JP2016043516A

JP2016043516A - Method for manufacturing liquid discharge head

Info

Publication number: JP2016043516A
Application number: JP2014167745A
Authority: JP
Inventors: 正久渡部; Masahisa Watabe; 小林　順一; Junichi Kobayashi; 順一小林; 謙児藤井; Kenji Fujii; 純山室; Jun Yamamuro; 浅井　和宏; Kazuhiro Asai; 和宏浅井; 弘司笹木; Hiroshi Sasaki; 松本　圭司; Keiji Matsumoto; 圭司松本; 邦仁魚橋; Kunihito Uohashi; 誠一郎柳沼
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 2014-08-20
Filing date: 2014-08-20
Publication date: 2016-04-04

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid discharge head with high yield.SOLUTION: A method for manufacturing a liquid discharge head includes: (1) a step of preparing a substrate which has a liquid discharge energy generating element on a first surface, and a liquid supply passage passing from the first surface to a second surface in an opposite side to the first surface; (2) a step of forming a laminated structure of two or more layers including a first photosensitive resin layer, and a second photosensitive resin layer including an outermost layer having a softening point lower than that of the first photosensitive resin layer; (3) a step of joining the laminated structure onto the first surface of the substrate so that the outermost layer of the second photosensitive resin layer of the laminated structure is brought into contact with the first surface; (4) a step of forming a second layer which exposes the laminated structure and specifies a liquid flow channel in the second photosensitive resin layer, and a first layer which specifies a discharge port in the first photosensitive resin layer.SELECTED DRAWING: Figure 3

Description

本技術は、液体吐出ヘッドの製造方法に関する。 The present technology relates to a method for manufacturing a liquid discharge head.

従来、液体吐出ヘッドの製造方法としては、ドライフィルムを用いて形成する方法が知られている。例えば、特許文献１に記載の方法では、まず、第１面に液体吐出エネルギー発生素子と配線とを有する基板の上に、感光性樹脂を含有する流路側壁形成層を形成し露光する。流路側壁形成層の上に感光性樹脂を含有する吐出口形成層を形成し、露光、現像することで、流路や吐出口を形成する。最後に第１面と反対の第２面から基板に液体供給路を形成している。各層を形成する際に、ドライフィルムを用いて積層している。 Conventionally, as a method of manufacturing a liquid discharge head, a method of forming using a dry film is known. For example, in the method described in Patent Document 1, first, a flow path sidewall forming layer containing a photosensitive resin is formed and exposed on a substrate having a liquid ejection energy generating element and wiring on the first surface. A discharge port forming layer containing a photosensitive resin is formed on the flow channel side wall forming layer, and the flow channel and the discharge port are formed by exposure and development. Finally, a liquid supply path is formed in the substrate from the second surface opposite to the first surface. When forming each layer, it laminates | stacks using the dry film.

また、特許文献２には、液体流路と吐出口とをそれぞれ異なるフィルムを用いて形成する方法が記載されている。まず、基板上に流路を規定する感光性材料の層と別の感光性材料の接着層とを有する第1フィルム部材を積層し、フォトリソグラフィー技術により一括して流路パターンを形成する。次に第1フィルム部材上に、感光性材料の吐出口を規定する層と感光性かつ撥水性の撥水層を含む第２フィルム部材を積層し、フォトリソグラフィー技術により一括して吐出口パターンを形成している。 Patent Document 2 describes a method of forming a liquid channel and a discharge port using different films. First, a first film member having a photosensitive material layer that defines a flow path and an adhesive layer of another photosensitive material is laminated on a substrate, and a flow path pattern is collectively formed by a photolithography technique. Next, on the first film member, a second film member containing a photosensitive material discharge port and a photosensitive and water-repellent water-repellent layer are laminated, and the discharge port pattern is collectively formed by photolithography. Forming.

特開２０１３−０１８２７２号公報JP 2013-018272 A 米国特許８５００２４６号US Patent No. 8500466

しかしながら、通常、ドライフィルムは、ベースフィルム上に感光性樹脂（フォトレジスト）層が形成されており、フォトレジスト層を基板に貼り付けた後、ベースフィルムを剥離する必要がある。特許文献１の方法では、基板を貫通する液体供給路を最後に形成するため、ドライフィルムからベースフィルムを剥離する際には何ら問題はない。但し、特許文献１の方法では、基板を貫通する液体供給路は第２面側から形成する必要がある。そのため、多数個取りを行うウエハプロセスにおいては、液体供給路の第１面側開口面積が変動し、オーバーエッチングにより第１面側の液体流路を含む構造にまでエッチングの影響を及ぼす可能性があり、更なる改良が求められる。他方、特許文献２に開示されたように予め液体供給路等を形成した穴あき基板にドライフィルムを貼り付けた後、ベースフィルムを剥離すると、剥離時に、ノズルクラックなどの不良が発生し歩留まりが低下する懸念がある。具体的には、図５（ａ）及び（ｂ）に示すように、第１レジスト５２の単層ドライフィルムまたは第１レジスト５２および第２レジスト５３を有する複層ドライフィルムを液体供給路１１の形成された基板１上に貼り付け、ベースフィルム５１を剥離すると、接着面のない液体供給路１１の部分のレジスト材料がベースフィルム側に付着したまま引き剥がされ、フィルム面の平滑性が損なわれる。また、プロセスによる対応をしても、密着不足等による歩留まり低下が懸念される。さらに特許文献２のように接着層と流路規定層の積層からなる第１フィルム部材を流路パターンにパターニングした後、残存する流路規定層上に吐出口を形成する第２フィルム部材を橋渡しするように貼り合わせるプロセスは、気泡や割れなどが発生しやすいため、歩留りが低下する可能性がある。 However, in general, a dry film has a photosensitive resin (photoresist) layer formed on a base film, and it is necessary to peel off the base film after the photoresist layer is attached to a substrate. In the method of Patent Document 1, since the liquid supply path that penetrates the substrate is formed last, there is no problem when the base film is peeled from the dry film. However, in the method of Patent Document 1, it is necessary to form the liquid supply path that penetrates the substrate from the second surface side. For this reason, in a wafer process in which a large number of wafers are taken, the opening area on the first surface side of the liquid supply path fluctuates, and overetching may affect the structure including the liquid flow path on the first surface side. There is a need for further improvements. On the other hand, when a base film is peeled off after a dry film is pasted on a perforated substrate on which a liquid supply path or the like has been previously formed as disclosed in Patent Document 2, defects such as nozzle cracks occur at the time of peeling, resulting in a high yield. There are concerns about a decline. Specifically, as shown in FIGS. 5A and 5B, a single-layer dry film of the first resist 52 or a multilayer dry film having the first resist 52 and the second resist 53 is removed from the liquid supply path 11. When the base film 51 is peeled off and pasted on the formed substrate 1, the resist material in the portion of the liquid supply path 11 having no adhesive surface is peeled off while adhering to the base film side, and the smoothness of the film surface is impaired. . In addition, even if a process is used, there is a concern that the yield may decrease due to insufficient adhesion. Further, after patterning the first film member made of a laminate of the adhesive layer and the flow path defining layer into a flow path pattern as in Patent Document 2, the second film member that forms the discharge port on the remaining flow path defining layer is bridged. In the process of bonding, the yield tends to decrease because bubbles or cracks are likely to occur.

