JP2022066423A - Liquid discharge head substrate, method of manufacturing the same, liquid discharge head, and liquid discharge apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique for improving performance of a liquid discharge head substrate.

SOLUTION: A method of manufacturing a liquid discharge head substrate includes: a first forming step of forming a first substrate that includes a semiconductor element and a first wiring structure; a second forming step of forming a second substrate that includes a liquid discharge element and a second wiring structure; and a bonding step of bonding the first wiring structure and the second wiring structure such that the semiconductor element and the liquid discharge element are electrically connected to each other after the first forming step and the second forming step. A first surface of the first wiring structure includes a first conductive portion, a first insulating portion, and a second insulating portion, and the first conductive portion is located between the first insulating portion and the second insulating portion. A second surface of the second wiring structure includes a second conductive portion, a third insulating portion, and a fourth insulating portion, and the second conductive portion is located between the third insulating portion and the fourth insulating portion. In the bonding step, the first conductive portion and the second conductive portion are bonded to each other, the first insulating portion and the third insulating portion are bonded to each other, and the second insulating portion and the fourth insulating portion are bonded to each other.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a substrate for a liquid discharge head, a method for manufacturing the same, a liquid discharge head, and a liquid discharge device.

A liquid ejection head is widely used as a part of a recording device that records information such as characters and images on a sheet-shaped recording medium such as paper or film. Patent Document 1 describes a method of forming a substrate for a liquid discharge head by forming a wiring structure on a semiconductor substrate on which a circuit element is formed and forming a heat generation resistance element on the wiring structure. There is. The wiring structure includes a plurality of wiring layers, and the upper surface thereof is flattened each time each wiring layer is formed.

Japanese Unexamined Patent Publication No. 2016-137705

In the liquid discharge head substrate, the liquid discharge characteristics of the heat generation resistance element are determined by the thickness of the insulating layer between the heat generation resistance element and the conductive member immediately below the heat generation resistance element. If the thickness of the insulating layer is larger than the design value, the heat dissipation from the heat generation resistance element to the conductive member is lowered, so that the amount of liquid discharged is larger than the design value. On the other hand, if the thickness of the insulating layer is smaller than the design value, the heat dissipation from the heat generation resistance element to the conductive member is increased, so that the amount of liquid discharged is smaller than the design value. In the manufacturing method described in Patent Document 1, a heat generation resistance element is formed on the uppermost wiring layer. Since the upper surface is flattened each time a wiring layer is formed, the higher the wiring layer, the lower the flatness. Therefore, it is difficult to form a substrate for a liquid discharge head so that the thickness of the insulating layer between the heat generation resistance element and the conductive member immediately below the heat generation resistance element matches the design value over the entire wafer, and it is difficult to form the substrate for the liquid discharge head. The performance of the substrate could not be sufficiently improved. An object of the present invention is to provide a technique for improving the performance of a substrate for a liquid discharge head.

In view of the above problems, a method for manufacturing a substrate for a liquid discharge head, the first forming step of forming a first substrate having a semiconductor element and a first wiring structure, and a first method having a liquid discharge element and a second wiring structure. After the second forming step of forming the two substrates, the first forming step, and the second forming step, the first wiring structure and the said so that the semiconductor element and the liquid discharge element are electrically connected. It has a joining step of joining a second wiring structure, and the first surface of the first wiring structure includes a first conductive portion, a first insulating portion, and a second insulating portion, and the first surface thereof. The conductive portion is located between the first insulating portion and the second insulating portion, and the second surface of the second wiring structure includes a second conductive portion, a third insulating portion, and a fourth insulating portion. The second conductive portion is located between the third insulating portion and the fourth insulating portion, and in the joining step, the first conductive portion and the second conductive portion are joined to each other. Provided is a manufacturing method characterized in that the first insulating portion and the third insulating portion are joined to each other, and the second insulating portion and the fourth insulating portion are joined to each other.

By the above means, the performance of the liquid discharge head substrate is improved.

The figure explaining the structural example of the substrate for the liquid discharge head of 1st Embodiment. The figure explaining the example of the manufacturing method of the substrate for a liquid discharge head of 1st Embodiment. The figure explaining the example of the manufacturing method of the substrate for a liquid discharge head of 1st Embodiment. The figure explaining the example of the manufacturing method of the substrate for a liquid discharge head of 1st Embodiment. The figure explaining the substrate for the liquid discharge head of 2nd Embodiment. The figure explaining the substrate for the liquid discharge head of 3rd Embodiment. The figure explaining the substrate for the liquid discharge head of 4th Embodiment. The figure explaining the substrate for the liquid discharge head of 5th Embodiment. The figure explaining the substrate for the liquid discharge head of 6th Embodiment. The figure explaining other embodiment. The figure explaining the substrate for the liquid discharge head of 7th Embodiment. The figure explaining the substrate for the liquid discharge head of 7th Embodiment. The figure explaining the substrate for the liquid discharge head of 8th Embodiment.

Embodiments of the present invention will be described below with reference to the accompanying drawings. Similar elements are designated by the same reference numerals throughout the various embodiments, and duplicate description is omitted. In addition, each embodiment can be changed and combined as appropriate. Hereinafter, the liquid discharge head substrate is simply referred to as a discharge substrate. The discharge board is used for liquid discharge devices such as copiers, facsimiles, and word processors. In the following embodiment, the heat generation resistance element is treated as an example of the liquid discharge element included in the discharge substrate. The liquid discharge element may be an element capable of imparting energy to the liquid, for example, a piezoelectric element.

