Liquid discharge head

Abstract

To provide a liquid discharge head which uses a substrate conjugant where multiple substrates are joined.SOLUTION: A liquid discharge head having multiple discharge ports arranged is provided. The liquid discharge head comprises: a first substrate which has an energy generation element on one surface, and has a first supply port penetrating from the one surface to the other surface; a second substrate which is joined to the first substrate through an adhesive agent in a lamination direction, has a second supply port communicating with the first supply port, the second supply port penetrating from the surface to be joined of the second substrate to the other surface. The first supply port has a first opening on the surface to be joined. The second supply port has a second opening on the surface to be joined. In at least one direction out of an arrangement direction of the discharge port and an orthogonal direction orthogonal to the arrangement direction of the discharge port, when a width of the first opening is defined as W1 and a width of the second opening is defined as W2, W1>W2 is satisfied in the liquid discharge head.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a liquid ejection head that uses a substrate assembly in which a plurality of substrates are bonded together. [Background technology]

[0002] Many MEMS (Micro Electro Mechanical Systems) devices are manufactured by bonding substrates together, one example of which is a liquid ejection head that ejects liquid.

[0003] An example of a liquid ejection head is an inkjet recording head. An inkjet recording head has an energy generating element that provides energy for ejecting ink. An ejection port forming member is formed on the surface of the substrate, and ejection ports for ejecting ink are opened in the ejection port forming member. A through hole is also formed in the substrate, and ink is supplied from the rear side of the substrate to the front side through the through hole. The through hole functions as an ink flow path through which the ink flows.

[0004] Inkjet recording heads are generally manufactured using adhesive bonding technology, in which substrates are bonded together using an adhesive such as resin. When the adhesive is crushed during bonding, it moves into the ink flow path as excess adhesive. This excess adhesive can clog the ink flow path. If the ink flow path becomes blocked, ink will not flow, which is problematic as it can cause ejection defects.

[0005] Patent Document 1 proposes that when bonding silicon substrates on which ink flow paths have been processed, a slit is provided on the bonding surface of the partition between the pressurized liquid chambers and the amount of excess adhesive is reduced by absorbing the excess adhesive into this slit. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP2004-249668 Public Relations Summary of the Invention [Problem to be solved by the invention]

[0007] If slits are provided as in Patent Document 1, there is a concern that the strength of the partition wall will decrease, causing the partition wall to crack during the manufacturing process. In addition, the need to secure space for providing slits in the partition wall makes it difficult to reduce the width of the partition wall, making it difficult to improve performance by increasing the density of the pressure chambers and to reduce costs by reducing the chip size.

[0008] The present disclosure has been made in consideration of the above-mentioned problems, and has an objective to provide a liquid ejection head having a substrate assembly that can prevent clogging of ink flow paths due to excess adhesive generated during bonding, without providing structures such as slits on the bonding surfaces of partition walls between flow paths.

[0009] A further object of the present invention is to provide a liquid ejection head having a substrate assembly capable of increasing the bonding strength between the substrates by the adhesive. [Means for solving the problem]

[0010] One example of the present disclosure is a liquid ejection head having a plurality of ejection ports arranged therein, the liquid ejection head comprising: a first substrate having an energy generating element on one surface thereof and a first supply port penetrating from the one surface to the other surface thereof; and a second substrate bonded to the first substrate in a stacking direction via an adhesive, the second supply port having a second supply port communicating with the first supply port, the second supply port penetrating from the joined surface of the second substrate to the other surface thereof, the first supply port having a first opening on the joined surface thereof and the second supply port having a second opening on the joined surface thereof, wherein W1 is a width of the first opening and W2 is a width of the second opening in at least one direction of the arrangement direction of the ejection ports and a direction perpendicular to the arrangement direction of the ejection ports, and W1>W2. Effect of the Invention

[0011] It is possible to provide a liquid ejection head having a substrate assembly that can prevent clogging of ink flow paths due to excess adhesive generated during bonding without providing structures such as slits on the bonding surfaces of the partition walls between the flow paths. [Brief description of the drawings]