そこで、本発明は、歩留り良く液体吐出ヘッドを製造する方法を提供することを目的とする。 SUMMARY An advantage of some aspects of the invention is to provide a method of manufacturing a liquid discharge head with high yield.

本発明によれば、液体吐出ヘッドの製造方法であって、
（１）第１面に液体吐出エネルギー発生素子を有し、第１面から反対の第２面に貫通する液体供給路を有する基板を準備する工程と、
（２）第一の感光性樹脂層と、前記第一の感光性樹脂層よりも軟化点の低い最外層を含む第二の感光性樹脂層を備える２層以上の積層構造体を形成する工程と、
（３）前記基板の第１面上に、前記積層構造体を、前記積層構造体の前記第二の感光性樹脂層の最外層を接触させて接合する工程と、
（４）前記積層構造体を露光し、前記第二の感光性樹脂層に液体流路を規定する第二の層を、前記第一の感光性樹脂層に吐出口を規定する第一の層を、それぞれ形成する工程と、
を含むことを特徴とする液体吐出ヘッドの製造方法、が提供される。 According to the present invention, there is provided a method for manufacturing a liquid discharge head,
(1) preparing a substrate having a liquid discharge energy generating element on the first surface and having a liquid supply path penetrating from the first surface to the opposite second surface;
(2) A step of forming a laminated structure of two or more layers including a first photosensitive resin layer and a second photosensitive resin layer including an outermost layer having a softening point lower than that of the first photosensitive resin layer. When,
(3) bonding the laminated structure on the first surface of the substrate by bringing the outermost layer of the second photosensitive resin layer of the laminated structure into contact with each other;
(4) Exposing the laminated structure, the second layer defining a liquid flow path in the second photosensitive resin layer, and the first layer defining an ejection port in the first photosensitive resin layer Forming each of the above,
A method for manufacturing a liquid discharge head is provided.

本発明によれば、歩留まり良く液体吐出ヘッドを製造することが可能となる。 According to the present invention, it is possible to manufacture a liquid discharge head with high yield.

本発明の実施形態に係る液体吐出ヘッドの１例を示す斜視模式図である。FIG. 3 is a schematic perspective view illustrating an example of a liquid ejection head according to an embodiment of the present invention. 本発明の実施形態に係る積層構造体の製造方法を示す断面模式図である。It is a cross-sectional schematic diagram which shows the manufacturing method of the laminated structure which concerns on embodiment of this invention. 本発明の実施形態に係る液体吐出ヘッドの製造方法を示す断面模式図である。It is a cross-sectional schematic diagram which shows the manufacturing method of the liquid discharge head which concerns on embodiment of this invention. 本発明の実施形態に係る積層構造体の他の１例を示す断面模式図である。It is a cross-sectional schematic diagram which shows another example of the laminated structure which concerns on embodiment of this invention. 従来の液体吐出ヘッドの製造方法の課題を示す断面図である。It is sectional drawing which shows the subject of the manufacturing method of the conventional liquid discharge head.

図１は、本発明の実施形態に係る液体吐出ヘッドの一例を示す斜視模式図である。図１に示す液体吐出ヘッドは、第１面１Ａ上に液体吐出エネルギー発生素子２が所定のピッチで２列並んで配置されている基板１を有する。液体吐出エネルギー発生素子２の列間には、基板１を第１面１Ａから第２面１Ｂに貫通する液体供給路１１が形成されている。基板１の第１面１Ａ上には、不図示のポリエーテルアミド層等の密着層を介して吐出口形成部材３が形成されている。吐出口形成部材３は、液体流路１２を規定する第二の層１５と、吐出口１３を規定する第一の層１４とを含んで構成されている。液体流路１２は、液体供給路１１から各吐出口１３に連通し、液体供給路１１から液体流路１２内に充填された液体に、液体吐出エネルギー発生素子２によって液体を吐出するエネルギーが与えられると、吐出口１３から液滴を吐出する。この液滴を記録媒体に被着させることによって、記録を行う。 FIG. 1 is a schematic perspective view illustrating an example of a liquid discharge head according to an embodiment of the present invention. The liquid discharge head shown in FIG. 1 has a substrate 1 on which liquid discharge energy generating elements 2 are arranged in two rows at a predetermined pitch on a first surface 1A. A liquid supply path 11 that penetrates the substrate 1 from the first surface 1A to the second surface 1B is formed between the rows of the liquid discharge energy generating elements 2. On the first surface 1A of the substrate 1, a discharge port forming member 3 is formed via an adhesion layer such as a polyetheramide layer (not shown). The discharge port forming member 3 includes a second layer 15 that defines the liquid flow path 12 and a first layer 14 that defines the discharge port 13. The liquid flow path 12 communicates with each discharge port 13 from the liquid supply path 11, and gives energy for discharging the liquid by the liquid discharge energy generating element 2 to the liquid filled in the liquid flow path 12 from the liquid supply path 11. Then, a droplet is discharged from the discharge port 13. Recording is performed by depositing these droplets on a recording medium.

