Recording head and method for manufacturing the recording head

Abstract

To inhibit damage of a component during bonding.SOLUTION: A recording head has a metallic layer formed on laminated layers and includes: an electric wiring layer which establishes electric continuity with the metallic layer 210; a protection film 207 which covers and protects the electric wiring layer; grooves 221 which divide the protection film 207 and the electric wiring layer around the metallic layer 210; and a resin film 211 applied to the grooves 221.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present disclosure relates to a recording head and a method for manufacturing the recording head.

Background Art

[0002] Patent Document 1 describes an inkjet print head (hereinafter also referred to as a "recording head") that connects an electrical connection pad (hereinafter also referred to as an "electrode") and a lead by a gang bonding method.

[0003] In addition, it is necessary to form bumps on the electrodes of the recording head. In recent years, mainly plating bumps have been adopted in order to shorten the manufacturing process of the recording head.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When bonding a lead to an electrode, in order to suppress damage to components on the substrate, it is required to pay attention to impact loads and the like when the bonding tool grounds to the bump via the lead.

[0006] In order to solve such problems, the recording head according to the present disclosure aims to suppress damage to components during bonding.

Means for Solving the Problems

[0007] In order to achieve the above object, the recording head according to the present disclosure is a recording head including a metal film formed on a stacked layer, and includes an electrical wiring layer electrically connected to the metal film, a protective film covering and protecting the electrical wiring layer, a groove that divides the protective film and the electrical wiring layer around the metal film, and a resin film applied to the groove.

Advantages of the Invention

[0008] According to the recording head of the present disclosure, breakage of components during bonding can be suppressed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Embodiments for Carrying Out the Invention

[0010] In this specification, in order to facilitate the understanding of the configurations of the inkjet recording apparatus (hereinafter simply referred to as the "recording apparatus") and the recording head according to this embodiment, first, a general recording apparatus and a recording head will be described.

[0011] <General Recording Apparatus> A general recording apparatus 100 (see FIG. 4) can perform high-density and high-speed recording on various recording media S (for example, paper, plastic thin plates, etc.). And in recent years, the recording apparatus 100 hardly generates noise during recording. As a typical ink ejection method of the recording head 1000 mounted on the recording apparatus 100 that hardly generates noise during recording, a method is known in which ink is heated by an electrothermal conversion element 1103 (see FIG. 7) provided with a heating resistor, and ink droplets are ejected by the action of film boiling.

[0012] The recording head 1000 (see FIG. 4) provided with the electrothermal conversion element 1103 has the electrothermal conversion element 1103 provided in a recording liquid chamber (not shown), and an electric pulse serving as a recording signal is supplied to the electrothermal conversion element 1103 to generate heat, thereby giving thermal energy to the ink. In the above method, using the bubble pressure when the ink foams (boils), which is caused by the phase change of the ink when giving thermal energy to the ink, minute ink droplets are ejected from minute ejection ports 1107 (see FIG. 7) to perform recording on the recording medium S. Generally, the recording apparatus 100 includes an inkjet recording nozzle for ejecting ink droplets and a supply system for supplying ink to the nozzle. The recording head 1000 is provided with a nozzle forming material that forms a heater, a substrate on which a matrix wiring and a driver for driving the heater are formed, ejection ports 1107, and the like.

[0013] In addition, to manufacture the recording head 1000, it is necessary to electrically connect the bumps formed on the electrode terminals 1105 on the recording element substrate 1101 (see FIG. 7) and the recording apparatus 100 main body (see FIG. 4). Therefore, the manufacturing process of the recording head 1000 includes a step of electrically connecting the bumps formed on the electrode terminals 1105 (see FIG. 7) and the leads 1304 (see FIG. 3) connected to the recording apparatus 100 main body.

[0014] By the way, in recent years, the number of nozzles has been increasing in order to increase the printing speed. Also, from the viewpoint of reducing the manufacturing cost of the nozzles, the size of the recording element substrate 1101 (see FIG. 7) has been reduced to increase the number of recording element substrates 1101 that can be attached per wafer. Therefore, the number of electrode terminals 1105 (that is, the number of bumps) arranged per wafer tends to increase. According to the plated bumps formed by growing gold by the electrolytic plating method, a plurality of bumps can be formed by batch processing for each wafer, so that variations in the height of the bumps can be suppressed. The above is the description of the general recording apparatus 100 and the recording head 1000.

[0015] <Configuration of General Electrode Terminal 1105> Next, a general electrode terminal 1105 will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic plan view and cross-sectional view of a general electrode terminal 1105. As shown in FIG. 1, in a general electrode terminal 1105, a heat storage layer 202, a first electrical wiring layer 203, an interlayer insulating film 204, a heater film 205, a second electrical wiring layer 206, a protective film 207, and a through hole 200 are sequentially formed on a silicon substrate 201. And a bent portion 212 is formed in the protective film 207.

