JP2004255273A - Solution spray manufacturing apparatus, manufactured pattern wiring board and device substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high quality high precision pattern wiring board and a device substrate. <P>SOLUTION: A liquid drop spray apparatus 1 sprays a plurality of the liquid drops of a fine particle-containing solution to a substrate 14 by a spray head 11 and volatilizing a volatile component in the liquid drops to form a pattern wiring or a device. The surface roughness of the pattern forming surface of the substrate is larger than the diameter of the fine particle. When the size of the fine particle is expressed by Dp and the diameter of a discharge port is expressed by Do, a relation of 0.0001≤Dp/Do≤0.01 is satisfied. The solution is sprayed from the spray head by the growing force of the bubbles of film boiling produced in a moment in the solution. The shape of the liquid drops in the flying of the liquid drop is a narrow long shape extending in the flying direction and the length is controlled to ≥5 times of the diameter, and the relative moving speed of the spray head to the substrate is controlled to ≤1/3 times of the spray speed of the solution. The pattern is formed from the quantity of the liquid as much as the dots of the solution in the arrangement of the dots in a line and is formed by implanting in the density of ≤Ld/2 when the diameter of the dot in the individual formation of the dot is expressed by Ld. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００９２】
【表２】

【００９３】
【表３】

【００９４】
【表４】

【００９５】
以上の結果より、吐出口径がΦ５μｍ〜Φ２０μｍの噴射ヘッドを用いた場合、Ａｇ微粒子径Ｄｐと吐出口径Ｄｏとは、Ｄｐ／Ｄｏ≦０．０１の関係を満足するようにすれば目詰まりのない安定した液滴噴射が得られることがわかる。なお、Ｄｐ／Ｄｏの下限値であるが、このように大変微細な微粒子を安定して、溶液中に分散することを考えると、Ａｇ微粒子径Ｄｐが０．０００３μｍ以下は困難である。また、吐出口径がΦ２０μｍ以下の噴射ヘッド全てに安定して液滴噴射させられるようにするには、余裕をみてＤｐ／Ｄｏの下限値を０．０００１にすればよい。すなわち、Ａｇ微粒子径Ｄｐと吐出口径Ｄｏとは、０．０００１≦Ｄｐ／Ｄｏ≦０．０１の関係を満足するようにすれば、吐出口径がΦ２０μｍ以下の噴射ヘッドを使用した液滴噴射によるパターン形成、あるいはデバイス形成を行うことができる安定した分散液を製造でき、吐出口（ノズル）の目詰まりも生じないようにすることができることがわかる。
【００９６】
なおこの実験では、丸形状の吐出口（ノズル）を使用したが、他の形状の場合は、その面積比較をすればよく、たとえば１８μｍ×１８μｍの矩形吐出口の場合は、本発明の丸形状のΦ２０μｍノズルとほぼ同等である。言い換えるならば、本発明は面積がほぼ３００μｍ^２以下のノズルを使用した噴射ヘッド、またその下限値はほぼ２０μｍ^２のノズル（吐出口径がΦ５μｍ）で、このような溶液を噴射してパターン形成、あるいはデバイス形成を行う場合に適用されるものである。
【００９７】
また実験はピエゾ素子を液滴吐出の原動力とした噴射ヘッドを使用したが、この微粒子含有溶液を微小吐出口から噴射するという原理そのものに起因する目詰まりの課題は、後述する溶液中に瞬時に発生させた膜沸騰気泡の成長作用力を利用して微粒子含有溶液を微小吐出口から噴射するという原理にもとづく噴射ヘッドにも共通の課題であり、膜沸騰気泡利用の噴射ヘッドにも上記結果はそのまま適用することができる。
【００９８】
またサーマルヘッド等を用いて膜沸騰気泡を発生させる方式はその構造上、発熱体部や、吐出口部の高密度、高集積配列が可能で、６００ｄｐｉ〜１２００ｄｐｉあるいはそれ以上の配列密度で、かつ吐出口（ノズル）数も５００〜１００００個というものが容易に実現でき、生産効率の高い製造装置に適している。
【００９９】
次に本発明の他の特徴について説明する。前述のように本発明は微粒子含有溶液が微小な吐出口から目詰まりを起こすことなく安定した液滴噴射するようにしたものであるが、ここでは溶液噴射後に基板上に溶液が付着し、良好なパターン、あるいはデバイスを形成するにはどのようにしたらよいのかを検討した結果を示す。
【０１００】
前述のように本発明では、吐出ヘッドユニット１１は基板１４に対して一定の距離を保ちながらパターン、あるいは機能デバイス群の形成面に対して平行にＸ、Ｙ方向の相対移動を行いつつ、パターン、あるいは機能デバイス群を形成する。すなわち、基板１４に対して、吐出ヘッドユニット１１が基板面に対して平行移動する、もしくは吐出ヘッドユニット１１に対して基板１４が平行移動する。
【０１０１】
その際、パターン、あるいは機能デバイス群を形成するための微粒子含有溶液の噴射を行う毎に相対移動を止めて噴射を行うと高精度なパターン、あるいは機能デバイス群を形成することが可能である。しかし生産性が著しく低下するので、その相対移動を止めることなく、順次溶液の噴射を行うようにしている。その場合、その相対移動速度（例えば図２のキャリッジ１２のＸ方向移動速度）は、単に生産性向上だけで決定されるべきではなく、高精度なパターン、あるいは機能デバイス群を形成するという観点からも検討されなければならない。
【０１０２】
図１１は、本発明が好適に使用される膜沸騰気泡の成長作用力を利用して微粒子含有溶液を微小吐出口から噴射させた場合の噴射、飛翔時の溶液の形状を示したものである。図１２、図１３は、ピエゾ素子を液滴吐出の原動力とし、機械的作用力で噴射させた場合の噴射、飛翔時の溶液の形状を示したものである。
【０１０３】
図１１と図１２および図１３の違いは、図１１の場合が、溶液の一部を瞬時（数μｓの間）に３００〜４００℃に加熱させ、膜沸騰気泡を発生させ、その気泡の瞬時（数μｓの間）の成長、圧力上昇（作用力）を利用して溶液を噴射するために、ピエゾ素子を液滴吐出の原動力とし、機械的作用力で噴射させた場合よりも噴射圧力が高く、噴射速度も速いという点である。その結果、図１１に示すように、飛翔時に、溶液の飛翔形状が飛翔方向に細長柱状に伸び、後方に複数の微小な滴（サテライト微小滴８１）を伴って高速で飛翔するという特徴を持っている。たとえば、溶液飛翔時の形状は、通常安定した膜沸騰気泡を発生させて飛翔させた場合、飛翔方向に伸びた細長柱状の長さｌは、その直径ｄの５倍以上の長さとなり、またその速度は、ほぼ５ｍ／ｓ〜２０ｍ／ｓとなって飛翔する。
【０１０４】
その結果、噴射が安定し噴射された溶液の基板上への着弾精度が高いという利点があるが、一方で、噴射ヘッドと基板の相対移動速度を適切に選ばないと、飛翔方向に細長柱状に伸びた後方部の溶液や、後方に連なった複数の微小な滴（サテライト微小滴８１）が、良好な丸いドット形成を妨げることもなる。
【０１０５】
本発明ではこの点に関して鋭意検討した結果、このような微粒子含有溶液の噴射を行う場合、その噴射速度と前記相対移動速度との間の関係を最適化することが必要であることに気がついた。
【０１０６】
ところでこのように吐出ヘッドユニット１１を基板１４に対して一定の距離を保ちながらＸ、Ｙ方向の相対移動を行いつつ、微粒子含有溶液の噴射を行い、パターン、あるいは機能デバイス群を形成する場合には、溶液は前記相対速度と噴射速度の合成ベクトルの速度で基板１４上に付着、形成される。そしてその位置精度については、基板１４と吐出ヘッドユニット１１の溶液噴射口面の距離と、前記合成ベクトルの速度を考慮し、噴射のタイミングを適宜選ぶことにより、その狙いの位置に溶液を付着させることができる。
【０１０７】
しかしながら、たとえ狙いの位置に付着させることができたとしても、もし、前記相対速度が速すぎる場合には、その相対速度に引きずられて付着溶液が基板１４上で流れ、良好な丸いドット形状とならず、良好なパターン、あるいは機能デバイス群を形成できなくなる。また、後方に連なった複数の微小な滴（サテライト微小滴８１）が、本来付着すべき位置から外れた位置に、ランダムに散らばった状態で付着し、良好な丸いドット形成の妨げ、機能デバイス性能の低下を引き起こす場合がある。本発明はこの点について検討したものである。
【０１０８】
以下に検討結果の１例を示す。この例は、図２のような装置を用い、キャリッジ１２のＸ方向移動速度、ならびに吐出ヘッドユニット１１の噴射速度を変えて、基板１４上で良好な溶液付着ができ、良好なパターン形成ができるかどうか調べたものである。
【０１０９】
図１４にテストに使用したパターンの例を示す。ここでは、Ａｇ微粒子含有溶液を噴射させ、２列の近接した素子電極間（ＩＴＯ透明電極８２間）を、前記溶液によるドットパターンをつなぎ合わせた配線パターンを形成し、そのパターンの形成状況を評価したものである。評価は、形成後のパターンを顕微鏡下で観察し、良／不良（○／×）を判断した。図１４（Ａ）は良（○）であり、図１４（Ｂ）のように、個々のドットパターンが良好な丸い形状にならず、長円形になったり、基板上における着弾位置も本来の狙いの位置から外れたりして、隣のドットパターンと接触したりするようなものは不良（×）である。さらに、サテライト滴に起因する微小な滴が散在しているようなものも不良（×）とした。
【０１１０】
このような形状の評価とあわせて、上下のＩＴＯ透明電極間の抵抗値を測定し、ドット位置精度不良による断線あるいは隣（左右）のドットとの接触による抵抗値変動などを評価した（○：狙い通りの抵抗値、×：狙いから外れた抵抗値）。
【０１１１】
実験条件の詳細を以下に示す。使用した基板はＩＴＯ透明電極付きガラス基板であり、前述のＡｇ微粒子含有溶液（ここでは、微粒子径が０．０１μｍのものを使用）を図７に示した噴射ヘッド（ただし、Φ５μｍのノズルを設けたＮｉエレクトロフォーミング形成のマルチノズルプレートを別途設けたもの）と組み合わせて、図１４のようなドットパターン８３を形成した。なお、図１４は簡略化のため、１対のＩＴＯ透明電極８２間を４ドットで埋めるように形成した図を示しているが、実際には、縦方向に１列で、約Φ８μｍのドットを約４μｍピッチで約１０００個打ち込み、上下のＩＴＯ透明電極８２間（電極間距離４ｍｍ）をつないでいる。また隣に中心間距離を１２μｍとして、同様のＩＴＯ透明電極８２およびＩＴＯ透明電極８２間をつなぐ同様のパターンを形成している。
【０１１２】
使用した噴射ヘッドは前述のような噴射ヘッド（図７は、簡略化した４個のノズルを示している）であるが、ノズル（吐出口）数を６４個としている。またその配列密度が４００ｄｐｉのものである。発熱体サイズは１０μｍ×４０μｍであり、その抵抗値は１０２Ωである。ヘッドの駆動電圧は１１Ｖ、パルス幅は２μｓ、駆動周波数は１４ｋＨｚとした。噴射滴の体積はほぼ１ｐｌである。
【０１１３】
このような条件で、ガラス基板上に前述のようなパターン（図１４）を形成し、形成後のパターン評価を行うとともに、それと同じ条件で、別途噴射実験を行い、吐出口から３ｍｍ先の溶液の噴射状況を観察した。これは図１４のテストパターンを基板と吐出口間距離を３ｍｍとして製作したからである。飛翔形態は図１１に示したように、飛翔方向に非常に細長く伸びた柱状（ｌ＝５ｄ〜２０ｄ）であった。また飛翔滴後方に複数の微小な滴（サテライト微小滴８１）を伴ったような状態であった。以下に検討結果を示す。
【０１１４】
【表５】

【０１１５】
以上の結果より、キャリッジのＸ方向移動速度が、噴射速度の１／３を超えると、良好な素子が形成できないことがわかる。なおこの例は、噴射ヘッドをキャリッジ走査した例であるが、図３のように噴射ヘッドを固定し、基板を移動させる場合にも適用される。すなわち、噴射ヘッドと基板の相対移動速度は、噴射される溶液の速度の１／３以下にしなければならないということである。
【０１１６】
次に本発明のさらに他の特徴について説明する。本発明の機能を付与された基板（シートを含む）は、無数の微細微粒子、ナノ微粒子を溶液中に分散させてなる微粒子含有溶液をインクジェットの原理で空中を飛翔させ、基板上に液滴として付与して製作されるものであるが、高精度かつ高品位な機能を付与された基板を製作するためには、基板上にナノ微粒子含有溶液を噴射、付与して、微細なパターン形成を行う際の基板の表面粗さとナノ微粒子の大きさを最適化しておく必要がある。たとえば、基板の表面粗さというのは、その表面の凹凸であるが、図１５のように、この凹凸からはみ出すような大きさの粒子が、基板の表面に付着すると、良好なパターンあるいはデバイスが得られないであろう。
【０１１７】
一方で、図１６のように、微粒子８５が基板表面８６の凹凸以下の大きさの粒子であれば、良好なパターンあるいはデバイスが得られるであろう。本発明ではこの点に鑑み、あらかじめ表面粗さのわかっている基板上に、サイズの異なる微粒子を含有させた溶液によって、パターンを形成し、その形成されたパターンの良否を評価した。
【０１１８】
実験は、パイレックス（Ｒ）ガラスを研摩し、その表面粗さが０．０１ｓ〜０．０２ｓとなるようにし、その研摩された基板上に前述のＡｇ微粒子含有溶液（ここでは、微粒子径が０．０００５μｍ〜０．２μｍのものを使用）を、図７に示したような液滴噴射の原動力を溶液中で瞬時に発生する膜沸騰気泡の成長作用力によるサーマル方式（バブル方式）の液体噴射ヘッドと組み合わせて噴射させ、ドットをつなぎあわせたパターンを形成し、そのパターンの滑らかさを顕微鏡下で観察し、官能評価し、良〜可〜不良（○〜△〜×）を判断した。
【０１１９】
なおここでは、図７のように流路がそのままノズル６５となる形式のものではなく、ノズル６５面に別途ノズル孔を穿孔したノズルプレートを設けた構造とした噴射ヘッドを使用した。またそのノズルは、Ｎｉのエレクトロフォーミングにより形成した丸形状のノズルであり、大きさはΦ５μｍ、開口部分の板厚を１０μｍとしたものである。
【０１２０】
またノズル数は６４個、配列密度を４００ｄｐｉとしたものである。発熱体サイズは１０μｍ×４０μｍであり、その抵抗値は１００Ωである。ヘッドの駆動電圧は１０Ｖであり、パルス幅は２μｓ、駆動周波数は１４ｋＨｚとした。この条件で噴射される１滴の液滴量は約１ｐｌである。
【０１２１】
形成したパターンは図１４のようにパイレックス（Ｒ）ガラス上に、上下に０．４ｍｍの間隔に形成したＩＴＯ透明電極８２間に縦方向に１列で、約Φ８μｍのドットを約４μｍピッチで約１００個打ち込んだものである（図１４は簡略化のため４個のドットの例で示している）。
【０１２２】
なおドット間ピッチ４μｍを得るために、噴射ヘッドと基板を相対運動させ（ここでは、基板固定、噴射ヘッドをキャリッジ走査）、その位置をμオーダーで制御し、また噴射のタイミングをコントロールして、上記のように約４μｍピッチによるドット付着を行った。また隣に中心間距離を１２μｍとして、同様のＩＴＯ透明電極およびＩＴＯ透明電極間をつなぐ同様のパターンを形成している。
【０１２３】
このような条件で、ガラス基板上に前述のようなドットパターン（図１４）を形成し、形成後のパターン評価を行うとともに、それと同じ条件で、別途噴射実験を行い、吐出口から３ｍｍ先の溶液の噴射状況を観察した。これは図１４のテストパターンを基板と吐出口間距離を３ｍｍとして製作したからである。飛翔形態は図１１に示したように、飛翔方向に非常に細長く伸びた柱状（ｌ＝５ｄ〜２０ｄ）であった。また飛翔滴後方に複数の微小な滴（サテライト微小滴８１）を伴ったような状態であった。
【０１２４】
なお前述のようにＡｇ微粒子含有溶液は、微粒子径が０．０００５μｍ〜０．２μｍまで異なるものをそれぞれ準備して使用した（溶液Ｎｏ．は共通である）が、微粒子径が０．０２μｍ以上の場合には、ノズル目詰まりが発生し始めるので、形成したパターンのうち、目詰まりが生じなくて、良好にパターン形成されたもののみを選別して評価を行った。以下に結果を示す。
【０１２５】
【表６】