<First Embodiment>
A configuration example of the discharge board 100 according to the first embodiment will be described with reference to FIG. 1. FIG. 1A is a cross-sectional view focusing on a part of the discharge substrate 100, and FIG. 1B is an enlarged view of a region 100a of FIG. 1A.

The discharge substrate 100 has a base material 110, a wiring structure 120, a heat generation resistance element 130, a protective film 140, a cavitation resistant film 150, and a nozzle structure 160. The base material 110 is a semiconductor layer such as silicon. A semiconductor element 111 such as a transistor and an element separation region 112 such as LOCOS or STI are formed on the base material 110.

The wiring structure 120 is located on the base material 110. The wiring structure 120 is divided into a wiring structure 120a below the joint surface 121 and a wiring structure 120b above the joint surface 121 with the flat joint surface 121 as a boundary. The wiring structure 120a has an insulating member 122 and a plurality of layers of conductive members 123 to 125 inside the insulating member 122. The plurality of layers of the conductive members 123 to 125 are laminated. The conductive member 123 of the layer closest to the base material 110 is connected to a semiconductor element 111 or the like formed on the base material 110 by a plug. Further, the conductive members located in the adjacent layers among the plurality of layers are connected to each other by a plug.

The wiring structure 120b has an insulating member 126 and a plurality of layers of conductive members 127 and 128 inside the insulating member 126. The plurality of layers of conductive members 127 and 128 are laminated. The conductive member 128 of the layer farthest from the base material 110 is connected to the heat generation resistance element 130 by a plug. Further, the conductive member 127 and the conductive member 128 are connected to each other by a plug.

Each of the conductive members 123 to 125, 127, and 128 may have a dummy pattern in a part thereof. The dummy pattern is a conductive pattern that is not electrically connected to the semiconductor element 111 and does not contribute to signal transmission or power supply. Each of the conductive members 123 to 125, 127, and 128 may be composed of a barrier metal layer and a metal layer. The barrier metal layer is formed of, for example, tantalum, a tantalum compound, titanium, or a titanium compound, and suppresses the diffusion and mutual reaction of the materials contained in the metal layer. The metal layer is made of copper or an aluminum compound and has a lower resistance than the barrier metal layer.

As shown in FIG. 1B, the conductive member 125 is composed of a metal layer 125a and a barrier metal layer 125b. The barrier metal layer 125b is arranged between the metal layer 125a and the insulating member 122. The conductive member 127 is composed of a metal layer 127a and a barrier metal layer 127b. The barrier metal layer 127b is arranged between the metal layer 127a and the insulating member 126. At the joint surface 121, the metal layer 125a and the metal layer 127a, the barrier metal layer 125a and the barrier metal layer 125b, and the insulating member 122 and the insulating member 126 are bonded to each other. Since the joint surface 121 is flat, the upper surface of the conductive member 125 and the upper surface of the insulating member 122 are on the same surface, and the lower surface of the conductive member 127 and the lower surface of the insulating member 126 are on the same surface. As will be described later, the discharge substrate 100 is manufactured by joining two substrates. Therefore, depending on the variation in alignment accuracy and processing accuracy at the time of joining, a part of the metal layer 125a may be joined to a part of the barrier metal layer 127b, or a part of the metal layer 127a may be joined to a part of the barrier metal layer 125b. It may happen. The thickness of the barrier metal layer 125b may be adjusted so that the metal layer 125a and the insulating member 126 do not join even if the alignment accuracy and the processing accuracy vary. The same applies to the joining between the metal layer 127a and the insulating member 122.

The heat generation resistance element 130 is located above the wiring structure 120. The side surface of the heat generation resistance element 130 is in contact with the insulating member 126. The upper surface of the heat generation resistance element 130 is on the same surface as the upper surface of the wiring structure 120, that is, the upper surface of the insulating member 126. The semiconductor element 111 and the heat generation resistance element 130 are electrically connected to each other by the wiring structure 120 (specifically, by the conductive member included in the wiring structure 120). The heat generation resistance element 130 is formed of, for example, tantalum or a tantalum compound. Instead of this, the heat generation resistance element 130 may be formed of polysilicon or tungsten silicide.

The conductive member 128 of the layer closest to the heat generation resistance element 130 among the plurality of layers of the conductive members 123 to 125, 127, 128 includes a conductive portion directly below the heat generation resistance element 130. The liquid discharge characteristic of the heat generation resistance element 130 is determined by the thickness of the region 126a between the conductive portion of the insulating member 126 and the heat generation resistance element 130. If the thickness of the insulating layer is larger than the design value, the heat dissipation from the heat generation resistance element 130 to the conductive member is lowered, so that the amount of liquid discharged is larger than the design value. On the other hand, if the thickness of the insulating layer is smaller than the design value, the heat dissipation from the heat generation resistance element 130 to the conductive member is increased, so that the amount of liquid discharged is smaller than the design value. The region 126a may also be referred to as a heat storage region.

