Head substrate and liquid ejection head with head substrate, and method of manufacturing liquid ejection head

Abstract

To provide a head substrate in which scratches or chips hardly occur in an edge part of an ejection port surface.SOLUTION: A head substrate 2 includes: a liquid ejection substrate 4 including an ejection port surface 603 in which ejection ports 602 each ejecting liquid are formed and a back surface 701 opposite to the ejection port surface 603; and a liquid supply substrate 5 which is bonded to the back surface 701 of the liquid ejection substrate 4 and supplies the liquid to the liquid ejection substrate 4. The back surface 701 includes an electrode terminal 704 adjacent to the liquid supply substrate 5 in a first direction X. At least one of the liquid ejection substrate 4 and the liquid supply substrate 5 includes at least one protruding portion 503 located on a side opposite to the electrode terminal 704 in the first direction X, and the at least one protruding portion 503 more protrudes in the first direction X than the ejection port surface 603.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a head substrate, a liquid ejection head including the head substrate, and a method for manufacturing a liquid ejection head. [Background technology]

[0002] A liquid ejection head generally has a head substrate equipped with ejection ports for ejecting liquid and electrode terminals. The electrode terminals are electrically connected to an electrical wiring board. For reasons of appearance and function, it is preferable to prevent damage such as scratches and chips to the ejection port surface formed with the ejection ports during manufacturing. For this reason, as described in Patent Document 1, a jig that does not come into contact with the ejection port surface is sometimes used during the manufacturing of a liquid ejection head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-307710 Summary of the Invention [Problem to be solved by the invention]

[0004] When electrically connecting the electrode terminals to the electrical wiring board, the head substrate is sometimes positioned so that the electrode terminals face upward, and the head substrate is then temporarily fixed by abutting it against a jig. In this case, depending on the configuration of the head substrate, the ejection port surface may face downward, causing the edge of the ejection port surface to come into contact with the jig, potentially resulting in scratches or chips on the edge of the ejection port surface. In Patent Document 1, the ejection port surface faces upward, so it is possible to separate the ejection port surface from the jig, but this method is difficult in a configuration in which the ejection port surface faces downward.

[0005] An object of the present invention is to provide a head substrate that is less susceptible to scratches or chips on the edge of the ejection port surface. [Means for solving the problem]

[0006] A head substrate according to one aspect of the present invention includes a liquid ejection substrate having an ejection port surface on which ejection ports for ejecting liquid are formed and a back surface of the ejection port surface, and a liquid supply substrate bonded to the back surface of the liquid ejection substrate and supplying liquid to the liquid ejection substrate. The back surface has electrode terminals adjacent to the liquid supply substrate in a first direction. At least one of the liquid ejection substrate and the liquid supply substrate has at least one protruding portion located on the opposite side of the electrode terminal in the first direction, and the at least one protruding portion protrudes in the first direction beyond the ejection port surface. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a head substrate in which scratches and chips are less likely to occur on the edge of the ejection port surface. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view of a liquid ejection head according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of a head substrate of the liquid ejection head shown in FIG. [Figure 3] FIG. 2 is a perspective view of a head substrate of the liquid ejection head shown in FIG. [Figure 4] 2 is a schematic flow of a manufacturing process for the liquid ejection head shown in FIG. [Figure 5] FIG. 1 is a schematic diagram showing a wafer structure on which a plurality of head substrates are formed. [Figure 6] FIG. 1 is a schematic diagram showing a separation process. [Figure 7] 1A to 1C are schematic diagrams showing a jig used in a temporary fixing step and a temporary fixing procedure. [Figure 8] 1A to 1C are schematic diagrams showing a jig used in a temporary fixing step and a temporary fixing procedure. [Figure 9] 1A to 1C are schematic diagrams illustrating an electrical connection step and a sealing material application step. [Figure 10] FIG. 10 is a cross-sectional view of a head substrate of a liquid ejection head of a comparative example. [Figure 11] FIG. 10 is a cross-sectional view showing a state in which the head substrate is tilted relative to the jig. [Figure 12] FIG. 10 is a plan view of a head substrate of a liquid ejection head according to a second embodiment. [Figure 13] 10A and 10B are a cross-sectional view and a plan view of a head substrate of a liquid ejection head according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Several embodiments of the present invention will be described below with reference to the drawings. The embodiments described below do not limit the scope of the present invention. Although this embodiment is directed to a head substrate of a liquid ejection head that ejects ink, the present invention can also be applied to head substrates that eject liquids other than ink. In the following description, the first direction X is a direction perpendicular to the long axis of the head substrate, or the direction in which the head substrate and the electrical wiring board are joined, and the second direction Y is a direction parallel to the long axis of the head substrate, or the direction in which multiple electrode terminals on the head substrate are arranged. The first direction X and the second direction Y are perpendicular to each other.