【０１２６】
以上の結果より、溶液に含有される微粒子は、基板のパターンが形成される面の表面粗さ以下の大きさとすることにより、滑らかで良好かつ高精度なパターンが形成できることがわかる。一方で、微粒子の大きさをそれより大きくすると、パターン形状の滑らかさが損なわれることがわかる。
【０１２７】
言い換えるならば、滑らかな良好なパターン形成するためには、基板のパターンが形成される面の表面粗さは溶液に含有される微粒子の大きさより粗くすればよいわけであるが、粗いとはいっても、本発明に使用される微粒子は大変微細なナノ微粒子であるため、その基板の表面粗さは視覚的には鏡面状態であり、基板を高精度に研摩する必要がある。あるいは、基板の表面にＳｉＯ_２等の薄膜を形成したような基板を使用する場合においても、その薄膜形成時（例えばスパッタリング等によって形成される）にも、表面のなめらかなＳｉＯ_２面を得るには、時間をかけて丁寧に膜形成を行う必要がある。すなわち、基板製造コストが高いということである。
【０１２８】
ところで本発明のパターン配線基板あるいは機能デバイス基板は、前述のように基板の片面にパターンを形成する構造のものであることを考慮すると、パターンを形成する面のみ、なめらかな面となった基板を使用すればよいことがわかる。つまり、基板の表面（パターンを形成する面）のみ、前述のような表面粗さとし、裏面はそれより粗い面にしても十分事足りる。
【０１２９】
言い換えるならば、本発明では基板のパターンを形成する面（おもて面）より裏面の表面粗さを粗くなるようにした基板を用いることにより、高精度なパターン配線基板あるいは機能デバイス基板が得られるとともに、基板製造コストを低くすることができるということである。例えば、おもて面（パターンを形成する面）より裏面粗さを１桁粗くする（例えばおもて面を０．０１ｓ〜０．０２ｓとした場合、裏面を０．１ｓ〜０．２ｓとする）だけで、基板製作コストは大幅に下がる。さらにそれ以上粗くすれば、実質的にはほとんどおもて面を良好な面とするだけのコストとなり、表裏両面を高精度に研摩した基板の半分近い製作コストとすることができる。ただし裏面粗さの上限であるが、いくらでもよいということではなく、一定の水準の工業製品としての品質を維持する必要はある。それについては以下で検討する。
【０１３０】
前述のように本発明は図２（あるいは図３）のような製造装置によってパターン配線基板あるいは機能デバイス基板を製造するが、製造プロセス時に基板裏面が製造装置の基板保持台（図２の１３）の基板保持面に密着して、移動させることができなくなるという製造時の不具合がある。この問題はちょうどブロックゲージがその表面のなめらかさを利用して、２つのブロックゲージをくっつける原理とよく似ている。要するに基板の裏面とそれに接触している基板保持面がなめらか過ぎてはずしにくくなるのである。
【０１３１】
その場合、どちらかの面（あるいは両方の面であってもいいが）の表面粗さを粗い状態にしてやれば解決できるが、本発明では、基板裏面を基板保持面の粗さ以下とし、基板保持面の方が粗いようにしている。
これは１つには、本発明によって製造されるパターン配線基板あるいは機能デバイス基板は、その後の利用方法も考えて、一定の水準の工業製品としての品質を維持する必要がある。すなわち裏面といえども一定の水準のなめらかさを維持することによって、工業製品としてのばらつきのない品質を維持するためである。
【０１３２】
２つには、基板裏面と基板保持面のどちらを粗くするほうが得策かという理由である。基板保持台１３は例えばＳＵＳ３０４等によって形成されるが、その基板保持面は使用中に傷が付いてきて表面が荒れた状態になることは避けられない。それならば、最初から表面粗さをなめらかにしてコストアップになるようなことはしないで、この面を粗くしておいたほうが得策である。なお、このＳＵＳ３０４等によって形成される基板保持面は、その面粗さに応じて、機械的な切削加工、研削加工、あるいはきさげ加工などによってその面を形成する。
【０１３３】
例をあげると、ＳＵＳ３０４よりなる基板保持面の粗さを研削加工によって０．５ｓ〜１ｓとし、使用する基板を石英ガラス（サイズ１００ｍｍ×１００ｍｍ）としその裏面の粗さが０．１ｓ〜０．２ｓとした場合、また、ＳＵＳ３０４よりなる基板保持面の粗さを切削加工によって２ｓ〜５ｓとし、使用する基板をＰＥＴフィルム（サイズ３００ｍｍ×３００ｍｍ）としその裏面の粗さが０．５ｓ〜１ｓとした場合に、基板が基板保持面にくっつくことなく、基板の取り外し交換作業がスムーズに行えた。すなわち、基板裏面の粗さを基板保持面の粗さ以下とすることにより、基板を移動させることができなくなる（基板の取り外し交換作業がしにくくなる）という製造時の不具合を避けることができるようになった。
【０１３４】
なお、基板保持台１３の基板保持面に微小な吸引孔を複数個形成し、真空吸引して基板を保持するような構成とした場合も、その吸引孔が形成されている面は、本発明の表面粗さを粗くしたものとみなされる。
【０１３５】
次に本発明のさらに他の特徴について説明する。本発明の機能を付与された基板は、無数の微細微粒子、ナノ微粒子を溶液中に分散させてなる微粒子含有溶液をインクジェットの原理で空中を飛翔させ、基板上に付与して製作されるものであるが、高品位な機能を付与された基板を長期にわたって安定して製作するためには、その製造装置が安定して一定の性能を維持するものでなくてはならない。ここで一番重要な点は噴射ヘッドの長期性能安定性である。
【０１３６】
前述のように本発明に使用する微粒子含有溶液は、液体に微粒子を分散させた溶液であるが、この微粒子は溶液中に分散している砥粒のような存在であり、この溶液を大量使用した場合、噴射ヘッドの溶液の通り道を損傷させたり、摩耗させたりするという問題がある。通り道の中でもとりわけ吐出口部（ノズル部）のキズや、摩耗は溶液の溶液噴射性能に影響を及ぼすため問題となる。
【０１３７】
ところでこのキズや、摩耗は、２つの物体が互いにぶつかり合う、あるいはこすれあう際に生ずるものであるから、互いの物体の硬さを適切に選ぶことにより、解決できるものと考えられる。またキズについても、これが噴射ヘッドの溶液噴射性能に影響を及ぼすのは事実ではあるが、どのくらい影響を及ぼすのかは、キズの大きさと溶液の通り道の大きさとによって決まると考えられる。たとえば、内径Φ１５ｍｍ〜Φ２０ｍｍの放水用のホースにナノメーターオーダーのキズがあったとしても、放水流量に多大な影響を及ぼすことはあり得ない。
【０１３８】
本発明ではこれらの点を考慮しながら、吐出口部の材質の硬さと、微粒子の材質の硬さならびに吐出口部の大きさを鋭意検討したものである。
使用した噴射ヘッドは、図７に示したようなサーマル方式（バブル方式）の液体噴射ヘッドの例であり、液滴噴射の原動力は、溶液中で瞬時に発生する膜沸騰気泡の成長作用力によるものである。
【０１３９】
なお図７では、流路がそのままノズル６６となる形式のものであるが、ここで使用したものは、ノズル６６面に別途ノズル孔を穿孔したノズルプレートを設けた構造とした噴射ヘッドを使用している。またそのノズル形状は丸とし、ノズル数を６４個、配列密度を４００ｄｐｉとしたものである。
【０１４０】
このような噴射ヘッドを使用し、一定時間溶液噴射を行うことにより、吐出口部（ノズル孔部）にキズが生じるかどうか、また、溶液吐出性能の劣化により、形成されるパターン形状（ドットパターンの形状良否）、パターン性能の劣化（抵抗値変化）が生じるかどうかを調べた。使用したパターンは、図１４（Ａ）のようなものである。マルチノズルプレートは、材料およびノズル径（ここでは丸形状とした）を変えたものを準備した。パターン性能は、噴射初期に形成したパターンと一定時間噴射を行った後に形成したパターンの抵抗値の違いを調べた。
【０１４１】
噴射ヘッドは、発熱体サイズが１０μｍ×４０μｍであり、その抵抗値は１０１Ωである。ヘッドの駆動電圧は１０Ｖであり、パルス幅は２μｓ、駆動周波数は１４ｋＨｚとした。この条件で７０時間連続噴射を行い、噴射後の吐出口部分をＳＥＭ観察して、キズの有無を調べた。吐出口径は、それぞれΦ２０μｍ、Φ１５μｍ、Φ１０μｍのものを用意した。
【０１４２】
比較参考例として、吐出口径がΦ３６μｍのもの（参考ヘッド）も用意した。この場合は、吐出口の数が４８個で、その配列密度が１８０ｄｐｉのものである。また発熱体サイズは３５μｍ×１８０μｍであり、その抵抗値は１２５Ωである。噴射ヘッドの駆動電圧は２８Ｖ、駆動周波数は３．５ｋＨｚとし、２８０時間連続噴射を行った。
【０１４３】
ノズルプレートの厚さは、吐出口径が、Φ２０μｍ、Φ１５μｍのものは３０μｍとし、Φ１０μｍのものは２０μｍ、参考ヘッドは４０μｍとした。噴射時の液滴の速度は、いずれの噴射ヘッドの場合も約１１ｍ／ｓとした。
【０１４４】
ノズルプレート材質はＮｉとオーステナイト系ステンレスＳＵＳ３０４とし、Ｎｉ材質のものはエレクトロフォーミング法でマルチノズルプレートを製作し、ＳＵＳ３０４材質のものは、ステンレス箔に放電加工によってノズル孔を穿孔した。それぞれ硬度をビッカース硬度計で測定したところ、Ｎｉ材質の場合はビッカース硬度Ｈｖが５８〜６３、ＳＵＳ３０４材質のものはビッカース硬度Ｈｖが１７０〜１９０であった。
【０１４５】
使用した液体は、前述のように微粒子を水を主体とする分散媒に分散せしめてなる水性系溶液である。微粒子は以下の７種類（Ｓ１〜Ｓ７）である。それぞれ含有微粒子の元素名と、そのバルク状態におけるビッカース硬度Ｈｖを示した。
【０１４６】
なおこのビッカース硬度Ｈｖは、金属データブック（日本金属学会編、改定３版、出版：丸善）の値を掲載した。それぞれの溶液における微粒子含有量は約８％とし、また微粒子径は０．０１μｍ〜０．０２μｍであった。
【０１４７】
【表７】

【０１４８】
これらのサンプル溶液および噴射ヘッドを使用して評価した結果を以下に示す。表中、キズの○は７０時間噴射後に、目立ったキズが確認できなかったもの、×はノズル形状、あるいは寸法にまでも影響をおよぼすような多数のすりキズが存在したものである。パターン形状の○は７０時間噴射後に、パターンを作製した際の、ドットパターンが狙いの位置（一対の電極間）に良好な丸い形状で形成されたもの（図１４（Ａ））であり、×は位置がやや狙いの場所から外れていたり、形状がいびつであったり、微小滴が周囲に飛散していたりしたもの（図１４（Ｂ））である。パターン性能の○×は、噴射初期に形成したパターンと一定時間噴射を行った後に形成したパターンの抵抗値の違いであり、○は７０時間噴射後にパターンを作製した際の抵抗値が、噴射初期に形成したパターンとほとんど同じであったもの（実用レベル）であり、×は７０時間噴射後にパターンを作製した際の抵抗値が異常に大きかったり、あるいは短絡していた場合（非実用レベル）である。なお、参考ヘッドの場合の噴射時間は２８０時間である。以下に結果を示す。
【０１４９】
【表８】