[0012] [Figure 1] 5A to 5C are cross-sectional views illustrating a method for manufacturing the liquid ejection head according to the first embodiment of the present disclosure. [Diagram 2] FIG. 11 is a plan view showing the positional relationship of openings in a joint portion. [Diagram 3] FIG. 2 is a cross-sectional view showing the first embodiment and a comparative example. [Figure 4] 11 is a cross-sectional view showing the positional relationship of the moved adhesive. FIG. [Diagram 5] FIG. 11 is a plan view showing the positional relationship of openings in a joint portion. [Figure 6] FIG. 4 is a cross-sectional view showing the adhesive during bonding. [Figure 7] 11A to 11C are plan views showing examples of the shape of a second opening. [Figure 8] 5A to 5C are cross-sectional views illustrating a method for manufacturing a liquid ejection head according to a second embodiment of the present disclosure. [Figure 9] 11A to 11C are cross-sectional views showing a modified example of the method for manufacturing the first substrate in the second embodiment of the present disclosure. [Figure 10] FIG. 11 is a cross-sectional view showing an example of processing of a first supply port in the second embodiment of the present disclosure. [Figure 11] 10A to 10C are cross-sectional views showing an example of a manufacturing method for a first supply port and a third supply port in a second embodiment of the present disclosure. [Figure 12] 11 is a bird's-eye view of an example of a liquid ejection head according to a second embodiment of the present disclosure. [Figure 13] 1A is a plan view of an example of a liquid ejection head according to the present disclosure, and FIG. 1B is a plan view of a second substrate bonded to the liquid ejection head according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an example of an embodiment of the present disclosure will be described with reference to the drawings. However, the following description does not limit the scope of the present disclosure. As an example, the present embodiment employs a thermal method of discharging liquid by generating bubbles using a heating element, but the present disclosure can also be applied to liquid discharge heads employing a piezo method or various other liquid discharge methods.

[0014] In addition, in this disclosure, the X-axis, Y-axis, and Z-axis are appropriately used as directional axes for explaining the structure of the liquid ejection head. The X-axis and Y-axis are mutually orthogonal on a horizontal plane to form a liquid ejection surface. The long axis of the liquid ejection head extends in the Y-axis direction, and the recording medium moves in the X-axis direction. The Z-axis is a vertical axis orthogonal to the X-axis and Y-axis, and is the direction in which the first substrate 131 and the second substrate 132 are stacked, as described later.

[0015] First Embodiment Fig. 1 shows a cross-sectional view of a method for manufacturing a liquid ejection head according to this embodiment. Fig. 1(A-1) and Fig. 1(A-2) show a method for processing a first substrate 131. A first substrate 131 having a circuit and an energy generating element (e.g., heater) 107 formed on a first surface 141 is prepared (Fig. 1(A-1)). A second surface 142 of the first substrate 131, located on the opposite side of the first surface 141, becomes a bonding surface with a second substrate 132, as described below.

[0016] Silicon is suitable for the first substrate 131 because it is necessary to form semiconductor elements such as transistors that constitute the circuit. The second surface 142 (back surface) of the first substrate 131 is thinned to a desired thickness. If not necessary, the thinning process can be omitted. Next, the second surface 142 of the first substrate 131 is smoothed. Methods include grinding, dry polishing, and polishing by CMP (Chemical Mechanical Polishing).

[0017] Next, a first supply port 112 is processed in the first substrate 131 as shown in FIG. 1(A-2). In this embodiment, the first supply port 112 opens as a through groove penetrating to the second surface 142. The opening of the first supply port 112 in the second surface 142 is defined as a first opening 151. The perimeter of the opening is defined as the perimeter of the first opening 151. The shape of the first supply port 112 may be, for example, a groove shape extending in the longitudinal direction. Processing techniques include chemical dry etching, chemical wet etching, laser, sandblasting, and the like.

[0018] 1(B-1) and 1(B-2) show a method for processing the second substrate 132. The second substrate 132 is prepared (FIG. 1(B-1)). Silicon or resin materials can be used for the second substrate 132, but a silicon substrate is preferable because it is stronger than resin materials and stable against liquids. The side of the second substrate 132 that will be bonded is designated as the third surface 143, and the opposite surface is designated as the fourth surface 144.

[0019] A second supply port 113 is processed in the second substrate 132 (FIG. 1(B-2)). The processing method is the same as that for the first supply port 112. The second supply port 113 is composed of a large number of through holes that are smaller than the first supply port 112 and penetrate from the third surface 143 to the fourth surface 144.

[0020] The opening of the second supply port 113 formed in the third surface 143 is defined as a second opening 152. The perimeter thereof is defined as the perimeter of the second opening 152.

[0021] 1(C) to (E) show the assembly of a liquid ejection head having a first substrate 131 and a second substrate 132. An adhesive 121 is provided on a second surface 142 of the first substrate 131 (FIG. 1(C)). A material that has high adhesion to the substrate is recommended for the adhesive 121. In terms of application, a material that is less likely to be contaminated with air bubbles is also preferable, and a low-viscosity material that makes it easy to reduce the thickness of the adhesive 121 is also preferable. Examples of materials include epoxy resin, acrylic resin, silicone resin, benzocyclobutene resin, polyamide resin, polyimide resin, and urethane resin.

[0022] The first substrate 131 and the second substrate 132 coated with the adhesive 121 are aligned by an alignment device so that the second substrate 132 is the bottom layer along the direction of gravity. Next, the aligned substrate stack is clamped and temporarily fixed by a clamping mechanism or the like. Next, the temporarily fixed substrate stack is transferred to a bonding device. After the substrate stack is heated to a predetermined temperature in the bonding device, it is bonded by applying pressure for a predetermined time and pressure. These bonding parameters are appropriately set according to the adhesive material. Furthermore, bonding in a vacuum is preferable in order to prevent air bubbles from being mixed into the joint.

