JP2001158102A - Method for manufacturing ink jet printer head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an ink jet printer head in which a water repellent film can be formed in a required region of an ejection face and an ejection nozzle of a desired correct shape can be made. SOLUTION: (a) A mask, i.e., a Ti film 44, being used for dry etching an ejection nozzle is formed on an orifice plate 37. (b) A photoresist is applied onto the Ti film 44 and openings 45-1 are made as a mask pattern for etching. (c) Openings 44-1 are then made in the Ti film 44 according to the openings 45-1. (d) Ejection nozzles 39 are made in the orifice plate 37 by dry etching according to the openings 44-1. (e) A dry film photoresist is applied onto the Ti film 44 and then exposed and developed to form a choking film 49 on the openings 44-1. (f) A composite Ni plating film dispersed with PTFE water repellent particles is deposited thereon by electroless plating to form a water repellent film 46. (g) The entirety is immersed into dry film stripping liquid and the choking film 49 comprising the dry film photoresist is removed along with the overlying water repellent film 46.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of manufacturing an ink jet printer head capable of appropriately forming a water-repellent film on a discharge surface and forming a discharge nozzle of a desired shape.

[0002]

2. Description of the Related Art In recent years, ink jet printers have been widely used. Ink jet printers include a thermal method in which ink is heated to generate air bubbles to eject ink droplets under the pressure, and a piezo method in which ink droplets are ejected by deformation of a piezoresistive element (piezoelectric element). In these methods, printing is performed by directly ejecting ink, which is a color material, as ink droplets onto recording paper, and printing energy is lower than that of an electrophotographic method using toner which is a powdery printing material. It is easy to colorize by mixing, and the print dots can be made small, so that high image quality can be obtained, the amount of ink used for printing is not wasted, and the cost performance is excellent. Therefore, it is widely used especially as a personal printer. Printing method.

The above-mentioned thermal system has two configurations depending on the ejection direction of ink droplets. One type is called a side shooter type, which discharges ink droplets in a direction parallel to the heat generating surface of the heating element, and the other discharges ink droplets in a direction perpendicular to the heat generating surface of the heat generating element. This is called a roof shooter type.

FIG. 9 (a) is a plan view schematically showing an ink ejection surface of an ink jet printer head provided in such a roof shooter type ink jet printer, and FIG. 9 (b) is a plan view thereof. -A 'sectional view, FIG.
FIG. 2 is a view showing a silicon wafer on which the inkjet printer head is manufactured.

As shown in FIG. 1C, an ink jet printer head (hereinafter, simply referred to as a print head) 1 is formed on a silicon wafer 2 by an LSI forming technique and a thin film forming technique. Silicon wafer 2
Are individually cut out and collected.

As shown in FIG. 1A, four types of ink of yellow (Y), magenta (M), cyan (C) and black (Bk) are ejected on the ink ejection surface of the print head 1. Four nozzle rows 3 are formed. One nozzle row 3 has a large number of nozzles 4 at, for example, 600 dots / 2.
If the resolution is 5.4 mm, they are arranged in one vertical line at an arrangement pitch of 42.3 μm. Each of the nozzle rows 3 includes a nozzle row 3 from an ink cartridge (not shown) or the like.
Are supplied, respectively.

The internal structure of the print head 1 is shown in FIG.
As shown in FIG. 7, a drive circuit 6 composed of an LSI and a resistance heating section 7 composed of a thin film are formed on a head chip 5, and an individual wiring electrode 8 connecting one end of the resistance heating section 7 and the drive circuit 6 is formed. Further, a common electrode 11 for connecting the other end of the resistance heating section 7 and the power supply terminal 9 is formed. The partition 12 is laminated on these.
The resistance heating portions 7 and the individual drive electrodes 8 are arranged by the number of nozzles 4 of the nozzle row 3 formed later.

An ink supply groove 13 extending in parallel with the nozzle row 3 to be formed later, and the ink supply groove 1
Ink supply holes 14 penetrating the lower surface of the head chip 5 in communication with the orifice plate 15 are formed.
Are laminated by applying heat and pressure to the partition wall 12 with a thermoplastic adhesive on the lower surface. Due to the lamination of the orifice plates 15, an ink passage 16 having a height of about 10 μm corresponding to the thickness of the partition wall 12 is formed between the resistance heating portion 7 and the ink supply groove 13. Thereafter, the above-described nozzles 4 for discharging ink are formed on the orifice plate 15.

If the diameter of the silicon wafer 2 shown in FIG. 1C is, for example, 6 × 25.4 mm, 90 or more head chips 5 as described above can be formed on the silicon wafer. Print head 1 on silicon wafer
The head chips 5 completed as above are cut off individually by cutting each head chip unit along a scribe line of a silicon wafer using a dicing saw or the like,
The separated head chip 5 is die-bonded to a mounting substrate, and terminals are connected to complete the print head 1 in practical units.

In the print head 1, during printing, ink is supplied from an external ink cartridge or the like to the resistance heating section 7 through the ink supply hole 14, the ink supply groove 13, and the ink passage 16. The drive circuit 6 selectively energizes the plurality of resistance heating sections 7 in accordance with the image information to generate a film bubble phenomenon that rapidly expands and disappears at the interface with the ink. Drops are ejected from the ejection nozzle 4 toward the paper surface.