【０１５０】
【表９】

【０１５１】
【表１０】

【０１５２】
【表１１】

【０１５３】
以上の結果より、含有微粒子の硬度が、吐出口材質より大であるもの（Ｓ３、Ｓ６）の場合、吐出口に傷がつくことがわかる。またそれによって形成されたパターン形状は悪く、パターン性能も悪いことがわかる。よって、本発明のような製造装置によって、このようなパターンを形成する場合には、微粒子は吐出口を構成する部材よりやわらかい材料を選ぶ必要があることがわかる。
【０１５４】
なおそのキズに関しては、吐出口の大きさとの関係で、パターン形状が悪くならないものもある。参考ヘッドのように、吐出口径がΦ３６μｍもある（＝面積が約１０００μｍ^２）ような場合には、キズはついても吐出口径が大きいために、噴射性能を劣化に至らしめるほどのキズではなく、十分に使用可能なパターン形状が得られている。一方、吐出口径がΦ２０μｍ以下（＝面積が約３００μｍ^２以下）の場合のように、面積比較で参考ヘッドの１／３以下のような場合には、同じようにキズがついても、吐出口径との比較において与える影響は大であり、良好なパターン形状、パターン性能が得られないことがわかる。
【０１５５】
つまり、それほど微細なパターンを形成しないのであれば、キズの問題はパターン性能に影響を与えないので気にすることはないが、本発明のように、吐出口径Φ２０μｍ以下の液滴噴射ヘッドにより、微粒子径が０．０００５μｍ〜０．２μｍであるような微粒子を含有する溶液を噴射付与し、パターン形成を行うような場合には、吐出口部のキズは、パターン性能にとって致命的であるので、キズができないような溶液および吐出口部材の組み合わせを選ぶ必要がある。すなわち、微細微粒子は吐出口を構成する部材よりやわらかい材料とする必要がある。
【０１５６】
なお実験では、丸形状のΦ２０μｍノズル（面積が約３１４μｍ^２）、Φ１５μｍノズル（面積が約１７７μｍ^２）、Φ１０μｍノズル（面積が約７９μｍ^２）を使用したが、噴射ヘッドのノズルとして他の形状（たとえば矩形等）のものを使用する場合には、その面積比較をすればよく、たとえば、１８μｍ×１８μｍのノズルが、本発明の丸形状のΦ２０μｍノズルと同等となる。言い換えるならば、本発明は面積が約３００μｍ^２以下のノズルを使用した噴射ヘッドで、このような溶液を噴射してパターン形成する場合に適用されるものである。
【０１５７】
次に本発明のさらに他の特徴について説明する。本発明は、パターン配線基板あるいはデバイス基板を製作する技術であるが、形成されるパターンは、空気中を飛翔する微粒子含有溶液の噴射量を毎回同じにして噴射して基板上に形成される丸いドットパターンを形成し、それを組み合わせてパターン形成されるものである。
【０１５８】
本発明に適用される噴射ヘッドは、発熱体への入力エネルギーを変えることによって、その液滴のサイズあるいは飛翔液体の質量を変えることが可能である。しかしながら本発明では、使用する吐出口径がΦ２０μｍ以下という従来にない微細なノズルを使用し、そして噴射する溶液の量も大変微少なものである。よって、原理的には、噴射量を変えることはできるものの、安定した繰り返し噴射を行うためには、噴射量を変えるという複雑な制御を行うことは得策ではないので、いつも均一な同じ質量の溶液を噴射するようにしている。すなわち、噴射ヘッドの発熱体への入力エネルギーをいつも一定とし、同じ質量の溶液を繰り返し安定して噴射するようにしている。その結果、基板上に形成される丸いドットパターンも、前述のように、溶液飛翔時の形状を最適化したり、噴射速度や噴射ヘッドと基板との相対移動速度等を適切に選ぶ限り、良好な丸いドットパターンとして形成される。
【０１５９】
ところでこのような丸いドットパターンを組み合わせてパターン配線基板あるいはデバイス基板のパターンを形成する場合、パターン配線基板あるいはデバイス基板が電気回路あるいは電子デバイスとして機能するには、良好な丸いドットパターンのみならず、それらを組み合わせて形成されるパターンもその形状が良好である必要がある。
【０１６０】
図１７を使って説明する。図１７は、基板上に形成されている２つのＩＴＯ透明電極８２間に本発明の原理によって、微粒子含有溶液を噴射し、丸いドットパターン８３を形成し、パターン配線基板あるいはデバイス基板を形成する場合の模式的な図である。図中、Ｌｄは基板上にドットを単独で形成した場合のドット径であり、Ｐｄは隣接ドットの中心間距離（ドットピッチ）である。
【０１６１】
図１７（Ａ）は、２つのＩＴＯ透明電極間に３つのドットによるドットパターン８３を形成した場合であるが、形成（打ち込み）密度があらすぎて２つのＩＴＯ透明電極８２間を電気的に接続されない場合（Ｐｄ＞Ｌｄ）であり、この場合はいうまでもなくパターン配線基板あるいはデバイス基板として機能しない。図１７（Ｂ）は、各ドットが周辺部でかろうじて電気的に接続されている例である（Ｐｄ＝Ｌｄ）。図１７（Ｃ）は、図１７（Ｂ）の場合よりも、各ドットが周辺部で互いに重なり合って電気的に接続されている例である（Ｐｄ＜Ｌｄ）。図１７（Ｄ）、及び図１７（Ｅ）はさらにドットが重なり合う領域が大である場合である。
【０１６２】
ここで、単に電気的接続が得られるかどうかという観点から見ると、図１７（Ａ）は論外として、図１７（Ｂ）〜図１７（Ｅ）の場合は一応透明電極８２間を電気的に接続できている。しかしながら図１７（Ｂ）や図１７（Ｃ）の場合、丸いドットを横１列に組み合わせた。ドットパターン８３により形成された１本のラインパターンとしてみると、隣接ドット間（ドット８３が重なりあう領域）で、ラインパターン幅（図の縦方向の幅）が狭くなり、断線の危険性が大変高い。例えば図１７（Ｂ）のように各ドットが周辺部でかろうじて接続されているような場合は、一応は電気的に接続されているが、電気信号入力と同時に断線してしまい全く使いものにならない。また図１７（Ｃ）の場合においても同様の理由で、使用し始めの初期は使えても、長期的な使用には耐えない。
【０１６３】
本発明では、上記のような問題を解決するために、隣接ドット間に確実に１ドット以上重ねるようにしている。仮に図１７（Ｂ）の場合のように各ドットが周辺部でかろうじて接続されているような場合であっても、隣接ドット間の中央に１ドット重ねて形成すれば、その１ドットがない場合にラインパターン幅が最小値となる領域に１ドットを重ねるので、その領域のラインパターン幅は、最大値、すなわち１ドット分の幅（Ｌｄ）となる。
【０１６４】
このように隣接ドット間の中央に１ドット重ねて形成する条件は、別の表現をするならば、ドットを単独で形成した場合のドット径をＬｄとする時、Ｌｄ／２以下の密度で打ち込んで形成することである。
【０１６５】
またこのようにすると断線が生じない長期の信頼性に優れたラインパターンが形成できるのみならず、ラインパターンの輪郭も凹凸の少ないなめらかなものとなる。これは、図１７（Ｂ）、図１７（Ｃ）のように、丸いドットが電気的接続が得られる密度で打ち込まれているのみで、隣接ドット間に間を埋めるためのドットがない場合と、図１７（Ｄ）、図１７（Ｅ）のように、すでに電気的接続が得られる密度に加えて、隣接ドット間に間を埋めるためのドットを１ドット以上重ねて設けた場合を比較すれば、明白である。後者のほうがラインパターンの輪郭も凹凸の少ないなめらかなものとなり、ばらつきの少ない優れたパターン配線基板あるいはデバイス基板が得られる。
【０１６６】
なお、本発明は図１７に示すように、最終的なラインパターンが、液滴のドットを１列に配列して形成するような、本発明の製造装置によって形成できる一番細いパターンを形成する場合に適用されるものである。
【０１６７】
例えば、本発明の製造装置によって図１８に示すようなラインパターンも形成される。この場合は、横方向に１列にドットを配列したものを３本ならべて比較的太いライン幅を得るようにした例である。またこの例は、図１７（Ｃ）の配列例で３本ならべて太いラインパターンが得られるようにしたものである。つまり、１本だけでは断線が生じる場合の例である。
【０１６８】
しかしながらこのようにドットを３本（２本であってもよい）ならべているため、断線は生じることなく良好に機能する。よってこのように複数本（この例では３本）のドットをならべたような場合には、丸いドットが電気的接続が得られる密度で打ち込まれているのみで、隣接ドット間に間を埋めるためのドットがなくても、縦方向（ラインパターン幅方向）に複数本ならべているので断線の危険性はない。
【０１６９】
すなわち本発明のように隣接ドット間に間を埋めるためのドットを１ドット以上重ねて設けるという条件は、微細パターンを形成するために液滴のドットを１列に配列して形成するような場合に適用しなければならない条件である。
【０１７０】
以上の説明から明らかなように、本発明は、パターン配線基板あるいはデバイス基板を製作する技術であるが、数１０μｍ〜数μｍという非常に微細なパターンを従来のようなフォトリソ技術によるのではなく、従来にはない微小な吐出口を有する噴射ヘッドによって微粒子含有溶液の液滴を基板に直接噴射付与するという簡単な装置で、パターンやデバイスをダイレクト製作するようにしている。したがって、いわゆる半導体製造プロセスで使用されている高価な製造装置を必要とせず、低コストでかつ安定して製作できるようになった。
【０１７１】
【発明の効果】
吐出口径がΦ２０μｍ以下の噴射ヘッドによって微粒子含有溶液を噴射付与し、パターン配線基板あるいはデバイス基板を製造する溶液噴射製造装置において、基板の表面粗さと微粒子の大きさの関係を最適化することにより、高精度なパターン形成を実現した。また、微粒子の大きさと吐出口径を最適化し、目詰まりのない安定した噴射を実現するとともに、良好なドットを形成しやすい溶液を噴射、形成するようにし、さらにその溶液の噴射速度と、基板と噴射ヘッドとの相対移動速度との関係を最適化し、吐出口材質と使用する微粒子の硬さを最適化したので、新規な手法による高精度かつ高品質なパターン配線基板あるいはデバイス基板を低コストでかつ安定して製作できるようになった。さらに溶液のドットを同じ溶液量で形成し、その打ち込み密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンを得ることができるようになった。
【０１７２】
また、吐出口径がΦ２０μｍ以下の噴射ヘッドによって微粒子含有溶液を噴射付与し、パターン配線基板あるいはデバイス基板を製造する溶液噴射製造装置において、基板の表面粗さと微粒子の大きさの関係を最適化することにより、高精度なパターン形成を実現した。また、微粒子の大きさと吐出口径を最適化し、目詰まりのない安定した噴射を実現するとともに、良好なドットを形成しやすい溶液を噴射、形成するようにし、さらにその溶液の噴射速度と、基板と噴射ヘッドとの相対移動速度との関係を最適化、かつ噴射速度を高速化する条件とし、吐出口材質と使用する微粒子の硬さを最適化したので、新規な手法によるより高精度かつ高品質なパターン配線基板あるいはデバイス基板を低コストでかつ安定して製作できるようになった。さらに溶液のドットを同じ溶液量で形成し、その打ち込み密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンを得ることができるようになった。
【０１７３】
また、上記のような溶液噴射製造装置によって製作されるパターン配線基板において、形成されたパターン中の微粒子は吐出口を構成する部材よりやわらかい材料よりなるようにしたので、噴射ヘッドの吐出口をキズつけたり、摩耗させたりして、その噴射性能劣化を引き起こすということが皆無となった。また、その微粒子と基板の表面粗さの関係を最適化したので、高精度なパターン形成を実現できた。さらに溶液のドットを同じ溶液量で形成し、配列密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンを得ることができるようになった。
【０１７４】
また、上記のような溶液噴射製造装置によって製作されるパターン配線基板において、形成されたパターン中の微粒子は吐出口を構成する部材よりやわらかい材料よりなるようにしたので、噴射ヘッドの吐出口をキズつけたり、摩耗させたりして、その噴射性能劣化を引き起こすということが皆無となった。また、その微粒子と基板の表面粗さの関係を最適化したので、高精度なパターン形成を実現できた。さらに基板の裏面の表面粗さをパターンが形成される面の表面粗さより粗くしかつ溶液噴射製造装置の基板を保持する保持面の粗さ以下として、基板ならびに製造装置製作時の低コスト化を実現した。また、裏面の表面粗さより基板を保持する保持面の粗さが大であるため、このようなパターン配線基板を製造する際に、基板裏面が製造装置の基板保持面に密着して、移動させることができなくなるという製造時の不具合が生じなくなり、大変歩留まりよく製造できるようになった。さらに微粒子の大きさと吐出口径を最適化したので、目詰まりのない安定した噴射によって製造でき、かつ高精度なパターン形成を実現した。また、溶液のドットを同じ溶液量で形成し、配列密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンを得ることができるようになった。
【０１７５】
また、上記のような溶液噴射製造装置によって製作されるデバイス基板において、形成されたパターン中の微粒子は吐出口を構成する部材よりやわらかい材料よりなるようにしたので、噴射ヘッドの吐出口をキズつけたり、摩耗させたりして、その噴射性能劣化を引き起こすということが皆無となった。また、その微粒子と基板の表面粗さの関係を最適化したので、高精度なデバイス基板を実現できた。さらに溶液のドットを同じ溶液量で形成し、配列密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンのデバイス基板を得ることができるようになった。
【０１７６】
また、上記のような溶液噴射製造装置によって製作されるデバイス基板において、形成されたパターン中の微粒子は吐出口を構成する部材よりやわらかい材料よりなるようにしたので、噴射ヘッドの吐出口をキズつけたり、摩耗させたりして、その噴射性能劣化を引き起こすということが皆無となった。また、その微粒子と基板の表面粗さの関係を最適化したので、高精度なデバイス基板を実現できた。さらに基板の裏面の表面粗さをデバイスのパターンが形成される面の表面粗さより粗くしかつ溶液噴射製造装置の基板を保持する保持面の粗さ以下として、基板ならびに製造装置製作時の低コスト化を実現した。また、裏面の表面粗さより基板を保持する保持面の粗さが大であるため、このようなデバイス基板を製造する際に、基板裏面が製造装置の基板保持面に密着して、移動させることができなくなるという製造時の不具合が生じなくなり、大変歩留まりよく製造できるようになった。さらに微粒子の大きさと吐出口径を最適化したので、目詰まりのない安定した噴射によって製造でき、かつ高精度なデバイス基板を実現した。また、溶液のドットを同じ溶液量で形成し、配列密度も最適化したので、ドットが１列に配列された微細なパターンであっても、良好な品質かつ性能の長期の信頼性に優れたパターンのデバイス基板を得ることができるようになった。
【図面の簡単な説明】
【図１】本発明の溶液噴射製造装置によって形成されるパターン配線の一実施例を説明するための図である。
【図２】本発明のパターン配線基板あるいはデバイス基板を製造する溶液噴射製造装置の一実施例を説明するための図である。
【図３】本発明のパターン配線基板あるいはデバイス基板を製造する溶液噴射製造装置の他の実施例を説明するための図である。
【図４】本発明のパターン配線基板あるいはデバイス基板の製造に適用される溶液付与装置を示す概略構成図である。
【図５】ピエゾ素子利用の噴射ヘッドの液滴噴射原理を説明する図である。
【図６】ピエゾ素子利用の噴射ヘッドの構造を示す図である。
【図７】本発明に好適に適用されるサーマル方式（バブル方式）の液体噴射ヘッドの例である。
【図８】マルチノズル型の液体噴射ヘッドをノズル側から見た図である。
【図９】マルチノズル型の液体噴射ヘッドを噴射する溶液ごとに積層し、ユニット化した図である。
【図１０】ユニット化したヘッドの斜視図ある。
【図１１】本発明の溶液噴射製造装置に使用される噴射ヘッドで膜沸騰気泡による作用力で噴射した場合の溶液飛翔形状の例を説明するための図である。
【図１２】本発明の溶液噴射製造装置に使用される噴射ヘッドで機械的変位による作用力で噴射した場合の液滴飛翔形状の例を説明するための図である。
【図１３】本発明の溶液噴射製造装置に使用される噴射ヘッドで機械的変位による作用力で噴射した場合の他の液滴飛翔形状の例を説明するための図である。
【図１４】本発明の溶液噴射製造装置によって、良好なパターン形成を行う条件を見出すために使用したテストパターンの例を示す図である。
【図１５】基板の表面粗さより大である微粒子を含有した溶液によってドットパターンを形成した場合の、微粒子と表面粗さの関係を模式的に示した図である。
【図１６】基板の表面粗さ以下の大きさの微粒子を含有した溶液によってドットパターンを形成した場合の、微粒子と表面粗さの関係を模式的に示した図である。
【図１７】液滴のドットを１列に配列して微細ラインパターンを形成する例を説明するための図である。
【図１８】液滴のドット列を複数列配列して太いラインパターンを形成する例を説明するための図である。
【符号の説明】
１…配線パターン、２，３…端子、１０…基板、１１…吐出ヘッドユニット（噴射ヘッド）、１２…キャリッジ、１３…基板保持台、１４…基板、１５…供給チューブ、１６…信号供給ケーブル、１７…噴射ヘッドコントロールボックス、１８…Ｘ方向スキャンモータ、１９…Ｙ方向スキャンモータ、２０…コンピュータ、２１…コントロールボックス、２２…基板位置決め／保持手段、３１…ヘッドアライメント制御機構、３２…検出光学系、３３…噴射ヘッド、３４…ヘッドアライメント微動機構、３５…制御用コンピュータ、３６…画像識別機構、３７…ＸＹ方向走査機構、３８…位置検出機構、３９…位置補正制御機構、４０…噴射ヘッド駆動・制御機構、４１…光軸、４２…素子電極、４３…液滴、４４…着弾位置、４５…流路、４６…ピエゾ素子、４７…溶液、４８…ノズル、４９…フィルター、６５…ノズル、６６…発熱体基板、６７…蓋基板、６８…シリコン基板、６９…個別電極、７０…共通電極、７１…発熱体、７４…溝、７５…凹部領域、７６…溶液流入口、８１…サテライト微小滴、８２…素子電極（ＩＴＯ透明電極）、８３…ドットパターン、８４…微小滴、８５…微粒子、６３…基板表面。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for forming a wiring substrate or a functional device by ejecting a material containing fine particles by using an ejection device to form a pattern, a material used for the same, and a pattern substrate or a functional device substrate formed by the apparatus. .
[0002]
[Prior art]
In recent years, various devices such as a light-emitting device / medium and an optical processing device / medium using fine particles / ultrafine particles have been studied. For application of such fine particles to an element, high-density integration obtained by depositing a film or layer of a fine particle-containing material on a solid substrate is important. The thin film in which the fine particles are integrated at a high density is specifically reported to be applied to Non-Patent Documents 1 to 6 and the like.
[0003]
On the other hand, as a method of forming an inorganic compound thin film having excellent orientation, a molecular beam epitaxy method (MBE), a cluster ion beam method, an ion beam irradiation vacuum deposition method, a chemical vapor deposition method (CVD), and a physical vapor deposition method ( PVD), liquid phase epitaxy (LPE) and the like are known. As a method for forming an organic compound thin film, a Langmuir-Blodgett method (LB method) and the like are known. What is generally called a quantum dot can be manufactured by utilizing a process in which a raw material sublimated in a high vacuum using a vacuum apparatus such as the MBE method described above forms dots in a self-organizing manner on a solid substrate. it can.
[0004]
However, in the above method, it is difficult to control the distance between dots and the size distribution, and there is a problem that a great deal of cost is required to control to a desired structure. Therefore, as a technique capable of solving such a problem, it has been proposed to form a film of a material containing fine particles by the ink jet principle, that is, by a liquid jet head. For example, Patent Literature 1 discloses an ultra-violet light having an ability to inkjet-coat an emulsion containing nanoparticles on a solid substrate and increase or increase and memorize the photoluminescence intensity as a function of the irradiation time or irradiation amount of the excitation light. A method of forming a thin film composed of an aggregate of fine particles (nanoparticles) on a solid substrate has been proposed.
[0005]
In addition, studies have been made to apply the same principle to the fabrication of circuit boards in addition to such functional elements. For example, the following method is conventionally known as a method for manufacturing a circuit board.
[0006]
(1) A method in which a resist is coated on a copper-clad laminate, and a photolithography method is used to form a copper wire pattern by exposing a circuit pattern, dissolving and removing an unexposed resist, and etching a resist-removed portion.
(2) A method in which a conductive paste is printed in a desired circuit pattern on a ceramic substrate by screen printing, and heat treatment is performed in a non-oxidizing atmosphere to sinter metal fine particles in the conductive paste to form a conductive pattern.
(3) A thin conductive layer is formed on the insulating substrate by vapor deposition of a conductive metal, a resist is coated on the conductive layer, and a circuit pattern is exposed by a photolithography method, and the unexposed resist is dissolved and removed. A method of forming a copper wire pattern by etching a removed portion.
[0007]
However, these methods have a problem that they are not suitable for forming a fine pattern. For example, Patent Document 2 discloses that a circuit pattern is directly drawn on a substrate by a metal paste using an inkjet head. A method of forming a wiring pattern and a method of manufacturing a circuit board have been proposed in which a fine pattern can be easily formed, no waste liquid treatment is required, a production process is simple, and equipment costs and production costs can be reduced.
On the other hand, the present inventor has already proposed as Patent Document 3 an invention of manufacturing an electron source substrate using the ink jet principle.
[0008]
As described above, various proposals using the ink jet principle have begun to be made, but the idea of manufacturing various devices or pattern substrates by such means is still new, and a more specific method is still unknown. It is a fact that there are many parts and it is in a fumbling state.
[0009]
[Patent Document 1]
JP 2000-126681 A
[Patent Document 2]
JP 2002-134878 A
[Patent Document 3]
JP 2001-319567 A
[Non-patent document 1]
Light-emitting elements (LEDs) (Alivisatos et al.)
[Non-patent document 2]
Photoelectric conversion element (Greenham, NC, et al., Phys. Rev. B, 54, 17628 (1996))
[Non-Patent Document 3]
Ultra high speed detector (Bhargava)
[Non-patent document 4]
Electroluminescent displays and panels (Bhargava, Alivisatos et al.)
[Non-Patent Document 5]
Nanostructured memory devices (Chen et al.)
[Non-Patent Document 6]
Multicolor devices consisting of nanoparticle arrays (Dushkin et al.)
[0010]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a first object of the present invention is to provide a novel solution jet manufacturing apparatus for manufacturing high quality, high precision, fine pattern wiring boards or device substrates with high yield. To provide.
[0011]
It is a second object of the present invention to provide a solution jet manufacturing apparatus having another configuration for manufacturing a high-quality, high-precision, fine pattern wiring substrate or device substrate with a high yield.
[0012]
Further, a third object is to provide a fine pattern wiring board provided with high-precision and high-quality functions manufactured by the solution jet manufacturing apparatus having such a novel configuration.
[0013]
A fourth object of the present invention is to provide a fine pattern wiring board provided with higher precision and higher quality functions manufactured by the solution jet manufacturing apparatus having such a novel configuration.
[0014]
A fifth object is to provide a fine device substrate provided with high-precision and high-quality functions manufactured by the solution jet manufacturing apparatus having such a novel configuration.
[0015]
A sixth object is to provide a fine device substrate provided with higher precision and higher quality functions manufactured by the solution jet manufacturing apparatus having such a novel configuration.
[0016]
[Means for Solving the Problems]
First, in order to achieve the above object, the present invention sprays and applies a fine particle-containing solution onto a substrate by an ejection head having a discharge port diameter of Φ20 μm or less, forms a pattern on the substrate and on the electrode region, In a solution jet manufacturing apparatus for forming a pattern wiring or a device by volatilizing volatile components in a pattern formed by a solution and leaving a solid content on the substrate as well as on an electrode region, the pattern of the substrate is formed. When the surface roughness of the surface is larger than the size of the fine particles, and the size of the fine particles is Dp and the discharge port diameter is Do, 0.0001 ≦ Dp / Do ≦ 0.01; Injecting the solution by the growth action force of the film boiling bubbles generated instantaneously in the solution, and changing the shape of the solution during flight in the flight direction. An elongated columnar shape having a length of at least 5 times the diameter thereof, a relative moving speed between the substrate and the ejection head being set to 1/3 or less of an ejection speed of the solution, and the discharge port containing the fine particles. A solution jet manufacturing apparatus, which is an opening formed in a substrate made of a material harder than fine particles in a solution, wherein the pattern formed by the solution jet manufacturing apparatus has dots formed by the solution arranged in a line. In this case, the dots of the solution are formed with the same amount of solution, and when the dot diameter is Ld when the dots are independently formed, the dots are formed by being driven at a density of Ld / 2 or less.
[0017]
Secondly, a solution containing fine particles is sprayed onto the substrate by a spray head having a discharge opening diameter of Φ20 μm or less to form a pattern on the substrate and the electrode region, and volatilization in the pattern formed by the solution after application is performed. In a solution jet manufacturing apparatus for forming a pattern wiring or a device by volatilizing a component and leaving a solid content on the substrate and the electrode region, the surface roughness of the surface of the substrate on which the pattern is formed is reduced by the fine particles. When the size of the fine particles is set to Dp and the discharge port diameter is set to Do, 0.0001 ≦ Dp / Do ≦ 0.01, and the ejection head instantaneously generates in the solution. The solution is jetted by the action of the growth of the film boiling bubbles, and the shape of the solution at the time of flight is an elongated columnar shape extending in the flight direction, The length is at least five times the diameter, the relative movement speed between the substrate and the ejection head is set to 1/3 or less of the ejection speed of the solution, and the solution at the time of the elongated columnar flight is moved backward by a plurality of minute A high-speed flying with droplets, wherein the discharge port is an opening formed in a substrate made of a material harder than the fine particles in the fine particle-containing solution. When the pattern is formed by arranging the dots formed by the solution in one row, the dots of the solution are formed with the same amount of the solution, and when the dot diameter when the dots are formed alone is Ld, It was formed by driving at a density of Ld / 2 or less.
[0018]
Thirdly, a fine particle-containing solution is jetted onto the substrate by a jetting head having a discharge diameter of Φ20 μm or less by the growth action of a film boiling bubble generated instantaneously in the solution, and the shape at the time of solution flight is changed. A slender column extending in the flight direction and having a length of 5 times or more its diameter, flying at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, In a pattern wiring board provided with a function manufactured by a solution jet manufacturing apparatus for forming a pattern wiring or a device, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern wiring board is A pattern wiring board in which the surface on which the pattern is formed is roughened more than the size of the fine particles, wherein the pattern is When the dots formed by the solution are arranged in a line, the dots of the solution are formed in the same amount of solution, and when the dot diameter when the dots are formed alone is Ld, Ld / 2 or less.
[0019]
Fourthly, a fine particle-containing solution is jetted onto the substrate by a jetting head having a discharge diameter of Φ20 μm or less by a growth action force of a film boiling bubble generated instantaneously in the solution, and the shape at the time of solution flying is changed. A slender column extending in the flight direction and having a length of 5 times or more its diameter, flying at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, In a pattern wiring board provided with a function manufactured by a solution jet manufacturing apparatus for forming a pattern wiring or a device, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern wiring board is The surface roughness of the surface on which the pattern is formed is larger than the size of the fine particles, and the surface roughness of the back surface of the pattern wiring substrate is reduced by the pattern. The roughness of the surface on which the pattern is formed is not more than the roughness of the holding surface for holding the pattern wiring substrate of the solution jet manufacturing apparatus, and the size of the fine particles in the pattern is Dp, When the aperture is Do, the pattern wiring board satisfies 0.0001 ≦ Dp / Do ≦ 0.01, wherein the pattern is formed by arranging dots formed by the solution in one row. When the dots of the solution are formed with the same amount of solution, and the dot diameter is Ld when the dots are formed alone, the dots are formed by being driven at a density of Ld / 2 or less.
[0020]
Fifthly, while ejecting the fine particle-containing solution onto the substrate by the ejection head having a diameter of Φ20 μm or less by the growth action of the film boiling bubbles generated instantaneously in the solution, the shape at the time of the solution flying, A slender column extending in the flight direction and having a length of 5 times or more its diameter, flying at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, In a device substrate provided with a function manufactured by a solution jet manufacturing apparatus for forming a pattern wiring or a device, fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the device substrate A device substrate in which the surface on which a pattern is formed has a surface roughness greater than the size of the fine particles, wherein the pattern is formed with the solution. When the dots to be formed are formed in a line, the dots of the solution are formed with the same amount of solution, and when the dot diameter when the dots are formed alone is Ld, Ld / 2 or less is used. It was formed by driving at a density.
[0021]