[0010] (First embodiment) Fig. 1 is a perspective view of a liquid ejection head according to a first embodiment of the present invention, Fig. 2(a) is a cross-sectional view of a head substrate of the liquid ejection head according to the first embodiment, and Fig. 2(b) is an enlarged view of part A in Fig. 2(a). Fig. 3(a) is a perspective view of the head substrate as viewed from the liquid ejection substrate side, and Fig. 3(b) is a perspective view of the head substrate as viewed from the liquid supply substrate side. As shown in Fig. 1, the liquid ejection head 1 has a head substrate 2 and an electrical wiring substrate 3 connected to the head substrate 2. The head substrate 2 is formed mainly from silicon.

[0011] (Head board 2) As shown in FIG. 3, the head substrate 2 is a generally rectangular plate-like body, and has a first side surface 203 and a second side surface 204 that are parallel to the second direction Y. As shown in FIG. 2, the head substrate 2 has a liquid ejection substrate 4 that ejects liquid, and a liquid supply substrate 5 that supplies liquid to the liquid ejection substrate 4. The liquid ejection substrate 4 is bonded to the liquid supply substrate 5. The liquid supply substrate 5 is formed with a liquid supply port 501 (see FIG. 1) that supplies liquid, and a liquid supply path 502 (see FIG. 3(b)) that communicates with the liquid supply port 501. The liquid ejection substrate 4 has a plurality of ejection paths 601 that communicate with the liquid supply path 502 of the liquid supply substrate 5. The openings of the ejection paths 601 form ejection ports 602. The liquid ejection substrate 4 has an ejection port surface 603 with a plurality of ejection ports 602, and a back surface 701 of the ejection port surface 603, and the liquid supply substrate 5 is bonded to the back surface 701 of the liquid ejection substrate 4. On the opposite side of the electrode terminal 704 (described later) in the first direction X, the liquid supply substrate 5 has at least one (one in this embodiment) protruding portion 503 that protrudes in the first direction X beyond the ejection port surface 603. The function and effect of the protruding portion 503 will be described later.

[0012] The liquid ejection substrate 4 includes an ejection port forming substrate 6 and an element substrate 7. The ejection port forming substrate 6, element substrate 7, and liquid supply substrate 5 are stacked, with the element substrate 7 being located between the ejection port forming substrate 6 and the liquid supply substrate 5. The ejection port forming substrate 6 includes an ejection path 601, an ejection port 602, and an ejection port surface 603. The element substrate 7 includes an energy generating element 703 that generates energy for ejecting liquid from the ejection path 601, and an electrode terminal 704 electrically connected to the energy generating element 703. The electrode terminal 704 supplies power and signals for driving the energy generating element 703 from the liquid ejection device main body (not shown) via the electrical wiring substrate 3. The element substrate 7 and the ejection port forming substrate 6 form pressure chambers 705, and the energy generating elements 703 transmit ejection pressure to the liquid in the pressure chambers 705. The liquid pressurized by the energy generating element 703 is ejected as droplets from the ejection ports 602 to the outside and forms an image by landing on a medium such as paper.

[0013] The energy generating element 703 is a piezoelectric element that operates the pressure chambers 705 as actuators that selectively apply ejection pressure to the liquid. A liquid ejection head 1 using a piezoelectric element has the same number of pressure chambers 705 as the ejection paths 601, and a piezoelectric element is attached to each pressure chamber 705. To densely arrange the ejection paths 601 without changing the dimensions of the head substrate 2, it is necessary to increase the number of piezoelectric elements, which in turn increases the number of electrode terminals 704. Increasing the number of electrode terminals 704 also increases the size of the electrical wiring board 3 electrically connected to the electrode terminals 704. Therefore, in this embodiment, an end region 702 adjacent to the liquid supply substrate 5 in the first direction X is provided on the back surface 701 of the liquid ejection substrate 4 (element substrate 7), and the electrode terminals 704 are provided in the end region 702. The energy generating element 703 is not limited to a piezoelectric element and may be an electrothermal transducer. The electrothermal transducer applies heat to the liquid to generate bubbles, which then eject the liquid from the ejection ports 602.

[0014] (Electrical wiring board 3) The electrical wiring board 3 is a thin, flat member that is flexible, and is formed, for example, by providing a conductor pattern of copper or the like on a polyimide film. Examples of the electrical wiring board 3 include FPC (Flexible Printed Circuits) and TAB (Tape Automated Bonding) tape. One longitudinal end of the electrical wiring board 3 is formed with a lead portion 301 that connects to the electrode terminal 704 of the head substrate 2, and the other end is provided with an external signal input terminal 302 (see FIG. 1) that is electrically connected to the liquid ejection device main body. The lead portion 301 and the external signal input terminal 302 are electrically connected by a conductor pattern (not shown) inside the electrical wiring board 3.