[0023] If the adhesive 121 is a thermosetting type, it may be heated in a bonding device until it hardens, or the substrate bonded body may be taken out after bonding and heated in a separate oven or the like to harden it.

[0024] When the adhesive is completely cured, the first supply port 112 and the second supply port 113 communicate with each other to form a flow path 115 penetrating the substrate assembly (FIG. 1(D)). In this embodiment, one first supply port 112 communicates with a plurality of second supply ports 113. The perimeter of the first opening 151 is larger than the perimeter of the second opening 152.

[0025] Fig. 2(A) shows a plan view illustrating a suitable positional relationship between the first opening 151 and the second opening 152. This shows the first opening 151 and the second opening 152 when the substrate bonded body is viewed from the first surface 141 side in Fig. 1(D).

[0026] In this embodiment, a plurality of second openings 152 are arranged in the longitudinal direction (Y direction) of the first opening 151. The perimeter of the second opening is smaller than the perimeter of the first opening 151. The length of the first opening 151 in the lateral direction (X direction) is W 1X The length of the second opening 152 in the short direction (X direction) is W 2X Similarly, the length of the first opening 151 in the longitudinal direction (Y direction) is W 1Y The length of the second opening 152 in the longitudinal direction (Y direction) is W 2Y Let us assume that.

[0027] In Figure 2(A), the short side is W 1X >W 2X And the longitudinal direction is also W 1Y >W 2Y In this embodiment, the first opening 151 and the second opening 152 are not limited to the X and Y directions, and the width of the opening satisfies the relationship W1>W2 in any direction of 360°, which is preferable. As will be described later, in the case of such a structure, the adhesive runs up toward the first supply port 112 side (Z direction) as shown in FIG. 1(D).

[0028] Next, a discharge port forming member is formed on the first surface 142 side of the substrate assembly. A dry film resist, which is a film base material coated with a photocurable resin, is laminated onto the first surface 141 of the substrate assembly. Thereafter, the wall 118 of the discharge port forming member is patterned by exposure and development. Next, a top plate 119 of the discharge port forming member is formed on the wall 118 in a similar manner. For example, a dry film resist is laminated, exposed, and developed to form a top plate 119 having discharge ports 101, and the liquid discharge head is completed (FIG. 1(E)).

[0029] In this embodiment, the first substrate 131 is a substrate having, on a first surface 141, the energy generating elements 107, the ejection port forming members 118 and 119 having the ejection port 101, and a driving IC. Therefore, the first supply port 112 has a function of supplying liquid to the energy generating elements 107. The liquid heated by the energy generating elements 107 is ejected from the ejection port 101. The first substrate 131 can function as a liquid ejection head substrate.

[0030] 2(A), the first supply port 112 has a large groove shape and extends in the longitudinal direction (Y direction). In order to increase the supply speed of liquid to the multiple ejection ports and heater elements present in the first surface 141, it is preferable that the volume of the first supply port 112 is large.

[0031] The second substrate 132 is provided with a second supply port 113, which functions to converge the liquid flow paths of the first supply port 112 in the planar direction and further connect to a fourth supply port formed in a base member existing below the fourth surface 144 of the second substrate 132. The width of the fourth supply port and the adjacent supply port pitch are larger than those of the first supply port 112.

[0032] As shown in FIG. 2(A), a plurality of second supply ports 113 communicate inside the first opening 151 of the first supply port 112. The second supply port 113 is a through hole with a smaller volume than the first supply port 112, and the perimeter of the second opening 152 is also shorter than the perimeter of the first opening 151. The cross section of the second opening 152 in the substrate assembly is as shown in FIG. 1(E). The second substrate 132 functions as a pitch conversion member for the liquid supply port with respect to the first substrate 131 (liquid ejection head substrate).

[0033] FIG. 2(B) is a modified example of the present embodiment, showing a substrate assembly in which the width W1 of the first opening 151 and the width W2 of the second opening 152 have a relationship of W1 < W2 in some directions. Similar to FIG. 2(A), the large groove-shaped first supply port 112 and the plurality of small through-hole second supply ports 113 communicate with each other.

[0034] However, in this modified example, there is a direction in which the perimeter of the first opening is smaller than the perimeter of the second opening. In this modified example, in the longitudinal direction (Y direction), W 1y >W 2y holds, but in the short side direction (X direction), W 1X <W 2X holds. Therefore, the adhesive extruded from the joint portion in the short side direction may be unfavorable as described later.

[0035] The second supply port 113 once converges the liquid from the large groove-shaped first supply port 112 and communicates with a plurality of fourth supply ports (not shown) existing below FIG. 1(E). Each of the plurality of second supply ports 113 can select the fourth supply port to be connected.

[0036] For example, when circulating a liquid, the supply ports upstream or downstream of the discharge port are connected to each other. When using inks of different types, the supply ports of the same color are connected to each other. Since the second supply port 113 is small, the desired first supply port and the fourth supply port can be separated and connected without mixing with other supply ports. Therefore, the perimeter of the second opening 152 tends to be short, and there is a problem that it is easily blocked by an adhesive.