[0016] Also, on the protective film 207 and the through hole 200, an adhesion improvement layer 208 and a plating conductor gold 209 are sequentially formed in order from below in the figure. Note that the adhesion improvement layer 208 means a barrier metal layer. And a resist 220 (see FIG. 2) is applied on the plating conductor gold 209, and a metal film 210 is formed inside the resist 220.

[0017] <Manufacturing Flow of General Electrode Terminals> Figure 2 is a diagram showing the manufacturing flow of a general electrode terminal 1105. Also, in the following description, "S" means step.

[0018] In S1, on a silicon substrate 201, an IC film (not shown) such as a driver IC, a heat storage layer 202 containing SiO2, and a common electrode (not shown) for supplying power in heater driving by the above driver IC according to a drive signal are formed. The above IC film is configured using a semiconductor element for driving a heater when ink is ejected, and is configured of, for example, about six layers. Also, in the same step, a first electrical wiring layer 203, an interlayer insulating film 204 containing SiO, a heater film 205 constituting a heater, a second electrical wiring layer 206, and a protective film 207 are sequentially formed. The first electrical wiring layer 203 is configured using aluminum that constitutes a common electrode for grounding. Also, the interlayer insulating film 204 covers the entire periphery of the edge of the first electrical wiring layer 203. Also, the second electrical wiring layer 206 contains aluminum for directly connecting to the heater and supplying power. Also, the protective film 207 contains a brittle material such as SiN or SiC for protecting the wiring and the heater. And in the same step, the protective film 207 is patterned by photolithography technology, and a through hole 200 for electrically contacting the aluminum wiring with the outside is formed.

[0019] In S2, an adhesion improvement layer 208 is formed over the entire surface with a predetermined thickness by a vacuum film forming apparatus or the like. For example, as the material of the adhesion improvement layer 208, a high melting point metal material such as TiW can be used. And in the same step, a plating conductor gold 209, which is excellent as a wiring metal, is formed over the entire surface with a predetermined thickness by a vacuum film forming apparatus or the like.

[0020] In S3, a resist 220 is spin-coated on the surface of the plating conductor gold 209, and exposure, development, etc. of the resist 220 are performed using photolithography technology. For example, a negative-type resist 220 can be used as the resist 220. Then, when an electric current is passed through the plating conductor gold 209 by an electrolytic plating method, gold is deposited in the regions not covered by the resist 220, and a thick metal film 210 serving as bumps is formed inside the resist 220.

[0021] In S4, the resist 220 is removed by immersing it in a resist stripping solution for a predetermined time. Then, after the resist 220 is removed and the plating conductor gold 209 is exposed, the plating conductor gold 209 is immersed in an etching solution containing iodine and potassium iodide so as to contain a nitrogen-based organic compound for a predetermined time, and the adhesion improvement layer 208 is exposed.

[0022] In S5, the adhesion improvement layer 208 is immersed in an H2O2-based etching solution for a predetermined time to form a gold plating layer (plating bump) including the plating conductor gold 209 layer for supplying driving power to the aluminum wiring. Note that the adhesion improvement layer 208, the plating conductor gold 209, and the metal film 210 are formed to overlap the entire periphery of the edge of the protective film 207.

[0023] Then, in a subsequent step, the metal film 210 on the recording element substrate 1101 and the lead 1304 are connected. As one of the general methods for connecting the lead 1304 and the recording element substrate 1101, there is a gang bonding method. In the gang bonding method, the leads 1304 are collectively pressure-bonded by thermal pressing and joined to the metal film 210 on the electrode terminal 1105 on the recording element substrate 1101. At this time, since all of the leads 1304 are bonded with a wide bonding tool, according to the gang bonding method, the bonding processing tact can be made substantially the same regardless of the number of leads 1304.

[0024] In the method for manufacturing the recording head 1000 including the step of electrically joining the recording element substrate 1101 and the electrical wiring tape 1301 (see FIG. 5), during the processes such as conveyance and handling until the subsequent step of adhesively fixing to the base member, impacts, vibrations, etc. may occur. Therefore, a certain load is applied to the electrical joint. Regarding these loads, it should be noted that as the size of the recording element substrate 1101 increases, the number of electrode terminals 1105 increases, the size of the electrode terminals 1105 narrows, and the pitch between the arrangements of the electrode terminals 1105 becomes smaller.

[0025] Also, in the gang bonding method, attention should be paid to electrical joint failures such as peeling and breakage. In order to suppress electrical joint failures such as peeling and breakage, temperature control of the bonding tool, which is a condition during bonding, and attention to the impact load when the bonding tool is grounded to the metal film 210 via the lead 1304, etc. are carried out. Furthermore, increasing the pressing load acting after the bonding tool is grounded to the metal film 210 via the lead 1304, improving the bonding strength between the metal film 210 and the lead 1304, etc. are carried out. In FIG. 2, the film state of the electrode terminals 1105 in each process is shown, but it goes without saying that the film structures of the heater, through hole 200, and the entire substrate are simultaneously formed by some of the processes shown in the process of FIG. 2. The above is the description of the general manufacturing flow of the electrode terminals 1105.

