JP7066449B2 - Manufacturing method of liquid discharge board and manufacturing method of liquid discharge head - Google Patents

Description

The present invention relates to a method for manufacturing a substrate used for a liquid discharge head (hereinafter, referred to as a “liquid discharge substrate”) and a method for manufacturing a liquid discharge head.

As a means for forming a liquid flow path on a liquid ejection substrate, methods such as drilling, laser, and sandblasting, and etching methods such as crystal anisotropic etching and dry etching using an etching gas have been proposed. Among these, the method of forming a liquid flow path by dry etching using an etching gas can form a liquid flow path having a shape substantially perpendicular to the substrate plane. Such a method of forming a liquid flow path by dry etching makes it possible to reduce the chip size as compared with the case where the liquid flow path is formed by crystal anisotropic etching.

As an example of a liquid discharge substrate, Patent Document 1 describes a configuration in which a wiring layer is arranged on an upper part of a liquid flow path. This wiring layer covers a heat generation resistance layer, which is a plurality of electric heat conversion elements that generate heat energy used for discharging liquid, and an aluminum-based wiring for supplying electric power to the heat generation resistance layer. For example, it is composed of a protective layer having an insulating property such as silicon nitride.

By the way, one of the dry etching methods is reactive ion etching. Reactive ion etching is a method in which a reaction gas is generally introduced into a processing chamber to be turned into plasma, and the treated surface of the substrate is etched with the plasmaized reaction gas to form a predetermined shape. Specifically, first, the substrate is fixed to the lower electrode in the processing chamber by, for example, an electrostatic chuck, and the reaction gas is supplied from the micropores of the upper electrode to which the high frequency power supply is connected to the lower electrode. Subsequently, the supplied reaction gas is turned into plasma between the upper electrode and the lower electrode, and the substrate is etched to form a predetermined shape.

Japanese Unexamined Patent Publication No. 2001-71502

In the manufacture of a liquid discharge substrate, it is required to reduce the chip size and increase the number of chips that can be manufactured from one wafer by efficiently arranging the wiring from the viewpoint of cost reduction. Further, from the viewpoint of increasing the printing speed, it is required to reduce the ink flow resistance by widening the liquid flow path of the substrate. When doing these, it is conceivable to arrange the wiring on the upper part of the liquid flow path as in the structure described in Patent Document 1.
However, in the case of adopting such a configuration, when the liquid flow path is widened, the layer including the wiring becomes an eaves structure, and cracking and distortion of the wiring due to insufficient mechanical strength become a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid discharge substrate and a liquid discharge head in which the mechanical strength of the wiring layer is improved in a structure in which the wiring layer is arranged above the liquid flow path. ..

The method for manufacturing a liquid discharge substrate of the present invention includes a silicon substrate, a wiring layer provided on the silicon substrate and including a pressure generating element for liquid discharge and a wiring for supplying power to the pressure generating element, and the wiring. It has a first liquid flow path including a groove provided by processing the silicon substrate under the layer, and a second liquid flow path that communicates with the first flow path and penetrates the wiring layer. A method for manufacturing a liquid discharge substrate, which is a step of providing the wiring layer on the silicon substrate and reactive ion etching from a surface of the silicon substrate opposite to the side on which the wiring layer is provided via a mask. The mask comprises a step of forming the first liquid flow path and a step of forming the second liquid flow path communicating with the first liquid flow path in the wiring layer. The first opening pattern region including the region corresponding to the region forming the second liquid flow path of the wiring layer and including the opening pattern A extending in the first direction is coupled to the opening pattern A. A second opening pattern region comprising an opening pattern B extending in a second direction intersecting the first direction, wherein the opening pattern B is the smallest opening of the opening pattern A. A groove having an opening width narrower than the width is provided at the end portion on the extending direction side in the second direction, and a groove formed corresponding to the opening pattern B when reactive ion etching is performed via the mask. This is a method for manufacturing a liquid discharge substrate, which comprises leaving the silicon of the silicon substrate on the bottom of the liquid.

According to the manufacturing method of the present invention, it is possible to provide a liquid discharge substrate and a liquid discharge head having improved mechanical strength of the wiring layer in a structure in which the wiring layer is arranged above the liquid flow path.

