JPH111000A - Manufacture of nozzle plate, ink jet head, nozzle plate, and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nozzle plate used for a face eject type ink jet head for ensuring a discharge amount of necessary ink droplet even by enhancing a density in an ink jet head by reducing fluid resistance of an orifice. SOLUTION: Etching resistant films 502 are formed at least on both surfaces of a single crystal silicon substrate 500 of plane direction (110), and a first opening 510 for forming a recess for an orifice is formed at the film. Then, a predetermined unpenetrating hole 512 is formed at a predetermined part of the first opening, the silicon substrate formed with the unpenetrating hole is wet etched to form a recess 110 for the orifice.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a nozzle plate used in an ink jet head, an ink jet head and an ink jet recording apparatus.

[0002]

2. Description of the Related Art Ink jet heads used in an ink jet recording apparatus include an edge eject type in which ink droplets are ejected from nozzle holes formed in an end portion of an ink jet head substrate, and an ink jet head formed on the surface of an ink jet head substrate. There is a face eject type in which ink droplets are ejected from nozzle holes. Of these, the face eject type ink jet head can arrange a large number of nozzle holes in structure, so it is possible to increase the density compared to the edge eject type ink jet head,
More suitable for high resolution and high speed printing.

As a nozzle plate used in the face-eject type ink jet head, a nozzle plate obtained by subjecting a stainless steel substrate to electrical discharge machining has been put into practical use. In order to further increase the density, a single-crystal silicon substrate is subjected to plasma etching. Have been studied.

[0004] This face-eject type ink jet head is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-50601 (8).
Column 41, line 9 to column 5, line 5) and JP-A-6-71882 (column 10, line 7 to column 11, line 2).

On the other hand, among face-eject type ink-jet heads using a single-crystal silicon substrate for a nozzle plate, anisotropic wet etching using an alkali can be performed. It is also possible to form a recess for use. Here, the orifice is an ink flow path that connects a plurality of ink chambers for pressurizing the ink and a common ink reservoir that supplies the ink to the ink chamber.

[0006]

However, the recess for the orifice formed by subjecting the single-crystal silicon substrate to the anisotropic wet etching process using alkali as described above has a low etching rate in the anisotropic etching step. Since it is affected by the anisotropy, it has a triangular cross-sectional shape as shown in FIG. 1 and inevitably becomes shallow. Therefore, as the density of the ink-jet head is increased, the volume decreases sharply, whereby the fluid resistance increases sharply,
There is a problem that the ejection amount of the ink droplet is reduced and it is difficult to obtain a necessary ejection amount.

On the other hand, a method of forming a nozzle plate by performing a plasma etching process on a single crystal silicon substrate is as follows.
In order to form a nozzle hole having a wall surface perpendicular to the surface of the single crystal silicon substrate with good reproducibility, frequent cleaning and maintenance of a vacuum pump and the like for removing deposits in a vacuum chamber of a plasma etching apparatus are performed. Although it is necessary to always maintain the plasma etching apparatus in a constant state, since it takes a long time to perform the plasma etching processing, it is actually difficult to completely perform this,
As a result, there is a problem that it is difficult to ensure the verticality of the nozzle hole. In addition, the method of performing a plasma etching process on a single crystal silicon substrate to form a nozzle plate has a problem that it is an obstacle to mass production of a nozzle plate because a plasma etching apparatus is expensive and has low processing capability. there were.

On the other hand, when the nozzle holes are formed by plasma etching and the orifice recesses are formed by anisotropic wet etching using alkali, 1) When the nozzle holes are formed first In order to prevent the nozzle from being etched excessively in the subsequent anisotropic wet etching process using an alkali, it is necessary to form a defect-free etching-resistant film at the nozzle hole portion. Has a portion that is nearly perpendicular to the substrate surface, so it is difficult to reliably form a defect-free etching-resistant film at the edge, so the nozzle hole shape is deformed (even if the defect-free resistance is high). Even if an etching film can be formed, it is very difficult to perform high-precision patterning for forming an orifice recess on the etching-resistant film.) 2) When processing the orifice recess first, it is difficult to reliably form a defect-free etching resistant film at the edge of the deep orifice recess. There is a problem of deformation (even if a defect-free etching resistant film can be formed, it is very difficult to perform high-precision patterning for forming a nozzle hole on the etching resistant film).

Therefore, the present invention solves the above-mentioned problems, and aims at 1) reducing the fluid resistance of the orifice so that the ink required even if the density of the ink jet head is increased. It is an object of the present invention to provide a nozzle plate for use in a face-eject type ink-jet head capable of ensuring a droplet discharge amount, and 2) to efficiently use a nozzle plate for a face-eject type ink-jet head in which the perpendicularity of nozzle holes is ensured. Providing a well-manufacturing method, and 3) solving all of the above-mentioned problems caused by forming the nozzle hole and the orifice recess in different processing steps by forming the nozzle hole and the orifice recess in the same processing step. Nose used in a face-ejection type inkjet head It is to provide a method of manufacturing a plate.