By the way, if the ink droplets discharged toward the paper surface are not cut well from the discharge nozzles as described above, good print dots cannot be formed on the paper surface.
Therefore, in order to improve the cut of the ink droplet from the discharge nozzle, conventionally, a method of performing a surface treatment for adding water repellency to the periphery of the opening of the discharge nozzle on the surface of the orifice plate and the vicinity thereof has been adopted. .

However, if the water-repellent surface treatment is applied to the orifice plate on which the discharge nozzles are formed in advance, the water-repellent agent enters the print head from the discharge nozzles.
This causes a problem that the subsequent smooth supply of ink is adversely affected. Therefore, various methods have been proposed for performing a surface treatment before opening the discharge nozzle so that the surface treatment agent does not adversely affect the inside of the print head.

FIGS. 10 (a) to 10 (e) are views showing a water-repellent treatment step called a subtractive method which has been conventionally proposed, and FIGS. 10 (f) to 10 (j) show other proposed methods. FIG. 4 is a diagram showing a water repellent treatment step called an additive method.

In the subtractive method shown in FIGS. 1A to 1E, first, as shown in FIG. 1A, a Ti film 17 is formed on one surface of a polyimide orifice plate 15. next,
As shown in FIG. 1B, PTFE particles were formed on the upper surface of the Ti film by Ni plating, which can be formed in an electroless manner.
A water-repellent film 18 made of a material dispersed in a plating solution is formed. The water-repellent film 18 is formed of P
It exhibits water repellency by the action of TFE particles.

Subsequently, as shown in FIG.
A photoresist layer 19-1 is laminated on the upper surface of the substrate 8, and the photoresist layer 19-1 has an opening 19-2 in a portion corresponding to the position of the discharge nozzle 4 shown in FIGS. 9 (a) and 9 (b). A resist mask 19 is formed by photolithography technology or the like. Then, openings 21 are formed in the water repellent film 18 and the Ti film 17 as a dry etching mask film by wet etching in accordance with the resist mask 19 described above.
The discharge nozzle 4 is formed in the orifice plate 15 by dry etching according to the opening 21.

In this dry etching, it is preferable to use a helicon wave dry etching method which has strong anisotropy and has a high etching rate for polyimide which is a material of the orifice plate 15. Before performing the dry etching, the resist mask 19 used for the wet etching is removed.

Next, in the additive method shown in FIGS. 1F to 1J, first, as shown in FIG. 1F, a dry etching mask is formed on the upper surface of the polyimide orifice plate 15 as shown in FIG. A Ti film 17 is formed as a film. Next, a photoresist layer 19-1 is laminated on one surface of the Ti film 17 as shown in FIG. 9G, and an opening 19 is formed in a portion of the photoresist layer 19-1 corresponding to the discharge nozzle position. −
2 is formed by photolithography or the like.

Subsequently, an opening 22 is formed in the Ti film 17 by wet etching according to the resist mask 19.
After drilling, the resist mask 19 is removed and the Ti film 1 is removed.
7 is exposed. Then, as shown in FIG. 2I, a water-repellent layer 18 is formed on the exposed surface of the Ti film 17 by Ni plating in which PTFE particles are dispersed, avoiding the opening 22. Subsequently, according to the opening 22, FIG.
As in the case of, by helicon wave dry etching,
As shown in FIG. 7 (j), the discharge nozzle 4 is formed.

In the completed structure of both methods shown in FIGS. 3E and 3J, both the orifice plate 15 and the Ti film 1 are used.
7 and a water-repellent layer 18.

[0020]

However, FIG.
In the processing method by the subtractive method shown in (a) to (e), the water-repellent film 18 formed in advance before the opening of the discharge nozzle 4 by dry etching is wet-etched to form the opening shown in FIG. The PTFE particles are exposed on the inner wall surface of the Ni plating film 21, and roughness is generated on the inner wall of the discharge nozzle 4 opened by dry etching according to the opening 21.

That is, although the shape of the discharge nozzle 4 originally formed by dry etching requires an opening having a circular shape or a shape close thereto, the inner wall surface of the opening 21 serving as a mask pattern for dry etching is required. To PT
If the unevenness due to the exposure of the FE particles occurs, the inner wall surface of the discharge nozzle 4 at the orifice plate 15 becomes rough. As a result, unevenness occurs in the flying direction, amount, speed, and the like of the ejected ink droplet. As described above, when unevenness occurs in the flight direction, amount, speed, and the like of the ink droplet, a problem occurs in that the print dot becomes unstable and the quality of the formed image is reduced.

Another problem is whether a photoresist 19 can be formed with good adhesion on a film layer having water repellency essentially like the water repellent film 18. On the other hand, in the processing method by the additive method shown in FIGS. 10F to 10J, the Ti layer 17 in which the opening 22 is already formed is
It is difficult to selectively form a Ni plating film that becomes the water-repellent film 18 avoiding the opening 22.

When a Ni plating film serving as the water-repellent film 18 is formed electrolessly, a Pd catalyst is usually applied to the surface to be plated as a pretreatment, but this Pd catalyst is applied only on a metal film such as Ni. It is not formed selectively, but is formed on an organic material such as polyimide, which is an orifice plate material, although the adhesion is slightly inferior. That is, the Pd catalyst also adheres to the surface of the orifice plate 15 exposed at the bottom of the opening 22,
Here, a water-repellent film 18 is slightly formed by Ni plating.

