chamber is narrow as described above, the ink filled in the ink chamber is The amount is equal to or more than that of the conventional ink chamber, and therefore, it is possible to eject a sufficient amount of ink from the attached nozzle each time printing is performed so as not to impair the printing quality. Further, in the present invention, not only the ink chamber can be formed easily and accurately, but also inconveniences such as deformation can be avoided, and the yield is good. Furthermore, the ink jet head of the present invention is not limited to the piezoelectric type, and can be similarly advantageously applied to various types of heads.

[Brief description of drawings]

FIG. 1 is a development view showing a configuration of a conventionally used piezoelectric inkjet head.

2A to 2C are cross-sectional views sequentially showing formation of an ink chamber using a photolithography method which is generally performed.

FIG. 3 is a cross-sectional view showing an example of a defect that occurs in forming an ink chamber using a photolithography method.

FIG. 4 is a cross-sectional view showing another example of a defect that occurs in forming an ink chamber using a photolithography method.

FIG. 5 is a scanning micrograph (500 times) of a fine pattern on a substrate showing an example of an ink chamber formed by using a photolithography method.

FIG. 6 is a scanning micrograph (350 ×) of a fine pattern on a substrate, showing another example of an ink chamber formed using a photolithography method.

FIG. 7 is a sectional view showing a preferred example of an ink chamber formed according to the present invention.

FIG. 8 is a perspective view showing a preferred example of an ink chamber member equipped with an ink chamber formed according to the present invention.

FIG. 9 is a scanning micrograph (350 times) of a fine pattern on a substrate showing an example of an ink chamber formed according to the present invention.

FIG. 10 is a cross-sectional view showing the formation of an ink chamber according to the present invention step by step.

11A to 11C are cross-sectional views sequentially showing a method that can be advantageously used for forming the bottom wall member in FIG. 10B.

12A to 12C are cross-sectional views sequentially showing steps of forming a metal ink chamber member by electroforming using the ink chamber member formed according to the present invention as an electroforming mold.

13A to 13C are cross-sectional views sequentially showing formation of the ink chamber member shown in FIG.

FIG. 14 is a perspective view showing another preferable example of the ink chamber member equipped with the ink chamber formed according to the present invention.

FIG. 15 is a cross-sectional view illustrating the diffraction of light in the vicinity of the bottom of the ink chamber, which is recognized in the formation of the ink chamber member according to the present invention.

16A to 16C are cross-sectional views sequentially showing a method of forming an ink chamber member according to the present invention, in which the diffraction of light described with reference to FIG. 15 is excluded.

[Explanation of symbols]

1 ... Bottom plate member 2 ... Bottom wall member 5 ... Partition member 11 ... Ink chamber member 12 ... Ink chamber (fine shape part)

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-305142 (JP, A) JP-A-1-225559 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/045 B41J 2/055 B41J 2/16

Claims (7)

(57) [Claims] 1. A bottom plate member comprising a micro-shaped part including a micro-projection or an opening, wherein the micro-shaped part is a transparent substrate having a predetermined shape and dimensions, and A bottom wall member made of a non-light-transmitting material formed in a pattern above the bottom plate member in conformity with the shape of the fine shape portion, and formed in a region above the bottom plate member and not occupied by the bottom wall member The partition wall member is formed into a predetermined film on the entire surface of the side wall of the substrate on which the bottom wall member is formed. The coating of the photosensitive material is applied in a thickness, and selectively exposed to light to which the photosensitive material has sensitivity from the back side of the substrate through the pattern of the bottom wall member. The exposed area of the film of the conductive material Insolubilizing in a developer and removing the unexposed areas of the coating of the photosensitive material by development, and the fine features are formed according to
When viewed with respect to a vertical cross section, it has a rectangular cross section that is long in the vertical direction, where the height of the fine features is at least 50 μm and is defined as the ratio of the width of the space to the height. A finely shaped component having an aspect ratio of at least 1: 3. 2. The intermediate layer having a film thickness thicker than the pattern of the bottom wall member is interposed between the bottom wall member and the partition member on the bottom wall member. Fine shape parts. 3. The micro-shaped component is formed of a metal material by an electroforming method, and the partition member formed in the previous step is used as a mold for the electroforming method when forming the fine shaped component. The micro-shaped component according to claim 1 or 2, characterized in that 4. In manufacturing a micro-shaped component having a micro-shaped portion composed of micro-projections or openings, the micro-shaped portion is prepared by the following steps: preparing a transparent substrate having a predetermined shape and size. To form a bottom plate member, coat the entire surface of the substrate with a non-light-transmissive bottom wall member-forming material, and further sensitize the film on the obtained bottom wall member-forming material. Of the photosensitive material, and the formed film of the photosensitive material is selectively removed by photolithography according to the desired pattern of the bottom wall member, and then the resulting pattern of the photosensitive material is obtained. As a mask, by selectively removing the coating of the underlying bottom wall member-forming material, to form a bottom wall member in a pattern in accordance with the film on the side of the substrate on which the bottom wall member is formed. Bulkhead over the entire area A member-forming photosensitive material is applied in a predetermined film thickness, and a film of the photosensitive material is applied through the pattern of the bottom wall member to the light from which the photosensitive material from the back side of the substrate has sensitivity. Selectively exposing, to thereby insolubilize the exposed area of the film of the photosensitive material in a developer, and remove the unexposed area of the film of the photosensitive material by development to form the partition member, According to the above, a bottom plate member, a bottom wall member formed above the bottom plate member in a pattern according to the shape of the fine shape portion, and an area above the bottom plate member and not occupied by the bottom wall member. A method of manufacturing a finely-shaped component, which is characterized in that it is formed with the formed partition wall member. 5. A thicker film than the pattern of the bottom wall member after forming the bottom wall member in a pattern and before applying a photosensitive material capable of forming a partition wall member thereon. The manufacturing method according to claim 4, further comprising a step of forming an intermediate layer. 6. The fine feature is formed so as to have a rectangular cross section that is long in the vertical direction when viewed with respect to a vertical cross section, wherein the height of the fine feature is at least 50 μm and The manufacturing method according to claim 4 or 5, wherein an aspect ratio defined as a ratio of a space width to a height is at least 1: 3. 7. The method according to claim 7, further comprising the step of using the partition member formed in the previous step as a mold for an electroforming method and forming a finely-shaped portion made of a metal material by a subsequent electroforming step. The manufacturing method according to any one of claims 4 to 6.