[0026] <Regarding the occurrence of crack 222> In the bonding method for electrically joining the metal film 210 and the lead 1304, a pressing force (impact load, pressing load) by the bonding tool is applied to the metal film 210 and the lead 1304. Therefore, the bent portion 212 of the protective film 207 outside the edge of the metal film 210 may be damaged and a crack 222 (see FIG. 3) may be formed. Hereinafter, the process in which the protective film 207 is damaged and the crack 222 is generated will be described.

[0027] Figure 3 is a schematic cross-sectional view of a general electrical joint. As described above, a pressing force is applied to the metal film 210 and the lead 1304 by a bonding tool. Due to the pressing force applied to the metal film 210 by the bonding tool, the lead 1304 and the metal film 210 are crushed.

[0028] In addition, the first electrical wiring layer 203 and the second electrical wiring layer 206 made of aluminum formed under the metal film 210 directly below the lead 1304 are also crushed by the pressing force applied to the metal film 210 by the bonding tool. On the other hand, the heat storage layer 202 and the silicon substrate 201 formed under the first electrical wiring layer 203 are made of materials harder than aluminum. Therefore, the heat storage layer 202 and the silicon substrate 201 are not crushed by the load applied to the metal film 210 by the bonding tool.

[0029] The metal film 210, the first electrical wiring layer 203, and the second electrical wiring layer 206 crushed by the pressing force applied by the bonding tool are moving toward the protective film 207 side located outside the crushed area. At this time, the protective film 207 formed on the upper side of the second electrical wiring layer 206 and the lower side of the metal film 210 and in close contact with the second electrical wiring layer 206 and the metal film 210 is also moving following the movement of the second electrical wiring layer 206 and the metal film 210. As a result, stress concentrates on the bent portion 212 of the protective film 207 located outside the edge of the metal film 210, and cracks 222 may occur in the protective film 207.

[0030] In addition, in order to suppress electrical joint failures such as peeling and breakage, when the pressing force during bonding is increased, the size and the number of cracks 222 generated in the protective film 207 tend to increase. When cracks 222 occur in the bent portion 212 of the protective film 207, moisture such as ink may enter from the cracks 222, and the first electrical wiring layer 203 and the second electrical wiring layer 206 containing aluminum covered by the protective film 207 may corrode. In the manufacturing process of the recording head 1000, the first sealing agent 1307 and the second sealing agent 1308 (see FIG. 5) are applied to the electrical joint to protect the electrical joint from moisture such as ink.

[0031] However, there is a risk that moisture absorbed by the first sealant 1307 and the second sealant 1308 enters through the crack 222 and corrodes the first electrical wiring layer 203 and the second electrical wiring layer 206. The above is the explanation for the occurrence of the crack 222.

[0032] <Inkjet recording apparatus> FIG. 4 is a schematic plan view showing an example of a recording apparatus 100 according to the present embodiment. The recording apparatus 100 according to the present embodiment includes a recording head 1000. The recording head 1000 includes a first recording head 1001 and a second recording head 1002. A carriage 102, a guide shaft 103, a main scanning motor 104, a motor pulley 105, a driven pulley 106, and a timing belt 107 are provided. Further, a home position sensor 108, a shielding plate 109, a paper feed motor 110, a pickup roller 111, an auto sheet feeder 112, a conveyance motor 113, a conveyance roller 114, and a paper end sensor 115 are provided.

[0033] The recording apparatus 100 according to the present embodiment has a carriage 102 that positions and detachably mounts the recording head 1000. The carriage 102 is provided with an electrical junction for transmitting a drive signal or the like to each discharge unit 1108 (see FIG. 7) described later via an external signal connection terminal 1302 on the recording head 1000.

[0034] The carriage 102 is supported so as to be reciprocally movable along a guide shaft 103 that extends in the main scanning direction and is installed on the main body of the recording apparatus 100. The carriage 102 is driven by a main scanning motor 104 via a transmission mechanism such as a motor pulley 105, a driven pulley 106, and a timing belt 107, and its position and movement are controlled. Further, the carriage 102 is provided with a home position sensor 108. When the home position sensor 108 provided in the carriage 102 passes through the position of the shielding plate 109, the position that becomes the home position is detected. The recording medium S is separated and fed one by one from the auto sheet feeder 112 by rotating a pickup roller 111 by a paper feed motor 110 via a gear.

[0035] Furthermore, a conveyance motor 113 drives a conveyance roller 114 via a gear, and the conveyance roller 114 rotates. By the rotation of the conveyance roller 114, the recording medium S is conveyed (sub-scanned) through a position (recording area) facing the surface on which the discharge ports 1107 (see FIG. 7) of the first recording head 1001 and the second recording head 1002 are formed. Hereinafter, the surface on which the discharge ports 1107 are formed is referred to as the "discharge port surface". The determination as to whether or not the recording medium S has been fed and the determination of the leading edge position of the recording medium S at the time of feeding are made when the recording medium S passes through the paper end sensor 115. The paper end sensor 115 is also used to determine where the rear end of the recording medium S actually is and to finally determine the current recording position from the actual rear end. The recording medium S is supported by a platen (not shown) on its back surface so as to form a flat recording surface in the recording area. In this case, the recording head 1000 mounted on the carriage 102 is held such that their discharge port surfaces protrude downward from the carriage 102 and are parallel to the recording medium S, and the recording area is main-scanned.