Then, even if a hole is formed in the orifice plate 15 by dry etching in this state, the Ni-plated water-repellent film formed on the orifice plate 15 serves as a mask, which only hinders the normal formation of the discharge nozzle 4. However, a problem of lowering the processing rate occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances,
It is an object of the present invention to provide a method of manufacturing an ink jet printer head that can form a water repellent film appropriately on a discharge surface and reliably form a discharge nozzle having a desired shape.

[0026]

According to a first aspect of the present invention, there is provided a method of manufacturing an ink jet printer head including an orifice plate having a plurality of discharge nozzles for discharging ink in a predetermined direction. A method, wherein the step of forming the discharge nozzle in the orifice plate, and corresponding to each of the discharge nozzles of the orifice plate, a blocking film forming step of selectively forming a blocking film that closes the discharge nozzle, A step of applying a water-repellent film having water repellency over a predetermined area of the discharge surface of the orifice plate including the discharge port where the discharge port of the discharge nozzle is formed including the formation area of the blockage film; And a lift-off step for selectively removing the water-repellent film deposited on the closing film.

It is preferable that the closing film is made of a dry film and is disposed so as to cover the discharge port of the discharge nozzle. Further, the blocking film,
For example, it is preferable that a high-viscosity photoresist is formed by filling at least the inside of the discharge nozzle. Further, the blocking film is made of a high-viscosity positive photoresist, for example, as described in claim 4, and the positive photoresist is applied to at least the inside of the discharge nozzle and its periphery, and the applied positive photoresist is applied. The positive photoresist is preferably formed by exposing the entire surface thereof after exposure, and leaving a part of the deposited positive photoresist in the discharge nozzle. The water-repellent film is preferably formed by electroless plating a Ni film in which water-repellent material particles are dispersed and mixed, for example.

Preferably, the discharge nozzle is formed by dry etching using a Ti film as a mask, and the water-repellent film is formed on the Ti film. .

Next, a method of manufacturing an ink jet printer head according to the present invention is a method of manufacturing an ink jet printer head including an orifice plate having a plurality of discharge nozzles for discharging ink in a predetermined direction. A step of installing an etching mask layer in which holes corresponding to the discharge nozzles to be formed in the orifice plate are formed, and selectively forming a blocking film for closing the holes in correspondence with each hole of the mask layer. An occlusion film forming step, a step of applying a water-repellent film having water repellency over a predetermined region of the surface of the mask layer, and selecting the water-repellent film applied on the occlusion film together with the occlusion film. A lift-off step of removing the mask, and a step of forming the discharge nozzle in the orifice plate through the mask layer and the water-repellent film formed on the mask layer. It is. In this case, it is preferable that the discharge nozzle is formed by helicon wave dry etching, for example.

[0030]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1A, 1B, and 1C are diagrams showing a method of manufacturing an ink jet printer head according to the first embodiment in the order of steps, each of which is formed on a silicon chip substrate in a series of steps. FIG. 3 schematically shows a schematic plan view and a cross-sectional view of a state in which the semiconductor device is moved. In these figures, for convenience of explanation, only one print head (the same as the configuration of a mono-color ink-jet printer head) of a full-color ink-jet printer head is shown, but actually, as will be described later. A large number of such print heads (usually four) are formed on a single substrate (silicon chip). FIG. 3 (c) shows 36 discharge nozzles 39, which are actually formed in large numbers, such as 64, 128, 256, etc. according to the design policy.

FIG. 2 (a) is an enlarged plan view of FIG. 1 (a) in the upper part, and a cross-sectional view taken along the line CC 'of the upper part in the middle part.
The lower section shows the DD ′ cross-sectional view of the upper section. Fig. 2 (b)
Is an enlarged plan view of FIG. 1 (b) in the upper part, a cross section of the same part as the middle part in FIG. 2 (a) is shown in the middle part, and FIG. 2 (a) is shown in the lower part.
2 shows a cross section of the same part as the lower part. And FIG.
(c) is an enlarged plan view of FIG. 1 (c) in the upper part, a cross section of the same part as the middle part in FIG. 2 (a) in the middle part, and FIG.
The cross section of the same part as the lower part of (a) is shown. FIG.
(a), (b), and (c) originally have 64 characters for convenience of illustration.
The number of ejection nozzles that should be as large as one, 128, or 256 is represented by five ejection nozzles.

First, a basic manufacturing method will be described. First, as a process 1, a drive circuit and its terminals are formed on a silicon substrate having a size of 4 × 25.4 mm or more by an LSI forming process, and an oxide film (SiO ₂ ) having a thickness of 1 to 2 μm is formed.
Then, in step 2, using a thin film forming technique, tantalum (Ta) -silicon (Si) -oxygen (O)
, And an electrode film made of Au or the like are sequentially laminated with an adhesion layer made of Ti-W or the like interposed therebetween. Then, the electrode film and the resistive heating element film are patterned into stripes by photolithography technology, and wiring electrodes are formed on both sides of a region serving as a heating part on the resistive heating element film having the stripe shape. In this step, the position of the heat generating portion is determined.