液体を吐出するエネルギーを発生する液体吐出エネルギー発生素子２としては、例えば電気−熱変換体により液体に膜沸騰を生じさせ気泡を形成することで液滴を吐出する形態、電気−機械変換体によって液滴を吐出する形態、静電気を利用して液滴を吐出する形態等がある。液体吐出技術で提案される各種記録方式をいずれも用いることができる。中でも特に高速で高密度の記録の観点からは、液体吐出エネルギー発生素子２として電気−熱変換体を利用したものが好適に用いられる。液体吐出エネルギー発生素子２は、通常、不図示の絶縁膜で保護されている。また、基板１の第一の面１Ａ上には、液体吐出エネルギー発生素子２への電力を供給する配線（不図示）が形成され、さらに、各種回路が形成されていてもよい。 As the liquid discharge energy generating element 2 that generates energy for discharging the liquid, for example, an electro-mechanical converter may be used to discharge liquid droplets by causing film boiling in the liquid by an electro-thermal converter and forming bubbles. There are a form of ejecting droplets, a form of ejecting droplets using static electricity, and the like. Any of the various recording methods proposed in the liquid ejection technique can be used. In particular, from the viewpoint of high-speed and high-density recording, the liquid discharge energy generating element 2 using an electro-thermal converter is preferably used. The liquid discharge energy generating element 2 is usually protected by an insulating film (not shown). Further, on the first surface 1A of the substrate 1, wiring (not shown) for supplying power to the liquid ejection energy generating element 2 may be formed, and various circuits may be formed.

次に、図２、図３を用いて、図１に示す液体吐出ヘッドの製造方法について説明する。図２は本発明に用いることができる積層構造体の製造方法の一例を説明するための図である。図３は本実施形態の液体吐出ヘッドの製造方法の一例を説明するための図であり、図１のＡ−Ａ’における断面を示す図である。 Next, a method for manufacturing the liquid discharge head shown in FIG. 1 will be described with reference to FIGS. FIG. 2 is a diagram for explaining an example of a method for manufacturing a laminated structure that can be used in the present invention. FIG. 3 is a view for explaining an example of the manufacturing method of the liquid discharge head of the present embodiment, and is a view showing a cross section taken along line A-A ′ of FIG. 1.

まず、図２（ａ）に示すように、ベースとなるフィルム２１上に吐出口を規定する第一の層１４となる第一の感光性樹脂層１４Ａをスピンコート、スリット塗布等により形成する。ベースとなるフィルム２１は、ポリイミド、ＰＥＴ、ＥＴＦＥ、ＰＶＡ等が挙げられる。第一の感光性樹脂層１４Ａに用いる第一の感光性樹脂としては、ネガ型感光性樹脂が好ましく、エポキシ樹脂、アクリル樹脂、ウレタン樹脂、ポリイミド樹脂、ポリアミド樹脂等が挙げられる。これらの１種または２種以上の組合せを用いることができる。なお、第一の感光性樹脂層１４Ａに用いるネガ型感光性樹脂は、流路を規定する第二の層１５となる第二の感光性樹脂層１５Ａを硬化させずに選択的に吐出口１３を形成できる感光感度、感光波長等を持つ材料を用いることが好ましい。第一の感光性樹脂層１４Ａの厚みは、第二の感光性樹脂層１５Ａの厚み以下の、１μｍ〜５０μｍであることが好ましい。また、第一の感光性樹脂層１４Ａは、第二の感光性樹脂層１５Ａよりも厚く形成し、積層構造体２２の剛性を維持しながら基板１に貼り付けた後、所望の厚みに研磨することで歩留りを向上させる効果が得られる。この場合は研磨後の所望膜厚に１μｍ〜１００μｍを足した厚みが好ましく、研磨プロセスの時間短縮によるコストダウンを考慮すると研磨後の所望膜厚に１μｍ〜３０μｍを足した厚みを研磨前の厚みとすることがさらに好ましい。 First, as shown in FIG. 2A, a first photosensitive resin layer 14A to be a first layer 14 that defines a discharge port is formed on a base film 21 by spin coating, slit coating, or the like. Examples of the base film 21 include polyimide, PET, ETFE, and PVA. The first photosensitive resin used for the first photosensitive resin layer 14A is preferably a negative photosensitive resin, and examples thereof include an epoxy resin, an acrylic resin, a urethane resin, a polyimide resin, and a polyamide resin. One or a combination of two or more of these can be used. The negative photosensitive resin used for the first photosensitive resin layer 14A is selectively discharged from the discharge port 13 without curing the second photosensitive resin layer 15A to be the second layer 15 that defines the flow path. It is preferable to use a material having a photosensitivity, a photosensitivity wavelength, and the like that can form the film. The thickness of the first photosensitive resin layer 14A is preferably 1 μm to 50 μm, which is equal to or less than the thickness of the second photosensitive resin layer 15A. The first photosensitive resin layer 14A is formed to be thicker than the second photosensitive resin layer 15A, and is bonded to the substrate 1 while maintaining the rigidity of the laminated structure 22, and then polished to a desired thickness. Thus, the effect of improving the yield can be obtained. In this case, a thickness obtained by adding 1 μm to 100 μm to the desired film thickness after polishing is preferable. In consideration of cost reduction due to shortening of the polishing process time, a thickness obtained by adding 1 μm to 30 μm to the desired film thickness after polishing is a thickness before polishing. More preferably.