[0036] The recording head 1000 is mounted on the carriage 102 such that the arrangement direction of the ejection ports 1107 in each ejection unit 1108 intersects the main scanning direction of the carriage 102 (for example, the sub-scanning direction). By ejecting ink from these ejection port arrays during the main scanning process, recording with a width corresponding to the ejection port arrangement range is performed. The recording head 1000 of the present embodiment has an integrated ink tank configuration and includes a first recording head 1001 having an ink storage unit filled with black ink and an ejection unit 1108 that ejects the black ink supplied from this ink storage unit.

[0037] Further, the above-described recording head 1000 includes a second recording head 1002 having ink storage units filled with respective color inks and ejection units 1108 that eject the color inks supplied from the respective ink storage units. Examples of the color inks include cyan ink, magenta ink, yellow ink, and the like. The first recording head 1001 and the second recording head 1002 are fixedly supported on the carriage 102 by positioning means and electrical contacts, and are in the form of a cartridge that is detachable from the carriage 102. And when the filled ink is consumed, the recording head 1000 can be replaced.

[0038] <Configuration of Recording Head 1000> Hereinafter, with reference to FIGS. 5 to 8, the basic configuration of the second recording head 1002 among the recording heads 1000 according to the present embodiment will be described. The first recording head 1001 shown in FIG. 4 has the same configuration as the second recording head 1002 except that it is a configuration for one color of black ink, so the description thereof will be omitted.

[0039] FIG. 5 is a perspective view showing a configuration example of the second recording head 1002 according to the present embodiment. As shown in FIG. 5, the second recording head 1002 includes an electrical wiring tape 1301, an external signal connection terminal 1302, a first sealant 1307, and a second sealant 1308. The second recording head 1002 further includes a mounting guide 1560, a butting portion 1570 in the main scanning direction (X direction), a butting portion 1580 in the sub-scanning direction (Y direction) (see FIG. 5(b)), and a butting portion 1590 in the vertical direction (Z direction). Furthermore, the second recording head 1002 includes an engaging portion 1930 (see FIG. 5(b)).

[0040] FIG. 6 is an exploded perspective view of the second recording head 1002 according to the present embodiment. As shown in the exploded perspective view of FIG. 6, in addition to the configuration shown in FIG. 5, the second recording head 1002 includes a recording element substrate 1101, an opening 1303, a lead 1304, and a main body member 1501 as a support member. The second recording head 1002 further includes a first ink absorber 1601, a second ink absorber 1602, and a third ink absorber 1603. Furthermore, the second recording head 1002 includes a first filter 1701, a second filter 1702, a third filter 1703, a seal member 1801, a lid member 1901, and an engaging portion 1930.

[0041] The second recording head 1002 includes a mounting guide 1560 (see FIG. 5) for guiding it to the mounting position of the carriage 102 of the main body of the recording apparatus 100. The second recording head 1002 is mounted and fixed to the carriage 102 by a fixing lever (not shown) provided on the carriage 102 side. The second recording head 1002 is provided with an engaging portion 1930 for mounting and fixing it to the carriage 102. Further, the second recording head 1002 is provided with a butting portion 1570 in the main scanning direction (X direction), a butting portion 1580 in the sub-scanning direction (Y direction), and a butting portion 1590 in the vertical direction (Z direction) for positioning it at a predetermined mounting position of the carriage 102. The second recording head 1002 is positioned on the carriage 102 by the butting portion 1570 in the main scanning direction, the butting portion 1580 in the sub-scanning direction, and the butting portion 1590 in the vertical direction. Thereby, electrical contact between the external signal connection terminal 1302 on the electrical wiring tape 1301 and the contact pin of the electrical junction portion provided in the carriage 102 is enabled. As described above, the second recording head 1002 can eject three colors of ink, cyan, magenta, and yellow.

[0042] FIG. 7 is a perspective view showing a part of the recording element substrate 1101 broken away. The recording element substrate 1101 according to the present embodiment includes an electrothermal conversion element 1103 that generates thermal energy for causing film boiling to occur in the ink in response to an electrical signal. Further, the electrothermal conversion element 1103 and the discharge port 1107 are arranged so as to face each other, and ink is discharged in a direction perpendicular to the main plane of the recording element substrate 1101. That is, the recording element substrate 1101 according to the present embodiment is a so-called side shooter type substrate.