Sixth, a fine particle-containing solution is jetted onto a substrate by a jet head having a discharge diameter of Φ20 μm or less by the growth action of film boiling bubbles instantaneously generated in the solution, and the shape at the time of solution flight is A slender column extending in the flight direction and having a length of 5 times or more its diameter, flying at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, In a device substrate provided with a function manufactured by a solution jet manufacturing apparatus for forming a pattern wiring or a device, fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the device substrate The surface roughness of the surface on which the pattern is formed is made larger than the size of the fine particles, and the surface roughness of the back surface of the substrate is reduced on the surface on which the pattern is formed. When the size of the fine particles in the pattern is set to Dp and the discharge port diameter is set to 0. 0, the surface roughness is set to be larger than the surface roughness and not more than the roughness of the holding surface for holding the device substrate of the solution jet manufacturing apparatus. 0001 ≦ Dp / Do ≦ 0.01, wherein the pattern is such that, when dots formed by the solution are arranged in a line, the dots of the solution are formed in the same amount of solution. When the dots are formed independently and the dot diameter is Ld, the dots are formed at a density of Ld / 2 or less.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an example in which a pattern is formed on a glass substrate, a plastic substrate, a semiconductor substrate such as Si, a glass / epoxy substrate, a flexible substrate, and the like by the method of the present invention. FIG. 1A shows a state in which terminals 2 and 3 are formed on such a substrate 10, and a dotted line portion 1 'in the figure is an area where a wiring pattern as described later is generated. FIG. 1B shows an example in which a solution containing fine conductive fine particles is ejected and drawn according to the droplet ejection principle to form a wiring pattern 1.
Here, in the present invention, an ink jet technique is applied as a means for applying a solution containing fine conductive fine particles. The specific method will be described below.
[0023]
FIG. 2 is a view for explaining an embodiment of a manufacturing apparatus for forming a pattern wiring board or a functional device according to the present invention. In the figure, 11 is an ejection head unit (ejection head), 12 is a carriage, and 13 is a carriage. A substrate holder, 14 a substrate such as a wiring substrate or a functional element substrate or a substrate forming a functional device, 15 a supply tube for a solution containing fine conductive fine particles, 16 a signal supply cable, 17 a jet head A control box (including a solution tank), 18 is an X-direction scan motor of the carriage 12, 19 is a Y-direction scan motor of the carriage 12, 20 is a computer, 21 is a control box, and 22 (22) _X1 , 22 _Y1 , 22 _X2 , 22 _Y2 ) Is a substrate positioning / holding means. In this case, the ejection head 11 is moved by carriage scanning on the front surface of the substrate 14 placed on the substrate holding table 13 to eject a solution containing fine conductive fine particles.
[0024]
FIG. 3 is a schematic view showing the configuration of a droplet applying apparatus applied to the manufacture of a patterned wiring substrate or the formation of a functional device according to the present invention, and FIG. 4 is a schematic diagram of a main part of an ejection head unit of the droplet applying apparatus of FIG. It is a block diagram.
The configuration in FIG. 3 differs from the configuration in FIG. 2 in that a wiring pattern or a functional device is formed on the substrate by moving the substrate 14 side. 3 and 4, 31 is a head alignment control mechanism, 32 is a detection optical system, 33 is an ejection head, 34 is a head alignment fine movement mechanism, 36 is an image identification mechanism, 37 is an XY scanning mechanism, and 38 is a position detection mechanism. , 39 is a position correction control mechanism, 40 is an ejection head drive / control mechanism, 41 is an optical axis, 42 is an element electrode, 43 is a droplet, and 44 is a droplet landing position.
[0025]
The droplet applying device (ejection head 33) of the ejection head unit 11 may be any mechanism as long as it can discharge a given amount of droplets in a fixed amount, and in particular, an ink jet principle capable of forming droplets of about 0.1 pl to several hundred pl Mechanism is desirable.
[0026]
Examples of the ink jet system include a system disclosed in US Pat. No. 3,683,212 (Zoltan system), a system disclosed in US Pat. No. 3,747,120 (Stemme system), and US Pat. No. 3,946,398. An electric signal is applied to the piezoelectric vibrating element as in the disclosed method (Kyser method), and this electric signal is converted into mechanical vibration of the piezoelectric vibrating element, and a droplet is discharged from a fine nozzle according to the mechanical vibration. Is ejected, and is generally called a drop-on-demand system.
[0027]
As another method, there is a method (Sweet method) disclosed in US Pat. No. 3,596,275, US Pat. No. 3,298,030, and the like. This generates droplets of the recording liquid whose charge amount is controlled by the continuous vibration generation method, and the generated droplets whose charge amount is controlled fly between the deflection electrodes to which a uniform electric field is applied. By doing so, recording is performed on the recording member, which is usually called a continuous flow method or a charge control method.
[0028]
As another method, there is a method disclosed in Japanese Patent Publication No. 56-9429. In this method, bubbles are generated in a liquid, and droplets are ejected and fly from a fine nozzle by the action force of the bubbles. This is called a thermal ink jet system or a bubble jet (R) system.
[0029]
The method of ejecting the droplets in this way includes a drop-on-demand method, a continuous flow method, a thermal ink jet method, and the like, and the method may be appropriately selected as needed.
[0030]
In the present invention, in a manufacturing apparatus (FIG. 2) for forming such a pattern wiring substrate or a functional device, the substrate 14 is determined by adjusting the holding position by the substrate positioning / holding means 22 of the apparatus. Although simplified in FIG. 2, the substrate positioning / holding means 22 is in contact with each side of the substrate 14 and can be finely adjusted in the X direction and the Y direction orthogonal thereto in the order of submicrons. The control unit is connected to the ejection head control box 17, the computer 20, the control box 21, and the like, so that the positioning information and the fine adjustment displacement information and the like, and the position information and timing of the droplet application can be constantly fed back.
[0031]
Further, in the manufacturing apparatus for forming a patterned wiring board or a functional device according to the present invention, in addition to the position adjustment mechanism in the X and Y directions, a rotation position adjustment mechanism (not shown because it is located below the substrate 14) is provided. Have. In this regard, the shape of the pattern wiring substrate or the functional device forming substrate of the present invention, the arrangement of the functional device groups to be formed, and the like will be described first.
[0032]
The pattern wiring substrate or the functional device forming substrate of the present invention may be a glass substrate, a ceramic substrate, various plastic substrates such as PET, a semiconductor substrate such as Si, a glass / epoxy substrate, a polyimide film, depending on its purpose and application. A flexible substrate made of a polymer film such as a polyamideimide film, a polyamide film, and a polyester film is preferably used. For example, various plastic substrates and polymer films are effective for patterned wiring boards or functional devices that require light weight.
[0033]
The shapes of various plastic substrates and polymer fills used for the pattern wiring substrate or the functional device forming substrate of the present invention are economical to produce and supply such a substrate, or to finally produce a functional device forming substrate It is rectangular because of the use. That is, each of the two vertical and horizontal sides constituting the rectangular shape is a substrate in which two vertical sides are parallel to each other, two horizontal sides are parallel to each other, and the vertical and horizontal sides are at right angles.
[0034]
In the present invention, a group of functional devices to be formed is arranged in a matrix on such a substrate, and two directions orthogonal to each other in the matrix are parallel to the direction of the vertical side or the horizontal side of the substrate. The functional device group is arranged as follows. The reason for arranging the functional device groups in a matrix and the reason for making the vertical and horizontal sides of the substrate parallel to two orthogonal directions of the matrix will be described below.
[0035]
As shown in FIG. 2 or FIG. 3, according to the present invention, after the positional relationship between the substrate 14 and the solution ejection surface of the ejection head unit 11 is determined first, no particular position control is performed. In other words, the ejection head unit 11 ejects the solution while performing relative movement in the X and Y directions in parallel with the functional device group formation surface while keeping a certain distance from the substrate 14. In other words, the X direction and the Y direction are two directions orthogonal to each other. When positioning the substrate, the vertical or horizontal side of the substrate is set so as to be parallel to the Y direction or the X direction. Since the two functional device groups are parallel in the two directions of the matrix arrangement, the device groups can be formed with high accuracy only by the mechanism that performs the relative movement and the ejection. In other words, if the substrate shape as in the present invention, the matrix arrangement of functional device groups, and the relative movement device in two orthogonal X and Y directions are used, the positioning of the substrate before performing the droplet formation for device formation can be performed. If done correctly, a high-precision matrix-like array of functional devices can be obtained.
[0036]
Here, the description will return to the rotation position adjustment mechanism described above. As described above, in the present invention, a highly accurate functional device group can be accurately positioned without performing the relative movement in the X and Y directions without performing the relative movement in the X and Y directions before performing the droplet ejection for device formation. In order to obtain a matrix-like arrangement. In this case, a problem is a deviation in a rotation direction (a rotation direction with respect to an axis perpendicular to a plane determined by the two directions X and Y) when the substrate is first positioned.
[0037]
In order to correct the deviation in the rotation direction, the present invention has a rotation position adjustment mechanism (not shown but located below the substrate 14) as described above. Accordingly, when the displacement in the rotation direction is also corrected and the side of the substrate is positioned, the apparatus of the present invention can obtain a high-precision matrix of functional device groups by relative movement only in the X and Y directions.
[0038]
As described above, the rotation position adjusting mechanism is connected to the substrate positioning / holding unit 22 in FIG. _X1 , 22 _Y1 , 22 _X2 , 22 _Y2 Although described as a mechanism separate from () and not visible under the substrate 14, the substrate positioning / holding means 22 may have a rotation position adjusting mechanism. For example, the substrate positioning / holding unit 22 is in contact with the side of the substrate 14 so that the position of the entire substrate positioning / holding unit 22 can be adjusted in the X direction or the Y direction. The angle can be adjusted by allowing two screws provided at a distance to move independently of each other at a portion of the substrate 22 that is in contact with the side of the substrate 14. The rotation position control information is also connected to the ejection head control box 17, the computer 20, the control box 21 and the like in the same manner as the above-described positioning information in the X and Y directions and the fine adjustment displacement information. Timing and the like can be constantly fed back.
[0039]
The above description is based on the premise that the substrate preferably used in the present invention is basically rectangular, except that a semiconductor substrate such as Si is supplied as a round wafer, In this case, one side of a straight line called an orientation flat (orientation flat) indicating the direction of the crystal orientation axis may be brought into contact with the substrate positioning / holding means 22.
[0040]
Next, another means and configuration of the positioning of the present invention will be described. In the above description, the substrate positioning / holding means 22 is in contact with the side of the substrate 14 so that the position of the entire substrate positioning / holding means 22 can be adjusted in the X direction or the Y direction. A description will be given of an example in which strip patterns are provided not in the sides of the substrate 14 but in two directions orthogonal to each other on the substrate. As described above, in the present invention, the functional device groups are formed on the substrate by arranging them in a matrix. It is formed so as to be parallel. Such a pattern can be easily formed on a substrate by a photofabrication technique.
[0041]
The present invention is applied not only to the case of forming a large number of functional device groups arranged in a matrix but also to the case of forming a wiring pattern as shown in FIG. As in this example, they are formed in two orthogonal directions, and are formed so as to be parallel to the vertical and horizontal directions (X direction, Y direction) of the substrate, respectively. This wiring pattern may be formed as a pattern for such a positioning purpose at a position where the original function of the substrate of the present invention is not impaired, or may be formed as a device electrode 42 (FIG. 4) or each device. The wiring pattern such as the X-direction wiring and the Y-direction wiring may be regarded as a two-way strip pattern perpendicular to each other in the present invention. If such a band-shaped pattern is provided, the pattern can be detected by the detection optical system 32 using a CCD camera and a lens as described later with reference to FIG.
[0042]
Next, in the Z direction which is a direction perpendicular to the X and Y directions, according to the present invention, after the positional relationship between the substrate 14 and the solution ejection surface of the ejection head unit 11 is determined first, the position is particularly large. There is no control. In other words, the ejection head unit 11 performs the relative movement in the X and Y directions while maintaining a certain distance (1 to 3 mm) with respect to the substrate 14, and ejects the solution containing fine conductive fine particles. At the time of ejection, the position control of the ejection head unit 11 in the Z direction is not particularly performed. The reason is that if the control is performed at the time of ejection, not only the mechanism, the control system, and the like become complicated, but also the formation of the functional device by applying the droplets to the substrate 14 is delayed, and the productivity is significantly reduced. .
[0043]
Instead, in the present invention, the flatness of the substrate 14, the flatness of the device holding the substrate 14, and the accuracy of a carriage mechanism for relatively moving the ejection head unit 11 in the X and Y directions are improved. Thus, the relative movement of the ejection head unit 11 and the substrate 14 in the X and Y directions is performed at a high speed without performing the Z-direction control at the time of ejection, thereby improving productivity. As an example, the variation in the distance between the substrate 14 and the solution ejection surface of the ejection head unit 11 when applying the solution of the present invention (during ejection) is suppressed to 2 mm or less (the size of the substrate 14 is 100 mm × 100 mm or more). , 4000 mm x 4000 mm or less).
[0044]
Note that the device is usually configured so that the plane determined by the two directions of the X and Y directions is kept horizontal (a plane perpendicular to the vertical direction), but when the substrate 14 is small (for example, 500 mm × 500 mm or less). In (2), it is not always necessary to make a plane determined by the two directions of X and Y horizontal, and it is only necessary to make the positional relationship of the substrate 14 most efficient for the device.
[0045]
Next, the configuration of the ejection head unit 11 will be described with reference to FIG. In FIG. 4, reference numeral 32 denotes a detection optical system that captures image information on the substrate 14, which is close to the ejection head 33 that ejects the droplet 43, The droplets 43 are arranged so that the landing positions 44 of the droplets 43 coincide with each other.
[0046]
In this case, the positional relationship between the detection optical system 32 and the ejection head 33 shown in FIG. 3 can be precisely adjusted by the head alignment fine movement mechanism 34 and the head alignment control mechanism 31. The detection optical system 32 uses a CCD camera and a lens.
[0047]
In FIG. 3, reference numeral 36 denotes an image identification mechanism for identifying the image information captured by the detection optical system 32, and has a function of binarizing the contrast of the image and calculating the position of the center of gravity of the binarized specific contrast portion. It had. Specifically, a high-precision image recognition device VX-4210 manufactured by KEYENCE CORPORATION can be used. A means for giving the position information on the functional element substrate 14 to the obtained image information is the position detection mechanism 38. For this, a length measuring device such as a linear encoder provided in the XY direction scanning mechanism 37 can be used. A position correction control mechanism 39 performs position correction based on the image information and the position information on the functional element substrate 14, and the movement of the XY direction scanning mechanism 37 is corrected by this mechanism. Can be Further, the ejection head 33 is driven by the ejection head control / drive mechanism 40, and the droplet is applied onto the functional element substrate 14. The above-described control mechanisms are centrally controlled by the control computer 35.
[0048]
By the way, FIG. 4 shows a diagram in which droplets are ejected obliquely to the substrate surface. This is because the detection optical system 32 and the ejection head 33 are shown together, and thus the droplets fly obliquely. However, in practice, the spray is applied so as to hit the substrate almost perpendicularly.
[0049]
In the above description, the ejection head unit 11 is fixed, and the relative movement between the ejection head unit 11 and the functional element substrate 14 is performed by moving the functional element substrate 14 to an arbitrary position by the XY direction scanning mechanism 37. However, needless to say, as shown in FIG. 2, the functional element substrate 14 may be fixed and the ejection head unit 11 may scan in the XY directions. In particular, when the present invention is applied to the production of a medium-sized substrate of about 200 mm × 200 mm to a large substrate of 2000 mm × 2000 mm or more, the functional element substrate 14 is fixed as in the latter case, and the X, Y It is preferable that the scanning is performed in the two directions described above, and the application of the solution droplets is sequentially performed in such two orthogonal directions.
[0050]
When the substrate size is about 200 mm × 200 mm or less, the ejection head unit for applying droplets is of a large array multi-nozzle type capable of covering a range of 200 mm, and the relative movement between the ejection head unit and the substrate is orthogonal. It is also possible to perform relative movement only in one direction (for example, only the X direction) without performing in the direction (X direction, Y direction), and mass productivity can be improved, but the substrate size is 200 mm × 200 mm. In the above case, it is difficult to technically and costly to manufacture a large-array multi-nozzle type ejection head unit that can cover such a range of 200 mm. Scanning is performed in two orthogonal directions, X and Y, and the application of liquid droplets is sequentially performed in such two orthogonal directions. It is better to adopt a configuration in which
[0051]
Particularly, as a final substrate, even when a substrate smaller than 200 mm × 200 mm is manufactured, when a plurality of large substrates are to be manufactured, the original substrate is 400 mm × 400 mm to 2000 mm. Since a size of × 2000 mm or more is used, the ejection head unit 11 is made to scan in two orthogonal X and Y directions, and the application of the solution droplets is sequentially performed in such two orthogonal directions. It is better to adopt a configuration in which it is performed.