FIGS. 1 (a) and 2 (a) show a state immediately after the above steps 1 and 2 are completed. That is, on the surface of the chip substrate 25, a drive circuit 26 and a drive circuit terminal 27 (see FIG. 1A) are formed under an insulating layer made of an oxide film, and a resistance heating element layer is formed on the insulating layer. A plurality of stripes are patterned in parallel at predetermined intervals at predetermined intervals, and a common electrode 29 as a pair of electrodes and an individual wiring electrode 31 are formed at both ends of the heating portion 28. Due to these juxtaposition, a heat generating section row 28 'is formed on the chip substrate 25.
And an individual wiring electrode array 31 '. And
A common power supply terminal 32 is formed on the common electrode 29 (see FIG. 1A).

Subsequently, as a step 3, the individual heating parts 28
In order to form ink pressurizing chambers corresponding to the above and an ink flow path for supplying ink to these ink pressurizing chambers, a partition layer made of an organic material such as photosensitive polyimide is formed to a height of about 20 μm by coating, and this is formed. After patterning by the photolithography technique, heat of 300 to 400 ° C. is applied for 30 minutes.
Then, curing (dry curing, baking) is performed for a period of from 60 minutes to 60 minutes, and a partition made of the photosensitive polyimide having a height of about 10 μm is formed and fixed on the head chip. Further, in step 4, a groove-shaped ink supply path is formed on the surface of the chip substrate by wet etching or sand blasting, and an ink supply hole that opens to the back surface of the chip substrate by communicating with the ink supply path is formed. I do.

In step 4, since the shapes of the ink supply path on the front side where the heat generating portion, the electrodes, the partition walls, etc. are formed, and the ink supply hole on the back side are different, processing is performed separately from the front and back. For example, an ink supply path is formed on the front side to about half the thickness of the head chip, and an ink supply hole is formed from the back side to penetrate the front and back.

FIGS. 1 (b) and 2 (b) show a state immediately after the above-mentioned steps 3 and 4 are completed. That is, the groove-shaped ink supply path 33 and the ink supply hole 34 are formed, and the common electrode 2 located on the left side of the ink supply path 33 is formed.
9 and the portion where the individual wiring electrode 31 on the right side is disposed, and between each heat generating portion 28,
(Seal partition 35-1, 35-2, partition 35-3)
Are formed. The above-mentioned partition wall 35 is formed of the individual wiring electrode 3.
Assuming that the upper seal partition 35-2 is a comb body, the partition 35-3 extending between the heat generating portions 28 has a shape corresponding to the teeth of the comb. Thereby, the fine ink pressurizing chamber 36 in which the heat generating portion 28 is located at the base between the teeth partitioned by the comb tooth-shaped partitioning wall 35-3 as a partition wall, the number of heat generating portions 28 Only be formed.

Thereafter, in step 5, an orifice plate of a polyimide film having a thickness of 10 to 30 μm was used, and thermoplastic polyimide as an adhesive was coated on both surfaces or one surface to an extremely thin thickness of, for example, 2 to 5 μm. The state, placed on the uppermost layer of the laminated structure, that is, the partition,
While heating at 200 to 250 ° C. in vacuum, 9.8 × 1
Pressure is applied at a pressure several times greater than 0 ^-4 Pa, and this is continued for several tens of minutes to fix the orifice plate. Subsequently, a metal film having a thickness of about 0.5 to 1 μm, such as Ni, Cu, Al or Ti, is deposited on the surface of the orifice plate by a vacuum device or a sputtering device.

In step 6, the metal film on the surface of the orifice plate is patterned to form a mask for selectively etching polyimide. Subsequently, as will be described in detail later, with a process of selectively forming a water-repellent film in a region other than the discharge nozzle forming region, 20 μmφ to 40 μmφ as a discharge nozzle according to the above metal film mask by dry etching using a helicon wave. A large number of holes are formed in the orifice plate at once.

FIGS. 1 (c) and 2 (c) show the process 5 described above.
And the state immediately after the end of step 6. That is, the orifice plate 37 covers the entire area except for the common power supply terminal 32 and the drive circuit terminal 27, whereby the fine ink pressurizing chamber 36 having a height corresponding to the thickness of the partition wall 35 of 10 μm is formed. An ink flow path 38 having a height of 10 μm that connects the ink pressurizing chamber 36 and the ink supply path 33 is completed.

The orifice plate 37 has a discharge nozzle 39 at a position facing the heat generating portion 28 of the ink pressurizing chamber 36.
Are formed by dry etching. As a result, a large number of monocolor ink jet printer heads 40 having a large number of ejection nozzles 39 such as 64, 128 or 256 in one row are completed on a silicon wafer.

In this way, after the orifice plate 37 is attached and the discharge nozzle 39 is processed in accordance with the pattern of the base, that is, the position of the heat generating portion 28, the orifice plate 37 on which the discharge nozzle 39 has been processed in advance is bonded. It is a much more productive and practical method.
In the case of dry etching, the mask is Ni,
By using a metal film such as Cu, Al or Ti, a selectivity between the resin and the metal film of about 100 can be obtained. Therefore, to etch a polyimide film of 20 to 40 μm, it is sufficient to form a mask with a metal film of 1 μm or less.