Another object of the present invention is to provide an excellent face-eject type ink jet head having the nozzle plate manufactured as described above, and to provide an excellent ink jet recording apparatus having such an ink jet head. is there.

[0011]

According to a first aspect of the present invention, there is provided a method of manufacturing a nozzle plate, comprising forming an etching-resistant coating on at least both surfaces of a (110) oriented single crystal silicon substrate.
And a second step of forming a first opening for forming an orifice recess in the etching-resistant coating.
A third step of forming a predetermined non-through hole in a predetermined portion of the first opening, and a fourth step of forming a recess for an orifice by performing wet etching of the single crystal silicon substrate having the non-through hole formed therein. And in this order.

Therefore, in the method according to the first aspect of the present invention, the presence of the predetermined non-through hole can overcome the adverse effect of the anisotropic etching rate in the anisotropic etching step. It is possible to form a concave portion for use. For this reason, it is possible to reduce the fluid resistance of the orifice, and it is possible to alleviate a sudden decrease in the volume of the orifice as the density of the ink jet head is increased, and to secure a necessary discharge amount of ink droplets. Can be.

[0013] According to a second aspect of the present invention, there is provided a method of manufacturing a nozzle plate.
A first step of forming an etching resistant film on at least both surfaces of a (110) plane oriented single crystal silicon substrate, and a second step of forming a second opening for forming a nozzle hole in the etching resistant film. A third step of forming a predetermined non-through hole in a predetermined portion of the second opening, and a third step of forming a nozzle hole by performing wet etching of the single crystal silicon substrate having the non-through hole formed therein. And step 4 in this order.

Therefore, in the method according to the second aspect of the present invention, the presence of the predetermined non-through holes can overcome the adverse effect due to the anisotropy of the etching rate in the anisotropic etching step. Deep vertical holes can be made using processing. For this reason, it is not necessary to use the plasma etching process, and it is possible to efficiently manufacture a nozzle plate in which the perpendicularity of the nozzle holes is secured.

According to a third aspect of the present invention, there is provided a method for manufacturing a nozzle plate.
A first step of forming an anti-etching film on at least both sides of a (110) plane oriented single crystal silicon substrate, and a second step of forming a first opening for forming an orifice recess and a second hole for forming a nozzle hole; A second step of forming an opening in the etching-resistant coating, a third step of forming a predetermined non-through hole in a predetermined portion of the first and second openings, and a step of forming the non-through hole. And a fourth step of forming a recess for an orifice and a nozzle hole by performing wet etching of the single crystal silicon substrate in this order.

For this reason, the method of claim 3 has the effect of the method of claim 1 and the effect of the method of claim 2, and at the same time, forms the nozzle hole and the recess for the orifice in different processing steps. It is possible to solve the problem, that is, the problem that the shape of the nozzle hole or the recess for the orifice is deformed.

According to a fourth aspect of the present invention, there is provided a method for manufacturing a nozzle plate.
The method for manufacturing a nozzle plate according to any one of claims 1 to 3, wherein 1) a first opening and / or a second opening and a third surface for forming a nozzle surface side recess. The opening is formed in the etching-resistant coating and the second
Is carried out.

[0018] Therefore, the method of claim 4 can increase the thickness of the nozzle plate to some extent due to the presence of the recess on the nozzle surface side, in addition to the effects of the methods of claims 1 to 3. This has the effect that the strength of the steel can be increased.

[0019] The method for manufacturing a nozzle plate according to claim 5 is as follows.
In the method for manufacturing a nozzle plate according to any one of claims 1 to 4, wet etching is performed between the second step and the third step.

Therefore, the method according to claim 5 has an effect that the processing time of the non-through hole in the third step can be shortened since the processing portion of the predetermined non-through hole is processed in advance by a predetermined amount. .

According to a sixth aspect of the present invention, there is provided a method for manufacturing a nozzle plate.
In the method of manufacturing a nozzle plate according to any one of claims 1 to 5, the third step is performed by using a laser processing method.

Therefore, the method of claim 6 has an effect that the predetermined non-through hole can be formed at a high speed.

According to a seventh aspect of the present invention, there is provided a method for manufacturing a nozzle plate.
The method for manufacturing a nozzle plate according to claim 6,
The third step is characterized in that the third step is performed such that the depth of the non-through hole is larger than the length of the nozzle hole.

For this reason, the method of claim 7 does not require strict accuracy with respect to the depth accuracy, since it is sufficient if a certain amount or more can be formed in the processing of the non-through hole. In other words, there is an effect that a processing method with poor processing depth accuracy, in particular, a laser processing method can be used.

[0025] The method of manufacturing a nozzle plate according to claim 8 is as follows.
The method for manufacturing a nozzle plate according to claim 6,
The third step is performed so that the sum of the thickness of the crystal fusion portion formed around the non-through hole and the depth of the non-through hole is larger than the length of the nozzle hole.