It is a schematic diagram for demonstrating the structure of an example of a liquid discharge head in a related technique. It is sectional drawing for explaining the structure (the structure which arranged the wiring layer in the upper region of the 1st liquid flow path) of another example of a liquid discharge head in a related technique. It is sectional drawing for explaining the structure of an example of the liquid discharge substrate in this invention. It is a dimensional view of the 1st liquid flow path of an example of a liquid discharge substrate in this invention. It is sectional drawing for demonstrating another example of the liquid discharge substrate in this invention. It is a plane schematic diagram which shows the formation example of the 2nd liquid flow path in the wiring layer of the liquid discharge substrate in this invention. It is sectional drawing for demonstrating another example of the liquid discharge substrate in this invention. It is a process diagram (schematic sectional view according to the process order) for demonstrating an example of the manufacturing method of the liquid discharge substrate which concerns on this invention.

Hereinafter, the liquid discharge substrate according to the embodiment of the present invention will be described with reference to the drawings. In the embodiments described below, specific descriptions may be given in order to fully explain the present invention, but these are technically preferable examples, and the scope of the present invention is particularly limited. not.

1 (a) and 1 (b) show an example of a liquid discharge head in a related technique. 1 (a) is a schematic plan view of the liquid discharge head as viewed from the liquid discharge surface side, and FIG. 1 (b) is a schematic cross-sectional view taken along the line aa'of FIG. 1 (a).

In this liquid discharge head, the first liquid flow path 4 formed on the silicon substrate 3, the second liquid flow path 13 formed on the wiring layer 1, and the pressure generating chamber 5 communicate with each other. A configuration in which a liquid is supplied to the pressure generating chamber 5 through the first liquid flow path 4 and the second liquid flow path 13, and the pressure generating element 2 is driven to discharge the liquid from the discharge port 6 of the nozzle plate member 20. Is taken. The wiring layer 1 includes wiring for supplying electric power for driving the pressure generating element 2.

In the manufacture of a liquid discharge substrate, from the viewpoint of cost reduction, it is required to reduce the chip size and increase the number of chips taken from the wafer by efficiently arranging the wiring. Further, from the viewpoint of increasing the printing speed, it is required to reduce the ink flow resistance by expanding the first liquid flow path 4. In order to cope with these, as shown in FIG. 2 (schematic cross-sectional view corresponding to the cross section along the aa' line of FIG. 1A), the upper part of the first liquid flow path 4 (pressure generation). It is conceivable to extend and arrange a layer (wiring layer 1) including wiring on the boundary portion with the chamber 5. In this case, the wiring layer 1 arranged in the upper region 7 of the first liquid flow path 4 has an eaves structure. In such a structure, the wiring is cracked, distorted, etc. due to physical impact (transport operation, ultrasonic treatment, chemical solution cleaning, etc.) in the manufacturing process after processing the first liquid flow path 4, and the steps are taken. It causes a decrease in retention.

In FIGS. 3A, 3B, C, and 3D, the mechanical strength of the wiring layer 1 can be maintained while the wiring layer 1 is arranged in the upper region 7 of the first liquid flow path 4. An example of the liquid discharge substrate according to the embodiment of the present invention is shown. FIG. 3 (a) shows a schematic cross-sectional view corresponding to the cross section along the line aa'of FIG. 1 (a). FIG. 3B is a schematic cross-sectional view taken along the line aa'of FIG. 3A. FIG. 3 (c) is a schematic cross-sectional view taken along the line bb'b' of FIG. 3 (a). FIG. 3 (d) is a schematic plan view along the line c-c'of FIG. 3 (a).

The processing of the first liquid flow path 4 is performed by reactive ion etching from the surface of the silicon substrate opposite to the wiring layer 1 via a mask. The groove formed on the silicon substrate by reactive ion etching becomes the first liquid flow path.

The pattern of the etching mask for forming the first liquid flow path 4 is a pattern including an uneven opening so as to correspond to the shape shown in FIG. 3 (d). This mask pattern is shown in FIG. 8 (c). The mask 10 includes a first opening pattern region including an opening pattern A corresponding to a groove communicating with the first liquid flow path, and an opening pattern B corresponding to a groove serving as a liquid flow path under the wiring layer. It has two aperture pattern areas.