[0037] Therefore, it is effective in preventing blockage to make it difficult for the adhesive 121 to move to the second supply port 113. On the other hand, excess adhesive that has moved due to joining is generated around the joint. In the present embodiment, depending on the positional relationship between the opening of the first supply port 112 and the opening of the second supply port 113, the movement of the excess adhesive can be controlled, making it difficult for the adhesive to move to the second supply port 113.

[0038] Fig. 3 shows the relationship between the assumed positions of the openings and the assumed movement of the adhesive 121. The cases are classified according to the magnitude relationship between the width W1 of the first opening 151 and the width W2 of the second opening 152.

[0039] Fig. 3(A) shows the case where W1 > W2. The adhesive 121 is extruded from the joint surface and climbs up to the side of the first supply port 112 (in the positive Z direction). Fig. 3(B) shows the case where W1 = W2. The adhesive 121 that has moved from the side surface of the joint surface climbs up and down the side surfaces of the first supply port 112 and the second supply port 113.

[0040] Furthermore, Fig. 3(C) shows the case where W1 < W2. In this case, when the adhesive 121 has moved to the first opening 151, the horizontal movement stops due to surface tension. Then, the adhesive 121 will flow down to the side wall side (negative Z direction) of the second supply port 113.

[0041] 3(B) and 3(C) are both comparative examples in which the adhesive 121 runs down toward the second supply port 113 (negative Z direction), which may cause clogging. In contrast, in FIG. 3(A), W1>W2, and when the adhesive 121 reaches the second opening 152, the adhesive 121 stops moving in the horizontal direction due to surface tension, and the adhesive 121 runs up toward the side wall of the first supply port 112. In this case, the adhesive 121 is less likely to enter the second supply port 113, which is preferable as an embodiment of the present disclosure.

[0042] Next, a more preferable example will be described when W1>W2 is satisfied. Fig. 4 shows a cross-sectional view of a joint between first substrate 131 and second substrate 132 after the adhesive has been cured. In terms of adhesion, the case where adhesive 121 reaches second opening 152 as shown in Fig. 4(A) is more preferable than the case where adhesive 121 does not reach second opening 152 as shown in Fig. 4(B).

[0043] This is because, after the adhesive 121 reaches the opening, the excess adhesive 121 runs up the side wall of the first supply port 112 due to surface tension. The adhesive 121 that runs up the side wall of the first supply port runs thinner and over a wider range than in the case of Fig. 4(B). Therefore, compared to the case where the adhesive 121 does not run up (Fig. 4(B)), the contact area between the adhesive 121 and the first substrate 131 increases, and the adhesive strength improves.

[0044] From the viewpoint of improving the adhesion, it is preferable to increase the number of second supply ports 113. Fig. 5 shows an example of the arrangement of first openings 151 and second openings 152. In Fig. 5(B), only one second supply port 113 for each first supply port 112 communicates with the first supply port 112. In comparison with this case, as shown in Fig. 5(A), it is preferable to arrange a large number of second supply ports 113 and increase the total length A of the portion where adhesive 121 is in contact with second openings 152, because the area of ​​adhesive 121 creeping up the side wall of first supply port 112 increases proportionally.

[0045] Moreover, it is preferable to uniformly arrange the second supply ports 113 (i.e., the second openings 152) over the entire longitudinal direction of the first supply port 112 (i.e., the first opening 151), since the entire first supply port 112 can be uniformly adhered to the surface. For example, as shown in FIG. 5(C), the adhesion of the entire first supply port 112 can be increased by arranging the second openings 152 near the ends of the first opening 151 and near the center of the first opening 151. Therefore, it is preferable to arrange three or more second supply ports 113 for one first supply port 112.

[0046] The conditions for the adhesive 121 to reach the second opening 152 will be described. Fig. 6(A) shows a cross-sectional view of the first substrate 131 before bonding, in which the adhesive 121 is applied to the second surface of the partition wall 153. The adhesive volume V per unit length in the depth direction (Y direction) corresponds to the area of ​​the adhesive 121 in Fig. 6(A).

[0047] If the adhesive 121 is crushed and moved after bonding, the adhesive 121 advances the same distance in the X direction and the Z direction from the bonded portion due to surface tension, and forms adhesive reservoir portions 154 shown with an isosceles triangular cross section on both sides of the partition wall 153. As shown in Fig. 6(B) , if all of the adhesive 121 has moved, the width L of the adhesive reservoir portion 154 is expressed by the following formula (1) using the adhesive volume V. L 2 =V (1)

[0048] In order for adhesive 121 to flow along second substrate 132 and reach second opening 152, it is necessary that width 1 from first opening 151 (end of partition wall) and distance d to the end of second opening 152 are at least equal to or less than L. Therefore, the condition for adhesive 121 to reach second opening 152 is that the following formula (2) must be satisfied. d≦(V) 0.5 (2)

[0049] For example, when the adhesive volume V is simply expressed as adhesive thickness T × partition wall width S as shown in FIG. 6(A), formula (2) becomes formula (3). d≦(T×S) 0.5 (3)

[0050] When the center of the second aperture is placed at the center of the first aperture, equation (3) becomes equation (4). W1-W2≦2×(T×S) 0.5 (4)

[0051] Therefore, in order for adhesive 121 to reach second opening 152, distance d from the end of second opening 152 to the end of first opening 151 needs to be set to be equal to or less than the distance expressed by equations (2) to (4).

