JP2004356125A - Liquid drop ejection production apparatus as well as substrate and device to be produced - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high quality and highly accurate pattern wiring board or a device substrate. <P>SOLUTION: A liquid ejector ejects a plurality of liquid drops of a solution containing fine particles toward a substrate 14 by means of an ejection head 11 to form a pattern wiring or a device by evaporating volatile components of the liquid drop. Surface roughness on the patterning surface of the substrate is set rougher than the size of the fine particle. Assuming the size of the fine particle is Dp and the diameter of an ejection opening is Do, following relation is satisfied 0.0001≤Dp/Do≤0.01. The ejection head 11 ejects a liquid drop with an action force by mechanical displacement to make a flying liquid drop substantially round immediately before adhering to the substrate surface, or to elongate the liquid drop in the flying direction within a length of three times of its diameter so that a plurality of micro drops do not follow the flying drop. A stripe pattern where an non-covered region does not exist in the patterned region is thereby formed through combination of dots being formed by the liquid drops. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００９３】
【表２】

【００９４】
【表３】

【００９５】
【表４】

【００９６】
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。
【００９７】
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。
【００９８】
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、本発明の製造装置に使用される噴射ヘッドはこれに限定されることなく、２枚の電極間の静電力を原動力とし、液室の振動板の機械的変位を発生させる静電方式なども、良好に使用できる。これらは、液体に機械的作用力を付与するものであるため、使用する液体が制限を受けることが少ないという利点がある。また、この機械的変位は、アナログ的に変位させることができるので、駆動波形をコントロールすることにより、飛翔滴の形状も丸い形状とすることができる。たとえば後述するが、本発明では、駆動波形を制御し、丸い形状に近い飛翔滴を形成し、良好なドットパターンを得ているが、これについては後述する。
【００９９】
他に液体中に熱により瞬時に膜沸騰気泡を発生させ、その気泡の成長力を溶液吐出の原動力とした方式の噴射ヘッドも使用できる。あるいは連続的に噴射する液滴に電荷を付与し、その電荷量に応じて液滴を偏向させる荷電制御方式（連続流方式）等も使用できる。
なお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熱を利用するため、使用する溶液が熱劣化することがあるので、ある程度使用できる溶液に制限を受ける。
【０１００】
一方で、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。
【０１０１】
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、ここでは液滴噴射後に基板上に液滴が付着し、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。
【０１０２】
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。
【０１０３】
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。
【０１０４】
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、その噴射速度を前記相対移動速度より速くすることが必要であることに気がついた。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、溶液の液滴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、その狙いの位置に液滴を付着させることができる。
【０１０５】
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液滴が基板１４上で流れ、良好な形状でパターン、あるいは機能デバイス群を形成できなくなる。本発明はこの点について検討したものである。以下に検討結果の一例を示す。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上で良好な液滴付着ができ、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。
【０１０６】
図１１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１１（Ａ）は良（○）であり、図１１（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。
【０１０７】
また、これは目詰まりの初期段階や吐出口へのキズ発生等に起因する噴射性能の劣化によって生ずることが多いが、微小滴が周囲に飛散したりするものも不良（×）である。
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）。
【０１０８】
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）を前述のＨ４噴射ヘッド（ノズル径Φ５μｍ）と組み合わせて、図１１のようなパターン８３を形成した。なお、図１１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。
【０１０９】
使用した噴射ヘッドはＨ４噴射ヘッドであり、ノズル（吐出口）の数が６４個で、その配列密度が１００ｄｐｉのものである。噴射ヘッドと基板は相対運動（ここでは、基板固定、噴射ヘッドをキャリッジ走査）を行い、その制御を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、上記のように約４μｍピッチによるドット付着、ならびに１２μｍの中心間距離を維持したパターン形成を行った。
【０１１０】
液滴噴射の駆動電圧は噴射速度を変えるためにピエゾ素子への入力電圧を１４Ｖから２１Ｖまで変化させている。また駆動周波数は１０ｋＨｚとした。なおこのようなピエゾ素子を利用した噴射ヘッドでは、ピエゾ素子への入力電圧を変えて噴射速度が変えられるが、同時に噴射滴の質量も変化するので、駆動波形（引き打ちも含めた立ち上がり波形ならびに立下がり波形）を制御して、噴射滴の体積がいつもほぼ一定（１ｐｌにした）になるようにし、噴射速度のみを変えるようにした。
【０１１１】
また滴飛翔時の滴の形状を、素子形成と同じ条件で別途噴射、観察し、その形状が、基板面に付着する直前（今本発明例では３ｍｍ）にほぼ丸い滴になるように駆動波形を制御して噴射させた（図１２）。なお完全に丸い球状が得られず、飛翔方向に伸びた柱状であっても、駆動波形を制御するだけで容易にその直径の３倍以内の長さにはなる（ｌ≦３ｄ）ようにできた（図１３）。またその際、後述する（図１４）ような飛翔滴後方に複数の微小な滴（サテライト微小滴８１）を伴うことのない駆動条件（駆動波形）を選んだ。以下に結果を示す。
【０１１２】
【表５】