The protective film 140 is located on the wiring structure 120 and the heat generation resistance element 130. The protective film 140 covers at least the upper surface of the heat generation resistance element 130, and also covers the upper surface of the wiring structure 120 in this embodiment. The protective film 140 is composed of, for example, SIO, SION, SIOC, SIC, and SIN, and protects the heat generation resistance element 130 from erosion of liquid. In the present embodiment, both sides of the protective film 140, that is, the surface on the heat generation resistance element 130 side and the opposite surface are flat. Therefore, as compared with the case where the protective film has a step, the coverage of the heat generation resistance element 130 can be sufficiently ensured even if the protective film 140 is thin. By making the protective film 140 thinner, the energy transfer efficiency to the liquid is improved, and it is possible to achieve both reduction in power consumption and high image quality by stabilizing foaming.

The cavitation resistant film 150 is located on the protective film 140. The cavitation resistant film 150 covers the heat generation resistance element 130 with the protective film 140 interposed therebetween. The cavitation resistant film 150 is formed of, for example, tantalum, and protects the heat generation resistance element 130 and the protective film 140 from physical impact during liquid discharge.

The nozzle structure 160 is located on the protective film 140 and the cavitation resistant film 150. The nozzle structure 160 has an adhesion layer 161, a nozzle material 162, and a water repellent material 163. The nozzle structure 160 is formed with a flow path 164 and a discharge port 165 for the discharged liquid.

Subsequently, a method for manufacturing the discharge substrate 100 will be described with reference to FIGS. 2 to 4. First, as shown in FIG. 2, a substrate 200 having a semiconductor element 111 is formed. Hereinafter, a method for forming the substrate 200 will be specifically described. As shown in FIG. 2A, the semiconductor element 111 and the element separation region 112 are formed on the base material 110 of the semiconductor material. The semiconductor element 111 may be a switch element such as a transistor. The element separation region 112 may be formed by the LOCOS method or the STI method.

After that, the structure shown in FIG. 2 (b) is formed. Specifically, the insulating layer 201 is formed on the base material 110, a hole is formed in the insulating layer 201, and a plug 202 is formed in the hole. The plug 202 is formed, for example, by forming a metal film on the insulating layer 201 and removing a portion of the metal film other than the portion that has entered the hole of the insulating layer 201 by an etchback method or a CMP method. The insulating layer 201 is formed of, for example, SIO, SIN, SIC, SION, SIOC, and SICN. The upper surface of the insulating layer 201 may be flattened.

After that, the structure shown in FIG. 2 (c) is formed. Specifically, the insulating layer 203 is formed on the insulating layer 201, and an opening is formed in the insulating layer 203. A barrier metal layer is formed on the insulating layer 203, and a metal layer is formed on the barrier metal layer. The conductive member 123 is formed by removing the portion of the barrier metal layer and the metal film other than the portion that has entered the opening of the insulating layer 203 by the etchback method or the CMP method. The barrier metal layer is formed of, for example, tantalum, a tantalum compound, titanium, or a titanium compound, and the conductive member 123 is formed of, for example, copper, aluminum, or tungsten. The upper surfaces of the insulating layer 203 and the conductive member 123 may be flattened.

After that, the structure shown in FIG. 2 (d) is formed. Specifically, the insulating layer 204 is formed on the insulating layer 203, and an opening is formed in the insulating layer 204. The conductive member 124 is formed in the same manner as the conductive member 123. The upper surfaces of the insulating layer 204 and the conductive member 124 may be flattened.

After that, the structure shown in FIG. 2 (e) is formed. Specifically, the insulating layer 205 is formed on the insulating layer 204, and an opening is formed in the insulating layer 205. The conductive member 125 is formed in the same manner as the conductive member 124. The upper surfaces of the insulating layer 205 and the conductive member 125 may be flattened.

As a result, the substrate 200 is formed. In the present embodiment, the substrate 200 has three layers of conductive members 123 to 125, but the number of layers of the conductive members is not limited to this, and may be one layer, two layers, or four or more layers. good. Further, the conductive member may have a single damascene structure or a dual damascene structure. The wiring structure of the board 200 is the wiring structure 120a of the discharge board 100. The insulating layers 201, 203, 204, and 205 constitute the insulating member 122 of the wiring structure 120a. The upper surface of the substrate 200 (the surface opposite to the substrate 110) is flat.

The upper limit of the temperature at which the metal materials such as the plug 202 and the conductive members 123, 124, 125 included in the wiring structure 120a are not affected by melting or the like is called the limit temperature. The critical temperature may vary depending on the type of metal material, but may be, for example, 400 ° C, 450 ° C, or 500 ° C. The substrate 200 is formed so that the maximum temperature of the heat history received by the metal material contained in the wiring structure 120a during the manufacture of the substrate 200 is less than the limit temperature (for example, less than 400 ° C, less than 450 ° C, or less than 500 ° C). ..

The thermal history of a certain part of the semiconductor device means the transition of the temperature of the part in the manufacturing process of the semiconductor device including the time when the part is formed. For example, suppose a member is formed at a substrate temperature of 400 ° C. and then the substrate including that portion is treated at a substrate temperature of 350 ° C. In this case, the portion will have a thermal history of 400 ° C and 350 ° C.

Subsequently, as shown in FIG. 3, the substrate 300 having the heat generation resistance element 130 is formed. Either the substrate 200 or the substrate 300 may be formed first. Hereinafter, a method for forming the substrate 300 will be specifically described. As shown in FIG. 3A, the protective film 140 is formed on the base material 301, and the heat generation resistance element 130 is formed on the protective film 140. The base material 301 may be formed of a semiconductor material such as silicon, or may be formed of an insulator material such as glass.