[0052] Furthermore, the adhesive volume V can be measured from the bonded substrates. For example, when the first supply ports 112 are arranged in the short-side direction (X direction), the area of ​​the adhesive portion when the cross section of the bonded portion is exposed in the short-side direction and the cross section of the partition wall 153 between the first supply ports 112 is observed corresponds to the adhesive volume V.

[0053] An example of a typical cross section is shown in Figure 6(C). The adhesive is crushed, and part of it remains on the bonding surface, while the rest moves to both sides of the partition wall 153. The adhesive 121 that was originally on the partition wall 153 is deformed into the shape of dot region B after bonding. Therefore, the area of ​​this dot region B corresponds to the adhesive volume V. Methods for exposing the cross section include various dicing methods, FIB, and CMP. Also, observation methods include SEM and TEM.

[0054] A preferred shape of second supply port 113 will now be described. Fig. 7 shows a plan view of second opening 152 present in the third surface. Fig. 7(A) shows a rectangle, which is a typical shape. In a rectangle such as Fig. 7(A), capillary force is likely to act from the four vertices (corners) into second supply port 113, making it easy for adhesive 121 to flow.

[0055] Therefore, as shown in Figures 7(B)(C)(D)(E), the corners with vertices are eliminated and replaced with arcs, making it difficult for capillary force to act on the adhesive 121, thereby preventing the adhesive 121 from penetrating into the second supply port 113.

[0056] FIG. 7(B) shows an ellipse, and FIG. 7(C) shows an oval shape composed of a semicircle and a rectangle. FIG. 7(D) shows a rectangle with only the corners being arcs, and FIG. 7(E) shows a circle. Also, in an octagon as in FIG. 7(F), the vertices of each octagon have a larger angle than a rectangle, so the capillary force is weakened and the adhesive 121 is less likely to penetrate into the second supply port 113 than in FIG. 7(A), which is preferable. If the number of vertices is increased to 5 or more, not limited to an octagon, and the vertices are made obtuse, the adhesive 121 can be prevented from penetrating more than in FIG. 7(A). In this way, by preventing the adhesive 121 from moving to the second supply port 113, the adhesive 121 can be made to run up the side wall of the first supply port.

[0057] 3(A), the deeper the depth Z1 of the first supply port 112, the more preferable it is, because a larger amount of adhesive 121 can be held by the side wall of the first supply port. It is preferable to design the depth Z1 of the first supply port 112 to be deeper than at least the depth Z2 of the second supply port 113. In particular, when the total thickness of the bonded substrates is determined, it is preferable to make the first supply port 112 as deep as possible.

[0058] Second Embodiment As described in embodiment 1, when adhesive 121 is caused to flow up the side wall of the first supply port, depending on the amount of adhesive 121, adhesive 121 may reach first surface 141 and even the energy generating elements present on first surface 141, which may degrade the discharge performance.

[0059] Therefore, in this embodiment, an example in which the first supply port 112 has an overhanging shape will be described. Figure 8 shows cross-sectional views of a method for manufacturing a liquid ejection head according to this embodiment.

[0060] 8(A-1) and 8(A-2) show a method for processing a first substrate 131. A first substrate 131 having a circuit and an energy generating element (e.g., heater) 107 formed on a first surface 141 is prepared (FIG. 8(A-1)), and a supply port is processed in the first substrate 131. At this time, the first supply port 112 shown in the first embodiment is replaced by one consisting of a first supply port 112 and a third supply port 114 as shown in FIG. 8(A-2).

[0061] First supply port 112 is processed from second surface 142 to partway through first substrate 131, and third supply port 114 communicates with the surface (upper surface) of first supply port 112 opposite second surface 142. An opening formed in the upper surface of first supply port 112 is defined as third opening 158. Since the width in the X direction of third supply port 114 is narrower than that of first supply port 112 (i.e., the opening area of ​​third opening 158 is smaller than the opening area of ​​first opening 151), the upper surface of first supply port 112 becomes overhang portion 155.

[0062] The first supply port 112 may be processed first from the second surface 142 and stopped in the first substrate 131, and then the third supply port 114 may be processed from the first surface 141 to communicate with the first supply port 112. Alternatively, after the first supply port 112 is formed, the narrow third supply port 114 may be processed so as to penetrate to the first surface 141.

[0063] There are a number of methods available for processing the first supply port 112. Examples of the method include chemical dry etching, chemical wet etching, laser, sandblasting, and cutting.