According to the method of claim 8, since it is only necessary to perform processing of a certain amount or more including the thickness of the crystal melting portion generated in the laser processing, the processing amount in the laser processing can be reduced. Having.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a nozzle plate.
The method of manufacturing a nozzle plate according to any one of claims 1 to 5, wherein the third step is performed by using a plasma etching method.

Therefore, the method according to the ninth aspect has an effect that a predetermined non-through hole can be formed at a high speed. There are various difficulties in processing the nozzle hole itself with high precision (high verticality) using the plasma etching method as described above, but it is not necessary to form the non-through hole with high precision. Therefore, processing can be performed under processing conditions of a high etch rate (in a plasma etching processing method, it is difficult to achieve both high etch rate and high precision).

According to a tenth aspect of the present invention, in the method of the ninth aspect, the third step is performed so that the depth of the non-through hole is larger than the length of the nozzle hole. It is characterized by doing.

For this reason, the method of claim 10 does not require strict accuracy in depth accuracy, since it is only necessary to process a certain amount or more in the processing of the non-through hole. That is, there is an effect that processing can be performed even under processing conditions in which the processing depth accuracy is not good. There are various difficulties in performing high-precision processing with respect to depth using the plasma etching processing method, but since it is not necessary to perform non-through-hole formation with high precision,
This has an effect that a margin of processing conditions can be widened.

According to an eleventh aspect of the present invention, there is provided a method of manufacturing a nozzle plate according to any one of the first to tenth aspects, wherein the (110) single crystal silicon substrate is replaced with the (110) plane oriented single crystal silicon substrate. A SOI substrate of a single-crystal silicon substrate having a plane orientation is used.

Therefore, the method of claim 11 facilitates making the nozzle length equal to the thickness of the active layer of the SOI substrate, that is, has the effect of making the nozzle length highly accurate. .

According to a twelfth aspect of the present invention, there is provided a method for manufacturing a nozzle plate, comprising: a first step of forming an anti-etching film on at least both surfaces of a single crystal silicon substrate having a (110) plane orientation; and a step of forming a first nozzle hole. A second step of forming a depressed portion for forming a fourth opening and a second nozzle hole in the etching-resistant coating; and a second step of forming a predetermined non-through hole in a predetermined portion of the fourth opening. Step 3 and wet etching of the single crystal silicon substrate on which the non-through-holes are formed are carried out so that 1) the first nozzle hole and 2) the back surface side of the nozzle plate so as to communicate with the first nozzle hole. And a fourth step of forming a second nozzle hole having a larger sectional area than the first nozzle hole in this order.

Therefore, the method of claim 12 has an effect that a two-stage nozzle can be formed. Improving the ink flow rate near the nozzles by using a two-stage nozzle in which a first nozzle hole from which ink is ejected and a second nozzle hole having a larger cross-sectional area than the first nozzle hole are used. In other words, there is an effect that the bubble discharging property can be improved.

According to a thirteenth aspect of the present invention, there is provided a method of manufacturing a nozzle plate according to the twelfth aspect, wherein the fourth opening and the recess are formed, and the nozzle surface side recess is formed. The method is characterized in that the opening of No. 3 is formed in an etching-resistant film and the second step is performed.

Therefore, the method of claim 13 is based on claim 1
In addition to the effects of the second method, the presence of the concave portion on the nozzle surface side makes it possible to increase the thickness of the nozzle plate to some extent, thereby increasing the strength of the nozzle plate.

According to a fourteenth aspect of the present invention, there is provided an ink jet head having a nozzle plate manufactured by the method for manufacturing a nozzle plate according to any one of the first to thirteenth aspects.

Therefore, in the ink jet head according to the present invention, by using the nozzle plate having the deep orifice concave portion, it is possible to alleviate the rapid decrease in the volume of the orifice as the density of the ink jet head is increased. This has the effect that a required amount of ink droplets can be ejected. Further, the ink jet head according to claim 14 is manufactured efficiently, and uses a nozzle plate having nozzle holes or orifices with vertical and / or high length accuracy and / or high shape accuracy, thereby providing inexpensive and high quality printing. Is possible.

A nozzle plate according to a fifteenth aspect is a nozzle plate having a first nozzle hole and a second nozzle hole communicating with each other in a longitudinal direction, wherein the cross-sectional area of the first nozzle hole is equal to that of the second nozzle hole. The second nozzle hole is smaller than the first nozzle hole and is formed on the back side of the nozzle plate with respect to the first nozzle hole.

Therefore, the nozzle plate according to the fifteenth aspect has an effect that the ink flow velocity near the nozzles is large, that is, the bubble discharging property is excellent.

The nozzle plate according to the sixteenth aspect is the first aspect.
5. The nozzle plate according to item 5, wherein the nozzle plate is a nozzle plate manufactured using a (110) -oriented single-crystal silicon substrate, and the first and second nozzle holes are formed on the single-crystal silicon substrate. It comprises a plurality of planes including four (111) crystal planes perpendicular to the surface.