This mask pattern is a strip-shaped opening pattern A extending in the first direction so as to include a region corresponding to a region in which the second flow path 13 is formed (a rectangular pattern extending in the vertical direction of the paper surface in the drawing). ) 31 is included. Further, a plurality of strip-shaped opening patterns B (rectangular patterns extending in the lateral direction of the paper surface in the drawing) that are coupled to the band-shaped opening pattern A and extend (in the second direction intersecting the first direction). 32 is included. Here, the second direction is orthogonal to the first direction. The opening patterns B are arranged at regular intervals along the first direction to form an uneven pattern region. At that time, each opening pattern B (corresponding to the concave portion of the concave-convex pattern region) faces the end of the pattern so as to individually correspond to the pressure generating element and / and the region forming the second liquid flow path. It is preferable that it is arranged. In this example, the opening pattern B extends in the second direction orthogonal to the first direction, but the extending direction (second direction) of the opening pattern B intersects the first direction. You just have to. More specifically, the angle formed with respect to the direction orthogonal to the first direction is preferably, for example, 45 degrees or less, and more preferably 30 degrees or less. Further, it is more preferably 10 degrees or less, and particularly preferably 5 degrees or less.

By doing so, in reactive ion etching, it is possible to obtain a microloading effect in which the etching rate becomes slow in the dense portion of the etching pattern and the etching rate becomes high in the coarse portion. Due to this effect, during the etching process for forming the groove to be the first liquid flow path 4, the etching rate at the wall of the groove 9 corresponding to the opening pattern B is a wide and linear groove corresponding to the band-shaped opening pattern A. Slow with respect to the etching rate in the formation of. Correspondingly, the cross-sectional shape of the first liquid flow path 4 follows the cross-sectional shape of FIG. 3 (c) as the etching depth becomes deeper than the shape of FIG. 3 (d) at the etching start portion. The opening is narrowed as shown in the cross-sectional shape of FIG. 3 (b). As a result, as shown in FIG. 3A, the silicon 8 at the bottom of the wiring layer is located at the bottom of the wiring layer portion (the bottom of the groove 9 corresponding to the recess) directly above the first liquid flow path 4 (upper region 7). As a result, the silicon that is part of the silicon substrate can be left.

4 (a) and 4 (b) show dimensional views of the first liquid flow path of the liquid discharge substrate. FIG. 4A is a schematic plan view of the side opposite to the side where the wiring layer of the liquid discharge substrate is located (the back surface side of the silicon substrate). FIG. 4B is a schematic cross-sectional view taken along the line aa'of FIG. 4A, which corresponds to FIG. 3A.

The thickness F of the silicon left in the groove 9 corresponding to the recess (opening pattern B) constituting the first liquid flow path 4 shown in FIG. 4B is preferably 10 μm or more, more preferably 20 μm or more. By arranging the lower silicon 8 of the wiring layer having such a thickness in the recess (groove), it is possible to improve the mechanical strength of the wiring layer portion of the upper region 7 (directly above region) of the liquid flow path 4. .. The thickness F of the lower silicon 8 of the wiring layer can be formed to be 400 μm or less, and preferably 300 μm or less.

In FIG. 3A, the wiring layer lower silicon 8 is present on the entire surface of the wiring layer portion in the upper region 7 of the first liquid flow path on the first liquid flow path side. The liquid discharge substrate according to the present embodiment is not limited to the presence of the silicon 8 under the wiring layer on the entire surface as described above, and is not limited to a portion not present in a part within the range where the desired strength can be obtained, for example, the first. There may be a portion that does not exist in the vicinity of the liquid flow path of 2.

The first liquid of dimensions A, B, C, D, E, F shown in FIGS. 4 (a) and 4 (b) using the mask of dimensions A, B, C, D shown in FIG. 8 (c). The dimensional relationship of the flow path can be obtained.