[0064] After completing the processing of the first substrate 131, the second substrate 132 is processed to have a second supply port 113 in the same manner as in the first embodiment (FIGS. 8(B-1) and 8(B-2)), and is bonded to the first substrate 131 (FIGS. 8(C) and 8(D)). After the bonding adhesive is cured, a discharge port forming member is formed on the first surface 141, and the liquid discharge head is completed (FIG. 8(E)).

[0065] 8(D), the adhesive 121 that has flowed up the side surface of the first supply port 112 can be stopped at the upper surface (overhanging portion 155) of the first supply port 112. By stopping the adhesive 121 at the overhanging portion 155, the adhesive 121 is less likely to reach the third supply port 114 or the first surface 141 beyond the third supply port, and therefore deterioration of the energy generating elements 107 on the first surface 141 due to the adhesive 121 is suppressed.

[0066] 9(A-1) to 9(A-3), an SOI substrate may be used as the first substrate 131. In this case, the first supply port 112 may be processed from the second surface 142 to the oxide film 157 of the SOI substrate, the third supply port 114 may be processed from the first surface 141, and finally the oxide film 157 may be removed to form the overhang portion 155.

[0067] 9(B-1) and 9(B-2), a membrane film 156 made of an oxide film, a resin film, or a multilayer film thereof may be formed on the first surface 141 of the first substrate 131, and an overhang portion 155 may be formed. For example, the first substrate 131 may be processed up to the membrane film 156, and the third supply port 114 may be processed in the membrane film 156 to form the overhang portion 155. The membrane film 156 is set to a film configuration that can maintain sufficient strength and rigidity even if the substrate portion supporting the membrane film 156 is lost.

[0068] A more preferable shape of the first supply port 112 is to curve the overhang surface that is the upper surface of the first supply port 112. Fig. 10(A) shows a cross-sectional view of the first substrate 131 processed by a general manufacturing method. Fig. 10(C) shows a bird's-eye view of region C (near overhang portion 155) of the cross section of the first substrate 131 shown in Fig. 10(A).

[0069] As shown in Figure 10(C), overhang surface 161 is ideally machined as a flat surface, but in the flat surface, the angle that overhang surface 161 makes with the other surface of the supply port is a right angle. In Figure 10(C), the other surface is first supply port side surface 162, and there is a ridgeline 163 where first supply port side surface 162 and overhang surface 161 intersect. Ridge line 163 extends in the Y direction (longitudinal direction of the supply port). The angle between the two surfaces that make up the ridgeline is a right angle (the angle at point E in Figure 10(C)).

[0070] In such a ridgeline having a right-angled cross section, if the adhesive 121 runs up to the ridgeline 163, the adhesive 121 tends to move along the ridgeline 163 due to capillary force. The adhesive 121 tends to gather at the ridgeline 163, and tends to spread over the entire ridgeline 163.

[0071] If a large amount of adhesive 121 gathers on ridge line 163, adhesive 121 also moves toward overhang surface 161 in the X direction, and ends up reaching third supply port 114. As a result, problems may occur in which the third supply port is blocked or the adhesive 121 travels up the side surface thereof to reach first surface 141.

[0072] As a countermeasure to this, it is preferable to process the overhanging portion 155 so as to curve it, as shown in Fig. 10(B). Fig. 10(D) shows a bird's-eye view of region D in Fig. 10(B). Overhanging surface 161 is curved, and the end portions are closer to the second surface 142 side than the center portions.

[0073] As a result, the angle formed by the intersection of overhang surface 161 and first supply port side surface 162 becomes obtuse. Furthermore, because overhang surface 161 curves and connects to first supply port side surface 162, the corner at the connection portion (point E in FIG. 10(D)) disappears. As a result, in FIG. 10(D), adhesive 121 is less likely to move along ridge line 163 due to capillary force and disperses, making it more difficult for adhesive 121 to reach third supply port 114.

[0074] An effective method for curving the overhanging surface at the bottom of the first supply port 112 is to process it by silicon dry etching and stop the etching in the silicon substrate to form the first supply port 112.

[0075] The manufacturing flow diagram is shown in Figure 11. A first substrate 131 is prepared, with circuits and energy generating elements (e.g., heaters) 107 formed on a first surface 141 (Figure 11(A)). In Figure 11(B), a first supply port 112 is processed from a second surface 142 of the first substrate 131 by dry etching, and the etching is stopped midway through the substrate. Thereafter, a third supply port 114 is processed (Figure 11(C)). The third supply port 114 may be processed by any method.

[0076] In the processing of Fig. 11(B), the silicon substrate is etched by dry etching using etchant gases such as SF6, Cl2, CF4, etc., which are radicalized and ionized. Since the density of the etchant gas is high at the center of the first supply port 112, the central portion of the overhang surface 161 tends to be deep and the outer periphery tends to be shallow. As a result, the overhang surface 161 can be curved as shown in Figs. 11(B) and (C).