Therefore, the nozzle plate of claim 16 has an effect that the perpendicularity of the first and second nozzle holes is good in addition to the effect of the nozzle plate of claim 15.

According to a seventeenth aspect of the present invention, there is provided an ink jet head including the nozzle plate according to the fifteenth or sixteenth aspect.

Therefore, the ink jet head according to the seventeenth aspect has the effects of high air bubble discharge and high print quality.

An ink jet recording apparatus according to claim 18 is:
An ink jet head according to claim 14 or 17 is provided.

Therefore, the ink jet recording apparatus according to claim 18 has the effect that the ink jet head according to claim 14 or 17 has the same effect.

The ink jet recording apparatus referred to herein is an apparatus having an ink jet head and capable of recording information on a medium such as paper, a plastic sheet, a resin, etc., and includes all printers, faxes, and copies. It is a thing.

[0048]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments.

Embodiment 1 FIG. 3 is a sectional view of an ink jet head 400 according to Embodiment 1. The ink jet head 400 according to the first embodiment has the nozzle plate 1
00, cavity plate 200 and electrode plate 300
Are joined together. The nozzle plate 100 has a nozzle hole 120 and an orifice recess 110. The orifice recess 110 becomes an orifice 112 when joined, and connects the ink cavity 212 and the ink reservoir 222.
The cavity plate 200 is formed with an ink cavity concave portion 210, an ink reservoir concave portion 220, and a vibration plate 230. The concave portion 210 for the ink cavity and the concave portion 220 for the ink reservoir form an ink cavity 212 and an ink reservoir 222 in a joined state. The ink cavity 212 is processed perpendicular to the surface of the cavity plate 200, the ink reservoir 222 supplies ink to the ink cavity 212, and the vibration plate 230 presses the ink. The electrode plate 300 is provided with an electrode 310 for electrostatically attracting the vibration plate 230 and thereby pressing the ink in the ink cavity 212. The ink is supplied from the ink supply pipe 50 to the ink reservoir 222 and finally becomes the ink droplet 10 as the nozzle hole 120.
Is discharged from. The nozzle plate 100 and the cavity plate 200 are both made of a single crystal silicon substrate having a (110) plane orientation.

FIG. 4 is a perspective view of the nozzle plate 100 according to the first embodiment. In each nozzle hole 120, two orifice recesses 110 are formed corresponding to each other, but depending on design conditions, the number of orifice recesses may be one, or may be three or more.

FIG. 5 shows the nozzle plate 100 of the first embodiment.
FIG. 3 is a manufacturing process diagram of a first step (a) of forming an etching-resistant coating on at least both surfaces of a (110) single-crystal silicon substrate, a first opening for forming a recess for an orifice, and A second step (b) of forming a second opening for forming a nozzle hole in the etching resistant coating, and a second step of forming a predetermined non-through hole in a predetermined portion of the first and second openings. Step (c) of Step 3 and a fourth step (d to e) of forming a recess for an orifice and a nozzle hole by performing wet etching of the single crystal silicon substrate having the non-through hole formed therein. ing.

(First Step: FIG. 5A) A 400 μm-thick (110) plane single-crystal silicon substrate 500 serving as the nozzle plate 100 is placed at 1100 ° C. for 4 hours in an atmosphere containing water vapor. A heat treatment is performed to form a silicon thermal oxide film 502 having a thickness of 1 μm as an etching resistant film on both surfaces of the single crystal silicon substrate.

(Second Step: FIG. 5B) Thermal Oxide Film 50
2 is subjected to photoetching, and the orifice recess 11
0, a nozzle hole 120, and an opening 51 for forming a nozzle surface side concave portion 130 for penetrating the nozzle hole.
0, 520 and 530 are formed. The shape of the opening 510 is a parallelogram having a width of 20 μm and a length of 500 μm, and the shape of the opening 520 has a side of 30 μm and an inner angle of 7 μm.
The sides of the parallelogram having a length of 500 μm and a set of parallel sides of the rhombus are aligned parallel to the <112> direction of the single crystal silicon substrate (FIG. 6). ).