The processing up to this point is performed in the state of a silicon wafer. Finally, in step 7, the silicon wafer is cut along a scribe line using a dicing saw or the like, divided into individual head chip units, die-bonded to a mounting substrate, and connected to terminals for practical use. Is completed.

In normal full-color printing, black (Bk) dedicated to black portions of characters and images is added to three subtractive primary colors, yellow (Y), magenta (M), and cyan (C). Requires a total of four colors of ink. Therefore, at least four nozzle rows are required.
According to the above-described manufacturing method, the mono-color ink jet printer head 40 can be monolithically formed into four rows, and the positional relationship between the nozzle rows of each head can be accurately arranged by today's semiconductor manufacturing technology. It is possible.

FIG. 3A shows the chip substrate 25, the drive circuit 26, the drive circuit terminal 27, the heat generating portion 28, the common electrode 29, the common electrode power supply terminal 32, the individual wiring electrode shown in FIGS. 31, an ink supply path 33, an ink supply hole 34,
A head element, ie, a mono-color ink jet printer head 40, which constitutes a set of the partition wall 35, the orifice plate 35, the ink pressurizing chamber 36, the ink flow path 38, and the discharge nozzle 39 as one set, is arranged in four rows on a chip substrate 41 which is slightly divided. FIG. 4 is a diagram illustrating a state in which a full-color ink jet printer head is formed, and four nozzle rows 43 (43a, 43b, 43c, and 43d) are formed on one chip substrate 41. FIG. 3 (b) shows the configuration of FIG. 3 (a) in a manner that the mono-color inkjet printer heads 40 are arranged in four rows for easy understanding.
This shows a state in which steps 1 and 2 shown in FIG. 1A have been completed.

As shown in FIGS. 3 (a) and 3 (b), the full-color ink jet printer head 42 is a mono color ink jet printer head 40 (40a, 40a).
b, 40c, 40d) are arranged side by side. Then, for example, yellow ink is supplied from the ink supply path 33a to the individual ink pressurizing chambers 36 of the mono-color ink jet printer head 40a, and is discharged from the nozzle rows 43a. Further, magenta ink is supplied from the ink supply path 33b to the individual ink pressurizing chambers 36 of the mono-color ink jet head 40b, and is discharged from the nozzle row 43b. Further, cyan ink is supplied from the ink supply path 33c to the individual ink pressurizing chambers 36 of the mono-color inkjet head 40c, and is discharged from the nozzle row 43c.
Then, the black ink is supplied from the ink supply path 33d to the individual nozzle rows 43d of the monocolor inkjet head 40d, and is discharged from the nozzle rows 43d.

In the present invention, in the step 6 in the above-described basic manufacturing method, the orifice plate 3
When a water-repellent film is formed and the discharge nozzle 39 is pierced, special measures are taken to prevent the liquid water-repellent film agent, which is the material of the water-repellent film, from entering the orifice. . This will be described below.

FIGS. 4A to 4G are views showing a process of forming a water-repellent film and a discharge nozzle 39 on the orifice plate 37 in the first embodiment. FIGS. 7A to 7G show only the orifice 37 attached and laminated on the partition wall 35 shown in FIGS.

As shown in FIG. 4A, first, for example, a Ti film 44 is formed on one surface of the orifice plate 37 as a mask at the time of dry etching for forming a discharge nozzle.
It is formed with a thickness of μm to 1 μm. Next, as shown in FIG. 2B, a photoresist 45 is laminated on the upper surface of the Ti film 44, and an opening 45-1 is formed in a portion corresponding to the discharge nozzle position of the photoresist 45 by a photolithography technique or the like. To form an etching resist mask.

Then, as shown in FIG. 3C, an opening 44-1 is formed in the Ti film 44 by wet etching according to the opening 45-1 of the etching resist mask. Further, as shown in FIG. 4D, a discharge nozzle 39 is formed in the orifice plate 37 by dry etching in accordance with the opening 44-1 of the Ti film 44. In this example,
It is processed by a helicon wave type dry etching apparatus which is rich in anisotropy and has a large etching rate of polyimide as a material of the orifice plate 37.

Subsequently, as described above, the discharge nozzle 39 is covered with a dry film photoresist on one surface of the holed Ti film 44, and a mask (not shown) having a predetermined pattern is formed thereon to expose the film. After removing unnecessary parts,
As shown in FIG. 9E, the dry film photoresist is selectively left over the opening 44-1 to form the closing film 49, thereby closing the opening 44-1.

In this case, the dry film photoresist may be a positive type photoresist (a type in which a portion irradiated with light is softened and removed) or a negative type photoresist (a portion in which the portion irradiated with light is cured. Or the remaining type), and the closing film 49 having the same shape can be formed by using a mask having a pattern matching the characteristics of positive and negative.

Then, from above, a Ni film in which PTFE particles are dispersed is subjected to electroless plating to form a water-repellent film 46 as shown in FIG. Finally, when the whole is immersed in a dry film stripper, the Ni plating film (water-repellent film) also formed on the blocking film 49 is peeled off (lift-off) together with the blocking film 49 as shown in FIG. ) Can be.