In order to leave the silicon 8 under the wiring layer in the groove 9 corresponding to the opening pattern B, it is preferable that the relationship between the dimensions A and C is A> C. For example, as shown in FIG. 8 (c), it is preferable that A> C and the relationship between the dimensions A and B is A> B (in FIG. 8 (c), the relationship between the dimensions B and C is B = C). .. The relationship between dimensions A and C is A> C, that is, the width of the end portion on the extending direction side along the second direction of the opening pattern B (dimension C), and the minimum opening width of the opening pattern A (dimension A). ) Narrower. The end portion on the extending direction side is an end portion on the extending direction side, and an end portion on the side separated from the coupling position of the opening pattern A and the opening pattern B. As a result, silicon can be left in the groove formed corresponding to the opening pattern B. As a result, the mechanical strength of the wiring layer portion in the upper region 7 of the first liquid flow path can be improved.

Further, in order to increase the inclination angle of the lower silicon 8 of the wiring layer (the angle formed by the lower surface of the wiring layer and the lower surface of the groove made of the lower silicon of the wiring layer) and make it easier for bubbles in the liquid to escape, the relationship between the dimensions B and C is set. It is preferable that B> C. That is, the width (dimension C) of the end portion on the extending direction side along the second direction of the opening pattern B (the end portion on the side separated from the joint position between the opening pattern A and the opening pattern B) is set to the other end. It is made smaller than the width (dimension B) of the portion (the end portion on the bonding position side). As a result, the silicon thickness F in the groove becomes thicker, and the inclination angle of the silicon 8 under the wiring layer also increases accordingly. As a result, air bubbles in the liquid are easily removed. FIG. 7 shows an example of the structure of the first flow path formed by using the mask having such a dimensional relationship (B> C).

The dimensions A to D can be set, for example, in the following range. The dimension A is preferably in the range of 100 μm to 300 μm, and more preferably in the range of 150 μm to 250 μm. The dimension B is preferably in the range of 40 μm to 80 μm, and more preferably in the range of 50 μm to 70 μm. The dimension C can be set to the same size as the dimension B, or can be set smaller than the dimension B. In that case, the dimension C is preferably 20 μm or less, more preferably 10 μm or less. The dimension D (the length of the opening pattern B in the extending direction) is preferably in the range of 300 μm to 500 μm, and more preferably in the range of 350 μm to 450 μm. The dimension E (thickness of the silicon substrate 3) is preferably in the range of 500 μm to 700 μm, and more preferably in the range of 550 μm to 650 μm. The thickness of the wiring layer 1 is preferably in the range of 5 μm to 15 μm, and more preferably in the range of 8 μm to 12 μm.

The dimensional ratio can be set as follows, for example. The dimension E / dimension A (aspect ratio), which is a dimension ratio, is preferably in the range of 2/1 to 4/1, and more preferably in the range of 2.5 / 1 to 3.5 / 1. The dimension C / dimension A is preferably in the range of 1/10 or less, and more preferably 1/20 or less. The dimension D / dimension A is preferably in the range of 3/1 to 1/1, and more preferably in the range of 2.5 / 1 to 1.5 / 1. The dimension F / dimension E is preferably in the range of 10/600 to 30/600, and more preferably in the range of 15/600 to 25/600.

The pattern spacing between the opening patterns B (distance between adjacent sides) and (the widest pattern spacing between the adjacent opening patterns B when the relationship between the dimensions B and the dimension C is B> C) are 10 μm to 30 μm. It is preferably in the range of 15 μm to 25 μm, and more preferably in the range of 15 μm to 25 μm.

The opening area of the opening pattern A (opening pattern corresponding to the second flow path) is SA, and the opening area of the opening pattern B (all of the plurality of opening patterns corresponding to the grooves leaving silicon) is SB. At this time, the opening area ratio SB / SA is preferably in the range of 1.0 / 1 to 1.4 / 1, and more preferably in the range of 1.1 / 1 to 1.3 / 1.

The plurality of grooves corresponding to the opening pattern B (recesses in the concave-convex pattern region of the mask) are not limited to one side of the opening pattern A as shown in FIGS. 4A and 4B. For example, as shown in FIGS. 5A and 5B, they may be provided on both sides of the opening pattern A so as to face each other. Note that FIG. 5A is a schematic plan view of the side (silicon substrate side) opposite to the side where the wiring layer of the liquid discharge substrate is located. FIG. 5B is a schematic cross-sectional view taken along the line aa'of FIG. 5A.