The protective film 140 is formed of a silicon insulator such as silicon dioxide, silicon nitride, or silicon carbide. In order to improve the moisture resistance of the protective film 140, the protective film 140 may be heat-treated at a high temperature. Generally, the higher the temperature used for heat treatment of an insulator, the better the moisture resistance. Since the wiring structure has not been formed yet at this point, the protective film 140 can be heat-treated at a temperature equal to or higher than the limit temperature (for example, 400 ° C or higher, 450 ° C or higher or 500 ° C or higher, specifically 650 ° C). Further, the upper surface of the protective film 140 may be flattened by a CMP method or the like before the heat generation resistance element 130 is formed. Instead of heat-treating the heat generation resistance element 130, plasma treatment may be performed. In the present embodiment, the protective film 140 has high moisture resistance, so that the life of the discharge substrate 100 is improved.

The heat generation resistance element 130 is formed of, for example, tantalum or a tantalum compound. The heat generation resistance element 130 may be heat-treated at a temperature equal to or higher than the limit temperature (for example, 400 ° C. or higher, 450 ° C. or higher or 500 ° C. or higher, specifically 650 ° C.). As a result, the resistance value of the heat generation resistance element 130 can be improved, and the power saving of the discharge substrate 100 becomes possible. Further, by heat-treating the heat-generating resistance element 130 at a temperature equal to or higher than the limit temperature, the heat-generating resistance element 130 can be crystallized and the initial characteristics of the heat-generating resistance element 130 can be stabilized. The heat generation resistance element 130 may be formed of tantalum or polysilicon having a higher resistance than the tantalum compound. A high temperature process is required to form the heat generation resistance element 130 from polysilicon, but as described above, the heat generation resistance element 130 can be formed at a temperature equal to or higher than the limit temperature. In addition, as the material of the heat generation resistance element 130, a material that cannot be used below the limit temperature can be selected.

A conductive member for wiring may be formed in the same layer as the heat generation resistance element 130. In this case, it is not necessary to heat-treat the heat generation resistance element 130 at the limit temperature or higher. The protective film 140 and the heat generation resistance element 130 may be heat-treated separately or at the same time. At least one of the protective film 140 and the heat generation resistance element 130 is heat-treated at a temperature equal to or higher than the limit temperature.

After that, the structure shown in FIG. 3 (b) is formed. Specifically, the insulating layer 302 is formed on the protective film 140 and the heat generation resistance element 130, a hole is formed in the insulating layer 302, and a plug 303 is formed in the hole. The plug 303 is formed, for example, by forming a metal film of copper or tungsten on the insulating layer 302 and removing a portion of the metal film other than the portion that has entered the hole of the insulating layer 302 by an etchback method or a CMP method. To. The insulating layer 302 is formed of, for example, SIO, SIN, SIC, SION, SIOC, and SICN. Further, the thickness of the insulating layer 302 may be adjusted by flattening the upper surface of the insulating layer 302.

After that, as shown in FIG. 3C, the conductive member 128 is formed on the insulating layer 302. The conductive member 128 is made of copper or aluminum. After that, as shown in FIG. 3D, the insulating layer 304 is formed on the insulating layer 302 and the conductive member 128, and the plug 305 is formed on the insulating layer 304. The plug 305 includes a barrier metal layer and a metal layer, the barrier metal layer is, for example, titanium or a titanium compound, and the metal layer is, for example, a tungsten layer.

After that, as shown in FIG. 3 (e), the insulating layer 306 and the conductive member 127 are formed on the insulating layer 304. The conductive member 127 includes a barrier metal layer and a metal layer, the barrier metal layer is, for example, tantalum, a tantalum compound, titanium, and a titanium compound, and the metal layer is, for example, copper or aluminum.

As a result, the substrate 300 is formed. In the present embodiment, the substrate 300 has two layers of conductive members, but the number of layers of the conductive members is not limited to this, and may be one layer or three or more layers. Further, the conductive member may have a single damascene structure or a dual damascene structure. The wiring structure of the board 300 is the wiring structure 120b of the discharge board 100. The insulating layers 302, 304, and 306 form the insulating member 126 of the wiring structure 120b. The upper surface of the substrate 300 (the surface opposite to the substrate 301) is flat.

The maximum temperature of the heat history received by the heat generation resistance element 130 or the protective film 140 during the manufacture of the substrate 300 is equal to or higher than the limit temperature, and the maximum temperature of the heat history received by the metal material included in the wiring structure 120b is lower than the limit temperature. The substrate 300 is formed. The metal materials included in the wiring structure 120b are, for example, plugs 303 and 305 and conductive members 127 and 128.

In the manufacturing method in which the wiring structure is formed on the base material having the semiconductor element and the heat generation resistance element is formed on the wiring structure, the heat generation resistance element is formed on the uppermost wiring layer. Since the upper surface is flattened each time a wiring layer is formed, the higher the wiring layer, the lower the flatness. On the other hand, in the above-described method for manufacturing the substrate 300, the insulating member 126 is formed with the insulating layer 302 closest to the protective film 140 and the heat generation resistance element 130 before the other insulating layers of the wiring structure 120. The flatness of the insulating layer 302 is high. As a result, it becomes easy to form the substrate 300 so that the thickness of the region 126a of the insulating layer 302 matches the design value over the entire wafer, and the ejection performance of the heat generation resistance element 130 is improved.