[0043] As shown in FIG. 7, the recording element substrate 1101 includes a silicon substrate 201. On the silicon substrate 201, an ink supply port 1102, an electrothermal conversion element 1103, an electrode portion 1104, an electrode terminal 1105, an ink flow path wall 1106, a discharge port 1107, a discharge portion 1108, and a discharge port forming member 1109 are provided. In the silicon substrate 201, three long-hole-shaped ink supply ports 1102 for cyan, magenta, and yellow inks are formed in parallel. On both sides of each ink supply port 1102, electrothermal conversion elements H1103 for generating thermal energy to cause film boiling in the ink in response to an electrical signal are arranged in rows. The electrothermal conversion elements 1103 between each row are arranged with a shift of 1 / 2 of the arrangement pitch in the arrangement direction (i.e., the sub-scanning direction).

[0044] Also, the ink flow path wall 1106 and the discharge port 1107 are formed by photolithography technology. And by aligning the positions of the discharge port 1107 and each electrothermal conversion element 1103, discharge portions 1108 of each color are formed. The discharge port forming member 1109 in which the discharge portion 1108 is formed is joined to the recording element substrate 1101. Also, on the silicon substrate 201, electrical wirings made of aluminum or the like for supplying power to the electrothermal conversion element 1103, fuses, and electrothermal conversion elements 1103 are formed according to recording data. Also, a logic circuit for driving the recording device 100 and an electrode portion 1104 or the like for electrically connecting these parts to the outside are formed. Further, electrode terminals 1105 in the form of plating bumps made of Au or the like are formed on the electrode portion 1104. Note that the electrothermal conversion element 1103 and the like can be formed using existing film formation technologies.

[0045] The electrical wiring tape 1301 (see Fig. 6), which is an electrical wiring member, forms an electrical signal path for applying an electrical signal for discharging ink to the recording element substrate 1101. An opening 1303 (see Fig. 6) for incorporating the recording element substrate 1101 is formed in the electrical wiring tape 1301, and a lead 1304 connected to the electrode portion 1104 of the recording element substrate 1101 protrudes from the edge of the opening 1303. Further, an external signal connection terminal 1302 for receiving an electrical signal from the main body of the recording apparatus 100 is formed in the electrical wiring tape 1301, and the lead 1304 and the external signal connection terminal 1302 are connected by a conductive wiring pattern including a continuous copper foil or the like.

[0046] Here, the electrical wiring tape 1301 is formed using a TAB tape. On the other hand, the lead 1304 is exposed and serves as a flying lead. Regarding the connection between the electrical wiring tape 1301 and the recording element substrate 1101, the metal film 210 formed on the electrode terminal 1105 and the lead 1304 of the electrical wiring tape 1301 corresponding to the electrode terminal 1105 are electrically joined by a gang bonding method.

[0047] Fig. 8 is a partial cross-sectional view of the recording head 1000 showing the sealed state of the electrical joint. As shown in Fig. 8, the electrical joint portion between the recording element substrate 1101 and the electrical wiring tape 1301 is sealed by a first sealing agent 1307 and a second sealing agent 1308. Therefore, the electrical joint portion can be protected from corrosion by moisture such as ink and external impact. The first sealing agent 1307 mainly seals the back side of the connection portion between the lead 1304 of the electrical wiring tape 1301 and the electrode terminal 1105 of the recording element substrate 1101 and the outer peripheral portion of the recording element substrate 1101. The second sealing agent 1308 seals the front side of the electrical joint portion.

[0048] <Configuration of the electrode terminal 1105 according to the present embodiment> The configuration of the electrode terminal 1105 according to this embodiment will be described with reference to the drawings. Note that even when examples are shown and described, the technology according to the present disclosure is not limited to these examples in any way. Further, even with respect to the configurations of the recording device 100 and the recording head 1000 according to this embodiment, the same names and the same reference numerals will be used to describe the same or corresponding configurations as those of a general recording device 100 and recording head 1000.

[0049] FIG. 9 shows a cross-section of the substrate of the electrode terminal 1105 according to this embodiment and a schematic diagram of the upper surface of the electrode terminal 1105. On a silicon substrate 201, a heat storage layer 202, a first electrical wiring layer 203, an interlayer insulating film 204, a heater film 205, a second electrical wiring layer 206, and a protective film 207 are sequentially laminated. The interlayer insulating film 204 is formed so as to cover the entire periphery of the edge of the first electrical wiring layer 203. Then, the protective film 207 is opened by patterning, and a through hole 200 for electrically contacting the external electrical wiring is formed. A thick film of gold serving as a bump (hereinafter referred to as "metal film 210") is formed by an electrolytic plating method via an adhesion improvement layer 208 such as TiW formed as an underlayer and a plating conductor gold 209 in the through hole 200. The shape of the metal film 210 is substantially rectangular in plan view. Further, the metal film 210 is electrically connected to the first electrical wiring layer 203 and the second electrical wiring layer 206. That is, the first electrical wiring layer 203 and the second electrical wiring layer 206 are formed below the metal film 210 and are electrically connected to the metal film 210.