[0052]
As a material of the droplet 43, a solution containing fine conductive fine particles is used. For example, Au, Pt, Ag, Cu, Ni, Cr, Rh, Pd, Zn, Co, Mo, Ru, W, Os A solution containing fine metal particles such as, Ir, Fe, Mn, Ge, Sn, Ga, and In is preferably used.
In particular, when metal fine particles such as Au, Ag, and Cu are used, a fine circuit pattern having low electric resistance and high corrosion resistance can be formed.
[0053]
In the present invention, the solution containing such fine conductive fine particles includes an aqueous solution and an oil solution.
An aqueous solution obtained by dispersing such fine conductive fine particles in a dispersion medium mainly composed of water can be prepared, for example, by the following method.
[0054]
That is, a water-soluble polymer is dissolved in an aqueous solution of a metal ion source such as chloroauric acid or silver nitrate, and an alkanolamine such as dimethylaminoethanol is added with stirring. The metal ions are reduced in several tens of seconds to several minutes, and fine metal particles having an average particle size of 0.5 μm (500 nm) or less are precipitated. After removing chlorine ions and nitrate ions by a method such as ultrafiltration, the solution is concentrated and dried to obtain a solution containing concentrated conductive fine particles. The solution containing conductive fine particles can be stably dissolved and mixed in water, an alcohol-based solvent, or a binder for a sol-gel process such as tetraethoxysilane or triethoxysilane.
[0055]
An oil-based solution obtained by dispersing fine conductive fine particles in a dispersion medium mainly composed of oil can be prepared, for example, by the following method.
That is, an oil-soluble polymer is dissolved in a water-miscible organic solvent such as acetone, and this solution is mixed with an aqueous metal ion source solution. The mixture is a heterogeneous system, but when alkanolamine is added while stirring the mixture, the metal fine particles are precipitated on the oil phase side in a form dispersed in the polymer. When this is concentrated and dried, a concentrated conductive fine particle-containing solution similar to that of an aqueous system is obtained. The solution containing the conductive fine particles can be stably dissolved and mixed in an aromatic, ketone, ester or other solvent, polyester, epoxy resin, acrylic resin, polyurethane resin or the like.
The concentration of the conductive fine particles in the dispersion medium of the conductive fine particle-containing solution can be up to 80% by weight, but it is appropriately diluted according to the intended use.
[0056]
Usually, the content of the conductive fine particles in the conductive fine particle-containing solution is suitably 2 to 50% by weight, the content of the surfactant and the resin is 0.3 to 30% by weight, and the viscosity is suitably 3 to 30 centipoise.
In any of the materials, the present invention volatilizes volatile components in a solution and leaves a solid content on a substrate to form a pattern wiring or a functional device. The solids generate the function of each pattern or device, and the solvent (volatile component) is a vehicle for ejecting and applying droplets by the ink jet principle.
[0057]
Other examples of the material of the droplet 43 include an I-VII compound semiconductor such as CuCl, a II-VI compound semiconductor such as CdS and CdSe, a III-V compound semiconductor such as InAs, and a IV semiconductor. Semiconductor crystal, TiO ₂ , SiO, SiO ₂ And a solution containing nanoparticles such as a metal oxide such as a phosphor, an inorganic compound such as a fullerene and a dendrimer, an organic compound such as a phthalocyanine and an azo compound, or a composite material thereof.
[0058]
Nanoparticles targeted in the present invention are usually fine particles having a particle size of 0.0005 to 0.2 μm (0.5 to 200 nm), preferably 0.0005 to 0.05 μm (0.5 to 50 nm). More specifically, it is determined in consideration of the dispersion stability of fine particles in the production of a solution, the occurrence of clogging at the time of injection described later, and the surface roughness of a substrate on which a pattern is formed.
[0059]
Incidentally, within the range not impairing the object of the present invention, the surface of these nanoparticles may be chemically or physically modified, or an additive such as a surfactant, a dispersion stabilizer or an antioxidant may be added. good. Such nanoparticles are obtained by a colloid chemistry method, for example, a reverse micelle method (Lianos, P. et al., Chem. Phys. Lett., 125, 299 (1986)) or a hot soap method (Peng, X. et al.). , J. Am. Chem. Soc., 119, 7019 (1997)).
[0060]
The nanoparticle-containing solution that can be suitably used in the present invention is a dispersion in which the above-mentioned nanoparticles are dispersed in an emulsion in which the continuous phase is an aqueous phase and the dispersed phase is an oil phase (O / W emulsion).
[0061]
The aqueous phase is mainly composed of water, but may be used by adding a water-soluble organic solvent to water. Examples of the water-soluble organic solvent include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200, # 400), glycerin, alkyl ethers of the above glycols, N-methylpyrrolidone, 1,3- Dimethylimidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethylsulfoxide, diethanolamine, triethanolamine, ethanol, isopropanol and the like. The amount of the water-soluble organic solvent used in the aqueous dispersion medium is usually preferably 30% by weight or less, and more preferably 20% by weight.
[0062]
The content of the nanoparticles in the dispersion depends on the desired film (layer) structure or particle arrangement structure and the film (layer) thickness, but is usually in the range of 0.01 to 15% by weight based on the total weight of the dispersion. Although it is used, it is more preferably in the range of 0.05 to 10% by weight. If the content of the nanoparticles is too small, there is a possibility that the device function cannot be sufficiently exhibited, and if it is too large, the ejection stability at the time of ejecting the droplet by the ink jet principle is impaired.
[0063]
In the nanoparticle-containing solution that is suitably used in the present invention and is sprayed by the ink jet principle, it is preferable that a surfactant and a solvent for dispersing the nanoparticles coexist in the dispersion. Examples of the surfactant include anionic surfactants (sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, sodium laurate, ammonium salts of polyoxyethylene alkyl ether sulfate, etc.), and nonionic surfactants (polyoxyethylene alkyl Ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, etc., and these may be used alone or in combination of two or more. be able to.
[0064]
The amount of the surfactant is usually used in the range of 0.1 to 30% by weight based on the total weight of the solution, but is more preferably in the range of 5 to 20% by weight. If the amount of the surfactant is less than this range, oil-water separation occurs in the aqueous dispersion, and a uniform pattern of coating may not be obtained by applying droplets. Conversely, if it is more than this range, the viscosity of the aqueous dispersion medium tends to be too high.
[0065]
The solvent for dispersing the nanoparticles is usually a liquid such as toluene, hexane, pyridine, or chloroform, and is preferably volatile. The amount of the dispersing solvent is usually used in the range of about 0.1 to 20% by weight, and more preferably in the range of 1 to 10% by weight. If the amount of the dispersing solvent is too small, the amount of ultrafine particles that can be contained in the aqueous medium will be small. Conversely, if it is more than this range, oil-water separation may occur in the aqueous dispersion medium.
[0066]
Further, the organic compound can be dissolved in the dispersion. Examples of such organic compounds include trioctylphosphine oxide (TOPO), thiophenol, photochromic compounds (spiropyran, fulgide, etc.), charge transfer complexes, electron-accepting compounds, etc., and those which are solid at room temperature are preferred. . In this case, the amount of the organic compound in the dispersion is 1 / 10,000 or more, preferably about 1/1000 to 10 times the weight of the nanoparticles.
[0067]
Incidentally, within the range not impairing the object of the present invention, it is also possible to add an additive such as a surfactant, a dispersion stabilizer or an antioxidant to the suspension, or a polymer, or a binder such as a material which gels in a coating / drying process. good.
[0068]
Droplets of such a nanoparticle-containing solution are applied onto a substrate by the ink jet principle and dried to form a pattern wiring or a functional device. In the present invention, for example, first, at atmospheric pressure, air drying at -20 to 200 ° C., preferably about 0 to 100 ° C. for 1 hour or more, preferably 3 hours or more, and then drying under reduced pressure if necessary. good. The degree of pressure reduction at this time is 1 × 10 ⁵ Pa or less, preferably 1 × 10 ⁴ It is about Pa or lower, and the temperature is usually −20 to 200 ° C., preferably 0 to 100 ° C. The decompression time is about 1 to 24 hours.
[0069]
Although the thickness of the nanoparticle thin film obtained by the above method is not particularly limited, it is generally about 1 mm in diameter of the nanoparticle, preferably about 100 μm in diameter of the nanoparticle. Further, it is preferable that the nanoparticles exist at a certain density or higher in the nanoparticle thin film. In that sense, the average interparticle distance between the individual nanoparticles in the aggregate of nanoparticles is usually within the range of 10 times the particle diameter, and more preferably within the range of 2 times the particle diameter. If the average interparticle distance is too large, the nanoparticles will not exhibit collective function.
[0070]
Next, a liquid jet head suitably applied to the present invention will be described with reference to FIGS. This example is an example of seven nozzles.
This liquid jet head is provided with a piezo element 46 as an energy action section in a flow path 45 into which a solution 47 is introduced. When a pulse-like signal voltage is applied to the piezo element 46 to distort the piezo element 46 as shown in FIG. 5A, the volume of the flow path 45 is reduced and a pressure wave is generated. A droplet 43 is ejected from 48. FIG. 5B shows a state where the distortion of the piezo element 46 is eliminated and the volume of the flow channel 45 is increased.
[0071]
Here, the solution 47 introduced into the flow channel 45 immediately before the nozzle 48 has passed through the filter 49. As described above, in the present invention, the filter 49 is provided in the ejection head, and a filter removing function is provided near the nozzle 48. By doing so, foreign particles larger than those other than the conductive fine particles or nanoparticles in the solution of the present invention are trapped, and the performance of the pattern or device formed on the substrate is not reduced. . Such a filter 49 can be incorporated in the ejection head 11 as shown in FIG. 6 by using a small-sized simple filter. In addition, the ejection head 11 itself can be made compact.
[0072]
As such a filter 49, for example, a stainless mesh filter is suitably used, and the pore size (filter mesh size) is set to 0.8 μm to 2 μm.
[0073]
Next, another example of the liquid jet head suitably applied to the present invention will be described with reference to FIG. This example is an example of a thermal type (bubble type) liquid jet head, and the driving force of the droplet jetting is a growth force of film boiling bubbles generated instantaneously in a solution.
[0074]
The liquid ejecting head shown here is of a type in which droplets are ejected from a short portion of a flow path through which a solution flows, and is called an edge shooter type.
Here, an example is shown in which the number of nozzles of the liquid ejecting head is four. This liquid ejecting head is formed by joining a heating element substrate 66 and a lid substrate 67. The heating element substrate 66 is formed on a silicon substrate 68 by an individual electrode 69, a common electrode 70, and an energy action section by a wafer process. Is formed by forming the heat generating element 71.
[0075]
On the other hand, the lid substrate 67 has a groove 74 for forming a flow channel into which a solution containing a functional material is introduced, and a concave portion for forming a common liquid chamber for accommodating the solution to be introduced into the flow channel. An area 75 is formed, and the flow path and the common liquid chamber are formed by joining the heating element substrate 66 and the lid substrate 67 as shown in FIG. In a state where the heating element substrate 66 and the lid substrate 67 are joined, the heating element 71 is located at the bottom of the flow path, and the solution introduced into these flow paths is located at the end of the flow path. The nozzle 65 for discharging a part of the liquid as droplets is formed. Here, the nozzle shape is rectangular, but this may be round.
[0076]
Further, in consideration of the ejection stability, a nozzle plate may be separately provided on the end face (the area of the nozzle 65) to have a desired nozzle diameter and nozzle shape (for example, a round shape). In this case, for example, Ni is used as the nozzle plate, and a high-precision object can be formed by a method such as electroforming. Alternatively, it is also a good method to use a resin film (substrate) in which nozzle holes are formed by excimer laser processing.
The lid substrate 67 is provided with a solution inlet 76 for supplying a solution into the supply liquid chamber by a supply means (not shown).
[0077]
In the present invention, one functional element is formed by a plurality of droplets, or a pattern forming a functional element or the like is formed by a plurality of droplets by overlapping or contacting dots. Therefore, when such a multi-nozzle type liquid ejecting head is used, a functional element can be formed very efficiently. In this example, the liquid ejecting head has four nozzles. However, the number of nozzles is not necessarily limited to four, and it goes without saying that the larger the number of nozzles, the more efficient the formation of the functional element. However, this does not mean that simply increasing the number of liquid jet heads increases the cost of the liquid ejecting head and increases the probability of clogging of the ejecting nozzles. The balance is determined in consideration of the production efficiency of the conductive element.
[0078]
FIG. 8 shows a view of the multi-nozzle type liquid ejecting head manufactured in this way as viewed from the nozzle side. In the present invention, such a multi-nozzle type liquid ejecting head is provided for each solution to be ejected and mounted on a carriage as shown in FIG. FIG. 10 is a perspective view thereof.
[0079]
9 and 10, the multi-nozzle type liquid ejecting heads are denoted by A, B, C and D, respectively. A different type of conductive fine particle-containing solution or nanoparticle-containing solution can be ejected for each liquid ejecting head while being separated from each other.
[0080]
The present invention is to produce a functional device by spraying a solution containing conductive fine particles or a solution containing nanoparticles, but not only to spray a single solution, but also Since various types of solutions can be sprayed, for example, a device structure combining a solution for forming an electrode pattern and a solution for forming a functional device can be easily formed.
[0081]
Next, other features of the present invention will be described. As described above, in the present invention, a pattern wiring is formed or a functional device is formed. The solution used for the formation is a nanoparticle-containing solution. Then, the present invention relates to a technique for forming a pattern on a substrate by jetting the solution from a fine discharge port by a technique equivalent to the so-called inkjet jetting principle. However, in the inks conventionally used in the inkjet recording field, the dye is dissolved in the solution, whereas in the solution used in the present invention, the nanoparticles are only dispersed in the solution, so clogging occurs. Cheap.
[0082]
Further, according to the present invention, from the required use of the pattern or the device, a fine orifice diameter which is not conventionally available, for example, the diameter of the orifice is Φ20 μm or less (about 300 μm in area) ² This clogging is a very serious problem, because a jetting head as described below must be used.
[0083]
By the way, clogging is derived from the very principle that a solution is ejected from a fine discharge port. In other words, this is caused because the discharge port is fine. Therefore, there is a close relationship between the size of the discharge port and the size of the nanoparticles, which may be called foreign particles in the solution.
[0084]
In view of this point, the present invention pays attention to the size of the discharge port and the size of the nanoparticles, and finds out the relationship between the difficulty of clogging and the relationship therebetween. Specifically, a solution in which the nanoparticle diameter is changed is prepared, a droplet is ejected for a certain period of time using an ejection head whose ejection port is known, and then left for a certain period of time, and the droplet ejection is restarted. The discharge port was examined for clogging. In this case, not only the complete obstruction of the discharge port, but also partial clogging and the prior signs (slight clogging) leading to it were considered as clogging and tested.
[0085]
The used ejection head uses the piezo element 46 as shown in FIGS. 5 and 6 as a driving force for discharging the droplet. That is, the mechanical displacement of the piezo element 46, which is an electromechanical conversion element, is used as the displacement of the diaphragm of the liquid chamber, and droplets are ejected from fine discharge ports by the displacement acting force.
[0086]
Although not shown in the figure, an ejection head having a structure in which a nozzle plate having a nozzle hole separately provided on one surface of the nozzle was provided. The number of nozzles is shown as a simplified example of seven nozzles in the figure, but the number of nozzles (discharge ports) actually used is 64 and the arrangement density is 100 dpi. The driving voltage for droplet ejection was 20 V, and the driving frequency was 10 kHz. In addition, ejection heads H1 to H4 were prepared (the discharge port diameters were H1 = Φ20 μm, H2 = Φ15 μm, H3 = Φ10 μm, and H4 = Φ5 μm). The nozzle plate was formed by Ni electroforming, and the thickness of the discharge port portion was 25 μm.
[0087]
The solution used was produced as follows. That is, a water-soluble polymer was dissolved in silver nitrate, dimethylaminoethanol was added with stirring, and metal ions were reduced in 3 minutes to precipitate Ag fine particles having an average particle size of 0.5 μm (500 nm) or less. Thereafter, chlorine ions and nitrate ions were removed by an ultrafiltration membrane, and concentrated and dried to obtain a concentrated Ag fine particle-containing solution.
[0088]
Further, this Ag fine particle-containing solution was dissolved in acetone, and alkanolamine was added with further stirring to precipitate the Ag fine particles in the form of a dispersion in the polymer on the oil phase side. The concentrated Ag fine particle-containing solution which was concentrated and dried was dissolved and mixed in a mixed solvent of water, alcohol and ethylene glycol to obtain a jetting solution. In addition, in order to produce a solution in which the size of the Ag fine particles was changed, a centrifugal separator was used to prepare Ag fine particles having an average particle size of 0.0001 μm to 0.5 μm. However, although those having an average particle diameter of 0.0003 μm or less were tried, they could not be evaluated because they were not stable. The content of Ag fine particles in each solution was 10% by weight, and the resin content in the solutions was 20% by weight. The amount of ethylene glycol added was adjusted, and the viscosity of each solution was unified to 20 centipoise.
[0089]
The test was performed by combining each solution having different Ag particle diameters with H1 to H4 having different ejection opening diameters, continuously performing droplet ejection for 10 minutes, and then allowing to stand for 10 hours in an atmosphere at a temperature of 40 ° C. and a humidity of 30%. Thereafter, the injection was restarted to check the occurrence of clogging. The results are shown in Tables 1 to 4.
[0090]
Table 1 shows the case of the head H1 (discharge port diameter Do = Φ20 μm), Table 2 shows the case of the head H2 (discharge port diameter Do = Φ15 μm), Table 3 shows the case of the head H3 (discharge port diameter Do = Φ10 μm), and Table 4 shows the head H4 (Discharge port diameter Do = Φ5 μm) is shown. In the judgment, a circle indicates a case where it can be practically used satisfactorily, a triangle indicates a case where it can be used but is not so preferable, and a cross indicates a case where it is not practical at all.
[0091]
[Table 1]