Subsequently, as shown in FIG. 4A, the wiring structure of the substrate 200 and the wiring structure of the substrate 300 are joined to each other so that the semiconductor element 111 and the heat generation resistance element 130 are electrically connected. Specifically, the conductive member 125 and the conductive member 127 are joined to each other, and the insulating member 122 and the insulating member 126 are joined to each other. The bonding between the substrate 200 and the substrate 300 may be performed by heating in a state where these are stacked, or a catalyst such as argon may be used for the bonding.

Then, as shown in FIG. 4 (b), the entire base material 301 is removed. After that, the ejection substrate 100 is manufactured by forming the cavitation resistant film 150 and the nozzle structure 160. The step of FIG. 4 may be performed at a temperature below the limit temperature. Therefore, the maximum temperature of the heat history received by the heat generation resistance element 130 or the protective film 140 during the manufacture of the discharge substrate 100 is higher than the maximum temperature of the heat history received by the conductive member included in the wiring structure 120 during the manufacture of the discharge substrate 100. expensive.

Each step of the above-mentioned manufacturing method may be executed by a single operator or may be executed by a plurality of operators. For example, one business operator may form a substrate 200 and a substrate 300, and another business operator may prepare the substrate 200 and the substrate 300 by purchasing or the like, and then join them. Alternatively, one operator may form the substrate 200 and the substrate 300, and this operator may instruct another operator to join them.

<Second Embodiment>
A configuration example of the discharge substrate 500 according to the second embodiment and a manufacturing method thereof will be described with reference to FIG. Description of the same parts as in the first embodiment will be omitted. The manufacturing method of the discharge substrate 500 may be the same as the manufacturing method of the discharge substrate 100 up to the step shown in FIG. 4A. Then, as shown in FIG. 5A, instead of removing the entire base material 301, the portion of the base material 301 that overlaps with the heat generation resistance element 130 is removed. As a result, an opening 501 is formed in the remaining portion of the base material 301. The opening 501 is located above the heat generation resistance element 130.

After that, as shown in FIG. 5B, the nozzle material 162 and the water repellent material 163 are formed on the base material 301. The nozzle material 162 and the water-repellent material 163 form a discharge port 165. The opening 501 of the base material 301 constitutes a part of the flow path 164 of the discharged liquid. As a result, the discharge board 500 is manufactured.

The discharge substrate 500 shown in FIG. 5B does not have a cavitation resistant film, but after removing a part of the base material 301, a cavitation resistant film is formed so as to sandwich the protective film 140 and cover the heat generation resistance element 130. You may. Further, an adhesion layer for improving the adhesion may be formed between the base material 301 and the nozzle material 162. According to this embodiment, a part of the base material 301 can also be used as a nozzle structure.

<Third Embodiment>
A configuration example of the discharge board 600 according to the third embodiment will be described with reference to FIG. Description of the same parts as in the first embodiment will be omitted. The shape of the conductive member 128 of the discharge board 600 is different from that of the discharge board 100. In the discharge substrate 600, the conductive member 128 in the layer closest to the heat generation resistance element 130 among the plurality of layers of the conductive members does not include the conductive portion directly under the heat generation resistance element 130, and the conductive member 127 in the next closest layer is the conductive member 127. Includes conductive parts. Therefore, the region 126b between the heat generation resistance element 130 and the conductive member 127 becomes the heat storage region. According to the present embodiment, the heat storage region can be widened as compared with the first embodiment. The size of the heat storage area is not limited to this. For example, the heat storage region may straddle the joint surface 121.

<Fourth Embodiment>
A configuration example of the discharge board 700 and a manufacturing method thereof according to the fourth embodiment will be described with reference to FIG. 7. Description of the same parts as in the first embodiment will be omitted. As for the manufacturing method of the discharge substrate 700, the manufacturing method of the substrate 300 is different from the manufacturing method of the discharge substrate 100.

As shown in FIG. 7A, the protective film 140 and the heat generation resistance element 130 are formed on the base material 301 in the same manner as in the first embodiment. When the heat generation resistance element 130 is formed thinly, for example, when the heat generation resistance element 130 is formed with a film thickness of several to several tens of nm, poor contact between the heat generation resistance element 130 and the plug may occur. In order to avoid such poor contact, a conductive member is arranged between the heat generation resistance element 130 and the plug 303. This conductive member may be referred to as a connection assisting member.

Specifically, as shown in FIG. 7B, the conductive film 701 is formed on the heat generation resistance element 130. The conductive film 701 is, for example, an aluminum alloy. Then, as shown in FIG. 7 (c), the conductive member 702 is formed by removing a part of the conductive film 701 by a dry etching method or a wet etching method. The conductive member 702 is in contact with only both sides of the heat generation resistance element 130, and is not in contact with the central portion of the heat generation resistance element 130. After that, as shown in FIG. 7D, the insulating layer 302 and the plug 303 are formed. After that, the discharge substrate 700 shown in FIG. 7 (e) is manufactured in the same manner as in the steps after FIG. 3 (c).

<Fifth Embodiment>
With reference to FIG. 8, a configuration example of the discharge board 800 according to the fifth embodiment and a manufacturing method thereof will be described. Description of the same parts as in the first embodiment will be omitted. In the method of manufacturing the discharge board 800, the method of manufacturing the board 300 is different from the method of manufacturing the discharge board 100.