[0015] As shown in FIG. 1, the electrical wiring board 3 is electrically connected to the head substrate 2 such that the side 303 on which the lead portions 301 are arranged is parallel to the side 706 on which the electrode terminals 704 of the head substrate 2 are arranged. As shown in FIG. 2, the electrode terminals 704 of the head substrate 2 and the corresponding lead portions 301 of the electrical wiring board 3 are electrically connected by wire bonding using an electrical connection member 801 such as a conductor wire. The conductor wire may be mainly composed of, for example, gold, copper, aluminum, or silver, or an alloy containing two or more of these. The electrical connection method is not limited to wire bonding, and bump bonding, lead terminals, NCP (Non-Conductive Paste), ACF (Anisotropic Conductive Film), etc. may also be used. Electrical signals are transmitted from the liquid ejection device main body to the electrical wiring board 3 via the external signal input terminal 302 and then to the energy generating elements 703 of the head substrate 2 via the electrode terminals 704. The electrode terminals 704 of the head substrate 2, the lead portions 301 of the electrical wiring board 3, and the electrical connection members 801 constitute the electrical connection portion 8.

[0016] The electrical connection parts 8 are entirely sealed and protected by a sealing material 9. The sealing material 9 has the rigidity to ensure the bonding strength between the head substrate 2 and the electrical wiring board 3 and to protect the electrical connection parts 8 from external forces. It is preferable that the sealing material 9 has the function of suppressing corrosion of the electrical connection parts 8 due to the ejected liquid or moisture in the environment. For this reason, a material such as epoxy resin is preferably used for the sealing material 9, but other materials can be used as appropriate depending on the performance required of the sealing material 9.

[0017] (Method of manufacturing liquid ejection head 1) 4 shows an outline of the steps in a method for manufacturing the liquid ejection head 1. The method for manufacturing the liquid ejection head 1 includes a wafer step S1, a separation step S2, a temporary fixing step S3, an electrical connection step S4, a sealant application step S5, and a curing step S6. These steps will be described with reference to FIGS. 4 to 10.

[0018] (Wafer process S1) First, multiple head substrates 2 are created in wafer process S1. Fig. 5(a) is a partial perspective view of multiple wafer-form head substrates 2, and Fig. 5(b) is a cross-sectional view taken along line BB in Fig. 5(a). As shown in Fig. 5(a), multiple wafer-form head substrates 2 are arranged in parallel. As shown in Fig. 5(b), the wafer-form head substrate 2 is a laminate of a wafer-form liquid supply substrate 5, a wafer-form ejection port formation substrate 6, and a wafer-form element substrate 7. To create the wafer-form head substrate 2, the wafer-form ejection port formation substrate 6, the wafer-form element substrate 7, and the wafer-form liquid supply substrate 5 are laminated together and bonded together using an adhesive, adhesive film, or the like.

[0019] The element substrate 7 and liquid supply substrate 5 of the head substrate 2, the liquid supply substrate 5 of another head substrate 2 adjacent to it in the first direction X, and waste material 201 (see FIG. 6) present between the two liquid supply substrates 5 form a hollow portion 202. A recess corresponding to the hollow portion 202 is formed in advance in the liquid supply substrate 5, and electrode terminals 704 are formed in advance in an end region 702 of the element substrate 7 that faces the recess. By joining the liquid supply substrate 5 and the element substrate 7, the hollow portion 202 having the electrode terminals 704 is formed.

[0020] (Separation process S2) In the separation step S2, the wafer is cut by stealth dicing to cut out individual head substrates 2 from the wafer. FIG. 6 is a cross-sectional view showing the separation step S2 along line BB in FIG. 5(a), where FIG. 6(a) is a schematic diagram showing the laser light irradiation method, and FIG. 6(b) is a schematic diagram showing the expanding step. First, dicing tape 10 is attached to the back surface 505 of the liquid supply substrate 5, which is the surface to be bonded to the liquid ejection substrate 4. As shown in FIG. 6(a), laser light 12 is irradiated through the dicing tape 10 along cutting line L1 of the liquid supply substrate 5 to form a modified region with low crystal strength. Next, laser light 12 is irradiated from the ejection port formation substrate 6 side along cutting line L2 that straddles the ejection port formation substrate 6 and the element substrate 7 to form a modified region. At this time, the modified region is formed in a positional relationship such that cutting line L1 is closer to the electrode terminal 704 than cutting line L2.