The second liquid flow path 13 formed in the wiring layer 1 which is a communication portion between the first liquid flow path 4 and the pressure generating chamber 5 may be one continuous opening. For example, as shown in FIG. 6A, it may be formed so as to extend continuously along the arrangement direction of the pressure generating elements 2 (in FIG. 6A, a long rectangular opening is formed). Further, as shown in FIG. 6B, the second liquid flow path 13 may be individually formed so as to correspond to each pressure generating element 2 (in FIG. 6B, a plurality of rectangular openings). Is an array). The mask described above has an opening pattern A including a region corresponding to a region forming such a second liquid flow path. By reactive ion etching the back surface of the silicon substrate through such a mask, the groove formed on the silicon substrate corresponding to the opening pattern A includes the region forming the second liquid flow path. It is formed. This groove communicates with the second liquid flow path when forming the second liquid flow path (through port) in the wiring layer. As a result, a first liquid flow path including a groove communicating with the second liquid flow path can be formed. This second liquid flow path serves as a supply port for the liquid to the pressure generating chamber 5.

The contour line of the mask pattern including the opening (opening pattern B) of the uneven pattern region is not limited to a straight line, but may include a curved line.

7 (a) and (b) and FIGS. 7 (c) and 7 (d) show other embodiments (concavities and convexities) corresponding to FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b), respectively. Another example of the planar shape of the part) is shown. FIG. 7A is a schematic plan view of the side (silicon substrate side) opposite to the side where the wiring layer of the liquid discharge substrate is located. FIG. 7B is a schematic cross-sectional view taken along the line aa'of FIG. 7A. FIG. 7 (c) shows a modified example of FIG. 7 (a), and is a schematic plan view of a side (silicon substrate side) opposite to the side where the wiring layer of the liquid discharge substrate is located. FIG. 7D is a schematic cross-sectional view taken along the line aa'of FIG. 7C.
In the dimension of the etching mask shown in FIG. 8 (c), by setting the dimension C to 0 and maximizing the dimension B (increasing until it is adjacent to the adjacent opening), the thickness F at the end of the groove is the thickness F. Can be thickened, and the mechanical strength of the silicon 8 under the wiring layer can be improved. Further, the inclination angle of the silicon 8 under the wiring layer becomes high, so that bubbles in the liquid can be easily removed.

Here, the reactive ion etching in the present invention is not particularly limited, and can be applied to all reactive ion etching (RIE) generally used as anisotropic dry etching. Examples of the RIE include CCP-RIE (capacitively coupled plasma-reactive ion etching), ICP-RIE (inductive coupled plasma-reactive ion etching), and NLD-RIE (magnetic neutral loop discharge-reactive ion etching). Among these, ICP-RIE is preferable. In particular, in the case of ICP-RIE, since it is a high-density plasma, the process gas can be efficiently decomposed, and the effect that a high rate can be easily obtained can be obtained. Further, a Bosch process may be applied in which etching gas (for example, SF ₆ ) and depot gas (for example, C ₄ F ₈ ) are alternately introduced and etching is performed while forming a protective film by depo gas on the side wall.

After forming the liquid discharge substrate according to the manufacturing method described above, a nozzle plate is formed on the obtained liquid discharge substrate so as to cover the second liquid flow path and the pressure generating element. Then, the liquid discharge head can be manufactured by communicating the discharge port provided on the nozzle plate with the second liquid flow path to form a pressure generation chamber in which the pressure generating element is arranged. .. For example, a nozzle plate member 20 having the same structure as that shown in FIGS. 1 and 2 is provided on the liquid discharge substrate obtained by the manufacturing method according to the embodiment of the present invention, and a discharge port is directly above the pressure generating element 2. By forming No. 6, a liquid discharge head can be manufactured. For example, a nozzle plate member can be provided by forming a second liquid flow path, processing a resin film (for example, a polyimide film) with a laser, and bonding the resin film with an adhesive. Further, the nozzle plate member can also be provided by a method using a flow path type material.

As the pressure generating element, for example, an energy generating element (electric heat conversion element) using a heat generation resistance layer can be used. The wiring layer includes wiring (eg, aluminum) that supplies power to this pressure generating element.

The liquid ejection substrate according to the present invention can be applied to an inkjet recording head, and can also be applied to a liquid ejection head for biochip manufacturing and electronic circuit printing. Examples of the liquid discharge head include a head for manufacturing a color filter and the like in addition to the inkjet recording head.