As shown in FIG. 8A, after the protective film 140 and the heat generation resistance element 130 are formed on the base material 301 in the same manner as in the first embodiment, the insulating layer is formed on the protection film 140 and the heat generation resistance element 130. An 802 is formed, and a temperature sensor 801 is formed on the 802. The insulating layer 802 may be made of the same material as the insulating layer 302. After that, the discharge substrate 800 shown in FIG. 8 (b) is manufactured in the same manner as in the steps after FIG. 3 (b).

The temperature sensor 801 is used to measure the temperature of the heat generation resistance element 130 and detect whether or not the ink has been ejected correctly. The temperature sensor 801 is made of a conductive material such as titanium or a titanium compound, which does not have a large rate of change in thermal resistance. The temperature sensor is located closer to the heat generation resistance element 130 than the conductive member 128 in the layer closest to the heat generation resistance element 130 among the plurality of conductive members of the wiring structure 120.

Before forming the temperature sensor 801, the upper surface of the insulating layer 802 is flattened by a CMP method or the like. Since the heat of the heat generation resistance element 130 is transferred to the temperature sensor 801 through the insulating layer 802, the accuracy of the temperature sensor 801 can be improved by accurately forming the thickness of the insulating layer 802. Since there is no other base layer between the insulating layer 802 and the heat generation resistance element 130, the insulating layer 802 having a uniform thickness can be made with high accuracy in the wafer surface. Further, since the temperature sensor 801 is formed before forming the conductive member of the wiring structure, even if the temperature sensor 801 is heat-treated at a temperature equal to or higher than the limit temperature (for example, 400 ° C or higher, 450 ° C or higher, or 500 ° C or higher). good.

<Sixth Embodiment>
A configuration example of the discharge board 900 according to the sixth embodiment and a manufacturing method thereof will be described with reference to FIG. 9. Description of the same parts as in the first embodiment will be omitted. In the method of manufacturing the discharge board 900, the method of manufacturing the board 300 is different from the method of manufacturing the discharge board 100.

As shown in FIG. 9A, after forming the protective film 140 and the heat generation resistance element 130 on the base material 301 in the same manner as in the first embodiment, the protective film 140 and the heat generation resistance element 130 are covered with the protective film. Further forms 901. The protective film 901 may be made of the same material as the protective film 140, and has a temperature equal to or higher than the limit temperature (for example, 400 ° C. or higher, 450 ° C. or higher, or 500 ° C. or higher), specifically, with respect to the protective film 901. The heat treatment may be performed at 650 ° C.). After that, the discharge substrate 900 shown in FIG. 9 (b) is manufactured in the same manner as in the steps after FIG. 3 (b).

Since the discharge board 900 also has a protective film 901 between the heat generation resistance element 130 and the wiring structure 120, oxygen contained in the wiring structure 120 and the base material 110 is supplied to the heat generation resistance element 130. Can be suppressed. As a result, the oxidation of the heat generation resistance element 130 is further suppressed, and the life of the discharge substrate 900 is extended.

<7th Embodiment>
An example of the configuration of the discharge board 1200 according to the seventh embodiment and a method for manufacturing the same will be described with reference to FIGS. 11 and 12. The discharge board 1200 is different from the discharge board 100 in that the board 1100 (FIG. 11 (c)) is used instead of the board 300. In the following description, the description of the same part as that of the first embodiment will be omitted.

The manufacturing method of the discharge board 1200 will be described. As shown in FIG. 11A, a sacrificial layer 166 is formed on the base material 301. After that, as shown in FIG. 11B, the protective film 140 is formed on the base material 301, and the heat generation resistance element 130 is formed on the protective film 140. The protective layer 140 covers the entire surface of the sacrificial layer 166. The heat generation resistance element 130 is arranged at a position overlapping a part of the sacrificial layer 166. After that, the substrate 1100 shown in FIG. 11 (c) is formed in the same manner as in FIGS. 3 (b) to 3 (e) of the first embodiment.

Subsequently, as shown in FIG. 11D, the wiring structure of the substrate 200 and the wiring structure of the substrate 1100 are joined to each other in the same manner as in the first embodiment. After that, as shown in FIG. 12, a water-repellent material 163 is formed on the base material 310, a discharge port 165 is formed, and the sacrificial layer 166 is removed through the discharge port 165. As a result, the discharge board 1200 is manufactured. The base material 310 after removing the sacrificial layer 166 constitutes a part of the flow path 164 of the discharged liquid. According to the present embodiment, since the adhesion layer 161 can be reduced as compared with the first embodiment, the nozzle generation step can be reduced.

<8th Embodiment>
With reference to FIG. 13, a configuration example of the discharge board 1200 according to the eighth embodiment and a manufacturing method thereof will be described. The discharge board 1300 has a different flow path 164 structure from the discharge board 1200. The description of the same part as in the seventh embodiment will be omitted.

Hereinafter, a method for manufacturing the discharge substrate 1300 will be described. As shown in FIG. 11D, the steps up to the step of joining the wiring structure of the substrate 200 and the wiring structure of the substrate 1100 to each other are the same as those of the seventh embodiment. Then, as shown in FIG. 13A, the base material 301 is thinned so that the upper surface of the sacrificial layer 166 is exposed. This thinning may be performed, for example, by polishing.