次に、図２（ｂ）に示すように、第二の感光性樹脂層１５Ａをスピンコート、スリット塗布等により形成する。第二の感光性樹脂層１５Ａの厚みは５μｍ〜２００μｍが好ましい。第二の感光性樹脂層１５Ａに用いる第二の感光性樹脂としては、ネガ型感光性樹脂が好ましく、エポキシ樹脂、アクリル樹脂、ウレタン樹脂、ポリイミド樹脂、ポリアミド樹脂等が挙げられる。これらの１種または２種以上の組合せを用いることができる。第一の感光性樹脂層１４Ａに用いる第一の感光性樹脂に対し、第二の感光性樹脂には軟化点が低い感光性樹脂を使用する。接合時の加熱の際に、第一の感光性樹脂層１４Ａを維持し、第二の感光性樹脂層１５Ａを軟化させ、密着性を良化させるために、第一の感光性樹脂と、第二の感光性樹脂の軟化点は１０℃以上離れていることが好ましい。第一の感光性樹脂は軟化点４０℃〜９０℃、第二の感光性樹脂層は軟化点３０℃〜８０℃であることが好ましい。流路を形成する際、第二の感光性樹脂層１５Ａは、第一の感光性樹脂層１４Ａを硬化させずに選択的に流路を形成できる感光感度、感光波長等を持つ材料を用いることが好ましい。第二の感光性樹脂の軟化点を低くすることで、接合の際に、第一の感光性樹脂層１４Ａを維持し、基板１との密着性等を維持することが可能となる。 Next, as shown in FIG. 2B, a second photosensitive resin layer 15A is formed by spin coating, slit coating, or the like. The thickness of the second photosensitive resin layer 15A is preferably 5 μm to 200 μm. The second photosensitive resin used for the second photosensitive resin layer 15A is preferably a negative photosensitive resin, and examples thereof include an epoxy resin, an acrylic resin, a urethane resin, a polyimide resin, and a polyamide resin. One or a combination of two or more of these can be used. In contrast to the first photosensitive resin used for the first photosensitive resin layer 14A, a photosensitive resin having a low softening point is used for the second photosensitive resin. In order to maintain the first photosensitive resin layer 14A, soften the second photosensitive resin layer 15A, and improve the adhesion during the heating at the time of bonding, The softening point of the second photosensitive resin is preferably 10 ° C. or more apart. The first photosensitive resin preferably has a softening point of 40 ° C to 90 ° C, and the second photosensitive resin layer preferably has a softening point of 30 ° C to 80 ° C. When forming the flow path, the second photosensitive resin layer 15A is made of a material having photosensitivity, photosensitive wavelength, or the like that can selectively form the flow path without curing the first photosensitive resin layer 14A. Is preferred. By lowering the softening point of the second photosensitive resin, it is possible to maintain the first photosensitive resin layer 14 </ b> A at the time of bonding and maintain the adhesion to the substrate 1.

それぞれの層を形成する感光性組成物には、上記の感光性樹脂以外に光重合開始剤等を含むことができる。本明細書において、光重合開始剤は、重合反応を促進する材料のみならず、架橋反応を促進する材料も含む概念である。光重合開始剤としては、例えば、オニウム塩やジアゾニウム塩などの光酸発生剤、またはチタノセン化合物やｐ−ニトロベンジル芳香族スルホネート等のラジカル重合開始剤等を挙げることができる。第一および第二の感光性樹脂層の感光感度、感光波長等の調整は、それぞれの層を形成する感光性組成物中の成分、例えば、感光波長の異なる感光性樹脂の選択、光重合開始剤の種類や添加量により適宜実施できる。これにより、第一および第二の感光性樹脂層は、樹脂の軟化点以外にも、感光感度および感光波長の少なくとも一方が異なる感光性を有する材料で形成されることとなる。第一の感光性樹脂層１４Ａは焦点深度の浅い短波長の露光光（例えば、ｉ線：３６５ｎｍ）で硬化できる材料を、第二の感光性樹脂層１５Ａは焦点深度の深い長波長の露光光（例えば、ｇｈ線：４０５、４３６ｎｍ）で硬化できる材料を選択することが好ましい。また、それぞれの露光量は、例えば、第一の感光性樹脂層１４Ａには５００Ｊ／ｍ^２〜２０００Ｊ／ｍ^２、第二の感光性樹脂層１５Ａには５０００Ｊ／ｍ^２〜１００００Ｊ／ｍ^２とすることができる。したがって、第一の感光性樹脂層１４Ａの感光感度は、第二の感光性樹脂層１５Ａの感光感度よりも高いことが好ましい。 The photosensitive composition forming each layer can contain a photopolymerization initiator and the like in addition to the photosensitive resin. In the present specification, the photopolymerization initiator is a concept including not only a material that promotes a polymerization reaction but also a material that promotes a crosslinking reaction. Examples of the photopolymerization initiator include photoacid generators such as onium salts and diazonium salts, and radical polymerization initiators such as titanocene compounds and p-nitrobenzyl aromatic sulfonates. Adjustment of the photosensitive sensitivity, photosensitive wavelength, etc. of the first and second photosensitive resin layers is made by selecting components in the photosensitive composition forming the respective layers, for example, photosensitive resins having different photosensitive wavelengths, and starting photopolymerization. It can be carried out as appropriate depending on the type of agent and the amount added. As a result, the first and second photosensitive resin layers are formed of materials having photosensitivities that differ in at least one of photosensitivity and photosensitive wavelength, in addition to the softening point of the resin. The first photosensitive resin layer 14A is made of a material that can be cured with short wavelength exposure light (for example, i-line: 365 nm) with a shallow depth of focus, and the second photosensitive resin layer 15A is a long wavelength exposure light with a deep depth of focus. It is preferable to select a material that can be cured by (for example, gh line: 405, 436 nm). Further, each of the exposure amount, for example, the first photosensitive resin layer ^{^{14A 500J / m 2 ~2000J / m}} 2, the second photosensitive resin layer 15A 5000 J ^/ m 2 and ~10000J / ^{m 2} can do. Therefore, the photosensitive sensitivity of the first photosensitive resin layer 14A is preferably higher than the photosensitive sensitivity of the second photosensitive resin layer 15A.

次に図２（ｃ）に示すように、形成した第一の感光性樹脂層１４Ａ、第二の感光性樹脂層１５Ａ等の積層膜から、ベースとなるフィルム２１を除去し積層構造体２２を形成する。フィルム２１と積層構造体２２を機械的に剥がすことも可能である。また、フィルム２１にＰＶＡ等を用いることで、積層構造体２２を溶解させない純水でフィルム２１を溶解除去することも可能である。この場合は機械的に剥がす場合に比べて容易に歩留まりが向上する効果がある。 Next, as shown in FIG. 2C, the base film 21 is removed from the formed laminated film such as the first photosensitive resin layer 14A and the second photosensitive resin layer 15A, and the laminated structure 22 is obtained. Form. It is also possible to mechanically peel off the film 21 and the laminated structure 22. Further, by using PVA or the like for the film 21, the film 21 can be dissolved and removed with pure water that does not dissolve the laminated structure 22. In this case, there is an effect that the yield is easily improved as compared with the case of mechanical peeling.