[0092]
[Table 2]

[0093]
[Table 3]

[0094]
[Table 4]

[0095]
From the above results, in the case where the ejection head having the ejection diameter of Φ5 μm to Φ20 μm is used, the Ag fine particle diameter Dp and the ejection diameter Do do not clog if the relationship of Dp / Do ≦ 0.01 is satisfied. It can be seen that stable droplet ejection can be obtained. Although the lower limit of Dp / Do is considered, it is difficult to make the Ag fine particle diameter Dp 0.0003 μm or less in consideration of such a very fine fine particle being stably dispersed in a solution. In order to stably eject droplets to all ejection heads having an ejection diameter of 20 μm or less, the lower limit of Dp / Do may be set to 0.0001 with a margin. That is, if the relationship between the diameter Dp of the Ag fine particles and the diameter Do of the discharge port satisfies the relationship of 0.0001 ≦ Dp / Do ≦ 0.01, the pattern by the droplet discharge using the discharge head having the discharge port diameter of Φ20 μm or less can be obtained. It can be seen that a stable dispersion liquid capable of forming or forming a device can be manufactured, and clogging of the discharge port (nozzle) can be prevented.
[0096]
In this experiment, a circular discharge port (nozzle) was used. However, in the case of another shape, the area may be compared. For example, in the case of a rectangular discharge port of 18 μm × 18 μm, the round shape of the present invention is used. Φ20 μm nozzle. In other words, the present invention has an area of approximately 300 μm ² Injection head using the following nozzles, and its lower limit is approximately 20 μm ² The nozzle (having a discharge port diameter of Φ5 μm) is used to spray such a solution to form a pattern or form a device.
[0097]
In the experiment, a jet head using a piezo element as a driving force for discharging liquid droplets was used. However, the problem of clogging caused by the principle of jetting a solution containing fine particles from a fine discharge port is instantaneous in a solution described later. This is a common problem for the ejection head based on the principle that the solution containing fine particles is ejected from the minute discharge port by using the growth action force of the generated film boiling bubbles. It can be applied as it is.
[0098]
In addition, the method of generating film boiling bubbles using a thermal head or the like enables high-density, high-integration arrangement of the heating element portion and the discharge port portion due to its structure, and an arrangement density of 600 dpi to 1200 dpi or more, and The number of discharge ports (nozzles) of 500 to 10000 can be easily realized, which is suitable for a manufacturing apparatus with high production efficiency.
[0099]
Next, other features of the present invention will be described. As described above, in the present invention, the fine particle-containing solution is configured to eject stable droplets without causing clogging from the minute ejection port. The following shows the results of studying how to form a simple pattern or device.
[0100]
As described above, in the present invention, the discharge head unit 11 moves the pattern while keeping a certain distance from the substrate 14 or moving the pattern in the X and Y directions parallel to the formation surface of the functional device group. Alternatively, a functional device group is formed. That is, the ejection head unit 11 moves parallel to the substrate surface with respect to the substrate 14, or the substrate 14 moves parallel to the ejection head unit 11.
[0101]
At this time, a high-precision pattern or a functional device group can be formed by stopping the relative movement each time the fine particle-containing solution for forming the pattern or the functional device group is ejected and performing the ejection. However, since the productivity is significantly reduced, the solution is sequentially sprayed without stopping the relative movement. In this case, the relative moving speed (for example, the moving speed of the carriage 12 in the X direction in FIG. 2) should not be determined merely by improving the productivity, but from the viewpoint of forming a highly accurate pattern or a functional device group. Must also be considered.
[0102]
FIG. 11 shows the shape of the solution at the time of jetting and flying when the fine particle-containing solution is jetted from the fine discharge port using the growth action force of the film boiling bubble which is preferably used in the present invention. . FIG. 12 and FIG. 13 show the shape of the solution at the time of jetting and flying when the piezo element is used as a driving force for droplet ejection and jetted by a mechanical action force.
[0103]
The difference between FIG. 11 and FIGS. 12 and 13 is that, in the case of FIG. 11, a part of the solution is heated to 300 to 400 ° C. instantly (for several μs) to generate film boiling bubbles, and the instantaneous In order to eject the solution using the growth (for several μs) and the pressure rise (acting force), the piezo element is used as the driving force of the droplet discharge, and the ejection pressure is lower than when ejecting by the mechanical acting force. It is high and the injection speed is fast. As a result, as shown in FIG. 11, at the time of flight, the flight shape of the solution is elongated in the direction of flight in the form of an elongated column, and the solution is flying at a high speed with a plurality of fine droplets (satellite fine droplets 81) behind. ing. For example, the shape at the time of the flight of the solution is such that, when a stable film-boiling bubble is normally generated and caused to fly, the length l of the elongated columnar shape extending in the flight direction is at least 5 times the diameter d, and The flying speed is about 5 m / s to 20 m / s.
[0104]
As a result, there is an advantage that the jetting is stable and the jetting accuracy of the jetted solution on the substrate is high.On the other hand, if the relative moving speed of the jetting head and the substrate is not appropriately selected, the jetting solution becomes an elongated column in the flight direction. The extended solution at the rear portion and a plurality of microdroplets (satellite microdroplets 81) connected to the rear portion may prevent good round dot formation.
[0105]
As a result of intensive studies on this point in the present invention, it has been found that, when such a fine particle-containing solution is injected, it is necessary to optimize the relationship between the injection speed and the relative movement speed.
[0106]
By the way, when the ejection head unit 11 is relatively moved in the X and Y directions while keeping the ejection head unit 11 at a fixed distance with respect to the substrate 14 to eject the solution containing fine particles to form a pattern or a functional device group. The solution is attached and formed on the substrate 14 at the speed of the combined vector of the relative speed and the jet speed. With respect to the positional accuracy, the solution is attached to the target position by appropriately selecting the ejection timing in consideration of the distance between the substrate 14 and the solution ejection port surface of the ejection head unit 11 and the speed of the composite vector. be able to.
[0107]
However, even if it is possible to adhere to the target position, if the relative speed is too fast, the attached solution flows on the substrate 14 by being dragged by the relative speed, and a good round dot shape is obtained. In other words, a good pattern or a group of functional devices cannot be formed. In addition, a plurality of minute droplets (satellite minute droplets 81) connected rearward are attached in a randomly scattered state at positions deviating from the positions where they should originally be attached, preventing good round dot formation and preventing functional device performance. May cause a decrease in The present invention has examined this point.
[0108]
The following is an example of the study results. In this example, by using the apparatus as shown in FIG. 2, the moving speed of the carriage 12 in the X direction and the jetting speed of the ejection head unit 11 are changed so that a good solution can be attached on the substrate 14 and a good pattern can be formed. It is checked whether it is.
[0109]
FIG. 14 shows an example of a pattern used for the test. In this case, a solution containing Ag fine particles is sprayed to form a wiring pattern in which two adjacent rows of element electrodes (between the ITO transparent electrodes 82) are connected with dot patterns made of the solution, and the state of formation of the pattern is evaluated. It was done. For evaluation, the pattern after formation was observed under a microscope, and good / bad (不良 / ×) was determined. FIG. 14 (A) is good (○), and as shown in FIG. 14 (B), the individual dot patterns do not have a good round shape, but have an oval shape. Are out of position and come into contact with an adjacent dot pattern are bad (x). Further, those in which minute droplets caused by satellite droplets were scattered were also regarded as defective (x).
[0110]
In addition to the evaluation of such a shape, the resistance value between the upper and lower ITO transparent electrodes was measured, and the disconnection due to poor dot position accuracy or the resistance value fluctuation due to contact with adjacent (left and right) dots were evaluated (（: Resistance value as aimed, ×: resistance value not at target.
[0111]
Details of the experimental conditions are shown below. The substrate used was a glass substrate with an ITO transparent electrode, and the above-mentioned Ag fine particle-containing solution (here, a fine particle having a particle size of 0.01 μm was used) was sprayed with the jet head shown in FIG. A dot pattern 83 as shown in FIG. 14 was formed in combination with a multi-nozzle plate formed by Ni electroforming. FIG. 14 shows a diagram in which the space between the pair of ITO transparent electrodes 82 is formed to be filled with four dots for simplicity. However, in actuality, dots of about Φ8 μm are vertically arranged in one row. Approximately 1000 are implanted at a pitch of about 4 μm to connect the upper and lower ITO transparent electrodes 82 (the distance between the electrodes is 4 mm). Further, with the center-to-center distance being 12 μm, a similar ITO transparent electrode 82 and a similar pattern connecting between the ITO transparent electrodes 82 are formed.
[0112]
The ejection head used was the above-described ejection head (FIG. 7 shows simplified four nozzles), but the number of nozzles (discharge ports) is 64. The array density is 400 dpi. The size of the heating element is 10 μm × 40 μm, and its resistance value is 102Ω. The driving voltage of the head was 11 V, the pulse width was 2 μs, and the driving frequency was 14 kHz. The volume of the ejected droplet is approximately 1 pl.
[0113]
Under such conditions, the above-described pattern (FIG. 14) is formed on a glass substrate, and the formed pattern is evaluated. Under the same conditions, a separate injection experiment is performed to obtain a solution 3 mm away from the discharge port. Was observed. This is because the test pattern of FIG. 14 was manufactured with the distance between the substrate and the discharge port being 3 mm. As shown in FIG. 11, the flight form was a column (1 = 5d to 20d) that was very elongated in the flight direction. Further, the state was such that a plurality of minute droplets (satellite minute droplets 81) were accompanied behind the flying droplet. The results of the study are shown below.
[0114]
[Table 5]

[0115]
From the above results, it can be seen that when the moving speed of the carriage in the X direction exceeds １ ／ of the ejection speed, a good element cannot be formed. This example is an example in which the ejection head is scanned by the carriage, but is also applicable to a case where the ejection head is fixed and the substrate is moved as shown in FIG. That is, the relative movement speed between the ejection head and the substrate must be equal to or less than 1/3 of the speed of the solution to be ejected.
[0116]
Next, still another feature of the present invention will be described. Substrates (including sheets) to which the function of the present invention has been imparted are formed by dispersing a myriad of fine particles and nanoparticles in a solution containing fine particles and nanoparticles in the air based on the principle of inkjet, and forming droplets on the substrate as droplets. It is manufactured by applying, but in order to manufacture a substrate with high precision and high quality function, a nanoparticle-containing solution is sprayed and applied on the substrate to form a fine pattern. In this case, it is necessary to optimize the surface roughness of the substrate and the size of the nanoparticles. For example, the surface roughness of a substrate is irregularities on the surface. When particles having a size protruding from the irregularities adhere to the surface of the substrate as shown in FIG. 15, a good pattern or device is formed. Will not get.
[0117]
On the other hand, as shown in FIG. 16, if the fine particles 85 are particles having a size equal to or less than the irregularities of the substrate surface 86, a good pattern or device will be obtained. In view of this point, in the present invention, a pattern was formed on a substrate whose surface roughness is known in advance by using a solution containing fine particles having different sizes, and the quality of the formed pattern was evaluated.
[0118]
In the experiment, Pyrex (R) glass was polished so that the surface roughness became 0.01 s to 0.02 s, and the above-mentioned Ag fine particle-containing solution (here, the fine particle diameter was 0 μm) was formed on the polished substrate. .0005 μm to 0.2 μm), and a thermal (bubble) liquid injection by the action of growing film boiling bubbles which instantaneously generates the driving force of the droplet injection as shown in FIG. The ink was ejected in combination with a head to form a pattern in which dots were connected, and the smoothness of the pattern was observed under a microscope, and the sensory evaluation was performed to judge good to acceptable to poor (O to Δ to X).
[0119]
Note that, here, an ejection head having a structure in which a nozzle plate having a nozzle hole separately provided on the surface of the nozzle 65 was used instead of a type in which the flow path directly serves as the nozzle 65 as shown in FIG. 7 was used. The nozzle is a round nozzle formed by Ni electroforming, and has a size of Φ5 μm and a thickness of the opening of 10 μm.
[0120]
The number of nozzles was 64 and the array density was 400 dpi. The heating element size is 10 μm × 40 μm, and its resistance value is 100Ω. The drive voltage of the head was 10 V, the pulse width was 2 μs, and the drive frequency was 14 kHz. The amount of one droplet ejected under this condition is about 1 pl.
[0121]
As shown in FIG. 14, the formed pattern is formed by vertically arranging dots of about Φ8 μm at a pitch of about 4 μm in one row vertically between ITO transparent electrodes 82 formed at intervals of 0.4 mm vertically on Pyrex (R) glass. 100 dots have been printed (FIG. 14 shows an example of four dots for simplicity).
[0122]
In order to obtain a dot pitch of 4 μm, the ejection head and the substrate are moved relative to each other (here, the substrate is fixed, the ejection head is scanned by the carriage), the position is controlled in μ order, and the ejection timing is controlled. Dot attachment was performed at a pitch of about 4 μm as described above. Further, with the center-to-center distance being 12 μm, similar ITO transparent electrodes and similar patterns connecting between the ITO transparent electrodes are formed.
[0123]
Under such conditions, the above-described dot pattern (FIG. 14) is formed on the glass substrate, and the pattern evaluation after formation is performed. Under the same conditions, a separate injection experiment is performed, and a 3 mm distance from the discharge port is measured. The spray condition of the solution was observed. This is because the test pattern of FIG. 14 was manufactured with the distance between the substrate and the discharge port being 3 mm. As shown in FIG. 11, the flight form was a column (1 = 5d to 20d) that was very elongated in the flight direction. Further, the state was such that a plurality of minute droplets (satellite minute droplets 81) were accompanied behind the flying droplet.
[0124]
As described above, Ag fine particle-containing solutions having different particle diameters from 0.0005 μm to 0.2 μm were prepared and used (the solution No. is common), but the particle diameter was 0.02 μm or more. In this case, since nozzle clogging began to occur, evaluation was performed by selecting only those patterns which did not cause clogging and were well formed. The results are shown below.
[0125]
[Table 6]