As described above, before forming the water-repellent film, the discharge nozzles (see the discharge nozzles 39 in FIG. 4D) are collectively formed in a desired appropriate shape. Since the water-repellent film is formed in a state in which the water-repellent film is temporarily closed by the closing film, it is possible to prevent a problem that the water-repellent film agent enters the head from the discharge nozzle and the head becomes defective. As a result, a good ink-jet head having a discharge nozzle of an appropriate shape can be obtained, and the problem that unevenness occurs in the flying direction, amount, speed, etc. of the discharged ink droplet is eliminated, and a high-quality image is formed. It becomes possible.

As shown in FIG. 9G, the opening 46-1 formed in the “Ni + PTFE” water-repellent film 46 after the removal of the blocking film 49 is formed by placing the blocking film 49 on the Ti film 44. As the retained area, the periphery is formed wider by the width X1 than the opening 44-1 of the Ti film 44. Assuming that the thickness of the blocking film 49 is about 12.5 μm, which is usually considered to be the thinnest, in order to secure the bridging strength of the blocking film 49 when this is held in the opening 44-1 of the Ti film 44. Requires a width X1 of about 10 μm.

The portion having the width X1 is the periphery of the opening 44-1 of the discharge nozzle 39 and is not subjected to the water-repellent treatment, though it is the region requiring the most water-repellent treatment. Therefore, there is a possibility that the so-called sharpness of the ejected ink droplets deteriorates and the print quality deteriorates. Therefore, it is better that the width X1 is as narrow as possible. A manufacturing method capable of forming a smaller difference in width between the opening of the water-repellent film 46 and the opening of the discharge nozzle 39 (the opening 44-1 of the Ti film 44) will be described below as a second embodiment. Will be described.

FIGS. 5A to 5G are views showing a process of forming the water-repellent film 46 and the discharge nozzle 39 on the orifice plate 37 in the second embodiment. 4 (a) to 4 (d) are the same as the steps from FIG. 4 (a) to FIG. 4 (d). In this example, in the next step, instead of a dry film,
Using a high-viscosity photoresist, the high-viscosity photoresist is applied to the entire surface of the orifice plate 37, that is, the Ti film 44. In this case, the viscosity of the photoresist is reduced by opening 4.
4-1 is set so that a part of the portion applied on 4-1 enters the opening 44-1 but does not flow out of the discharge nozzle 39. After irradiating the photoresist coated in this way with light through a mask (not shown) and exposing the photoresist,
Unnecessary portions are removed by development to form a blocking film 47 as shown in FIG.

In the case of the present example, as described above, a part of the blocking film 47 is allowed to enter the opening 44-1 and the blocking film 47 is substantially held by the Ti film 44 at the entered portion. It is not necessary to hold the closing film 47 around the opening 44-1 of the Ti film 44, and the dimension X2 shown in FIG.
(The same as the width X2 of (g)) is sufficient for the alignment accuracy at the time of exposing the photoresist before being formed into the closing film 47, specifically, a size of about 1 μm. in this case,
The viscosity of the photoresist 47 is determined by the diameter and shape of the discharge nozzle.

Thereafter, as shown in FIGS. 4F and 4G, the same processing as in FIGS. 4F and 4G is performed, and the openings 46-of the water-repellent film 46 are formed. 1 and the opening of the discharge nozzle 39 (Ti
An ink jet printer head is completed in which the difference X2 in width between the film 44 and the opening 44-1) is smaller than the width X1 in FIG.

In each of the first and second embodiments, the water-repellent film 46 is provided on the entire surface of the orifice plate. However, the water-repellent film is required for ink droplets discharged from the discharge nozzle. Therefore, as long as only the surface around the opening of the discharge nozzle has water repellency, the purpose of performing sharp discharge can be achieved even if the surface of the other part does not have water repellency. A method of manufacturing an ink jet printer head having such a configuration will be described below as a third embodiment.

FIGS. 6A to 6G are diagrams showing a process of forming a water-repellent film and a discharge nozzle 39 on the orifice plate 37 in the third embodiment. 5A to FIG. 5D are the same as the steps from FIG. 5A to FIG. 5D. Also in this example, a high-viscosity photoresist is used in the next step. In the case of this example, as shown in FIG.
Instead, only the peripheral portion 47-1 having a predetermined width is removed from the peripheral end surface of the closing film 47, and the plating mask film 47-2 is also left on the entire outer peripheral surface.

Then, in FIG. 6 (f) and FIG. 6 (g), when the same processing as in FIG. 5 (f) and FIG. 5 (g) is performed, The formed water repellent film 4
6 remains, and the others are the blocking film 47 and the plating mask film 47.
-2 is lifted off together with the opening of the discharge nozzle 39,
That is, an ink jet printer head having the water repellent film 46 only on the surface around the opening 44-1 of the Ti film 44 is completed.

As described above, by performing a surface treatment for selectively imparting water repellency only to the peripheral edge of the opening of the discharge nozzle, ink is applied to the peripheral edge of the discharge nozzle of the orifice plate during printing by the ink jet printer head. Even if the ink adheres, the adhering ink flows toward the non-water-repellent surface outside the ejection nozzle opening periphery due to the water repellency of the opening periphery, so that there is a remarkable effect that the next ink ejection is not adversely affected. Can be

In the second and third embodiments, T
About 1 μm around the discharge nozzle opening 44-1 of the i film 44
An area that cannot be treated with the water repellency of the width is formed.
A portion without water repellency may not be formed at all around the discharge nozzle opening 44-1. A method for manufacturing an ink jet printer head in which a portion having no water repellency is not formed at all around the discharge nozzle opening 44-1 will be described below as a fourth embodiment.