積層構造体２２の製造方法は図２に示したものに限定されず、フィルム２１を除去することなく、吐出口形成部材の材料の一部として用いることもできる。また、積層構造体２２は、溶融押出成型法、共押出法、カレンダー法、ラミネート法、延伸等の公知のフィルム形成方法を組み合わせて製造しても良い。この場合は、ベースとなるフィルム２１を用いずに第一および第二の感光性樹脂の積層構造体を形成することが可能であり、ベースとなるフィルム２１を除去する工程が削減され更に歩留まりが向上する効果が得られる。さらに、積層構造体２２には第二の感光性樹脂層１５Ａの基板１との密着性を良化する密着層が部分的に形成されてもよく、また、第一の感光性樹脂層１４Ａの上に撥水層が形成されていても良い。積層構造体２２の一部に無機材料を用いることもできる。 The manufacturing method of the laminated structure 22 is not limited to that shown in FIG. 2, and can be used as a part of the material of the discharge port forming member without removing the film 21. The laminated structure 22 may be manufactured by combining known film forming methods such as a melt extrusion molding method, a coextrusion method, a calendar method, a laminating method, and stretching. In this case, the laminated structure of the first and second photosensitive resins can be formed without using the base film 21, and the process of removing the base film 21 is reduced, and the yield is further increased. An improving effect is obtained. Furthermore, the laminated structure 22 may be partially formed with an adhesion layer for improving the adhesion of the second photosensitive resin layer 15A to the substrate 1, and the first photosensitive resin layer 14A. A water repellent layer may be formed thereon. An inorganic material can also be used for a part of the laminated structure 22.

次に図３（ａ）に示される基板１の第１面上には、液体吐出エネルギー発生素子（不図示）が複数配置され、第１面から反対の第２面に貫通する液体供給路１１が形成されている。なお、基板１は、基材としてシリコンウエハを用いて、１枚のシリコンウエハ上に多数の液体吐出ヘッドを同時に形成する。予め基板１を貫通する液体供給路１１を形成するため、オーバーエッチングが可能となり、ウエハ面内での開口不良等を抑制することができる。 Next, a plurality of liquid ejection energy generating elements (not shown) are arranged on the first surface of the substrate 1 shown in FIG. 3A, and the liquid supply path 11 penetrates from the first surface to the opposite second surface. Is formed. The substrate 1 uses a silicon wafer as a base material, and simultaneously forms a large number of liquid ejection heads on a single silicon wafer. Since the liquid supply path 11 penetrating the substrate 1 is formed in advance, over-etching is possible, and defective openings in the wafer surface can be suppressed.

次に図３（ｂ）に示すように、積層構造体２２を基板１の第１面上に第二の感光性樹脂層１５が接触するようにローラー方式のラミネート装置により接合していく。この時、操作方向３２に向かってローラー３１を第一の感光性樹脂層１４Ａ上に押し当てていく。接合の条件としてはローラー３１と接する第一の感光性樹脂層１４Ａの軟化点より低い温度を上限とし、９０℃未満が好ましく、下限として、第二の感光性樹脂層１５Ａの軟化点以上の３０℃以上の温度が好ましい。特に、３０℃〜７０℃の温度範囲が好ましい。また、第一の感光性樹脂層１４Ａを第二の感光性樹脂層１５Ａよりも厚く形成する際、貼り合わせた後、所望の厚さまで機械的な研磨（ＣＭＰ）やドライエッチング等により薄くすることもできる。また、基板温度を第二の感光性樹脂層１５Ａの軟化点より高く設定し、ローラー温度を、第二の感光性樹脂層１５Ａの軟化点よりも低くすることで、基板外の余分な領域に膜が形成されることを防ぐ効果がある。 Next, as shown in FIG. 3B, the laminated structure 22 is joined by a roller type laminating apparatus so that the second photosensitive resin layer 15 contacts the first surface of the substrate 1. At this time, the roller 31 is pressed against the first photosensitive resin layer 14 </ b> A in the operation direction 32. As a bonding condition, a temperature lower than the softening point of the first photosensitive resin layer 14A in contact with the roller 31 is set as an upper limit, preferably less than 90 ° C., and a lower limit is 30 which is equal to or higher than the softening point of the second photosensitive resin layer 15A. A temperature of ° C or higher is preferred. In particular, a temperature range of 30 ° C to 70 ° C is preferable. Further, when the first photosensitive resin layer 14A is formed thicker than the second photosensitive resin layer 15A, after bonding, the first photosensitive resin layer 14A is thinned to a desired thickness by mechanical polishing (CMP), dry etching, or the like. You can also. In addition, by setting the substrate temperature higher than the softening point of the second photosensitive resin layer 15A and lowering the roller temperature lower than the softening point of the second photosensitive resin layer 15A, an extra area outside the substrate is formed. There is an effect of preventing the formation of a film.

次に図３（ｃ）に示すように、流路１２のパターンを有する第一のマスク３３を用いて、第一の露光光３４にて露光する第１露光工程を実施する。第１露光工程では、第一の感光性樹脂層１４Ａを硬化させずに、第二の感光性樹脂層１５Ａを選択的に露光して第二の層１５を形成する。なお、第１露光工程では、第一の感光性樹脂層１４Ａが硬化しても、その部分は、液体流路１２の壁部を構成する第二の層１５と第一の層１４との接合部となるため、特に問題はない。 Next, as shown in FIG. 3C, a first exposure process is performed in which exposure is performed with the first exposure light 34 using the first mask 33 having the pattern of the flow path 12. In the first exposure step, the second photosensitive resin layer 15A is selectively exposed to form the second layer 15 without curing the first photosensitive resin layer 14A. In the first exposure step, even if the first photosensitive resin layer 14 </ b> A is cured, the portion is a joint between the second layer 15 and the first layer 14 constituting the wall portion of the liquid flow path 12. Because it becomes a part, there is no particular problem.