[0021] Next, as shown in FIG. 6(b), the dicing tape 10 is pulled with a predetermined force F. The wafer is divided starting from the modified region, and the head substrates 2 are separated and individualized. The electrode terminals 704 of the element substrate 7 are exposed. The waste material 201 that formed the hollow portion 202 remains held by the dicing tape 10. As a result, as shown in FIG. 2, at least one (one in this embodiment) protruding portion 503 is formed on the head substrate 2, located on the opposite side of the electrode terminals 704 in the first direction X. The separation step S2 may be performed by blade dicing instead of stealth dicing.

[0022] (Temporary fixing process S3) In the temporary fixing process S3, the cut-out head substrate 2 is temporarily fixed to a jig 11. Figure 7 shows the jig 11 used in the temporary fixing process S3 and the procedure for temporary fixing. In the temporary fixing process S3, a jig 11 having a groove 111 as shown in Figure 7(a) is used. As shown in Figure 7(b), the head substrate 2 is fitted into the groove 111 of the jig 11, and as shown in Figure 7(c), the head substrate 2 is temporarily fixed to the jig 11 using a presser 112. In this embodiment, a jig 11 capable of manufacturing two liquid ejection heads 1 is used, but the number of liquid ejection heads 1 to be manufactured and the shape of the jig 11 are not limited.

[0023] The temporary fixing step S3 will be described in more detail with reference to FIG. 8. FIG. 8(a) is an enlarged view of part C in FIG. 7(a), FIG. 8(b) is an enlarged view of part D in FIG. 7(b), and FIG. 8(c) is an enlarged view showing the state in which the electrical wiring board 3 is temporarily fixed to the jig 11 in FIG. 8(b). FIG. 8(d) is a cross-sectional view taken along line DD in FIG. 8(c), showing the state in which the head substrate 2 and the electrical wiring board 3 are temporarily fixed to the jig 11. The jig 11 is made of a heat-resistant and corrosion-resistant metal such as stainless steel or aluminum, and has two abutment reference portions 113 and a groove 111. First, as shown in FIGS. 8(a) and 8(b), the first side surface 203 of the head substrate 2 is pressed against the abutment reference portion 113 of the jig 11, and the head substrate 2 is positioned in the groove 111 and temporarily fixed. At this time, only the protruding portion 503 abuts against the abutment reference portion 113, as shown in FIG. 8(d). The height of the abutment reference portion 113 is lower than the height of the head substrate 2, which can prevent damage due to scratches or chips on the edge of the rear surface 505 of the liquid supply substrate 5. The head substrate 2 can be temporarily fixed to the jig 11 by a method of fixing it with a weight positioned relative to the jig 11, a method of fixing it with the pressing force of a spring member provided on the jig 11, a method of fixing it by suction from a suction hole provided on the jig 11, or the like (not shown).

[0024] 8(c) and 8(d), the electric wiring board 3 is positioned in the first direction X so that the lead portions 301 are in positions that allow electrical connection with the corresponding electrode terminals 704, and is temporarily fixed to the jig 11. The electric wiring board 3 can be temporarily fixed to the jig 11 using the same fixing method as for the head substrate 2 described above, or by using an adhesive sheet or adhesive tape (not shown).

[0025] (Electrical connection process S4, sealant application process S5, curing process S6) The electrical connection step S4 and the sealant application step S5 will be described with reference to FIG. 9. FIG. 9 is a cross-sectional view taken along line EE in FIG. 8(c), where FIG. 9(a) is a cross-sectional view showing the head substrate 2 and the electrical wiring board 3 electrically connected by wire bonding, and FIG. 9(b) is a cross-sectional view showing the electrical connection portion 8 sealed. In the electrical connection step S4, the electrical wiring board 3 is electrically connected to the electrode terminals 704 of the temporarily fixed head substrate 2. Specifically, with the head substrate 2 and the electrical wiring board 3 temporarily fixed to a jig 11 as shown in FIG. 8(d), the electrode terminals 704 and the lead portions 301 are electrically connected by wire bonding with an electrical connection member 801 as shown in FIG. 9(a). Next, as shown in FIG. 9(b), a dispenser is used to apply sealant 9 to the entire electrical connection portion 8, including the electrode terminals 704 of the head substrate 2, the lead portions 301 of the electrical wiring board 3, and the electrical connection member 801, on the jig 11, to completely cover the electrical connection portion 8. In this state, the liquid ejection head 1 is placed in a curing oven and heated for a long time. The heat hardens the sealant 9, sealing and protecting the electrical connection parts 8 and ensuring the bonding strength between the head substrate 2 and the electrical wiring board 3. Thereafter, the liquid ejection head 1 is removed from the jig 11.