FIGS. 7A to 7H are views showing the steps of forming a water-repellent film and discharge nozzles 39 on the orifice plate 37 in the fourth embodiment. 6 (a) to 6 (d) are the same as the steps from FIG. 6 (a) to FIG. 6 (d). Also in this example, a positive-type, high-viscosity photoresist is used in the subsequent process, but in this example, as shown in FIG. Discharge nozzle 3
After forming and drying a photoresist layer 47 'penetrating to the upper portion of 9, the entire surface of the photoresist layer 47' is irradiated with an appropriate amount of ultraviolet light without using a mask for exposure.

In this exposure, exposure is performed by adjusting the amount of light so that ultraviolet rays do not reach the lowermost part of the positive photoresist layer 47 ′ that has entered the upper part of the discharge nozzle 39. Thereafter, when development is performed, as shown in FIG. 9F, all other resist portions are removed, leaving only the lowermost portion of the photoresist that has entered the upper portion in the discharge nozzle 39 as the closing film 47. .

Thereafter, as shown in FIG. 3G, a water repellent film 46 of a composite nickel plating film made of "PTFE + Ni" is formed by electroless plating. The water-repellent film 46 is made of Ti
It is formed not only on the surface of the film 44 but also on the closing film 47 remaining in a shape extending over the inside of the discharge nozzle 39,
By immersing in the photoresist removing liquid, the closing film 4
7, only the water-repellent film 46 is selectively removed together with the blocking film 47 made of photoresist. As a result,
As shown in (h), the water-repellent film 4 that follows the periphery of the discharge port from which ink is discharged, that is, the opening 44-1 of the Ti film 44 in this example.
No ink-repellent portion is present at the periphery of the opening 46-1 of No. 6, in other words, an ink-jet printer head having water-repellency with no gaps over the entire ejection surface where the ink ejection ports are formed is completed.

In each of the first to fourth embodiments, the manufacturing method of forming the water-repellent film after forming the discharge nozzle has been described. However, the water-repellent film is formed first, and then the discharge nozzle is formed. Even so, the water-repellent material can be prevented from adversely affecting the formation of the discharge nozzle. This will be described below as a fifth embodiment.

FIGS. 8A to 8G are views showing a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the fifth embodiment. Fig. 6 (a) is the same as Fig. 6 (a) to Fig. 6 (c).
6 to FIG. 6C. In this example, in the next step, a normal positive or negative photoresist is applied to the entire surface and exposed through an appropriate mask, and as shown in FIG. -1 is covered with a closing film 48 made of a photoresist.

After that, as shown in FIG.
6 is formed, and then the blocking film 48 and the water-repellent film 46 on the blocking film 48 are both removed by a lift-off method.
As shown in (f), the surface of the orifice plate 37 is exposed in the opening 44-1 of the Ti film 44, and thereafter, as shown in FIG. The discharge nozzle 39 is bored in the orifice plate 37 by dry etching to complete the ink jet printer head.

As described above, after the metal mask for forming the discharge nozzle is patterned, the patterned opening is covered with the photoresist, and then the water-repellent film is formed. Therefore, the orifice plate not covered with the metal mask is formed. The surface of the orifice plate to be exposed to the opening and subjected to dry etching is also provided on the surface of the water-repellent film material “Ni + P”.
The conventional disadvantage that a TFE "film is formed and the etching rate is reduced is eliminated.

Further, in this case, since the discharge nozzle is not formed at the stage of applying and forming the water-repellent film, there is an advantage that the intrusion of the liquid material of the water-repellent film into the print head can be more reliably prevented. .

Although the composite Ni plating solution in which PTFE particles are dispersed is used for the formation of the water-repellent film, the present invention is not limited to the composite Ni plating solution in which PTFE particles are dispersed. Applicable. In the various embodiments described above, the Ti film is used as a base for electroless plating, but the base for electroless plating is not limited to metal. Further, the present invention is applicable not only to the case where the discharge nozzle is formed by helicon wave dry etching but also to the case where the discharge nozzle is formed by wet etching.

[0073]

As described above in detail, according to one method of the present invention, after a discharge nozzle formed in an appropriate shape is closed with a blocking film, a desired area on the ink discharge side surface of the orifice plate is formed. Since the water-repellent film with water-repellency is applied, the inside of the inkjet head having the discharge nozzle of a desired and appropriate shape and having the water-repellent film in a required area of the discharge surface is not contaminated with the water-repellent film material. This makes it possible to easily manufacture the ink droplets, thereby eliminating the problem that unevenness occurs in the flying direction, amount, speed, etc. of the ejected ink droplets, and it is possible to form a high-quality image.

Further, according to another method of the present invention, the water-repellent film is formed in such a manner that the opening corresponding to the discharge nozzle to be formed after the etching mask for forming the discharge nozzle is covered with the blocking film. The conventional defect that the water-repellent film material adheres to the surface of the orifice plate where the discharge nozzle is not formed because the mask is not covered with the water-repellent film material, thereby causing a poor etching of the discharge nozzle such as a decrease in an etching rate. Is eliminated.