次に図３（ｄ）に示すように、吐出口１３のパターンを有する第二のマスク３５を用いて、第二の露光光３６にて露光する第２露光工程を実施する。この時、未硬化の第二の感光性樹脂層１５Ａを硬化させず、第一の感光性樹脂層１４Ａを選択的に露光して第一の層１４を形成する。このようにして、第二の感光性樹脂層１５Ａを第二の層１５に、第一の感光性樹脂層１４Ａを第一の層１４に、それぞれ形成する。 Next, as shown in FIG. 3D, a second exposure process is performed in which exposure is performed with the second exposure light 36 using the second mask 35 having the pattern of the ejection ports 13. At this time, the uncured second photosensitive resin layer 15A is not cured, and the first photosensitive resin layer 14A is selectively exposed to form the first layer 14. In this manner, the second photosensitive resin layer 15A is formed on the second layer 15, and the first photosensitive resin layer 14A is formed on the first layer 14, respectively.

次に図３（ｅ）に示すように、各層の未硬化領域を現像することで流路１２と吐出口１３が形成され、液体吐出ヘッド構造が形成される。なお、各層を一括で現像することが好ましい。さらに、現像後に、第一の層１４および第二の層１５をさらに硬化させるための熱処理を施しても良い。 Next, as shown in FIG. 3E, the uncured region of each layer is developed to form the flow path 12 and the discharge port 13, thereby forming the liquid discharge head structure. It is preferable to develop each layer at once. Further, after the development, a heat treatment for further curing the first layer 14 and the second layer 15 may be performed.

以上の工程を経た後、ウエハをダイシングソー等によって、切断分離して個々の液体吐出ヘッドにチップ化する。液体吐出エネルギー発生素子２を駆動させる電気配線を行った後、液体供給用のチップタンク部材を接合することで、液体吐出ヘッドが完成する。 After passing through the above steps, the wafer is cut and separated by a dicing saw or the like to form chips in individual liquid discharge heads. After the electrical wiring for driving the liquid discharge energy generating element 2 is performed, the liquid supply head is completed by joining the chip tank member for supplying liquid.

積層構造体は、第一の感光性樹脂層と、前記第一の感光性樹脂層よりも軟化点の低い最外層を含む第二の感光性樹脂層を備える２層以上の構成である。図４に示すように、積層構造体は、第一の感光性樹脂層１４Ａ側に軟化点の高い第二の感光性樹脂層（第１層）１６と、基板１と接触させる接触層となる軟化点の低い第二の感光性樹脂層（第２層）１７との複数の層を含む第二の感光性樹脂層１５Ａを有しても良い。この場合、第２層１７が最外層となる。第１層１６は、第一の感光性樹脂層１４Ａの軟化点以上の軟化点を有しても良い。第一の感光性樹脂層１４Ａと、第１層１６で、剛性を維持することが可能となり、同時に第２層１７と、基板１との密着等も維持することが出来る。この場合、剛性を高めることで歩留りが向上する効果が得られる。また、吐出口１３を規定する第一の層１４を薄く形成することが容易となり、液体吐出特性が向上する効果が得られる。また、第１層１６と第２層１７は、１回の露光で第二の層１５に硬化させても良く、複数回の露光で硬化させても良い。１回の露光で第二の層１５に硬化させる場合、第１層１６と第２層１７は同等の感光感度を有するか、同等の感光波長を有する材料で構成されることが好ましい。例えば同種の感光性樹脂で形成した２つの層は、同等の感光感度を有する。また、同等の感光波長を有する。また、複数回の露光では、異なる液体流路パターン、例えば、第２層１７に第一の液体流路パターンを形成し、第１層１６に第一の液体流路パターンより幅を狭くした第二の液体流路パターンを形成しても良い。また、複数回の露光では、それぞれ異なる波長、露光量にて露光することが可能であり、それに適した材料を適宜選択して用いれば良い。したがって、リソグラフィー工程を２回以上の異なるパターンと露光条件で行うことができるが、現像はこの場合も一括して行うことが好ましい。 The laminated structure has a configuration of two or more layers including a first photosensitive resin layer and a second photosensitive resin layer including an outermost layer having a softening point lower than that of the first photosensitive resin layer. As shown in FIG. 4, the laminated structure becomes a second photosensitive resin layer (first layer) 16 having a high softening point on the first photosensitive resin layer 14 </ b> A side and a contact layer in contact with the substrate 1. You may have the 2nd photosensitive resin layer 15A containing several layers with the 2nd photosensitive resin layer (2nd layer) 17 with a low softening point. In this case, the second layer 17 is the outermost layer. The first layer 16 may have a softening point equal to or higher than the softening point of the first photosensitive resin layer 14A. The first photosensitive resin layer 14A and the first layer 16 can maintain rigidity, and at the same time, the adhesion between the second layer 17 and the substrate 1 can be maintained. In this case, the yield can be improved by increasing the rigidity. Further, it is easy to form the first layer 14 that defines the discharge port 13 thin, and the effect of improving the liquid discharge characteristics can be obtained. The first layer 16 and the second layer 17 may be cured to the second layer 15 by one exposure, or may be cured by a plurality of exposures. When the second layer 15 is cured by one exposure, it is preferable that the first layer 16 and the second layer 17 have the same photosensitive sensitivity or be made of a material having an equivalent photosensitive wavelength. For example, two layers formed of the same type of photosensitive resin have equivalent photosensitivity. Moreover, it has an equivalent photosensitive wavelength. Further, in the multiple exposures, different liquid flow path patterns, for example, the first liquid flow path pattern is formed in the second layer 17 and the first layer 16 is narrower than the first liquid flow path pattern. Two liquid flow path patterns may be formed. Further, in multiple times of exposure, exposure can be performed with different wavelengths and exposure amounts, and a suitable material may be selected and used as appropriate. Therefore, the lithography process can be performed two or more times with different patterns and exposure conditions, but it is preferable that the development be performed in this case as well.