[0077] Even in the case of dry etching, if the overhang portion 155 serves as an etching stop layer as shown in Figures 9(A) and (B), the overhang portion 155 is not curved. Also, if wet etching, which is another method, is used in the processing of Figure 11(B), the etchant molecules enter the first supply port 112 uniformly, so that the overhang portion 155 is also unlikely to be curved.

[0078] It is preferable that third opening 158 has a shape that makes it difficult for adhesive 121 to penetrate if it creeps up overhanging portion 155. The preferable shape of second opening 152 can similarly prevent the penetration of adhesive 121. Specifically, the shapes of Figures 7(B) to (F) are preferable.

[0079] 12 shows a bird's-eye view of an example of a liquid ejection head produced in this embodiment. A first substrate 131 functions as a substrate that ejects liquid. A second substrate 132 functions as a substrate that changes the pitch of the liquid supply port.

[0080] The second substrate 132 communicates the first supply ports 112 arranged at a narrow pitch with a fourth supply port (not shown) of the base member (present below the second substrate 132) via a fine second supply port 113. The fourth supply port is configured to have a width wider than the first supply ports 112 or a wider adjacent pitch, so that the first supply ports 112, which are arranged at a narrow pitch, are converted into fourth supply ports, which are arranged at a wider pitch.

[0081] The liquid circulates along the arrow indicated by F in Fig. 12. The adjacent first supply ports each function as an inlet and an outlet for the liquid, and prevent the liquid from sticking at the discharge port 101 located between them. The circulating liquid passes through the second supply port 113 and moves to the fourth supply port (not shown).

[0082] Fig. 13(A) shows a plan view of the liquid ejection head of Fig. 12, and Fig. 13(B) shows an example of a plan view of the second substrate 132 thereof. In the liquid ejection head, a plurality of first supply ports 112 are arranged, and second supply ports 113 are arranged in the longitudinal direction of the first supply ports 112. As shown in Fig. 13(B), the shape of the second opening 152 is an ellipse. Three or four second supply ports 113 are connected to one first supply port 112, and are arranged almost uniformly across the center and ends of the first supply port 112. The width W1 of the first supply port 112 and the width W2 of the second supply port 113 satisfy W1>W2.

[0083] <<Other embodiments>> The present disclosure includes configurations typified by the following recording apparatus example and recording apparatus control method example.

[0084] (Configuration 1) A liquid ejection head having a plurality of ejection ports arranged therein, a first substrate having an energy generating element on one surface thereof and a first supply port penetrating from the one surface to the other surface thereof; a second substrate bonded to the first substrate in a stacking direction via an adhesive, the second substrate having a second supply port communicating with the first supply port, the second supply port penetrating from the bonded surface of the second substrate to the other surface; the first supply port has a first opening on the joining surface, and the second supply port has a second opening on the joining surface; A liquid ejection head, characterized in that, when the width of the first opening is W1 and the width of the second opening is W2 in at least one direction selected from the direction of arrangement of the ejection ports and a direction perpendicular to the direction of arrangement of the ejection ports, W1>W2. (Configuration 2) 2. The liquid ejection head according to configuration 1, wherein the first substrate has an ejection port forming member provided on a surface having the energy generating elements, and the ejection ports are formed. (Configuration 3) A liquid ejection head as described in configuration 1 or 2, further comprising a base member having a fourth supply port that is wider or has a wider spacing between adjacent supply ports than the first supply port, the base member being joined to the second substrate, and the second substrate communicating the first supply port with the fourth supply port via the second supply port. (Configuration 4) A liquid ejection head described in any one of configurations 1 to 3, characterized in that a stagnation portion of the adhesive is continuously formed from the joint portion of the second substrate to the second opening, and the stagnation portion of the adhesive is in contact with the second opening. (Configuration 5) the first supply port extends in a direction in which the ejection ports are arranged, and is arranged via a partition wall in a direction perpendicular to the direction in which the ejection ports are arranged, A liquid ejection head according to any one of configurations 1 to 4, characterized in that the following formula is satisfied when the volume per unit length of the adhesive pressed by the partition during the bonding in the arrangement direction of the ejection ports is V and the distance between the partition and the adjacent second opening is d. d ≦ (V) 0.5 (Configuration 6) The width of the first opening in the arrangement direction of the ejection ports is W 1x The width of the first opening in a direction perpendicular to the arrangement direction of the ejection ports is W 1y , the width of the second opening in the arrangement direction of the ejection ports is W 2x、 The width of the second opening in a direction perpendicular to the arrangement direction of the ejection ports is W 2y Then, W 1x >W 2x , and W 1y >W 2y 6. The liquid ejection head according to any one of configurations 1 to 5, wherein: (Configuration 7) 7. The liquid ejection head according to any one of configurations 1 to 6, wherein the maximum thickness of the first substrate is greater than the maximum thickness of the second substrate. (Configuration 8) A liquid ejection head described in any one of configurations 1 to 7, characterized in that in the first supply port, an opening area of ​​a third opening formed on a side of the first substrate having the energy generating element is smaller than an opening area of ​​the first opening. (Configuration 9) 9. The liquid ejection head according to configuration 8, wherein the first supply port has a curved portion between the third opening and the partition wall. (Configuration 10) 10. The liquid ejection head according to any one of configurations 1 to 9, wherein the shape of the second opening is selected from a figure including at least a partial circular arc, or a polygon having pentagons or more sides. (Configuration 11) 9. The liquid ejection head according to configuration 8, wherein the shape of the third opening is selected from a figure including at least a part of a circular arc, or a polygon having pentagons or more sides. (Configuration 12) The liquid ejection head of configuration 1, characterized in that the first supply ports extend in the arrangement direction of the ejection ports and are arranged via partitions in a direction perpendicular to the arrangement direction of the ejection ports, and the second supply ports are arranged in a number of three or more for each first supply port along the arrangement direction of the ejection ports. [Explanation of symbols]