[0026] (Effects of this embodiment) FIG. 10 shows a cross-sectional view of a head substrate 200 of a comparative example. The side surface 401 of the liquid ejection substrate 4 and the side surface 506 of the liquid supply substrate 5, located opposite the electrode terminal 704 in the first direction X, are located at approximately the same position. In practice, depending on the cutting accuracy, the side surface 401 of the liquid ejection substrate 4 may protrude the most in the first direction X, or the side surface 506 of the liquid supply substrate 5 may protrude the most in the first direction X. Otherwise, the head substrate 200 has the same configuration as the head substrate 2 of this embodiment shown in FIG. 2. When this head substrate 200 is temporarily fixed to the jig 11 in accordance with the temporary fixing step S3 described above, there is a possibility that the ejection port forming substrate 6, particularly the edge 604 of the ejection port surface 603, may come into contact with the abutment reference portion 113. This makes the edge 604 of the ejection port surface 603 more susceptible to damage, such as scratches or chips. Damage to the ejection port surface 603 is not only undesirable from an appearance perspective, but is also undesirable from a functional perspective, as it is likely to damage the wiring and liquid flow paths inside the head substrate 2 and result in a decline in liquid ejection performance. Furthermore, in the sealant application step S5, the sealant 9 may creep up along the scratches or chips, adhere to the ejection port surface 603, and block the ejection ports 602.

[0027] 8(d), the first side surface 203 of the head substrate 2 in this embodiment has a protruding portion 503 that protrudes in the first direction X beyond the ejection port surface 603. In the temporary fixing step S3, only the protruding portion 503 comes into contact with the abutment reference portion 113. Because the ejection port forming substrate 6, and in particular the edge portion 604 of the ejection port surface 603, is separated from the abutment reference portion 113, damage due to scratches or chips near the edge portion 604 of the ejection port surface 603 can be suppressed. Even when the head substrate 2 is separated from the abutment reference portion 113, the ejection port forming substrate 6 is unlikely to come into contact with the abutment reference portion 113, so damage due to scratches or chips can be suppressed.

[0028] The protruding portion 503 may be provided on the element substrate 7. In this case, the element substrate 7 comes into contact with the abutment reference portion 113 on the side opposite to the electrode terminal 704 in the first direction X, and therefore the same effect can be achieved.

[0029] In this embodiment, the dimensional accuracy of the head substrate 2 in the first direction X is more important than the dimensional accuracy in the second direction Y. That is, in this embodiment, the head substrate 2 is pressed against the jig 11 in the first direction X to be temporarily fixed, and the electrical wiring board 3 is temporarily fixed in the first direction X with high accuracy. This ensures stable electrical connection by wire bonding and sealing of the electrical connection portion 8, thereby satisfying the dimensional accuracy of the liquid ejection head 1, including the electrical connection position and the shape of the sealant 9. Furthermore, the electrical wiring board 3 is connected to the head substrate 2 in the first direction X and is bent midway to be connected to the liquid ejection device main body. In this case, the sealant 9 is preferably provided closer to the head substrate 2 than the bending position of the electrical wiring board 3 so that the hardened sealant 9 does not interfere with the bending of the electrical wiring board 3. To control the position of the sealant 9, it is necessary to manage the dimensions of the head substrate 2 and the jig 11, the fixing position of the electrical wiring board 3, the positional relationship between the jig 11 and the manufacturing equipment, the application of the sealant 9, and the like, with respect to the first direction X. 10, due to variations in cutting accuracy, it is uncertain which of the liquid ejection substrate 4 and the liquid supply substrate 5 will come into contact with the abutment reference portion 113 of the jig 11. For this reason, high cutting accuracy is required for both the liquid ejection substrate 4 and the liquid supply substrate 5. In this embodiment, because the liquid supply substrate 5 comes into contact with the abutment reference portion 113 of the jig 11, it is possible to relax the cutting accuracy in the first direction X on the first side surface 203 of the liquid ejection substrate 4.

[0030] Considering the cutting accuracy of stealth dicing, it is preferable that at least one protruding portion 503 protrudes in the first direction X beyond the ejection port surface 603 by a protruding length L (FIG. 8(d)) greater than 20 μm. The thickness of the liquid ejection substrate 4 is preferably 100 μm or greater from the viewpoint of strength, and 500 μm or less from the viewpoints of productivity, cost, and miniaturization. As shown in FIG. 11 , there is a possibility that the head substrate 2 may tilt toward the electrode terminals 704 when fitting the head substrate 2 into or removing it from the groove 111 of the jig 11. Even in this case, if the protruding length L of the liquid supply substrate 5 relative to the ejection port formation substrate 6 is 20 μm or greater, the possibility of the ejection port formation substrate 6 coming into contact with the abutment reference portion 113 can be reduced even if the head substrate 2 is tilted by 2° toward the electrode terminals 704. This reduces the precision required for fitting the head substrate 2 into or removing it from the groove 111 of the jig 11.