(Third Step: FIG. 5C) Predetermined non-through holes 512 and 522 are formed in predetermined portions of the first opening 510 and the second opening 520. The formation of the non-through hole is Y
This was performed using an AG laser. Parameters such as the power and the number of pulses of the YAG laser were set to appropriate values in order to form a vertical deep hole. From the inkjet head standard,
The target value of the unpenetrated hole depth is determined. In the first embodiment, the target value of the depth of the orifice recess is 80 μm and the target value of the nozzle length is 30 μm according to the standard of the inkjet head.
m. Normally when laser processing single crystal silicon,
A crystal fusion part is formed around the processed part. Since the crystal fusion part has lost crystallinity, when performing wet anisotropic etching on the laser-processed part, the etching proceeds to the part having crystallinity and automatically stops with an etch stop. Become. That is, as the depth of the non-through hole 522, it is only necessary to process the depth by subtracting the thickness of the crystal fusion part from the target value of the actual processing depth. In addition, the depth of the non-through hole 522 (including the thickness of the crystal fusion part)
Should be 30 μm or more, which is the target value of the length of the nozzle hole, but it is preferable that the depth is slightly deeper in consideration of the variation in depth.
In the first embodiment, as a result, the non-through hole 512 formed in a predetermined portion of the first opening 510 has a diameter of about 15 μm and a depth of about 75 μm, and is formed in a predetermined portion of the second opening 520. The unpenetrated hole 522 had a diameter of about 18 μm and a depth of about 35 μm (the thickness of the crystal fusion portion is about 5 μm, 0). Further, in the first embodiment, two non-through holes are formed in each of the openings 510, respectively, in order to shorten the anisotropic wet etching time in the subsequent fourth step. Or, even when three or more non-through holes are formed, by adjusting the depth of the non-through holes, the shape of the orifice concave portion finally obtained becomes the same.

(Fourth Step: FIGS. 5D to 5E) Next, anisotropic wet etching using an alkali was performed. Example 1
Used an aqueous solution of potassium hydroxide. Usually (110)
When anisotropic wet etching is performed on a single-crystal silicon substrate having a plane orientation using an alkali, an opening of an etching mask (a silicon thermal oxide film in Example 1) forms an angle of 35 degrees with a plane perpendicular to the substrate surface. Plane (both are (111) planes of single crystal silicon) appear, and etching stops when two 35 degree (111) planes emerging from both ends of the opening intersect at the bottom of the recess formed by etching. However, in the first embodiment, since the non-penetrating hole is formed by the laser processing, the non-penetrating hole 5 is formed.
No (111) plane at 35 degrees to the substrate surface appears up to the point where the bottoms of 12 and 522 intersect with the (111) plane, and there are four (111) planes perpendicular to the substrate surface. Accurate nozzle holes 120 and orifice recesses 110 can be formed (see FIG. 4). FIG. 5D shows the progress of anisotropic wet etching using an alkali. Etching is progressing also in the etching portion 532 from the opening 530. In FIG. 5D, the etched portion 532 is depicted as having a vertical surface despite the absence of laser drilling.
Actually, the area of the etched portion 532 is much larger than the area of the nozzle hole 120. Therefore, by devising the shape of the opening 530, a cross-sectional shape almost as shown in FIG. 5D can be formed. When the etching is further performed, the etching does not further proceed in the etching portion 524 serving as the nozzle hole and the etching portion 514 serving as the orifice recess as described above, but the etching proceeds in the etching portion 532 in accordance with the etching time. Eventually, the etching portion 524 that becomes the nozzle hole penetrates and the nozzle hole 120
Is formed. If the nozzle hole 120 is further etched after the penetration, the length of the nozzle hole 120 becomes shorter in accordance with the etching time. Therefore, the etching is stopped when the nozzle hole 120 has a desired length (FIG. 5E).

(Subsequent Steps) Then, the thermal oxide film 502 as an etching mask is removed with a hydrofluoric acid-based etchant (FIG. 5F), and the silicon thermal oxide film 504 is newly formed to impart ink resistance. Forming the nozzle plate 100
Is completed (FIG. 5 (g)).

As described above, in the conventional method, although the orifice has a high precision, only a shape uniquely determined with respect to the etching opening can be obtained. That is, the orifice has no flexibility in the fluid resistance value. In this embodiment, the orifice can be formed vertically and with good shape accuracy with respect to the nozzle plate surface, and the depth can be arbitrarily determined by laser processing. It was able to correspond to the design value of the fluid resistance of the orifice in the specification. Thereby, in the narrow orifice of the high-density inkjet head, the optimum fluid resistance value can be obtained,
That is, it was possible to provide an ink jet head capable of high printing quality and high speed printing. Further, as described above, the diameter of the nozzle hole formed by the conventional method (plasma etching) has a slight variation. However, in this embodiment, the nozzle hole diameter is determined by the pattern formed by the photo etching. It has become possible to form a large number of nozzle holes with high reproducibility and high accuracy at low cost. This allows
It has been possible to stabilize the print quality and reduce the cost of the high-density inkjet head and the inkjet recording apparatus using the inkjet head. In addition, the boring process at a predetermined position in FIG. 5C can be performed by plasma etching. In this case, the processing depths of the non-through holes 512 and 522 are substantially the same, but the depth of the orifice concave portion 110 is reduced by performing plasma etching in accordance with the predetermined processing depth of the deeper non-through hole 512. Both the length and the length of the nozzle hole 120 can be formed as desired. Non-through hole 5 to be a nozzle hole
Although the depth of the nozzle hole 22 becomes larger than the target value of the nozzle hole length at the stage of the step (c) in FIG. 5, the length of the nozzle hole 120 is finally defined by the etching depth of the etching portion 532. Therefore, there is no problem. Although there are various types of plasma etching, it is preferable to use a method called trench etching, which can perform vertical deep hole processing. (Embodiment 2) In Embodiment 2, anisotropic wet etching using an alkali is performed after the second step in Embodiment 1 of the present invention, so that the unpenetrated holes in the subsequent third step are removed. The processing amount is reduced, and the throughput in this step is improved.