上述のように、本発明では、（１）基板を準備する工程と、（２）積層構造体を形成する工程と、（３）積層構造体を接合する工程と、（４）積層構造体を露光し、第二層と第一の層とを形成する工程と、を有する。この（１）から（４）の工程は、この順番で行うことが好ましい。 As described above, in the present invention, (1) a step of preparing a substrate, (2) a step of forming a laminated structure, (3) a step of joining the laminated structure, and (4) a laminated structure Exposing to form a second layer and a first layer. The steps (1) to (4) are preferably performed in this order.

実施例１
図２、図３を用いて本実施例に係る液体吐出ヘッドの製造方法について説明する。図２は本発明の積層構造体の製造方法の一例を説明するための図であり、図３は本発明の液体吐出ヘッド用の製造方法の一例を説明するための図であり、図１のＡ−Ａ’における断面を示す図である。 Example 1
A method of manufacturing the liquid discharge head according to the present embodiment will be described with reference to FIGS. 2 is a diagram for explaining an example of the manufacturing method of the laminated structure of the present invention, and FIG. 3 is a diagram for explaining an example of the manufacturing method for the liquid discharge head of the present invention. It is a figure which shows the cross section in AA '.

まず、図２（ａ）に示すように、ベースとなるフィルム２１上に第一の感光性樹脂層１４Ａをスピンコート塗布により形成した。第一の感光性樹脂層１４Ａの厚みは２０μｍにて形成した。第一の感光性樹脂層１４Ａに用いる第一の感光性樹脂としては、感光波長（３６５ｎｍ）のクレゾール型エポキシ樹脂を使用した。また、軟化点は７０℃であった。 First, as shown in FIG. 2A, a first photosensitive resin layer 14A was formed on a base film 21 by spin coating. The thickness of the first photosensitive resin layer 14A was 20 μm. As the first photosensitive resin used for the first photosensitive resin layer 14A, a cresol type epoxy resin having a photosensitive wavelength (365 nm) was used. The softening point was 70 ° C.

次に、図２（ｂ）に示すように、第二の感光性樹脂層１５をスピンコート塗布により形成した。第二の感光性樹脂層１５の厚みは４０μｍで形成した。第二の感光性樹脂としては、感光波長（４０５、４３６ｎｍ）で、第一の感光性樹脂よりも軟化点の低いビスフェノールＡ型エポキシ樹脂（軟化点：４０℃）を使用した。 Next, as shown in FIG. 2B, a second photosensitive resin layer 15 was formed by spin coating. The thickness of the second photosensitive resin layer 15 was 40 μm. As the second photosensitive resin, a bisphenol A type epoxy resin (softening point: 40 ° C.) having a photosensitive wavelength (405, 436 nm) and a softening point lower than that of the first photosensitive resin was used.

次に図２（ｃ）に示すように、形成した第一の感光性樹脂層１４Ａ、第二の感光性樹脂層１５Ａの積層膜から、ベースとなるフィルム２１を剥離テープにより剥離し、積層構造体２２を形成した。 Next, as shown in FIG. 2C, the base film 21 is peeled off from the formed laminated film of the first photosensitive resin layer 14A and the second photosensitive resin layer 15A with a release tape, and a laminated structure is formed. A body 22 was formed.

次に図３（ａ）に示される基板１上には、液体吐出エネルギー発生素子（不図示）が複数配置され、液体供給路１１が形成されている基板を準備した。 Next, a substrate on which a plurality of liquid discharge energy generating elements (not shown) are arranged and the liquid supply path 11 is formed on the substrate 1 shown in FIG.

次に図３（ｂ）に示すように、積層構造体２２を基板１上に流路を形成する感光性樹脂からなる層１５が接するように真空接合装置により５０℃にて貼付けを行った。 Next, as shown in FIG. 3B, the laminated structure 22 was attached at 50 ° C. with a vacuum bonding apparatus so that the layer 15 made of a photosensitive resin forming a flow path was in contact with the substrate 1.

次に図３（ｃ）に示すように、第一の感光性樹脂層１４Ａを硬化させずに選択的に第二の感光性樹脂層１５Ａを硬化できる第一の露光光３４として、波長（４０５、４３６ｎｍ）の光を６０００Ｊ／ｍ^２にて照射し、第二の層１５を形成した。 Next, as shown in FIG. 3C, as the first exposure light 34 that can selectively cure the second photosensitive resin layer 15A without curing the first photosensitive resin layer 14A, the wavelength (405) is used. , 436 J / m ² , and the second layer 15 was formed.

次に図３（ｄ）に示すように、未露光の第二の感光性樹脂層１５Ａを硬化させずに選択的に吐出口１３となる部分を除く第一の感光性樹脂層１４Ａを硬化できる第二の露光光３６として、波長（３６５ｎｍ）の光を１０００Ｊ／ｍ^２にて照射し、第一の層１４を形成した。 Next, as shown in FIG. 3D, the first photosensitive resin layer 14A excluding the portion that becomes the discharge port 13 can be selectively cured without curing the unexposed second photosensitive resin layer 15A. As the second exposure light 36, light having a wavelength (365 nm) was irradiated at 1000 J / m ² to form the first layer 14.

次に図３（ｅ）に示すように、各層を枚葉式現像装置にて一括現像することで流路１２と吐出口１３を形成した。 Next, as shown in FIG. 3E, the channels 12 and the discharge ports 13 were formed by collectively developing each layer with a single-wafer developing device.

その他、チップ化、配線等の所要の工程を経て、液体吐出ヘッドが完成する。この液体吐出ヘッドを観察し、図５に示すようなベースフィルム剥離時に発生していたノズルクラックなどの不良がないことを確認した。 In addition, the liquid discharge head is completed through necessary steps such as chip formation and wiring. This liquid discharge head was observed and it was confirmed that there were no defects such as nozzle cracks that occurred when the base film was peeled off as shown in FIG.

比較として、積層構造体２２を軟化点が同じで感光波長のみが異なる２種類の感光性樹脂で形成すると、基板１上に貼付けの際に密着不足により、歩留まりが低下した。 As a comparison, when the laminated structure 22 was formed of two types of photosensitive resins having the same softening point and different photosensitive wavelengths, the yield was lowered due to insufficient adhesion when pasted on the substrate 1.