[0126]
From the above results, it can be understood that the fine particles contained in the solution can form a smooth, good and highly accurate pattern when the size of the fine particles is not more than the surface roughness of the surface on which the pattern of the substrate is formed. On the other hand, it is understood that when the size of the fine particles is made larger than that, the smoothness of the pattern shape is impaired.
[0127]
In other words, in order to form a smooth and good pattern, the surface roughness of the surface on which the pattern of the substrate is formed may be larger than the size of the fine particles contained in the solution. However, since the fine particles used in the present invention are very fine nanoparticles, the surface roughness of the substrate is visually a mirror surface, and the substrate needs to be polished with high precision. Alternatively, a SiO 2 ₂ Even when a substrate having a thin film formed thereon is used, even when the thin film is formed (for example, formed by sputtering or the like), the SiO 2 having a smooth surface is formed. ₂ In order to obtain a surface, it is necessary to take time and form the film carefully. That is, the substrate manufacturing cost is high.
[0128]
By the way, considering that the pattern wiring substrate or the functional device substrate of the present invention has a structure in which a pattern is formed on one side of the substrate as described above, only the surface on which the pattern is formed has a smooth surface. It turns out that you should use it. In other words, only the surface roughness of the substrate (the surface on which the pattern is formed) has the above-described surface roughness, and it is sufficient that the rear surface has a rougher surface.
[0129]
In other words, in the present invention, a highly accurate pattern wiring substrate or a functional device substrate can be obtained by using a substrate having a lower surface roughness than the surface on which the pattern of the substrate is formed (front surface). In addition, the manufacturing cost of the substrate can be reduced. For example, the back surface roughness is made one digit larger than the front surface (the surface on which the pattern is formed) (for example, if the front surface is 0.01 s to 0.02 s, the back surface is 0.1 s to 0.2 s). Only) significantly reduces the cost of substrate fabrication. If the surface is further roughened, the cost is substantially sufficient to make the front surface almost a good surface, and the manufacturing cost can be reduced to almost half that of a substrate whose front and rear surfaces are polished with high precision. However, the upper limit of the back surface roughness is not limited to any value, and it is necessary to maintain a certain level of quality as an industrial product. This is discussed below.
[0130]
As described above, the present invention manufactures a pattern wiring substrate or a functional device substrate using the manufacturing apparatus as shown in FIG. 2 (or FIG. 3). There is a problem at the time of manufacture that the substrate cannot be moved in close contact with the substrate holding surface. This problem is very similar to the principle that a block gauge uses the smoothness of its surface to attach two block gauges. In short, the back surface of the substrate and the substrate holding surface in contact therewith are too smooth and difficult to remove.
[0131]
In such a case, the problem can be solved by making the surface roughness of either surface (or both surfaces) rough, but in the present invention, the back surface of the substrate is set to be less than the roughness of the substrate holding surface, The holding surface is made rougher.
For one thing, the pattern wiring board or the functional device board manufactured according to the present invention needs to maintain a certain level of quality as an industrial product in consideration of the subsequent use. That is, by maintaining a certain level of smoothness even on the back surface, it is possible to maintain the quality without variation as an industrial product.
[0132]
The second is that it is better to roughen the back surface of the substrate or the substrate holding surface. The substrate holding table 13 is formed of, for example, SUS304, but it is inevitable that the substrate holding surface is damaged during use and the surface becomes rough. In that case, it is better to roughen this surface without smoothing the surface roughness from the beginning to increase the cost. The surface of the substrate holding surface formed by SUS304 or the like is formed by mechanical cutting, grinding, or shaving according to the surface roughness.
[0133]
For example, the roughness of the substrate holding surface made of SUS304 is set to 0.5 s to 1 s by grinding, the substrate to be used is quartz glass (size 100 mm × 100 mm), and the roughness of the back surface is set to 0.1 s to 0.1 s. In the case of 2 s, the roughness of the substrate holding surface made of SUS304 is set to 2 s to 5 s by cutting, the substrate to be used is a PET film (300 mm × 300 mm), and the back surface has a roughness of 0.5 s to 1 s. In this case, the substrate was removed and replaced smoothly without the substrate sticking to the substrate holding surface. That is, by setting the roughness of the back surface of the substrate to be equal to or less than the roughness of the substrate holding surface, it is possible to avoid a problem at the time of manufacturing that the substrate cannot be moved (removal and replacement work of the substrate becomes difficult). Became.
[0134]
In the case where a plurality of minute suction holes are formed on the substrate holding surface of the substrate holding table 13 and the substrate is held by vacuum suction, the surface on which the suction holes are formed is not limited to the present invention. Is regarded as having a roughened surface roughness.
[0135]
Next, still another feature of the present invention will be described. The substrate provided with the function of the present invention is manufactured by flying a fine particle-containing solution obtained by dispersing a myriad of fine particles and nanoparticles in a solution in the air by the principle of ink jet and applying the solution on the substrate. However, in order to stably manufacture a substrate provided with a high-quality function for a long period of time, the manufacturing apparatus must maintain a stable and constant performance. The most important point here is the long-term performance stability of the ejection head.
[0136]
As described above, the fine particle-containing solution used in the present invention is a solution in which fine particles are dispersed in a liquid, and the fine particles are present as abrasive grains dispersed in the solution. In such a case, there is a problem that the passage of the solution in the ejection head is damaged or worn. Among the passages, in particular, scratches and abrasion at the discharge port (nozzle) are problematic because they affect the solution jetting performance of the solution.
[0137]
By the way, the scratches and wear are generated when two objects collide with each other or rub against each other. Therefore, it is considered that the scratches and the wear can be solved by appropriately selecting the hardness of the objects. Although it is true that the flaw also affects the solution jetting performance of the jet head, it is considered that the extent of the flaw depends on the size of the flaw and the size of the path of the solution. For example, even if there is a scratch on the nanometer order in a hose for water discharge having an inner diameter of Φ15 mm to Φ20 mm, it cannot have a great effect on the flow rate of water discharge.
[0138]
In the present invention, in consideration of these points, the hardness of the material of the discharge port, the hardness of the material of the fine particles, and the size of the discharge port are intensively studied.
The ejection head used is an example of a thermal (bubble) liquid ejection head as shown in FIG. 7, and the driving force of the droplet ejection is based on the growth acting force of the film boiling bubbles generated instantaneously in the solution. Things.
[0139]
In FIG. 7, the flow path is a type in which the nozzle 66 is used as it is, but the one used here uses an ejection head having a structure in which a nozzle plate in which a nozzle hole is separately formed on the surface of the nozzle 66 is provided. ing. The nozzle shape was round, the number of nozzles was 64, and the array density was 400 dpi.
[0140]
By performing the solution ejection for a certain period of time using such an ejection head, it is determined whether or not the ejection port (nozzle hole) is damaged, and the pattern shape (dot pattern) formed due to the deterioration of the solution ejection performance. Of the pattern performance) and whether the pattern performance deteriorated (resistance change) was examined. The pattern used is as shown in FIG. The multi-nozzle plate was prepared by changing the material and the nozzle diameter (here, a round shape). Regarding the pattern performance, the difference between the resistance value of the pattern formed at the beginning of the ejection and the pattern formed after the ejection was performed for a certain period of time was examined.
[0141]
The ejection head has a heating element size of 10 μm × 40 μm and a resistance value of 101Ω. The drive voltage of the head was 10 V, the pulse width was 2 μs, and the drive frequency was 14 kHz. Under these conditions, continuous ejection was carried out for 70 hours, and the ejection port portion after the ejection was observed by SEM to check for any flaws. Discharge diameters of 20 μm, 15 μm, and 10 μm were prepared.
[0142]
As a comparative reference example, one having a discharge opening diameter of Φ36 μm (reference head) was also prepared. In this case, the number of discharge ports is 48, and the arrangement density is 180 dpi. The size of the heating element is 35 μm × 180 μm, and its resistance value is 125Ω. The drive voltage of the ejection head was 28 V, the drive frequency was 3.5 kHz, and continuous ejection was performed for 280 hours.
[0143]
The thickness of the nozzle plate was 30 μm when the discharge port diameter was Φ20 μm or Φ15 μm, 20 μm when the discharge port diameter was Φ10 μm, and 40 μm for the reference head. The velocity of the droplet at the time of ejection was about 11 m / s in each of the ejection heads.
[0144]
The nozzle plate was made of Ni and austenitic stainless steel SUS304. For the Ni material, a multi-nozzle plate was manufactured by an electroforming method. For the SUS304 material, a nozzle hole was formed in a stainless steel foil by electric discharge machining. When the hardness was measured by a Vickers hardness meter, the Vickers hardness Hv was 58 to 63 for the Ni material and 170 to 190 for the SUS304 material.
[0145]
The liquid used is an aqueous solution obtained by dispersing fine particles in a dispersion medium mainly composed of water as described above. The fine particles are of the following seven types (S1 to S7). The element names of the contained fine particles and the Vickers hardness Hv in the bulk state are shown.
[0146]
The Vickers hardness Hv is a value from a metal data book (edited by The Japan Institute of Metals, 3rd revised edition, published by Maruzen). The fine particle content in each solution was about 8%, and the fine particle diameter was 0.01 μm to 0.02 μm.
[0147]
[Table 7]

[0148]
The results of evaluation using these sample solutions and jet heads are shown below. In the table, ○ indicates that no noticeable scratch was observed after 70 hours of injection, and X indicates that a large number of scratches were present which could affect the nozzle shape or dimensions. In the pattern shape, “○” indicates that the dot pattern was formed in a favorable round shape at a target position (between a pair of electrodes) when the pattern was formed after the injection for 70 hours (FIG. 14A). Indicates that the position is slightly out of the target position, the shape is irregular, or the minute droplet is scattered around (FIG. 14B). × of the pattern performance is the difference between the resistance value of the pattern formed at the beginning of the ejection and the pattern formed after performing the ejection for a certain period of time. The pattern was almost the same as the pattern formed on the substrate (practical level), and x indicates that the pattern had an abnormally large resistance value or a short circuit (impractical level) when the pattern was formed after the injection for 70 hours. is there. The injection time for the reference head is 280 hours. The results are shown below.
[0149]
[Table 8]

[0150]
[Table 9]

[0151]
[Table 10]

[0152]
[Table 11]