(Example 1)
With reference to FIG. 8, a method for manufacturing the liquid discharge substrate according to the present embodiment will be specifically described.
8 (a), (b), (d) and (f) are schematic cross-sectional views corresponding to FIGS. 3 (a) and 4 (b). FIG. 8 (c) is a schematic plan view of the state shown in FIG. 8 (b) as viewed from the etching mask 10 side. FIG. 8 (e) is a schematic plan view of the silicon substrate in the state shown in FIG. 8 (d) as viewed from the back surface side (the side on which the etching mask was formed). FIG. 8 (g) is a schematic plan view seen from the etching mask 12 side in the state shown in FIG. 8 (f).

First, as shown in FIG. 8A, a silicon substrate 3 on which the wiring layer 1 including the pressure generating element 2 was formed was prepared.

Next, as shown in FIGS. 8 (b) and 8 (c), an etching mask 10 for forming the first liquid flow path is placed on the silicon substrate on the side opposite to the side on which the wiring layer 1 is formed. Formed. Specifically, the etching mask 10 was formed as follows.

A positive resist was applied to a surface (the back surface of the silicon substrate) opposite to the side on which the wiring layer 1 of the silicon substrate was formed, and exposed to a pattern corresponding to the opening pattern of the etching mask 10 shown in FIG. 8 (c). Subsequently, development was performed to form an etching mask 10. The etching mask 10 shown in FIG. 8 (c) has a pattern composed of an opening pattern A (31) and an opening pattern B (32), and the pattern dimensions thereof are 300 μm for A, 61 μm for B and C, and 500 μm for D. And said.

Next, the first liquid flow path 4 was formed on the silicon substrate 3 by performing reactive ion etching from the surface side on which the etching mask 10 was formed. Subsequently, the etching mask 10 (positive rest after development) was removed. As a result, as shown in FIGS. 8 (d) and 8 (e), a first liquid flow path 4 composed of a groove corresponding to the opening pattern A (31) and a groove corresponding to the opening pattern B (32) was formed. .. The bottom surface of the groove corresponding to the opening pattern B (32) includes a portion 11 communicating with a second liquid flow path to be formed later.

Next, a positive resist is applied onto the wiring layer 1, exposed to a pattern corresponding to the planar shape of the second liquid flow path, and subsequently developed, and the etching mask 12 shown in FIGS. 8 (f) and 8 (g) is used. Was formed.

Next, reactive ion etching was performed from the surface side on which the etching mask 12 was formed to form a second liquid flow path 13 including a through port penetrating the wiring layer 1. Subsequently, the etching mask 12 (positive resist after development) was removed.

In this way, the liquid discharge substrate shown in FIGS. 3 (a) and 4 (b) was manufactured. The depth E to the communication portion (lower surface of the wiring layer) with the second liquid flow path is 419 μm, and the silicon in the groove (groove corresponding to the opening pattern B) constituting the first liquid flow path (silicon under the wiring layer). The thickness F near the wall in 8) was 119 μm.

The manufactured liquid discharge substrate was confirmed with an electron microscope. As a result, even in the structure in which the wiring layer 1 is arranged on the upper part of the first liquid flow path 4, cracks and distortions of the wiring layer portion directly above the first liquid flow path (upper region 7) are observed. There wasn't. In addition, the chip size for forming the liquid discharge substrate could be reduced. Further, the formation region of the first liquid flow path is expanded, and an inclined structure is formed at the bottom of the groove (above the lower surface of the wiring layer) constituting the widened flow path portion (flow path portion corresponding to the opening pattern B). did it. With this structure, even if the opening area of the second liquid flow path 13 is reduced, the ink flow resistance toward the second liquid flow path 13 is low, and liquid ejection capable of high-speed printing with good defoaming properties in the liquid is possible. I was able to manufacture a substrate for use.

(Example 2)
A method for manufacturing a substrate for a liquid discharge head according to another embodiment of the present invention will be specifically described with reference to FIGS. 7 and 8.