更に、積層構造体２２の軟化点を逆にし、軟化点の低い感光性樹脂で第一の感光性樹脂層を形成し、軟化点の高い感光性樹脂で第二の感光性樹脂層の形成を行うと、基板１上に積層構造体を貼りつける際に密着不足により、歩留まりが低下した。また、接合時の温度を上げると装置内のローラー等に貼付き不良となり歩留まりが低下した。 Further, the softening point of the laminated structure 22 is reversed, the first photosensitive resin layer is formed with a photosensitive resin having a low softening point, and the second photosensitive resin layer is formed with a photosensitive resin having a high softening point. As a result, the yield decreased due to insufficient adhesion when the laminated structure was bonded onto the substrate 1. Moreover, when the temperature at the time of joining was raised, it stuck to the roller etc. in an apparatus, etc., and the yield fell.

１：基板
２：液体吐出エネルギー発生素子
３：吐出口形成部材
１１：液体供給路
１２：液体流路
１３：液体吐出口
１４：第一の層
１４Ａ：第一の感光性樹脂層
１５：第二の層
１５Ａ：第二の感光性樹脂層
１６：軟化点の高い第二の感光性樹脂層
１７：軟化点の低い第二の感光性樹脂層
２１：ベースフィルム
２２：積層構造体
３１：ローラー
３２：ローラー操作方向
３３：第一のマスク
３４：第一の露光光
３５：第二のマスク
３６：第二の露光光 1: substrate 2: liquid discharge energy generating element 3: discharge port forming member 11: liquid supply path 12: liquid flow path 13: liquid discharge port 14: first layer 14A: first photosensitive resin layer 15: second Layer 15A: second photosensitive resin layer 16: second photosensitive resin layer 17 having a high softening point: second photosensitive resin layer 21 having a low softening point 21: base film 22: laminated structure 31: roller 32 : Roller operation direction 33: first mask 34: first exposure light 35: second mask 36: second exposure light

Claims

A method for manufacturing a liquid ejection head, comprising:
(1) preparing a substrate having a liquid discharge energy generating element on the first surface and having a liquid supply path penetrating from the first surface to the opposite second surface;
(2) A step of forming a laminated structure of two or more layers including a first photosensitive resin layer and a second photosensitive resin layer including an outermost layer having a softening point lower than that of the first photosensitive resin layer. When,
(3) bonding the laminated structure on the first surface of the substrate by bringing the outermost layer of the second photosensitive resin layer of the laminated structure into contact with each other;
(4) Exposing the laminated structure, the second layer defining a liquid flow path in the second photosensitive resin layer, and the first layer defining an ejection port in the first photosensitive resin layer Forming each of the above,
A method for manufacturing a liquid discharge head, comprising:

The method of manufacturing a liquid ejection head according to claim 1, wherein the steps (1) to (4) are performed in this order.

3. The liquid according to claim 1, wherein the first and second photosensitive resin layers include at least one negative photosensitive resin of an epoxy resin, an acrylic resin, a urethane resin, a polyimide resin, and a polyamide resin. Manufacturing method of the discharge head.

4. The liquid ejection head according to claim 1, wherein the first and second photosensitive resin layers are formed of a material having photosensitivity different in at least one of photosensitivity and photosensitivity wavelength. 5. Method.

The method of manufacturing a liquid ejection head according to claim 4, wherein after the step (4) is performed twice or more with different patterns and exposure conditions, development is performed in a lump.

The method of manufacturing a liquid ejection head according to claim 4, wherein the photosensitive sensitivity of the first photosensitive resin layer is higher than the photosensitive sensitivity of the second photosensitive resin layer.

The method of manufacturing a liquid discharge head according to claim 4, wherein a photosensitive wavelength of the first photosensitive resin layer is shorter than a photosensitive wavelength of the second photosensitive resin layer.

In the step (3), the laminated structure is bonded to the substrate at a temperature lower than the softening point of the first photosensitive resin layer and higher than the softening point of the outermost layer of the second photosensitive resin layer. The method for manufacturing a liquid discharge head according to claim 1.

A roller-type laminating apparatus is used for joining the laminated structure and the substrate, the temperature of the substrate is equal to or higher than the softening point of the outermost layer of the second photosensitive resin layer, and the roller temperature is the second photosensitive resin. The method of manufacturing a liquid discharge head according to claim 8, wherein the liquid discharge head is lower than a softening point of the outermost layer of the layer.

The method of manufacturing a liquid ejection head according to claim 1, wherein a thickness of the first photosensitive resin layer is equal to or less than a thickness of the second photosensitive resin layer.

The liquid discharge head according to claim 10, further comprising a step of polishing a part of the first photosensitive resin layer after bonding the laminated structure and before exposing the first photosensitive resin layer. Manufacturing method.

The liquid according to claim 11, wherein the thickness of the first photosensitive resin layer is formed to be equal to or greater than the thickness of the second photosensitive resin layer and is made thinner than the thickness of the second photosensitive resin layer by the polishing. Manufacturing method of the discharge head.

The laminate structure is formed by forming a laminate including the first and second photosensitive resin layers on a base film and then peeling the base film before bonding to the substrate. 2. A method for manufacturing a liquid discharge head according to 1.

The second photosensitive resin layer includes a first layer and a second layer that has a lower softening point than the first layer and the first photosensitive resin layer and serves as a layer in contact with the substrate. The method for manufacturing a liquid discharge head according to claim 1.

The first layer and the second layer of the second photosensitive resin layer have equivalent photosensitivity, and the softening point of the first layer of the second photosensitive resin layer is the first photosensitive resin layer. The method of manufacturing a liquid discharge head according to claim 14, wherein the liquid discharge head is equal to or higher than the softening point.

The first layer and the second layer of the second photosensitive resin layer have the same photosensitive wavelength, and the softening point of the first layer of the second photosensitive resin layer is the first photosensitive resin layer. The method of manufacturing a liquid discharge head according to claim 14, wherein the liquid discharge head is equal to or higher than the softening point.