[0031] (Second embodiment) A second embodiment of the present invention will be described with reference to FIG. 12. FIG. 12(a) is a plan view of the head substrate 2 as viewed from the liquid supply substrate 5 side, and FIG. 12(b) is a plan view of the head substrate 2 as viewed from the liquid ejection substrate 4 side. The basic configuration of the liquid ejection head 1 of this embodiment is the same as that of the first embodiment. In this embodiment, the liquid ejection head 1 can be manufactured using the same process as in the first embodiment. In this embodiment, at least one protruding portion 503 is a plurality of protruding portions 503. In other words, only a portion of the side surface of the liquid supply substrate 5 in the second direction Y protrudes in the first direction X beyond the side surface of the liquid ejection substrate 4. The protruding portion 503 is provided at a position corresponding to the abutment reference portion 113 of the jig 11. In this embodiment, too, the protruding length L of the liquid supply substrate 5 relative to the ejection port formation substrate 6 is desirably greater than 20 μm, taking into account the cutting accuracy of stealth dicing.

[0032] This embodiment achieves the same effects as the first embodiment. Furthermore, when cutting the wafer by dicing, the area of ​​the liquid supply substrate 5 that comes into contact with the abutment reference portions 113 of the jig 11 is narrowed, so the area of ​​the liquid supply substrate 5 that requires high cutting accuracy can be narrowed. In this embodiment, two protrusions 503 are provided on the liquid supply substrate 5 to correspond to the two abutment reference portions 113, but three or more protrusions 503 may be provided depending on the number and positions of the abutment reference portions 113.

[0033] (Third embodiment) A third embodiment of the present invention will be described with reference to Fig. 13. Fig. 13(a) is a cross-sectional view of the head substrate 2, and Fig. 13(b) is a plan view of the head substrate 2 viewed from the film 6B side. The basic configuration of the liquid ejection head 1 of this embodiment is the same as that of the first embodiment. In this embodiment, the liquid ejection head 1 can also be manufactured using the same process as in the first embodiment.

[0034] The liquid ejection substrate 4 includes an ejection path forming substrate 6A having an ejection path 601, a film 6B having an ejection port surface 603, and an element substrate 7. The ejection path forming substrate 6A is formed of a Si substrate and has the same configuration as the ejection port forming substrate 6 of the first and second embodiments. The film 6B is laminated on the ejection path forming substrate 6A. The film 6B is provided for electrical insulation and to adjust the thickness of the head substrate 2. The thickness of the film 6B is preferably 0.2 μm or greater. The film 6B can be formed, for example, from a laminate of an oxide film such as SiO or SiO2 and Si, a single-layer film of SiO or SiO2, or a single-layer film combining two or more materials selected from SiO, SiO2, and Si, but other materials may also be used. The film 6B can be formed only at predetermined positions using a mask in the wafer process S1, allowing for a high degree of freedom in the position where it is formed.

[0035] The bonding surface 605 of the discharge path forming substrate 6A to which the film 6B is bonded has a first peripheral edge 606 on the opposite side of the electrode terminal 704 in the first direction X, and two second peripheral edge portions 607 connected to the first peripheral edge portion 606 at a predetermined angle (perpendicular to the electrode terminal 704 in this embodiment). The film 6B is provided inside the first peripheral edge portion 606 and the two second peripheral edge portions 607. Therefore, as shown in FIG. 13(a), a step 608 is formed between the film 6B and the discharge path forming substrate 6A, and at least one of the liquid supply substrate 5, the discharge path forming substrate 6A, and the element substrate 7 forms at least one protruding portion 503 that protrudes in the first direction X beyond the discharge port surface 603.

[0036] This embodiment achieves the same effects as the first embodiment. Since either the liquid ejection substrate 4 or the liquid supply substrate 5 can protrude in the first direction X, the precision of wafer cutting can be relaxed. Furthermore, in this embodiment, the film 6B is formed in the wafer process S1, so protruding shapes can be formed not only on the long sides but also on the short sides of the head substrate 2. Because the short sides of the head substrate 2 are spaced apart from the jig 11 in the second direction Y, the head substrate 2 does not normally come into contact with the jig 11. However, for example, when removing the head substrate 2 from the jig 11, depending on the accuracy of the work process, the head substrate 2 may come into contact with the jig 11. Even in such a case, damage due to scratches or chips near the edges of the short sides of the ejection port surface 603 can be suppressed. Furthermore, in this embodiment, the position of the protruding shape can be freely set depending on the position of the abutment reference portion 113.