In this example, 61 μm of the dimension C of the etching mask 10 for forming the first liquid flow path shown in FIG. 8C in Example 1 is set to 0 μm, and the dimension B is set to 100 μm. Except for this, a liquid discharge substrate was manufactured in the same manner as in Example 1.

As a result, a liquid discharge substrate having the structures shown in FIGS. 7 (a) and 7 (b) was manufactured. The depth corresponding to the depth E in FIG. 4 (b) was 419 μm, and the thickness corresponding to the thickness F in FIG. 4 (b) was 300 μm. In the second embodiment, the mechanical strength of the wiring layer can be improved by increasing the thickness F near the wall of the silicon (silicon 8 below the wiring layer) in the groove constituting the first liquid flow path. Further, it was possible to manufacture a substrate for a liquid discharge head in which the inclination angle of the silicon 8 under the wiring layer is high and bubbles in the liquid can easily escape.

The manufactured liquid discharge substrate was confirmed with an electron microscope. As a result, even in the structure in which the wiring layer 1 is arranged on the upper part of the first liquid flow path 4, cracks and distortions of the wiring layer portion directly above the first liquid flow path (upper region 7) are observed. There wasn't. In addition, the chip size for forming the liquid discharge substrate could be reduced. Further, the formation region of the first liquid flow path was widened, and an inclined structure could be formed at the bottom of the groove constituting the widened flow path portion. With this structure, even if the opening area of the second liquid flow path 13 is reduced, the ink flow resistance toward the second liquid flow path 13 is low, and liquid ejection capable of high-speed printing with good defoaming properties in the liquid is possible. I was able to manufacture a substrate for use.

1 Wiring layer 2 Pressure generating element 3 Silicon substrate 4 First liquid flow path 5 Pressure generating chamber 6 Discharge port 7 Upper area of the first liquid flow path 8 Lower silicon of the wiring layer 9 Opening of the mask of the first liquid flow path Groove corresponding to pattern B (recess) 10 Etching mask for forming the first liquid flow path 11 A portion where the first liquid flow path and the second liquid flow path communicate with each other (a portion where the second liquid flow path is formed) )
12 Etching mask for forming the second liquid flow path 13 Second liquid flow path 20 Nozzle plate member 31 Aperture pattern A
32 Aperture pattern B

Claims (7)