FIG. 7 is a manufacturing process diagram of the nozzle plate 100a used in the ink jet head according to the second embodiment, which is basically the same as the first embodiment, and only different portions will be described in detail.

7A and 7B, a silicon thermal oxide film 702 is formed on a single crystal silicon substrate 700 in the same manner as in the first embodiment of the present invention. Recess 110a, nozzle hole 120
a, and openings 710, 720, 73 for forming the nozzle surface side concave portion 130a for penetrating the nozzle hole.
0 is formed. Next, in the step of FIG. 7C, the wet anisotropic etching of the silicon substrate 700 is performed. In the etching part, the etching automatically ends when two (111) planes 703 appearing at an angle of 35 degrees with respect to the surface of the silicon substrate 700 intersect. Next, in the step of FIG. 7D, a non-through hole is formed by a laser processing method as in the first embodiment of the present invention, but the processing amount at that time is smaller than that of the first embodiment. For good, there is an effect that processing time is shortened.

(Embodiment 3) FIG. 8 shows a nozzle plate 100b used for an ink jet head in Embodiment 3.
It is a manufacturing process diagram, and the manufacturing process will be described in detail below. In this embodiment, a SOI substrate 800 of a (110) plane single crystal silicon substrate is used instead of the (110) plane single crystal silicon substrate 500 as a substrate serving as the nozzle plate 100b. The active layer 802 has a thickness of 15 μm, the dielectric layer (SiO ₂ ) 804 has a thickness of 0.05 μm, the support 806 has a thickness of 400 μm, and both the active layer 802 and the support 806 have (11
0) It is single crystal silicon having a plane orientation. FIG.
Since the processing conditions in (g) are exactly the same as in the case of the first embodiment, the description is omitted. Si by YAG laser
Since the power required for processing the dielectric layer 804 can be ignored in the hole drilling, the processing depth is the same as that in the first embodiment of the present invention within the range of variation. With the use of the SOI substrate, the etching in the etching portion 832 from the opening 830 is automatically stopped when the dielectric layer 804 appears. The thickness of the dielectric layer 804 is 0.05 μm
However, the etching must be terminated at an appropriate point because it disappears in the anisotropic wet etching for a long time (about 10 minutes), but the etching is stopped even in consideration of the etching variation in the same batch. Has a tolerance of about ± 5 minutes, so the yield in this step is 10
0%.

The nozzle plate 100 obtained in the present embodiment
b, the length of the nozzle hole 120b is the same as the thickness of the active layer 802, that is, the etching depth variation (typically ± 5 μm
Irrespective of the degree, the active layer thickness variation achieved in the SOI substrate manufacturing process (± 1 μm depending on the accuracy of the polishing process)
m), the nozzle hole length accuracy is secured.
An ink jet head with higher printing quality could be provided.

In the third embodiment, both the orifice and the nozzle hole are formed on the nozzle plate. However, only the orifice or only the nozzle hole is formed on the nozzle plate by the method of the present invention, and the orifice or the nozzle hole is formed. Does not depart from the gist of the present invention when formed on the nozzle plate or another substrate by another method.

(Embodiment 4) FIG. 9 is a sectional view of an ink jet head 400c in Embodiment 4. The ink jet head 400c according to the fourth embodiment has a structure in which the nozzle plate 100c, the cavity plate 200c, and the electrode plate 300c are joined. Ink ejection principle of ink jet head 400c, cavity plate 200c and electrode plate 300c
Is the same as that of the first embodiment of the present invention, and the description is omitted.

FIG. 10 is a perspective view of a nozzle plate 100c according to the fourth embodiment. The nozzle holes of the nozzle plate 100c are composed of a first nozzle 120c1 and a second nozzle 120c2 having different cross-sectional areas in the ink ejection direction.
It has a stepped shape and is closer to the recording medium (first nozzle 1
20c1) has a small cross-sectional area. With such a shape, the ink flow velocity near the nozzle hole increases,
Although it is possible to improve the air bubble discharging property, portions other than the nozzle holes have basically the same structure as that of the first embodiment of the present invention, and a description thereof will be omitted.

FIG. 11 shows the nozzle plate 10 of the fourth embodiment.
FIG. 10C is a manufacturing process diagram of FIG. 0C, showing a first step (a) of forming an etching-resistant coating on at least both surfaces of a single crystal silicon substrate having a (110) plane orientation, and a first opening for forming a recess for an orifice; , The fourth for forming the first nozzle
A second step (b-d) of forming an opening, a recess for forming a second nozzle, and a third opening for forming a recess on the nozzle surface side in the etching resistant film;
And a third step (e) of forming a predetermined non-through hole in a predetermined portion of the fourth opening, and performing a wet etching of the single crystal silicon substrate having the non-through hole to form a recess for an orifice and The fourth step of forming the nozzle hole (f to
h).