[0050] In this embodiment, before forming the gold plating bumps (i.e., the metal film 210), a groove 221 is formed to divide the protective film 207, the first electrical wiring layer 203, and the second electrical wiring layer 206 around the electrical junction portion, and a resin film 211 is embedded in the groove 221. That is, the groove 221 divides the protective film 207, the first electrical wiring layer 203, and the second electrical wiring layer 206 around the metal film 210. And a resin film 211 is embedded in the groove 221. When the bent portion 212 of the protective film 207 is exposed like a general electrode terminal 1105 (see FIG. 3), cracks 222 may occur in the bent portion 212 when the leads 1304 are joined together by the gang bonding method.

[0051] However, according to the electrode terminal 1105 according to this embodiment, even when pressure is applied to the metal film 210 by bonding, the groove 221 formed suppresses the movement of the first electrical wiring layer 203 and the second electrical wiring layer 206 following the movement of the metal film 210. Therefore, the stress applied to the protective film 207 can be relaxed.

[0052] Therefore, since the deformation of the first electrical wiring layer 203 and the second electrical wiring layer 206 is suppressed, the bending of the protective film 207 is also suppressed, and the occurrence of cracks 222 can be suppressed. Further, even if cracks 222 occur in the protective film 207, the resin film 211 is embedded in the groove 221, and the portion where the cracks 222 occur is protected by the resin film 211. Therefore, it is possible to suppress the problem that moisture such as ink enters from the cracks 222 and the aluminum wiring corrodes. Also, it is possible to suppress the problem that the aluminum wiring corrodes due to the moisture absorbed by the first sealing agent 1307 and the second sealing agent 1308.

[0053] <Method for forming the electrode terminal 1105 according to this embodiment> Subsequently, a method for forming the electrode terminal 1105 according to this embodiment will be described with reference to FIG. 10. FIG. 10 is a diagram showing the manufacturing flow of the electrode terminal 1105 according to this embodiment.

[0054] Regarding the same or corresponding configurations as the general electrode terminal 1105 described above with reference to FIG. 2, the description will be omitted as appropriate.

[0055] In S1, the above-mentioned IC film (not shown), the above-mentioned heat storage layer 202, the above-mentioned first electrical wiring layer 203, the above-mentioned interlayer insulating film 204, the above-mentioned heater film 205, the above-mentioned second electrical wiring layer 206, and the above-mentioned protective film 207 are sequentially laminated from below on the silicon substrate 201. That is, in this step, the first electrical wiring layer 203 and the second electrical wiring layer 206 that are electrically connected to the metal film 210 are formed. That is, this step includes a process of forming the first electrical wiring layer 203 formed below the metal film 210 and electrically connected to the metal film 210, and the second electrical wiring layer 206. Then, the protective film 207 is patterned by photolithography technology, and a through hole 200 for electrically contacting the aluminum wiring with the outside is formed. Further, in the present embodiment, after patterning the protective film 207, similarly by photolithography technology, a groove 221 for dividing the protective film 207 and the first electrical wiring layer 203 and the second electrical wiring layer 206 around the electrical junction portion that are laminated is formed. That is, the groove 221 is formed by photolithography.

[0056] In S2, the above-mentioned adhesion improvement layer 208 is formed into a film with a predetermined thickness over the entire surface by a vacuum film forming apparatus or the like. Then, a plating conductor gold 209, which is excellent as a wiring metal, is formed into a film with a predetermined thickness over the entire surface by a vacuum film forming apparatus or the like.

[0057] In S3, a resist 220 is applied to the surface of the plating conductor gold 209 by a spin coating method. For example, a negative resist 220 can be used.

[0058] In S4, exposure, development, etc. of the resist 220 are performed by photolithography technology.

[0059] In S5, by the electrolytic plating method, when a predetermined current is passed through the plating conductor gold 209, gold is deposited in a predetermined area not covered by the resist 220, and a thick metal film 210 serving as a bump is formed inside the resist 220.

[0060] In S6, the resist 220 is removed by immersing it in a resist stripping solution for a predetermined time, and the plating conductor gold 209 is exposed.

[0061] In S7, the plating conductor gold 209 is immersed in an etching solution containing iodine and potassium iodide containing a nitrogen-based organic compound for a predetermined time to remove the plating conductor gold 209 by etching. Then, the adhesion improvement layer 208 is immersed in an H2O2-based etching solution for a predetermined time, so that a plating bump for supplying driving power to the aluminum wiring is formed of a gold plating layer made of the plating conductor layer.

[0062] In S8, a resin film 211 is applied to the surface of the protective film 207 by the spin coating method, and the resin film 211 is heated and cured. As the material of the resin film 211, a polyether amide resin, an acrylic resin, a cyclized rubber, an epoxy resin, etc. can be used. For example, a negative-type resist 220 is applied to the surface of the resin film 211 by the spin coating method, and the resist 220 is exposed and developed by photolithography technology for patterning. At this time, as shown in the figure of S8, the resin film 211 is formed so as to be embedded in a groove 221 that divides the protective film 207, the first electrical wiring layer 203, and the second electrical wiring layer 206 around the electrical junction. Also, the resin film 211 is arranged so as to cover the protective film 207 around the electrical junction.