With a silicon substrate
A wiring layer provided on the silicon substrate and including a plurality of pressure generating elements for discharging liquid and wiring for supplying electric power to the plurality of pressure generating elements.
A first liquid flow path including a groove provided by processing the silicon substrate under the wiring layer, and
A second liquid flow path that communicates with the first liquid flow path and penetrates the wiring layer.
It is a method of manufacturing a liquid discharge substrate having
The process of providing the wiring layer on the silicon substrate and
A step of forming the first liquid flow path by performing reactive ion etching from the surface of the silicon substrate on the side opposite to the side on which the wiring layer is provided via a mask.
A step of forming the second liquid flow path communicating with the first liquid flow path in the wiring layer, and a step of forming the second liquid flow path.
Including
The mask
A first opening pattern region including a region corresponding to a region forming the second liquid flow path of the wiring layer and including an opening pattern A extending in the first direction.
A second opening pattern region comprising an opening pattern B coupled to the opening pattern A and extending in a second direction intersecting the first direction.
The opening pattern B has a portion having an opening width narrower than the minimum opening width of the opening pattern A at the end portion on the extending direction side in the second direction.
The opening pattern A is formed at a position that does not overlap with the plurality of pressure generating elements when viewed from the first direction and the direction orthogonal to the second direction.
When viewed from the direction orthogonal to the first direction and the second direction, the opening pattern B has the plurality of pressure generating elements arranged at positions that do not overlap with the plurality of pressure generating elements. It is formed so as to extend from the opening pattern A toward the opposite side to the existing side.
The plurality of pressure generating elements are arranged along the first direction.
A method for manufacturing a liquid ejection substrate, which comprises leaving silicon of the silicon substrate at the bottom of a groove formed corresponding to the opening pattern B when reactive ion etching is performed via the mask. With a silicon substrate
A wiring layer provided on the silicon substrate and including a plurality of pressure generating elements for discharging liquid and wiring for supplying electric power to the plurality of pressure generating elements.
A first liquid flow path including a groove provided by processing the silicon substrate under the wiring layer, and
A second liquid flow path that communicates with the first liquid flow path and penetrates the wiring layer.
It is a method of manufacturing a liquid discharge substrate having
The process of providing the wiring layer on the silicon substrate and
A step of forming the first liquid flow path by performing reactive ion etching from the surface of the silicon substrate on the side opposite to the side on which the wiring layer is provided via a mask.
A step of forming the second liquid flow path communicating with the first liquid flow path in the wiring layer, and a step of forming the second liquid flow path.
Including
The mask
A first opening pattern region including a region corresponding to a region forming the second liquid flow path of the wiring layer and including an opening pattern A extending in the first direction.
A second opening pattern region comprising an opening pattern B coupled to the opening pattern A and extending in a second direction intersecting the first direction.
The opening pattern B has a portion having an opening width narrower than the minimum opening width of the opening pattern A at the end portion on the extending direction side in the second direction.
The liquid discharge substrate has a plurality of the pressure generating elements arranged along the first direction in the wiring layer.
The second opening pattern region includes a plurality of the opening patterns B, and each of the plurality of opening patterns B has an end portion in each region corresponding to a region forming the plurality of pressure generating elements in the wiring layer. Placed towards
A method for manufacturing a liquid ejection substrate, which comprises leaving silicon of the silicon substrate at the bottom of a groove formed corresponding to the opening pattern B when reactive ion etching is performed via the mask. With a silicon substrate
A wiring layer provided on the silicon substrate and including a plurality of pressure generating elements for discharging liquid and wiring for supplying electric power to the plurality of pressure generating elements.
A first liquid flow path including a groove provided by processing the silicon substrate under the wiring layer, and
A second liquid flow path that communicates with the first liquid flow path and penetrates the wiring layer.
It is a method of manufacturing a liquid discharge substrate having
The process of providing the wiring layer on the silicon substrate and
A step of forming the first liquid flow path by performing reactive ion etching from the surface of the silicon substrate on the side opposite to the side on which the wiring layer is provided via a mask.
A step of forming the second liquid flow path communicating with the first liquid flow path in the wiring layer, and a step of forming the second liquid flow path.
Including
The mask
A first opening pattern region including a region corresponding to a region forming the second liquid flow path of the wiring layer and including an opening pattern A extending in the first direction.
A second opening pattern region comprising an opening pattern B coupled to the opening pattern A and extending in a second direction intersecting the first direction.
The opening pattern B has a portion having an opening width narrower than the minimum opening width of the opening pattern A at the end portion on the extending direction side in the second direction.
The liquid discharge substrate has a plurality of the second liquid flow paths arranged along the first direction in the wiring layer.
The opening pattern A of the mask is a band-shaped opening pattern including all the regions corresponding to the regions forming the plurality of second liquid flow paths in the wiring layer.
The second opening pattern region includes a plurality of the opening patterns B, and each of the plurality of opening patterns B corresponds to a region corresponding to a region forming the plurality of second liquid flow paths in the wiring layer. Arranged with the ends facing,
A method for manufacturing a liquid ejection substrate, which comprises leaving silicon of the silicon substrate at the bottom of a groove formed corresponding to the opening pattern B when reactive ion etching is performed via the mask. When reactive ion etching is performed via the mask, silicon having an inclined structure that becomes thinner as it is closer to the second liquid flow path is left at the bottom of the groove formed corresponding to the opening pattern B. The method for manufacturing a liquid discharge substrate according to any one of claims 1 to 3 . The method for manufacturing a liquid discharge substrate according to any one of claims 1 to 4 , wherein the opening pattern B is rectangular. The method for manufacturing a liquid discharge substrate according to any one of claims 1 to 4 , wherein the opening width of the opening pattern B narrows as the distance from the coupling position between the opening pattern A and the opening pattern B increases. The step of forming a liquid discharge substrate according to the method for manufacturing a liquid discharge substrate according to any one of claims 1 to 6, and the second liquid flow path and the pressure generation on the liquid discharge substrate. It has a step of forming a nozzle plate so as to cover the element, and communicates with a discharge port provided in the nozzle plate and the second liquid flow path to form a pressure generating chamber in which the pressure generating element is arranged. A method for manufacturing a liquid discharge head.

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