(First Step: FIG. 11A) A single-crystal silicon substrate 1100 having a thickness of 400 μm and having a (110) plane orientation and serving as a nozzle plate 100c was heated at 1100 ° C. for 4 hours in an atmosphere containing water vapor. After heat treatment, 1 μm as an etching resistant film is formed on both surfaces of this single crystal silicon substrate.
A silicon thermal oxide film 1102 having a thickness is formed.

(Second Step: FIGS. 11B to 11D) The thermal oxide film 1102 is subjected to photoetching to form the orifice recess 110c, the first nozzle 120c1, and the nozzle surface side recess 130c for penetrating the nozzle hole. Openings 1110, 1120c1 and 1130 for forming, and a recess 1120c2 for forming the second nozzle 120c2 are formed. The shape and dimensions of the opening 1110 and the opening 1130 are the same as those in the first embodiment of the present invention. Recess 11
The shape of 20c2 is a rhombus with a side of 50 μm, which is similar to the shape of the opening 1120c1, and the shape of the opening 1120c1 is
It is arranged concentrically with respect to c1. Also, the depression 1120
The thickness of the silicon thermal oxide film of c2 is 0.7 μm.

(Third Step: FIG. 11E) Predetermined non-through holes 1112 and 112 are formed in predetermined portions of the first opening 1110 and the second opening 1120c1 by a YAG laser.
Form 2 The processing of the non-penetrating hole 1112 was performed under the same conditions as in the case of the non-penetrating hole 512 of the first embodiment.
In the processing of step 122, parameters such as the power and the number of pulses of the YAG laser are set to appropriate values.
μm and a depth of about 80 μm.

(Fourth Step: FIGS. 11F to 11H) Next, anisotropic wet etching using alkali was performed. In Example 4, an aqueous solution of potassium hydroxide was used as in Example 1, but anisotropic wet etching was performed twice. In the first anisotropic wet etching, the portion 1124 to be the first nozzle and the orifice recess 110c are formed by etching for a predetermined time (step of FIG. 11F). At this point, the silicon thermal oxide film in the recessed portion 1120c2 is etched by the potassium hydroxide aqueous solution,
The film thickness, which was initially 0.7 μm, has become thinner. Next, the remaining silicon thermal oxide film in the recess 1120c2 is entirely removed with a hydrofluoric acid-based etchant (step of FIG. 11 (g)). Next, the second anisotropic wet etching is performed to form the second nozzle 120c2. As for the etching time, the portion 1124 serving as the first nozzle penetrates by etching the etching portion 1132 serving as the nozzle surface side recess 130c, the length of the first nozzle 120c1 is 30 μm, and the depth of the second nozzle 120c2 is 50 μm. Is adjusted as follows.

(Subsequent Steps) Next, the thermal oxide film 1102 as an etching mask is removed with a hydrofluoric acid-based etchant, and a silicon thermal oxide film 1104 is formed again to impart ink resistance. It is completed (FIG. 11 (i)).

The drilling of a predetermined portion in FIG. 11E can be performed by plasma etching. Although there are various types of plasma etching, it is preferable to use a method called trench etching, which can perform vertical deep hole processing. In the nozzle plate 100c obtained in the fourth embodiment, the nozzle holes have a two-stage shape including the first nozzle 120c1 and the second nozzle 120c2 having different cross-sectional areas in the ink ejection direction.
Since the ink flow rate in the vicinity of the nozzle hole was increased and it was possible to improve the bubble discharging property, it was possible to provide an ink jet head of high print quality by using this nozzle plate.

In the present embodiment, both the orifice recess and the nozzle hole are formed on the nozzle plate. However, only the orifice recess or only the nozzle hole is formed on the nozzle plate by the method of the present invention. The case where the orifice recess or the nozzle hole is formed on the nozzle plate or another substrate by another method does not depart from the gist of the present invention.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an etching principle in a conventional technique.

FIG. 2 is an explanatory diagram of an etching principle in the present invention.

FIG. 3 is a cross-sectional view of the inkjet head according to the first embodiment.

FIG. 4 is a perspective view of a nozzle plate according to the first embodiment.

FIG. 5 is a sectional view of the manufacturing process of the nozzle plate in the first embodiment.

FIG. 6 is an explanatory diagram of a patterning direction of an opening.

FIG. 7 is a cross-sectional view illustrating a manufacturing process of the nozzle plate according to the second embodiment.

FIG. 8 is a cross-sectional view illustrating a manufacturing process of the nozzle plate according to the third embodiment.

FIG. 9 is a sectional view of an inkjet head according to a fourth embodiment.

FIG. 10 is a perspective view of a nozzle plate according to a fourth embodiment.