[0063] FIG. 11 is a diagram showing the process sequence of a general electrode terminal 1105 and the process sequence of the electrode terminal 1105 according to the present embodiment. As shown in FIG. 11, the general process sequence is in the order of a recording element formation process, an adhesion improvement layer formation process, a gold plating formation process, and a resin film formation process. On the other hand, the process sequence of the present embodiment is in the order of a recording element formation process, a dividing groove formation process, an adhesion improvement layer formation process, a gold plating formation process, and a resin film formation process. That is, the difference from the general process sequence is that a dividing groove formation process is added after the recording element formation process.

[0064] <Formation position of groove 221> FIG. 12 is a diagram showing an example of the formation position of groove 221. FIG. 12(a) is a schematic plan view of an electrical joint according to the present embodiment. FIG. 12(b) is a cross-sectional view taken along line XIIb-XIIb of FIG. 12(a). FIG. 12(c) is a cross-sectional view taken along line XIIc-XIIc of FIG. 12(a). As shown in FIG. 12(a), by forming groove 221 around the electrical joint, it is possible to relieve the stress during bonding and suppress the occurrence of crack 222 in protective film 207. On the other hand, in order to ensure electrical connection, it is necessary to secure a region where groove 221 is not formed partially. In other words, on protective film 207, the formation position of groove 221 is not limited as long as it does not surround the entire circumference of the electrical joint with groove 221. For example, as shown in FIG. 12(b), an example of securing a region where groove 221 is not formed on the short side of the electrical joint can be cited. In the example shown in FIG. 12(a), the electrical joint is designed in a rectangular shape, and the long side is in a state without margin compared to the short side of metal film 210. Therefore, when leads 1304 are joined together using the gang bonding method, crack 222 easily enters bent portion 212 of protective film 207 outside the long side edge of metal film 210. Therefore, it is preferable to arrange groove 221 so as to cover the long side of the electrical joint where crack 222 easily enters protective film 207.

[0065] <Modification example> In Embodiment 1, an example was shown in which the groove 221 was formed so as to entirely cover the longitudinal side of the electrical joint portion. However, the formation position of the groove 221 is not limited to this example. Hereinafter, a modified example of Embodiment 1 will be described with reference to the drawings. In the following description, for the same configurations as those in Embodiment 1, the same reference numerals will be given and the description will be omitted, and the description will focus on the differences. In this modified example, it is preferable to limit the formation regions of the groove 221 and the resin film 211 in consideration of various phenomena caused by the decrease in the fluidity of the first sealant 1307 and the second sealant 1308. Examples of the various phenomena described above include the aforementioned decrease in electrical reliability and printing defects caused by the decrease in the fluidity of the second sealant 1308.

[0066] First, the decrease in electrical reliability will be described. In a general electrode terminal 1105, the second sealant 1308 is applied onto the protective film 207. In contrast, in the present embodiment, the second sealant 1308 is applied both onto the protective film 207 and onto the resin film 211. At this time, the adhesion between the protective film 207 and the second sealant 1308 is greater than the adhesion between the resin film 211 and the second sealant 1308. For this reason, the second sealant 1308 applied onto the resin film 211 is more likely to flow than when it is applied onto the protective film 207. As a result, there is a risk of causing a decrease in electrical reliability because the protection of the electrical joint portion by the second sealant 1308 is insufficient. The above is the explanation of the decrease in electrical reliability. Subsequently, the printing defects will be described. There is a risk of causing printing defects such as paper jams due to an increase in the height of the second sealant 1308 from the recording element substrate 1101. The above is the explanation of the printing defects. Therefore, it is better not to form the groove 221 and the resin film 211 directly under the lead 1304. That is, it is preferable to limit the formation regions of the groove 221 and the resin film 211.

[0067] FIG. 13 is a diagram showing an example of the formation position of the groove 221. FIG. 13(a) is a diagram showing an example of forming the groove 221 at a position that does not cover all of both sides on the longitudinal side in the longitudinal direction of the electrical joint. According to the electrical joint according to this modification, the formation distance of the groove 221 can be made shorter than that of the electrical joint according to Embodiment 1. FIG. 13(b) is a diagram showing an example of intermittently forming the groove 221 outside both sides on the longitudinal side in the longitudinal direction of the electrical joint. According to the electrical joint according to this modification, the formation distance of the groove 221 can be made even shorter than that of the electrical joint shown in FIG. 13(a). FIG. 13(c) is a diagram showing an example of continuously forming the groove 221 on one side of the electrical joint in either the longitudinal direction or the short-side direction. That is, FIG. 13(c) is a diagram showing an example of forming the groove 221 in a "U-shape". When forming the groove 221 in a "U-shape", the groove 221 is formed outside either one of the two sides in the short-side direction of the metal film 210. According to the electrical joint according to this modification, the region for releasing the stress during bonding can be made wider than that of the electrical joint according to Embodiment 1. FIG. 13(d) is a diagram showing an example of continuously forming the groove 221 on one side at the other end side different from the example shown in FIG. 13(c) among the longitudinal direction and the short-side direction of the electrical joint. That is, FIG. 13(d) is a diagram showing an example of forming a "U-shaped" groove 221 in the direction opposite to that shown in FIG. 13(c). According to the electrical joint according to this modification, similar to the example shown in FIG. 13(c), the region for releasing the stress during bonding can be made wider than that of the electrical joint according to Embodiment 1. Note that when the electrical joint is circular or elliptical, forming the groove 221 in a "C-shape" can obtain the same effect as when forming the above-described "U-shaped" groove 221.