[0037] As explained above, in each of the above-mentioned embodiments, at least one of the liquid ejection substrate 4 and the liquid supply substrate 5 has at least one protruding portion 503 that protrudes in the first direction X beyond the ejection port surface 603. Therefore, it is possible to provide a liquid ejection head 1 in which the jig 11 is less likely to come into contact with the edge portion 604 of the ejection port surface 603 during manufacturing. The concept of the present invention can also be applied to adjusting the positional relationship between the installation location of the head substrate 2 in a manufacturing device and a reference portion of the manufacturing device.

[0038] The present invention can also be understood as follows. That is, as shown in Fig. 8(d), the head substrate 2 has a first side surface 203 having a first step 205 and a second side surface 204 having a second step 206, and the first side surface 203 and the second side surface 204 face each other in a first direction X. The head substrate 2 has an ejection port surface 603 in which ejection ports 602 for ejecting liquid are formed, and the ejection port surface 603 is connected to the first side surface 203 at a connection portion (i.e., an edge portion 604 of the ejection port surface 603). The head substrate 2 further has an electrode terminal 704 provided on a surface 701 of the second step 206 facing in the opposite direction to the ejection port surface 603. The connection portion (edge ​​portion 604 of the ejection port surface 603) between the ejection port surface 603 and the first side surface 203 is provided in a recessed portion 207 of the first step 205.

[0039] (Additional Note) This specification includes the following disclosure. [Configuration 1] a liquid ejection substrate having an ejection port surface on which ejection ports for ejecting liquid are formed and a back surface of the ejection port surface; a liquid supply substrate that is bonded to the rear surface of the liquid ejection substrate and that supplies the liquid to the liquid ejection substrate, the rear surface has an electrode terminal adjacent to the liquid supply substrate in a first direction; A head substrate, wherein at least one of the liquid ejection substrate and the liquid supply substrate has at least one protruding portion located on the opposite side of the electrode terminal in the first direction, and the at least one protruding portion protrudes in the first direction beyond the ejection port surface. [Configuration 2] 2. The head substrate according to configuration 1, wherein the protrusion is provided on the liquid supply substrate. [Configuration 3] 2. The head substrate according to configuration 1, wherein the protruding portion is provided on the liquid ejection substrate. [Configuration 4] The liquid ejection substrate is a discharge port forming substrate having the discharge port surface; an element substrate including the electrode terminals and energy generating elements electrically connected to the electrode terminals and configured to generate energy for ejecting liquid from the ejection ports; 4. The head substrate according to any one of configurations 1 to 3, comprising: [Configuration 5] The head substrate according to configuration 4, wherein the at least one protrusion protrudes beyond the ejection port surface in the first direction by a protrusion length of more than 20 μm. [Configuration 6] The head substrate according to configuration 4 or 5, wherein the at least one protrusion is a plurality of protrusions. [Configuration 7] The liquid ejection substrate is a discharge path forming substrate having a discharge path communicating with the discharge port; an element substrate including the electrode terminals and energy generating elements electrically connected to the electrode terminals and configured to generate energy for discharging liquid from the discharge paths; a membrane having the discharge port surface; 4. The head substrate according to any one of configurations 1 to 3, comprising: [Configuration 8] 8. The head substrate according to configuration 7, wherein the thickness of the film is 0.2 μm or more. [Configuration 9] the discharge path forming substrate has a bonding surface to which the film is bonded, the bonding surface having a first peripheral edge portion on the opposite side to the electrode terminal, and two second peripheral edge portions connected to the first peripheral edge portion at a predetermined angle; The head substrate according to configuration 7 or 8, wherein the film is provided inside the first peripheral edge portion and the two second peripheral edge portions. [Configuration 10] 10. The head substrate according to any one of configurations 4 to 9, wherein the energy generating element is a piezoelectric element. [Configuration 11] a first side surface having a first step; a second side surface having a second step and facing the first side surface; an ejection port surface connected to the first side surface and having an ejection port formed therein for ejecting liquid; an electrode terminal provided on a surface of the second step facing in a direction opposite to the ejection port surface; and a connection portion between the ejection port surface and the first side surface is provided in a recessed portion of the first step; [Configuration 12] The head substrate according to any one of configurations 1 to 11, an electric wiring board electrically connected to the electrode terminals of the head substrate; A liquid ejection head having: [Manufacturing method 1] a temporary fixing step of temporarily fixing, to a jig, a head substrate to which a liquid ejection substrate having an ejection port surface on which ejection ports for ejecting liquid are formed, a back surface of the ejection port surface, and electrode terminals, and a liquid supply substrate that supplies the liquid to the liquid ejection substrate are bonded; an electrical connection step of electrically connecting an electrical wiring board to the electrode terminals of the temporarily fixed head substrate, the liquid supply substrate is bonded to the rear surface of the liquid ejection substrate, the electrode terminals are provided on the rear surface and are adjacent to the liquid supply substrate in a first direction; at least one of the liquid ejection substrate and the liquid supply substrate has at least one protruding portion located on the opposite side of the electrode terminal in the first direction, and the at least one protruding portion protrudes in the first direction beyond the ejection port surface; The method for manufacturing a liquid ejection head, wherein the temporary fixing step includes abutting the at least one protruding portion against the jig. [Manufacturing method 2] The method for producing a liquid ejection head according to Production Method 1, further comprising a separation step of cutting the wafer on which the head substrates are formed by stealth dicing, and cutting out the head substrates from the wafer. [Explanation of symbols]