FIG. 11 is a cross-sectional view illustrating a manufacturing process of the nozzle plate in the fourth embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 nozzle plate 110 recess for orifice 112 orifice 120 nozzle hole 130 recess on nozzle surface side 200 cavity plate 212 ink cavity 222 ink reservoir 230 diaphragm 300 electrode plate 310 electrode 400 inkjet head 512, 522 non-through hole

Claims (18)

[Claims] 1. A first step of forming an etching resistant film on at least both surfaces of a (110) plane oriented single crystal silicon substrate, and a first opening for forming a recess for an orifice is formed on the etching resistant film. A second step of forming, and a third step of forming a predetermined non-through hole at a predetermined portion of the first opening.
And a fourth step of forming a recess for an orifice by performing wet etching of the single crystal silicon substrate having the non-through hole formed therein in this order. . 2. A first step of forming an etching resistant film on at least both surfaces of a (110) plane oriented single crystal silicon substrate, and a second opening for forming a nozzle hole is formed in the etching resistant film. A second step of forming a predetermined non-through hole in a predetermined portion of the second opening, and a wet etching of the single crystal silicon substrate having the non-through hole formed therein. Fourth forming hole
And a step of producing the nozzle plate in this order. 3. A first step of forming an etching-resistant coating on at least both surfaces of a (110) plane oriented single crystal silicon substrate, and forming a first opening and a nozzle hole for forming a recess for an orifice. Forming a second opening in the etching resistant film,
A third step of forming a predetermined non-through hole in a predetermined portion of the opening, and a step of forming an orifice recess and a nozzle hole by performing wet etching of the single crystal silicon substrate having the non-through hole formed therein. 4. A method for manufacturing a nozzle plate, comprising the steps of: 4. The method for manufacturing a nozzle plate according to claim 1, wherein: 1) forming the first opening and / or the second opening; and 2) forming the recess on the nozzle surface side. A method for manufacturing a nozzle plate, comprising: forming a third opening to be formed in an etching-resistant film; and performing a second step. 5. The method of manufacturing a nozzle plate according to claim 1, wherein wet etching is performed between the second step and the third step. Method. 6. The method of manufacturing a nozzle plate according to claim 1, wherein the third step is performed by using a laser processing method. 7. The method of manufacturing a nozzle plate according to claim 6, wherein the third step is performed such that the depth of the non-through hole is larger than the length of the nozzle hole. Production method. 8. The method of manufacturing a nozzle plate according to claim 6, wherein the sum of the thickness of the crystal melting portion formed around the non-through hole and the depth of the non-through hole is larger than the length of the nozzle hole. The method of manufacturing a nozzle plate, wherein the third step is performed as described above. 9. The method of manufacturing a nozzle plate according to claim 1, wherein the third step is performed by using a plasma etching method. 10. The method of manufacturing a nozzle plate according to claim 9, wherein the third step is performed such that the depth of the non-through hole is larger than the length of the nozzle hole. Production method. 11. The method of manufacturing a nozzle plate according to claim 1, wherein the SOI of the (110) plane single crystal silicon substrate is replaced with the (110) plane single crystal silicon substrate. A method for manufacturing a nozzle plate, comprising using a substrate. 12. A first method for forming an etching resistant film on at least both surfaces of a (110) plane oriented single crystal silicon substrate.
Forming a fourth opening for forming a first nozzle hole and a recess for forming a second nozzle hole in the etching resistant film; A third step of forming a predetermined non-through hole in a predetermined portion of the portion;
By performing wet etching of the single crystal silicon substrate on which the non-through holes are formed, 1) a first nozzle hole and 2)
Forming a second nozzle hole formed on the back surface side of the nozzle plate so as to communicate with the first nozzle hole and having a larger cross-sectional area than the first nozzle hole in this order. Characteristic method of manufacturing nozzle plate. 13. The method of manufacturing a nozzle plate according to claim 12, wherein the fourth opening and the recess are formed, and the third opening for forming the nozzle surface side recess is formed of an etching resistant film. A method for manufacturing a nozzle plate, comprising forming and performing a second step. 14. An ink jet head having a nozzle plate manufactured by the method for manufacturing a nozzle plate according to claim 1. 15. A nozzle plate having a first nozzle hole and a second nozzle hole communicating in the longitudinal direction, wherein the cross-sectional area of the first nozzle hole is smaller than that of the second nozzle hole, and A nozzle plate wherein a second nozzle hole is formed on the back side of the nozzle plate with respect to the first nozzle hole. 16. The nozzle plate according to claim 15, wherein the nozzle plate is a nozzle plate manufactured using a single crystal silicon substrate having a (110) plane orientation, and the first and second nozzle holes are formed. A nozzle plate comprising a plurality of planes including four (111) crystal planes perpendicular to the surface of the single crystal silicon substrate. 17. An ink jet head comprising the nozzle plate according to claim 15. 18. An ink jet recording apparatus comprising the ink jet head according to claim 14.