[0068] <Other Embodiments> Incidentally, on the recording element substrate 1101, an ink flow path wall 1106, a discharge port forming member 1109 that forms a discharge port 1107, etc. are aligned and joined. In order to enhance the adhesion during this joining, an adhesion improvement layer 208 may be provided on the recording element substrate 1101. The adhesion improvement layer 208 can be used also as a resin film 211 to be embedded in a groove 221 around an electrical junction portion. When the adhesion improvement layer 208 is also used as the resin film 211 to be embedded in the groove 221, an increase in the number of steps caused by separately arranging the resin film 211 can be avoided. As described above, even when pressure is applied to the metal film 210 by bonding, the stress escapes into the groove 221, so that the metal film 210 does not move following the movement, and the pressure during bonding can be relaxed. Therefore, deformation of the first electrical wiring layer 203 and the second electrical wiring layer 206 is suppressed, stress does not concentrate on the bent portion 212 of the protective film 207, and generation of cracks 222 in the protective film 207 can be suppressed. In the bonding according to the present embodiment, the gang bonding method is used, but single point bonding may also be used.

[0069] Also, in the technique of the present disclosure, in the manufacturing process of the recording apparatus 100, the step of electrically joining the recording element substrate 1101 and the electrical wiring substrate may be performed in advance. Further, the recording element substrate 1101 and the electrical wiring substrate may be each fixed to the base member alone first and then the two may be electrically joined.

[0070] Furthermore, in the first embodiment, an example in which the technique of the present disclosure is applied to the configuration of the second recording head 1002 for color that discharges three colors of cyan, magenta, and yellow inks has been described. However, the technique of the present disclosure may be applied to the first recording head 1001 for black ink. Also, the type, number, etc. of the color tones (color and density) of the inks used in the recording head 1000 may be changed as appropriate.

[0071] In addition, in Embodiment 1, the case where the technology of the present disclosure is applied to the recording head 1000 in which the ink storage unit is integrally formed inseparably is exemplified. However, from the viewpoint of alleviating the load on the electrode terminal 1105, the protective film 207, etc., it may be applied to a form of the recording head 1000 in which the ink tank is integrally formed separably or is separate from the ink tank.

Explanation of Signs

[0072] 203 First electrical wiring layer 206 Second electrical wiring layer 207 Protective film 210 Metal film 211 Resin film 221 Groove

Claims

1. A recording head comprising a metal film formed on a stacked layer, An electrical wiring layer formed below the metal film and electrically connected to the metal film, A protective film covering and protecting the electrical wiring layer, A groove for dividing the protective film and the electrical wiring layer around the metal film, A resin film applied to the groove, and comprising A recording head characterized by the above.

2. The resin film is formed on the surface of the protective film, The recording head according to claim 1, characterized by the above.

3. The resin film contains at least one or more of polyether amide resin, acrylic resin, cyclized rubber, and epoxy resin, The recording head according to claim 1 or 2, characterized by the above.

4. A lead joined to the metal film, and comprising The recording head according to any one of claims 1 to 3, characterized by the above.

5. The groove is formed by photolithography, The recording head according to any one of claims 1 to 4, characterized by the above.

6. The groove is filled with the resin film, A resin film obtained by curing the resin film is formed on the protective film, The recording head according to any one of claims 1 to 5, characterized by the above.

7. The shape of the metal film is substantially rectangular in plan view, The groove is formed without surrounding the entire circumference of the metal film, The recording head according to any one of claims 1 to 6, characterized by the above.

8. The groove is continuously formed outside both sides in the longitudinal direction of the metal film. The recording head according to claim 7, characterized in that.

9. The groove is intermittently formed outside both sides in the longitudinal direction of the metal film. The recording head according to claim 7, characterized in that.

10. The groove is formed outside either one of the two sides in the short side direction of the metal film. The recording head according to any one of claims 7 to 9, characterized in that.

11. A method for manufacturing a recording head including a metal film formed on a laminated layer, Forming an electrical wiring layer formed below the metal film and electrically connected to the metal film; Forming a protective film that covers and protects the electrical wiring layer; Forming a groove that divides the protective film and the electrical wiring layer around the metal film; Applying a resin to the groove; including A method for manufacturing a recording head, characterized in that.

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