[0153]
From the above results, it can be seen that when the hardness of the contained fine particles is larger than the material of the discharge port (S3, S6), the discharge port is damaged. Also, it can be seen that the pattern shape formed thereby is poor and the pattern performance is also poor. Therefore, it is understood that when such a pattern is formed by the manufacturing apparatus as in the present invention, it is necessary to select a material for the fine particles that is softer than the member constituting the discharge port.
[0154]
Regarding the flaw, there is a case in which the pattern shape does not deteriorate depending on the size of the discharge port. Like the reference head, the discharge port diameter is as large as Φ36 μm (= the area is about 1000 μm). ² In such a case, since the diameter of the discharge port is large even if it is flawed, the flaw is not flawed enough to deteriorate the jetting performance, and a sufficiently usable pattern shape is obtained. On the other hand, the discharge port diameter is Φ20 μm or less (= the area is about 300 μm ² In the case where the area is less than 1/3 of the reference head as in the case of (1), even if the surface is similarly scratched, the influence on the comparison with the discharge aperture is large, and a good pattern shape is obtained. It can be seen that pattern performance cannot be obtained.
[0155]
In other words, if a not so fine pattern is formed, the problem of scratches does not affect the pattern performance, so it does not matter, but as in the present invention, the droplet ejecting head having a discharge port diameter of Φ20 μm or less, In the case where a solution containing fine particles having a fine particle diameter of 0.0005 μm to 0.2 μm is applied by spraying and pattern formation is performed, the flaw of the discharge port portion is fatal to the pattern performance, It is necessary to select a combination of a solution and a discharge port member that does not cause scratches. That is, the fine particles need to be made of a material softer than the member constituting the discharge port.
[0156]
In the experiment, a circular Φ20 μm nozzle (having an area of about 314 μm ² ), Φ15μm nozzle (area is about 177μm ² ), Φ10μm nozzle (area is about 79μm ² ) Was used, but when using a nozzle having another shape (for example, a rectangular shape) as the nozzle of the ejection head, the area may be compared. For example, the 18 μm × 18 μm nozzle may be replaced with the round shape of the present invention. Φ20 μm nozzle. In other words, the present invention has an area of about 300 μm. ² The present invention is applied to a case where a pattern is formed by ejecting such a solution with an ejection head using the following nozzles.
[0157]
Next, still another feature of the present invention will be described. The present invention is a technology for manufacturing a patterned wiring substrate or a device substrate, and a pattern to be formed is a round shape formed on a substrate by spraying the same amount of the fine particle-containing solution flying in the air every time. A dot pattern is formed, and a pattern is formed by combining the dot patterns.
[0158]
The ejection head applied to the present invention can change the size of the droplet or the mass of the flying liquid by changing the input energy to the heating element. However, in the present invention, an unprecedented fine nozzle having a discharge opening diameter of Φ20 μm or less is used, and the amount of the solution to be jetted is very small. Therefore, in principle, although the injection amount can be changed, it is not advisable to perform complicated control of changing the injection amount in order to perform stable repetitive injection, so a solution with the same uniform mass is always used. Is to be injected. That is, the input energy to the heating element of the ejection head is always constant, and the solution having the same mass is repeatedly and stably ejected. As a result, as described above, the round dot pattern formed on the substrate is also good as long as the shape at the time of solution flight is optimized or the ejection speed or the relative movement speed between the ejection head and the substrate is appropriately selected. It is formed as a round dot pattern.
[0159]
By the way, when a pattern of a pattern wiring board or a device substrate is formed by combining such round dot patterns, not only a good round dot pattern, but also a pattern wiring board or a device substrate functions as an electric circuit or an electronic device. The pattern formed by combining them also needs to have a good shape.
[0160]
This will be described with reference to FIG. FIG. 17 shows a case in which a solution containing fine particles is sprayed between two ITO transparent electrodes 82 formed on a substrate to form a round dot pattern 83 to form a patterned wiring substrate or a device substrate. FIG. In the drawing, Ld is the dot diameter when a dot is formed alone on the substrate, and Pd is the distance between the centers of adjacent dots (dot pitch).
[0161]
FIG. 17A shows a case where a dot pattern 83 of three dots is formed between two ITO transparent electrodes, but the formation (implantation) density is too high to electrically connect the two ITO transparent electrodes 82. This is not the case (Pd> Ld). In this case, it does not function as a pattern wiring board or a device board. FIG. 17B shows an example in which each dot is barely electrically connected in the peripheral portion (Pd = Ld). FIG. 17C shows an example in which the dots overlap each other at the peripheral portion and are electrically connected to each other (Pd <Ld) as compared with the case of FIG. 17B. FIGS. 17D and 17E show the case where the area where the dots overlap further is large.
[0162]
Here, from the viewpoint of simply obtaining whether or not electrical connection can be obtained, FIG. 17A is out of the question, and in the case of FIGS. Connected. However, in the case of FIG. 17 (B) and FIG. 17 (C), round dots are combined in one horizontal row. When viewed as one line pattern formed by the dot patterns 83, the line pattern width (width in the vertical direction in the figure) becomes narrow between adjacent dots (the area where the dots 83 overlap), and the risk of disconnection is very large. high. For example, in the case where the dots are barely connected in the peripheral portion as shown in FIG. 17B, the dots are electrically connected for the time being, but they are disconnected at the same time as the input of the electric signal, so that they cannot be used at all. Also in the case of FIG. 17C, for the same reason, even if it can be used at the beginning of use, it cannot withstand long-term use.
[0163]
In the present invention, in order to solve the above problem, one or more dots are surely overlapped between adjacent dots. Even if each dot is barely connected at the peripheral portion as in the case of FIG. 17B, if one dot is formed by overlapping one dot at the center between adjacent dots, there is no one dot. Since one dot is superimposed on the area where the line pattern width has the minimum value, the line pattern width in that area has the maximum value, that is, the width of one dot (Ld).
[0164]
In other words, the condition for forming one dot at the center between adjacent dots is, if expressed differently, assuming that the dot diameter when a single dot is formed is Ld, the density is Ld / 2 or less. It is formed by.
[0165]
In addition, in this case, not only can a line pattern having excellent long-term reliability without disconnection be formed, but also the contour of the line pattern can be smooth with little unevenness. This is the case where only round dots are formed at a density at which electrical connection can be obtained as in FIGS. 17B and 17C, and there are no dots for filling spaces between adjacent dots. 17 (D) and 17 (E), in addition to the density at which an electrical connection can be already obtained, the case where one or more dots for filling the space between adjacent dots are overlapped is provided. It is obvious. In the latter case, the contour of the line pattern is smoother with less unevenness, and an excellent pattern wiring board or device board with less variation can be obtained.
[0166]
In the present invention, as shown in FIG. 17, the final line pattern forms the thinnest pattern that can be formed by the manufacturing apparatus of the present invention, such as forming dots of liquid droplets in one row. It applies to the case.
[0167]
For example, a line pattern as shown in FIG. 18 is also formed by the manufacturing apparatus of the present invention. In this case, three dots arranged in one row in the horizontal direction are arranged to obtain a relatively thick line width. In this example, all three thick line patterns are obtained in the arrangement example of FIG. 17C. That is, this is an example in which disconnection occurs with only one wire.
[0168]
However, since three dots (or two dots) are arranged in this way, they function well without disconnection. Therefore, in the case where a plurality of dots (three in this example) are arranged in this manner, only round dots are formed at a density at which an electrical connection can be obtained. Even if there is no dot, there is no danger of disconnection because a plurality of dots are arranged in the vertical direction (line pattern width direction).
[0169]
That is, as in the present invention, the condition that one or more dots for filling the space between adjacent dots are provided so as to be overlapped is the case where droplet dots are arranged in a line to form a fine pattern. This is the condition that must be applied.
[0170]
As is clear from the above description, the present invention is a technology for manufacturing a pattern wiring substrate or a device substrate, but not using a very fine pattern of several tens μm to several μm by a photolithography technology as in the related art. Patterns and devices are directly manufactured by a simple device in which droplets of a solution containing fine particles are directly applied to a substrate by an ejection head having a minute ejection port which has not been conventionally provided. Therefore, expensive manufacturing equipment used in a so-called semiconductor manufacturing process is not required, and the semiconductor device can be manufactured stably at low cost.
[0171]
【The invention's effect】
By jetting a solution containing fine particles by a jet head having a discharge port diameter of 20 μm or less, in a solution jet manufacturing apparatus for manufacturing a pattern wiring substrate or a device substrate, by optimizing the relationship between the surface roughness of the substrate and the size of the fine particles, High precision pattern formation was realized. In addition to optimizing the size and ejection diameter of the fine particles to realize stable ejection without clogging, eject and form a solution that is easy to form good dots, furthermore, the ejection speed of the solution and the substrate By optimizing the relationship with the relative moving speed with the ejection head and optimizing the ejection port material and the hardness of the fine particles used, it is possible to produce high-precision and high-quality pattern wiring boards or device substrates using a new method at low cost. And it can be manufactured stably. Furthermore, since the dots of the solution are formed with the same amount of solution and the implantation density has been optimized, even in the case of a fine pattern in which the dots are arranged in one line, excellent quality and excellent long-term reliability of performance are achieved. You can now get patterns.
[0172]
Further, in a solution jet manufacturing apparatus for manufacturing a pattern wiring substrate or a device substrate by jetting a solution containing fine particles by a jet head having a discharge diameter of 20 μm or less, the relationship between the surface roughness of the substrate and the size of the fine particles is optimized. As a result, highly accurate pattern formation was realized. In addition to optimizing the size and ejection diameter of the fine particles to realize stable ejection without clogging, eject and form a solution that is easy to form good dots, furthermore, the ejection speed of the solution and the substrate The relationship between the relative movement speed to the ejection head and the ejection speed have been optimized, and the ejection port material and the hardness of the fine particles used have been optimized. It has become possible to stably manufacture low-cost patterned wiring boards or device substrates at low cost. Furthermore, since the dots of the solution are formed with the same amount of solution and the implantation density has been optimized, even in the case of a fine pattern in which the dots are arranged in one line, excellent quality and excellent long-term reliability of performance are achieved. You can now get patterns.
[0173]
Further, in the pattern wiring board manufactured by the solution jet manufacturing apparatus as described above, the fine particles in the formed pattern are made of a material softer than a member constituting the discharge port. There is no such thing as wearing or abrasion, which causes deterioration of the jetting performance. In addition, since the relationship between the fine particles and the surface roughness of the substrate was optimized, high-precision pattern formation was realized. Furthermore, because the dots of the solution are formed with the same amount of solution and the arrangement density is optimized, even if it is a fine pattern in which the dots are arranged in one line, a pattern with good quality and excellent long-term reliability of performance Can be obtained.
[0174]
Further, in the pattern wiring board manufactured by the solution jet manufacturing apparatus as described above, the fine particles in the formed pattern are made of a material softer than a member constituting the discharge port. There is no such thing as wearing or abrasion, which causes deterioration of the jetting performance. In addition, since the relationship between the fine particles and the surface roughness of the substrate was optimized, high-precision pattern formation was realized. Further, the surface roughness of the back surface of the substrate is made rougher than the surface roughness of the surface on which the pattern is formed and is equal to or less than the roughness of the holding surface holding the substrate of the solution jet manufacturing apparatus, so that the cost can be reduced when manufacturing the substrate and the manufacturing apparatus. It was realized. Also, since the roughness of the holding surface holding the substrate is larger than the surface roughness of the back surface, when manufacturing such a pattern wiring board, the back surface of the substrate is moved in close contact with the substrate holding surface of the manufacturing apparatus. The problem at the time of manufacturing that no longer can be performed does not occur, and the manufacturing can be performed with a very high yield. Furthermore, since the size of the fine particles and the diameter of the discharge port have been optimized, it can be manufactured by stable jetting without clogging, and high-precision pattern formation has been realized. In addition, since the dots of the solution are formed with the same amount of the solution and the arrangement density is optimized, even a fine pattern in which the dots are arranged in one line has excellent quality and excellent long-term reliability of performance. You can now get patterns.
[0175]
Further, in the device substrate manufactured by the solution jet manufacturing apparatus as described above, since the fine particles in the formed pattern are made of a material softer than the member constituting the discharge port, the discharge port of the jet head may be damaged. , And no deterioration of the injection performance caused by wear. In addition, since the relationship between the fine particles and the surface roughness of the substrate was optimized, a highly accurate device substrate could be realized. Furthermore, because the dots of the solution are formed with the same amount of solution and the arrangement density is optimized, even if it is a fine pattern in which the dots are arranged in one line, a pattern with good quality and excellent long-term reliability of performance Device substrate can be obtained.
[0176]
Further, in the device substrate manufactured by the solution jet manufacturing apparatus as described above, since the fine particles in the formed pattern are made of a material softer than the member constituting the discharge port, the discharge port of the jet head may be damaged. , And no deterioration of the injection performance caused by wear. In addition, since the relationship between the fine particles and the surface roughness of the substrate was optimized, a highly accurate device substrate could be realized. Further, the surface roughness of the back surface of the substrate is made larger than the surface roughness of the surface on which the pattern of the device is formed and is equal to or less than the roughness of the holding surface for holding the substrate of the solution jet manufacturing apparatus, thereby reducing the cost for manufacturing the substrate and the manufacturing apparatus. Was realized. Also, since the roughness of the holding surface holding the substrate is larger than the surface roughness of the back surface, when manufacturing such a device substrate, the back surface of the substrate may be moved in close contact with the substrate holding surface of the manufacturing apparatus. The problem at the time of manufacturing that no longer can be performed does not occur, and the manufacturing can be performed with a very high yield. Furthermore, the size of the fine particles and the diameter of the discharge port have been optimized, so that stable production without clogging can be achieved and a highly accurate device substrate has been realized. In addition, since the dots of the solution are formed with the same amount of the solution and the arrangement density is optimized, even a fine pattern in which the dots are arranged in one line has excellent quality and excellent long-term reliability of performance. A device substrate with a pattern can now be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an embodiment of a pattern wiring formed by a solution jet manufacturing apparatus of the present invention.
FIG. 2 is a view for explaining an embodiment of a solution jet manufacturing apparatus for manufacturing a pattern wiring substrate or a device substrate according to the present invention.
FIG. 3 is a view for explaining another embodiment of the solution jet manufacturing apparatus for manufacturing a pattern wiring substrate or a device substrate according to the present invention.
FIG. 4 is a schematic configuration diagram showing a solution applying apparatus applied to the manufacture of a pattern wiring substrate or a device substrate according to the present invention.
FIG. 5 is a diagram illustrating the principle of droplet ejection of an ejection head using a piezo element.
FIG. 6 is a view showing a structure of an ejection head using a piezo element.
FIG. 7 is an example of a thermal (bubble) liquid ejection head suitably applied to the present invention.
FIG. 8 is a view of the multi-nozzle type liquid ejecting head as viewed from the nozzle side.
FIG. 9 is a view in which a multi-nozzle type liquid ejecting head is stacked and unitized for each solution to be ejected.
FIG. 10 is a perspective view of a unitized head.
FIG. 11 is a diagram for explaining an example of a solution flying shape when the ejection head used in the solution ejection manufacturing apparatus of the present invention ejects with the action force of film boiling bubbles.
FIG. 12 is a view for explaining an example of a droplet flying shape in a case where the ejection head used in the solution ejection manufacturing apparatus of the present invention ejects with an acting force due to mechanical displacement.
FIG. 13 is a diagram for explaining another example of a droplet flying shape when the ejection head used in the solution ejection manufacturing apparatus according to the present invention ejects the droplet by an action force due to mechanical displacement.
FIG. 14 is a diagram showing an example of a test pattern used for finding conditions for forming a good pattern by the solution jet manufacturing apparatus of the present invention.
FIG. 15 is a diagram schematically showing a relationship between fine particles and surface roughness when a dot pattern is formed by a solution containing fine particles having a surface roughness larger than that of a substrate.
FIG. 16 is a diagram schematically showing a relationship between fine particles and surface roughness when a dot pattern is formed by a solution containing fine particles having a size equal to or smaller than the surface roughness of the substrate.
FIG. 17 is a diagram illustrating an example in which dots of droplets are arranged in one row to form a fine line pattern.
FIG. 18 is a diagram for describing an example in which a plurality of dot rows of droplets are arranged to form a thick line pattern.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Wiring pattern, 2, 3 ... Terminal, 10 ... Substrate, 11 ... Discharge head unit (ejection head), 12 ... Carriage, 13 ... Substrate holding stand, 14 ... Substrate, 15 ... Supply tube, 16 ... Signal supply cable, 17: injection head control box, 18: X direction scan motor, 19: Y direction scan motor, 20: computer, 21: control box, 22: substrate positioning / holding means, 31: head alignment control mechanism, 32: detection optical system , 33: ejection head, 34: head alignment fine movement mechanism, 35: control computer, 36: image identification mechanism, 37: XY direction scanning mechanism, 38: position detection mechanism, 39: position correction control mechanism, 40: ejection head drive Control mechanism, 41: optical axis, 42: element electrode, 43: droplet, 44: landing position, 45: flow path, 6 Piezo element, 47 solution, 48 nozzle, 49 filter, 65 nozzle, 66 heating element substrate, 67 lid plate, 68 silicon substrate, 69 individual electrode, 70 common electrode, 71 heat generation Body, 74: groove, 75: concave area, 76: solution inlet, 81: satellite microdrop, 82: element electrode (ITO transparent electrode), 83: dot pattern, 84: microdrop, 85: fine particle, 63: substrate surface.

Claims (6)

A fine particle-containing solution is jetted and applied by a jetting head having a discharge port diameter of Φ20 μm or less on the substrate, a pattern is formed on the substrate and the electrode region, and volatile components in the pattern formed by the applied solution are volatilized, In a solution jet manufacturing apparatus for forming a pattern wiring or a device by leaving a solid content on the substrate and the electrode region, the surface of the substrate on which the pattern is formed is made coarser than the size of the fine particles. In addition, when the size of the fine particles is Dp and the discharge port diameter is Do, 0.0001 ≦ Dp / Do ≦ 0.01, and the ejection head is capable of generating the film boiling bubbles instantaneously generated in the solution. The solution is sprayed by the growth action force, and the shape at the time of solution flight is an elongated columnar shape extending in the flight direction, and at least five times its diameter. And the relative movement speed between the substrate and the ejection head is set to 1/3 or less of the ejection speed of the solution, and the discharge port is formed on a substrate made of a material harder than the fine particles in the fine particle-containing solution. A solution jet manufacturing apparatus which is an opening, wherein the pattern formed by the solution jet manufacturing apparatus is formed by arranging dots formed by the solution in a line, and forming dots of the solution by the same solution. A liquid jet manufacturing apparatus characterized in that, when a dot diameter is defined as Ld when the dots are formed singly, the dots are formed by being driven at a density of Ld / 2 or less. A fine particle-containing solution is jetted and applied by a jetting head having a discharge port diameter of Φ20 μm or less on the substrate, a pattern is formed on the substrate and the electrode region, and volatile components in the pattern formed by the applied solution are volatilized, In a solution jet manufacturing apparatus for forming a pattern wiring or a device by leaving a solid content on the substrate and the electrode region, the surface of the substrate on which the pattern is formed is made coarser than the fine particles. In addition, when the size of the fine particles is Dp and the discharge port diameter is Do, 0.0001 ≦ Dp / Do ≦ 0.01, and the ejection head is capable of generating the film boiling bubbles instantaneously generated in the solution. The solution is sprayed by the growth action force, and the shape at the time of solution flight is an elongated columnar shape extending in the flight direction, and at least five times its diameter. And the relative moving speed between the substrate and the jetting head is set to 1/3 or less of the jetting speed of the solution, and the solution at the time of the elongated columnar flight is caused to fly at high speed with a plurality of fine droplets at the rear. Wherein the discharge port is an opening formed in a substrate made of a material harder than the fine particles in the fine particle-containing solution, wherein the pattern formed by the solution jet manufacturing apparatus is When the dots formed in the above are arranged in one line, the dots of the solution are formed with the same amount of solution, and when the dot diameter when the dots are formed alone is Ld, Ld / 2 or less A solution injection manufacturing apparatus characterized by being formed by driving at a density. A fine particle-containing solution was jetted onto the substrate by a jet head having a discharge port diameter of Φ20 μm or less by the growth force of the film boiling bubbles generated instantaneously in the solution, and the shape of the solution during flight increased in the flight direction. It has an elongated columnar shape and has a length of 5 times or more its diameter, and is made to fly at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, thereby forming a pattern wiring or a device. In the patterned wiring substrate provided with the function manufactured by the solution jet manufacturing apparatus to be formed, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern of the patterned wiring substrate is formed. A patterned wiring board having a surface roughness of a surface to be formed coarser than a size of the fine particles, wherein the pattern is formed by the solution. When the dots to be formed are formed in a line, the dots of the solution are formed with the same amount of solution, and when the dot diameter when the dots are formed alone is Ld, the density is Ld / 2 or less. A pattern wiring board characterized by being formed by driving. A fine particle-containing solution was jetted onto the substrate by a jet head having a discharge port diameter of Φ20 μm or less by the growth force of the film boiling bubbles generated instantaneously in the solution, and the shape of the solution during flight increased in the flight direction. It has an elongated columnar shape and has a length of 5 times or more its diameter, and is made to fly at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, thereby forming a pattern wiring or a device. In the patterned wiring substrate provided with the function manufactured by the solution jet manufacturing apparatus to be formed, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern of the patterned wiring substrate is formed. The surface roughness of the surface to be formed is made larger than the size of the fine particles, and the surface roughness of the back surface of the pattern wiring substrate is Surface roughness of the surface to be formed and not more than the roughness of the holding surface for holding the pattern wiring board of the solution jet manufacturing apparatus, and the fine particles in the pattern have a size of Dp and a discharge port diameter of Do. When the pattern wiring board satisfies 0.0001 ≦ Dp / Do ≦ 0.01, and the pattern is formed by arranging dots formed by the solution in one row, Are formed in the same amount of solution, and when the dots are formed independently, the dot diameter is Ld, and the pattern wiring substrate is formed by being driven at a density of Ld / 2 or less. A fine particle-containing solution was jetted onto the substrate by a jet head having a discharge port diameter of Φ20 μm or less by the growth force of the film boiling bubbles generated instantaneously in the solution, and the shape of the solution during flight increased in the flight direction. It has an elongated columnar shape and has a length of 5 times or more its diameter, and is made to fly at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, thereby forming a pattern wiring or a device. In the device substrate provided with a function manufactured by the solution jet manufacturing apparatus to be formed, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern of the device substrate is formed. A device substrate having a surface roughness greater than the size of the fine particles, wherein the pattern is formed by dots formed by the solution. In the case where the dots are formed in one line, the dots of the solution are formed with the same amount of solution, and when the dot diameter when forming the dots alone is Ld, the dots are driven at a density of Ld / 2 or less. A device substrate characterized by being formed. A fine particle-containing solution was jetted onto the substrate by a jet head having a discharge port diameter of Φ20 μm or less by the growth force of the film boiling bubbles generated instantaneously in the solution, and the shape of the solution during flight increased in the flight direction. It has an elongated columnar shape and has a length of 5 times or more its diameter, and is made to fly at a high speed with a plurality of fine droplets behind, spraying, and forming a pattern on the substrate and the electrode region, thereby forming a pattern wiring or a device. In the device substrate provided with a function manufactured by the solution jet manufacturing apparatus to be formed, the fine particles in the pattern are made of a material softer than a member constituting the discharge port, and the pattern of the device substrate is formed. The surface roughness of the surface is larger than the size of the fine particles, and the surface roughness of the back surface of the device substrate is the surface of the surface on which the pattern is formed. When the roughness is set to be less than the roughness and not more than the roughness of the holding surface for holding the device substrate of the solution jetting manufacturing apparatus, and the size of the fine particles in the pattern is Dp and the discharge port diameter is Do, 0.0001 ≦ Dp / Do ≦ 0.01, wherein the pattern is such that when the dots formed by the solution are arranged in a line, the dots of the solution are formed in the same amount of solution. When the dot diameter is Ld when the dots are formed independently, the device substrate is formed by being driven at a density of Ld / 2 or less.

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