After that, as shown in FIG. 13B, the sacrificial layer 166 is removed, the nozzle material 162 is formed, the water repellent material 163 is formed, and the discharge port 165 is formed. As a result, the discharge board 1300 is manufactured. The base material 310 after removing the sacrificial layer 166 constitutes a part of the flow path 164 of the discharged liquid. According to the present embodiment, since the adhesion layer 161 can be reduced as compared with the first embodiment, the nozzle generation step can be reduced.

<Other embodiments>
FIG. 10A illustrates the internal configuration of the liquid ejection device 1600 represented by an inkjet printer, facsimile, copier, and the like. In this example, the liquid discharge device may be referred to as a recording device. The liquid ejection device 1600 includes a liquid ejection head 1510 that ejects a liquid (ink, recording agent in this example) onto a predetermined medium P (recording medium such as paper in this example). In this example, the liquid discharge head may be referred to as a recording head. The liquid discharge head 1510 is mounted on the carriage 1620, which may be mounted on a lead screw 1621 having a spiral groove 1604. The lead screw 1621 can rotate in conjunction with the rotation of the drive motor 1601 via the drive force transmission gears 1602 and 1603. As a result, the liquid discharge head 1510 can move together with the carriage 1620 in the direction of the arrow a or b along the guide 1619.

The medium P is pressed by the paper presser plate 1605 along the carriage moving direction and is fixed to the platen 1606. The liquid discharge device 1600 reciprocates the liquid discharge head 1510 to discharge liquid (recorded in this example) to the medium P conveyed on the platen 1606 by a transfer unit (not shown).

Further, the liquid discharge device 1600 confirms the position of the lever 1609 provided on the carriage 1620 via the photocouplers 1607 and 1608, and switches the rotation direction of the drive motor 1601. The support member 1610 supports a cap member 1611 for covering the nozzle (liquid discharge port, or simply discharge port) of the liquid discharge head 1510. The suction unit 1612 performs a recovery process of the liquid discharge head 1510 by sucking the inside of the cap member 1611 through the opening inside the cap 1613. The lever 1617 is provided to start the recovery process by suction, moves with the movement of the cam 1618 engaged with the carriage 1620, and the driving force from the drive motor 1601 is controlled by a known transmission mechanism such as clutch switching. Will be done.

Further, the main body support plate 1616 supports the moving member 1615 and the cleaning blade 1614, and the moving member 1615 moves the cleaning blade 1614 and performs a recovery process of the liquid discharge head 1510 by wiping. Further, the liquid discharge device 1600 is provided with a control unit (not shown), and the control unit controls the drive of each of the above-mentioned mechanisms.

FIG. 10B illustrates the appearance of the liquid discharge head 1510. The liquid discharge head 1510 may include a head portion 1511 having a plurality of nozzles 1500, and a tank (liquid storage portion) 1512 for holding a liquid to be supplied to the head portion 1511. The tank 1512 and the head portion 1511 can be separated from each other by, for example, a broken line K, and the tank 1512 can be replaced. The liquid discharge head 1510 includes an electrical contact (not shown) for receiving an electrical signal from the carriage 1620, and discharges the liquid according to the electrical signal. The tank 1512 has, for example, a fibrous or porous liquid holding material (not shown), and the liquid holding material can hold a liquid.

FIG. 10C illustrates the internal configuration of the liquid discharge head 1510. The liquid discharge head 1510 includes a substrate 1508, a channel wall member 1501 arranged on the substrate 1508 and forming a flow path 1505, and a top plate 1502 having a liquid supply path 1503. Further, as a discharge element or a liquid discharge element, a heater 1506 (electric heat conversion element) is arranged on a substrate (a substrate for a liquid discharge head) included in the liquid discharge head 1510 corresponding to each nozzle 1500. Each heater 1506 is driven by the driving element (switch element such as a transistor) provided corresponding to the heater 1506 becoming conductive, and generates heat.

The liquid from the liquid supply path 1503 is stored in the common liquid chamber 1504 and is supplied to each nozzle 1500 via each flow path 1505. The liquid supplied to each nozzle 1500 is discharged from the nozzle 1500 in response to driving the heater 1506 corresponding to the nozzle 1500.

FIG. 10D illustrates the system configuration of the liquid discharge device 1600. The liquid discharge device 1600 has an interface 1700, MPU1701, ROM1702, RAM1703 and a gate array (GA) 1704. An external signal for executing liquid discharge is input to the interface 1700 from the outside. The ROM 1702 stores a control program executed by the MPU 1701. The RAM 1703 stores various signals or data such as the above-mentioned external signal for liquid discharge and data supplied to the liquid discharge head 1708. The gate array 1704 controls the supply of data to the liquid discharge head 1708, and also controls the data transfer between the interfaces 1700, MPU1701, and RAM1703.

The liquid discharge device 1600 further includes a head driver 1705, motor drivers 1706 and 1707, a transfer motor 1709, and a carrier motor 1710. The carrier motor 1710 conveys the liquid discharge head 1708. The transfer motor 1709 conveys the medium P. The head driver 1705 drives the liquid discharge head 1708. The motor drivers 1706 and 1707 drive the carrier motor 1709 and the carrier motor 1710, respectively.

When a drive signal is input to the interface 1700, the drive signal can be converted into data for liquid discharge between the gate array 1704 and the MPU 1701. Each mechanism performs a desired operation according to this data, and thus the liquid discharge head 1708 is driven.