[0040] 2 Head board 4 Liquid discharge board 5 Liquid Supply Board 503 protruding part 603 Discharge port surface 704 Electrode terminal

Claims

1. a liquid ejection substrate having an ejection port surface on which ejection ports for ejecting liquid are formed and a back surface of the ejection port surface; a liquid supply substrate that is bonded to the rear surface of the liquid ejection substrate and that supplies the liquid to the liquid ejection substrate, the rear surface has an electrode terminal adjacent to the liquid supply substrate in a first direction; A head substrate, wherein at least one of the liquid ejection substrate and the liquid supply substrate has at least one protruding portion located on the opposite side of the electrode terminal in the first direction, and the at least one protruding portion protrudes in the first direction beyond the ejection port surface.

2. The head substrate according to claim 1 , wherein the protrusion is provided on the liquid supply substrate.

3. The head substrate according to claim 1 , wherein the protruding portion is provided on the liquid ejection substrate.

4. The liquid ejection substrate is a discharge port forming substrate having the discharge port surface; an element substrate including the electrode terminals and energy generating elements electrically connected to the electrode terminals and configured to generate energy for ejecting liquid from the ejection ports; The head substrate according to claim 1 , comprising:

5. 5. The head substrate according to claim 4, wherein the at least one protrusion protrudes beyond the ejection port surface in the first direction by a protrusion length of more than 20 [mu]m.

6. The head substrate according to claim 4 , wherein the at least one protrusion is a plurality of protrusions.

7. The liquid ejection substrate is a discharge path forming substrate having a discharge path communicating with the discharge port; an element substrate including the electrode terminals and energy generating elements electrically connected to the electrode terminals and configured to generate energy for discharging liquid from the discharge paths; a membrane having the discharge port surface; The head substrate according to claim 1 , comprising:

8. 8. The head substrate according to claim 7, wherein the thickness of the film is 0.2 [mu]m or more.

9. the ejection path forming substrate has a bonding surface to which the film is bonded, the bonding surface having a first peripheral edge portion on the opposite side to the electrode terminal, and two second peripheral edge portions connected to the first peripheral edge portion at a predetermined angle; The head substrate according to claim 7 , wherein the film is provided inside the first peripheral edge portion and the two second peripheral edge portions.

10. The head substrate according to claim 4 , wherein the energy generating element is a piezoelectric element.

11. a first side surface having a first step; a second side surface having a second step and facing the first side surface; an ejection port surface connected to the first side surface and having an ejection port formed therein for ejecting liquid; an electrode terminal provided on a surface of the second step facing in a direction opposite to the ejection port surface; and a connection portion between the ejection port surface and the first side surface is provided in a recessed portion of the first step;

12. The head substrate according to claim 1 ; an electric wiring board electrically connected to the electrode terminals of the head substrate; A liquid ejection head having:

13. a temporary fixing step of temporarily fixing, to a jig, a head substrate to which a liquid ejection substrate having an ejection port surface on which ejection ports for ejecting liquid are formed, a back surface of the ejection port surface, and electrode terminals, and a liquid supply substrate that supplies the liquid to the liquid ejection substrate are bonded; an electrical connection step of electrically connecting an electrical wiring board to the electrode terminals of the temporarily fixed head substrate, the liquid supply substrate is bonded to the rear surface of the liquid ejection substrate, the electrode terminals are provided on the rear surface and are adjacent to the liquid supply substrate in a first direction; at least one of the liquid ejection substrate and the liquid supply substrate has at least one protruding portion located on the opposite side of the electrode terminal in the first direction, and the at least one protruding portion protrudes in the first direction beyond the ejection port surface; The method for manufacturing a liquid ejection head, wherein the temporary fixing step includes abutting the at least one protruding portion against the jig.

14. The method for manufacturing a liquid ejection head according to claim 13, further comprising a separation step of cutting a wafer on which the head substrates are formed by stealth dicing, and cutting out the head substrates from the wafer.

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