[0085] 101 Discharge port 103 Membrane layer 107 Energy generating element 112 First Supply Inlet 113 Second Supply Inlet 114 Third Supply Inlet 115 Flow Path 118 Wall of discharge port forming member 119 Top plate of discharge port forming member 121 Adhesive 131 First Board 132 Second Board 141 First Side 142 The Second Side 143 The Third Side 144 The Fourth Side 151 First Opening 152 Second Opening 153 Bulkhead 154 Adhesive retention section 155 Overhang 156 Membrane 157 Oxide Film 158 Third Aperture 161 Overhanging Surface 162 First supply port side 163 The ridge where the overhang surface and the first supply port side intersect

Claims

1. A liquid ejection head having a plurality of ejection ports arranged therein, a first substrate having an energy generating element on one surface thereof and a first supply port penetrating from the one surface to the other surface thereof; a second substrate bonded to the first substrate in a stacking direction via an adhesive, the second substrate having a second supply port communicating with the first supply port, the second supply port penetrating from the bonded surface of the second substrate to the other surface; the first supply port has a first opening on the joining surface, and the second supply port has a second opening on the joining surface; The width of the first opening in at least one direction between the arrangement direction of the ejection ports and a direction perpendicular to the arrangement direction of the ejection ports is defined as W 1 and the width of the second opening is W 2 Then, W 1 >W 2 A liquid ejection head comprising:

2. 2. The liquid ejection head according to claim 1, wherein the first substrate has an ejection port forming member provided on a surface having the energy generating elements, and the ejection ports are formed.

3. A liquid ejection head as described in claim 1, further comprising a base member having a fourth supply port which is wider or has a larger spacing between adjacent supply ports than the first supply port, the base member being joined to the second substrate, and the second substrate communicating the first supply port with the fourth supply port via the second supply port.

4. A liquid ejection head as described in claim 1, characterized in that a stagnation portion of the adhesive is continuously formed from the joint portion of the second substrate to the second opening, and the stagnation portion of the adhesive is in contact with the second opening.

5. the first supply port extends in a direction in which the ejection ports are arranged, and is arranged via a partition wall in a direction perpendicular to the direction in which the ejection ports are arranged, A liquid ejection head as described in claim 1, characterized in that the following formula is satisfied when the volume per unit length of the adhesive pressed by the partition during the bonding in the arrangement direction of the ejection ports is V and the distance between the partition and the adjacent second opening is d. d ≦ (V) 0.5

6. The width of the first opening in the arrangement direction of the ejection ports is W 1x , the width of the first opening in a direction perpendicular to the arrangement direction of the ejection ports is W 1y , the width of the second opening in the arrangement direction of the ejection ports is W 2x、 The width of the second opening in a direction perpendicular to the arrangement direction of the ejection ports is W 2y Then, W 1x >W 2x , and W 1y >W 2y 2. The liquid ejection head according to claim 1,

7. 2. The liquid ejection head according to claim 1, wherein the maximum thickness of the first substrate is greater than the maximum thickness of the second substrate.

8. A liquid ejection head as described in claim 5, characterized in that the opening area of ​​a third opening formed on the side of the first substrate having the energy generating element in the first supply port is smaller than the opening area of ​​the first opening.

9. 9. The liquid ejection head according to claim 8, wherein the first supply port has a curved portion between the third opening and the partition wall.

10. 2. The liquid ejection head according to claim 1, wherein the shape of the second opening is selected from a figure including at least a part of a circular arc, or a polygon having pentagons or more sides.

11. 9. The liquid ejection head according to claim 8, wherein the shape of the third opening is selected from a figure including at least a part of a circular arc, or a polygon having pentagons or more sides.

12. The liquid ejection head according to claim 1, characterized in that the first supply ports extend in the arrangement direction of the ejection ports and are arranged via a partition in a direction perpendicular to the arrangement direction of the ejection ports, and the second supply ports are arranged in a number of three or more for each first supply port along the arrangement direction of the ejection ports.

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