Further, according to this method, since the discharge nozzle is not formed in the step of forming the water-repellent film, it is possible to more reliably suppress the liquid-repellent film material liquid from entering the inside of the print head. It is possible to reliably prevent the adverse effects that occur in the discharge nozzles and the ink flow paths due to the penetration of the water film material liquid into the print head.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are schematic plan views and cross-sectional views showing a method of manufacturing an ink jet printer head according to a first embodiment in the order of steps.

FIG. 2 (a), (b), and (c) show the upper part of FIG. 1 (a), (b),
(c) is an enlarged plan view, the middle part is a view showing an upper section taken along a line CC ′, and the lower part is a view showing an upper part taken along a DD ′ section.

FIG. 3A is a schematic plan view of a full-color inkjet printer head, and FIG. 3B is a schematic plan view showing an internal configuration thereof.

FIGS. 4A to 4G are diagrams showing a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the first embodiment.

FIGS. 5A to 5G are diagrams showing a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the second embodiment.

FIGS. 6A to 6G are diagrams illustrating a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the third embodiment.

FIGS. 7A to 7H are views showing a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the fourth embodiment.

FIGS. 8A to 8G are diagrams showing a process of forming a water-repellent film and a discharge nozzle on an orifice plate in the fifth embodiment.

FIG. 9A is a plan view schematically showing an ink ejection surface of a conventional ink jet printer head, and FIG.
FIG. 3C is a view showing a silicon wafer on which an ink jet printer head is manufactured, as viewed from an arrow A ′.

FIGS. 10 (a) to (e) are views showing a conventionally proposed water repellent treatment step called a subtractive method, and FIGS. 10 (f) to 10 (j).
FIG. 3 is a view showing a water-repellent treatment step called an additive method that has been proposed.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Print head 2 Silicon wafer 3 Nozzle row 4 Discharge nozzle 5 Head chip 6 Drive circuit 7 Resistance heating part 8 Individual wiring electrode 9 Power supply terminal 11 Common electrode 12 Partition wall 13 Ink supply groove 14 Ink supply hole 15 Orifice plate 16 Ink passage 17 Ti film 18 Water-repellent film 19 Resist mask 19-1 Photoresist layer 19-2 Opening 21, 22 Opening 25 Chip substrate 26 Drive circuit 27 Drive circuit terminal 28 Heating section 28 'Heating section row 29 Common electrode 31 Individual wiring electrode 31' Individual wiring electrode array 32 Common power supply terminal 33, 33a, 33b, 33c, 33d Ink supply path 34 Ink supply hole 35 Partition 35-1, 35-2 Seal partition 35-3 Partition partition 36 Ink pressurizing chamber 37 Orifice plate 38 Ink flow path 39 Discharge nozzle 40 (40a, 40b, 40 40d) Mono-color inkjet printer head 41 Chip substrate 42 Full-color inkjet printer head 43 (43a, 43b, 43c, 43d) Nozzle row 44 Ti film 44-1 opening 45 Photoresist 45-1 opening 46 Water-repellent film 46-1 opening 47, 48, 49 Occlusion film 47 'Photoresist layer

Claims (8)

[Claims] 1. A method of manufacturing an ink jet printer head including an orifice plate having a plurality of discharge nozzles for discharging ink in a predetermined direction, comprising: forming the discharge nozzle on the orifice plate; A blocking film forming step of selectively forming a blocking film for closing the discharge nozzle in correspondence with each of the discharge nozzles, and forming a discharge port of each of the discharge nozzles of the orifice plate including a formation region of the blocking film. Applying a water-repellent film having water repellency over a predetermined region of the ejected surface, and a lift-off step of selectively removing the water-repellent film attached on the closing film together with the closing film; A method for manufacturing an inkjet printer head, comprising: 2. The method according to claim 1, wherein the closing film is made of a dry film, and is disposed so as to cover a discharge port of the discharge nozzle. 3. The method according to claim 1, wherein the blocking film is formed by filling a high-viscosity photoresist at least in the discharge nozzle. 4. The blocking film is made of a high-viscosity positive photoresist, and the positive photoresist is applied to at least the inside of the discharge nozzle and the periphery thereof, and the entirety of the applied positive photoresist is applied. 4. The method according to claim 3, wherein the surface is exposed to light and then developed to leave a part of the positive photoresist deposited in the discharge nozzle. 5. The method according to claim 1, wherein the water-repellent film is formed by electroless plating a Ni film in which water-repellent material particles are dispersed and mixed. 6. The method according to claim 1, wherein the discharge nozzle is formed by dry etching using a Ti film as a mask, and the water-repellent film is formed on the Ti film. Method. 7. A method for manufacturing an ink jet printer head including an orifice plate having a plurality of discharge nozzles for discharging ink in a predetermined direction, wherein a hole corresponding to a discharge nozzle to be formed in the orifice plate is formed. Providing a masking layer for etching, forming a plugging film corresponding to each hole of the mask layer, and selectively forming a plugging film closing the hole; and covering a predetermined region on the surface of the mask layer. A step of depositing a water-repellent film having water repellency, a lift-off step of selectively removing the water-repellent film deposited on the blocking film together with the blocking film, and the mask layer and the mask layer Forming the discharge nozzle on the orifice plate via the water-repellent film formed in the step (c). 8. The method according to claim 7, wherein the discharge nozzle is formed by helicon wave dry etching.