100 Discharge board, 110 base material, 120 wiring structure, 130 heat generation resistance element, 140 protective film, 150 cavitation resistant film, 160 nozzle structure

Claims (20)

A method for manufacturing a substrate for a liquid discharge head.
A first forming step of forming a first substrate having a semiconductor element and a first wiring structure,
A second forming step of forming a liquid discharge element and a second substrate having a second wiring structure, and
After the first forming step and the second forming step, a joining step of joining the first wiring structure and the second wiring structure so that the semiconductor element and the liquid discharge element are electrically connected. ,
Have,
The first surface of the first wiring structure includes a first conductive portion, a first insulating portion, and a second insulating portion, and the first conductive portion includes the first insulating portion and the second insulating portion. Located between
The second surface of the second wiring structure includes a second conductive portion, a third insulating portion, and a fourth insulating portion, and the second conductive portion includes the third insulating portion and the fourth insulating portion. Located between
In the joining process
The first conductive portion and the second conductive portion are joined to each other,
The first insulating portion and the third insulating portion are joined to each other, and the first insulating portion and the third insulating portion are joined to each other.
A manufacturing method characterized in that the second insulating portion and the fourth insulating portion are joined to each other. The manufacturing method according to claim 1, wherein the second forming step includes a step of forming the second wiring structure after forming the liquid discharge element. The second forming step is
The process of forming a protective film on the substrate and
The step of forming the liquid discharge element on the protective film and
The step of forming the second wiring structure on the liquid discharge element and
The manufacturing method according to claim 2, wherein the product comprises. 3. The second forming step further includes a step of heat-treating at least one of the liquid discharge element and the protective film at a temperature of 400 ° C. or higher before forming the second wiring structure. The manufacturing method described in. The step of forming the second wiring structure is
The step of forming an insulating layer on the liquid discharge element and
The step of flattening the upper surface of the insulating layer and
The production method according to claim 3 or 4, wherein the production method comprises. The second wiring structure includes an insulating member and a plurality of layers of conductive members inside the insulating member.
The present invention according to any one of claims 3 to 5, wherein the conductive member of the layer closest to the liquid discharge element among the plurality of layers of the conductive members does not include the conductive portion directly under the liquid discharge element. The manufacturing method described. The second wiring structure further includes a temperature sensor for measuring the temperature of the liquid discharge element inside the insulating member.
The manufacturing method according to claim 6, wherein the temperature sensor is located closer to the liquid discharge element than the conductive member in the nearest layer. The manufacturing method according to claim 7, wherein the second forming step further includes a step of heat-treating the temperature sensor at a temperature of 400 ° C. or higher before forming the plurality of layers of the conductive member. The manufacturing method according to any one of claims 3 to 8, further comprising a step of removing a portion of the base material that overlaps with the liquid discharge element after the joining step. The manufacturing method according to claim 9, wherein the remaining portion of the base material constitutes a part of the flow path of the discharged liquid. The manufacturing method according to claim 10, further comprising a step of forming a cavitation-resistant film that covers the liquid discharge element by sandwiching the protective film after removing the overlapping portion of the base material. The second forming step further includes a step of forming a sacrificial layer on the base material before the step of forming the protective film on the base material.
The manufacturing method further comprises a step of removing the sacrificial layer after the joining step.
The manufacturing method according to any one of claims 3 to 8, wherein the base material after removing the sacrificial layer constitutes a part of a flow path of the discharged liquid. The protective film is the first protective film.
The second forming step is
After forming the liquid discharge element, a step of forming a second protective film covering the liquid discharge element, and
The step of heat-treating the second protective film at a temperature of 400 ° C. or higher, and
The production method according to any one of claims 3 to 12, further comprising. The manufacturing method according to any one of claims 1 to 13, wherein the liquid discharge element is a heat generation resistance element. The manufacturing method according to any one of claims 1 to 14, wherein the joining step includes heating the first substrate and the second substrate. The production according to any one of claims 1 to 15, wherein the joining step includes joining the first wiring structure and the second wiring structure using a catalyst. Method. The production method according to claim 16, wherein the catalyst contains argon. A substrate for a liquid discharge head
The first base material on which the semiconductor element was formed and
The first wiring structure located on the first base material and
The second wiring structure located on the first wiring structure and
The liquid discharge element located on the second wiring structure and
A second base material having an opening at a position overlapping the liquid discharge element,
Equipped with
The first surface of the first wiring structure includes a first conductive portion, a first insulating portion, and a second insulating portion, and the first conductive portion includes the first insulating portion and the second insulating portion. Located between
The second surface of the second wiring structure includes a second conductive portion, a third insulating portion, and a fourth insulating portion, and the second conductive portion includes the third insulating portion and the fourth insulating portion. Located between
The first conductive portion and the second conductive portion are joined to each other.
The first insulating portion and the third insulating portion are joined to each other.
A substrate for a liquid discharge head, wherein the second insulating portion and the fourth insulating portion are joined to each other. The liquid discharge head according to claim 18, further comprising a liquid discharge head substrate and a discharge port whose liquid discharge is controlled by the liquid discharge head substrate. The liquid discharge device according to claim 19, further comprising a liquid discharge head and a supply means for supplying a drive signal for discharging the liquid to the liquid discharge head.

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