【０１１３】
以上の結果より、キャリッジのＸ方向移動速度が、噴射速度以上であると、良好なパターン形成できず、また、電極間の抵抗値も狙いからはずれたものになることがわかる。言い換えるならば、本発明のように、ピエゾ素子を利用した噴射ヘッドを利用した装置でナノ粒子含有溶液を基板上に液滴付与し、乾燥させてパターン配線形成、あるいは機能デバイス形成を行う場合、噴射ヘッドから噴射される液滴の速度は、キャリッジのＸ方向移動速度より速くしなければならないことがわかる。
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、噴射される液滴の速度は、噴射ヘッドと基板の相対移動速度より速くしなければならないということである。
【０１１４】
さらに付言すると、今回の滴飛翔条件は、前述のように飛翔滴後方に複数の微小な滴（サテライト微小滴８１）を伴う（図１４）ことのない駆動条件（駆動波形）とした。その結果、これら複数の微小な滴が、不必要なところに付着するということが全くなく、大変良好なパターン形成を行うことができた。
また飛翔滴が飛翔方向に伸びた柱状であっても、駆動波形制御により、飛翔滴の長さをその直径の３倍以内の長さになる（ｌ≦３ｄ）ようにした（図１３）ので、形成されたドットも真円に近い形状となり、良好なパターン形成を行うことができた。
【０１１５】
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。
【０１１６】
一方で、図１６のように、こ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。
【０１１７】
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）を前述のＨ４噴射ヘッド（ノズル径Φ５μｍ）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。
【０１１８】
実験条件の詳細を以下に示す。パターンは縦方向に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。
使用した噴射ヘッドはＨ４噴射ヘッドであり、ノズル（吐出口）の数が６４個で、その配列密度が１００ｄｐｉのものである。噴射ヘッドと基板は相対運動（ここでは、基板固定、噴射ヘッドをキャリッジ走査）を行い、その制御を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、上記のように約４μｍピッチによるドット付着を行った。
【０１１９】
液滴噴射の駆動電圧はピエゾ素子への入力電圧を１５Ｖとし、また駆動周波数は１０ｋＨｚとした。噴射滴の体積がいつもほぼ１ｐｌである。また滴飛翔時の滴の形状を、パターン形成と同じ条件で別途噴射、観察し、その形状が、基板面に付着する直前（今本発明例では３ｍｍ）にほぼ丸い滴になるように駆動波形を制御して噴射させた（図１２）。なお完全に丸い球状が得られず、飛翔方向に伸びた柱状であっても、駆動波形を制御するだけで容易にその直径の３倍以内の長さにはなる（ｌ≦３ｄ）ようにできた（図１３）。またその際、図１４のような飛翔滴後方に複数の微小な滴（サテライト微小滴８１）を伴うことのない駆動条件（駆動波形）を選んだ。
【０１２０】
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。
【０１２１】
【表６】

【０１２２】
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、滑らかな良好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。
【０１２３】
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。
【０１２４】
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。
【０１２５】
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。
【０１２６】
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。
【０１２７】
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。
【０１２８】
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。
【０１２９】
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。
【０１３０】
なお、基板保持台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。
【０１３１】
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、基板上あるいは基板上に電極を形成した領域に、微粒子含有溶液の液滴を複数滴噴射付与し、付与後の液滴パターン中の揮発成分を揮発させ、固形分を前記基板上ならびに電極領域上に残留させることによって液滴のドットによるパターンを組み合わせることによってパターン配線あるいはデバイスを形成する技術である。
【０１３２】
ここで、この液滴のドットによるパターンによって、パターン配線あるいはデバイスを形成する領域は、ある面積を持った帯状パターンである（図１７〜図１９）。図１７は２端子９１間を本発明の液滴によるドットパターン９２によって直線的な配線パターンによって接続し、回路パターンを形成する一例である。図中の矢印の方向に伸びた帯状パターンである。
【０１３３】
図１８も同様に２端子９１間を本発明の液滴によるドットパターン９２による配線パターンによって接続し、回路パターンを形成する一例であるが、この場合は、配線パターンを折り曲げて形成した例である。回路設計上、いつも直線上になるとは限らず、この例のように、折り曲げた配線形成する場合もよくある例である。この場合も図中の２本の矢印の方向に伸びた帯状パターンである。
【０１３４】
図１９は、同様に２つの素子電極９３間に本発明の液滴によるドットパターン９２を形成してデバイス形成を行った例である。
これらの例において、本発明では、このような帯状パターンは、パターン配線あるいは電子デバイスとしての機能を果たすため、その領域にピンホール等の非被覆領域がないようにしている。
【０１３５】
図２０によって説明する。図２０は、本発明の帯状パターンの領域を示したものであるが、図中ｌｘ、ｌｙはそれぞれドットパターン９２におけるＸ方向、Ｙ方向（Ｘ、Ｙは互いに直交する２方向）のドットの中心間距離（パターンピッチ）を示している。またｄはドットパターン９２のドットの直径である。
【０１３６】
本発明では、前述のようにこのような帯状パターンの領域において、非被覆領域がないようにするため、直交する２方向の隣接ドットにおいて、そのドット径ｄを、直交する２方向の中心間距離ｌｘあるいはｌｙの√２倍以上となるように、噴射ヘッドのノズル径あるいは液滴形成条件を選んでいる。図２０の例は実際にドット径ｄを、直交する２方向の中心間距離ｌｘあるいはｌｙの√２倍以上となるようにしたものであり、縦（Ｘ方向）、横（Ｙ方向）、斜めとも各ドットパターンは互いに重なりあうようにして形成されるので、非被覆領域が存在しない帯状パターンとなっている。
【０１３７】
図１７〜図１９の例では、図を簡略化するため、ドット径ｄは中心間距離ｌｘあるいはｌｙの√２倍の例を示しており、ちょうど斜め方向の隣接ドットパターン外縁が接触する条件（非被覆領域が存在しない臨界条件）であり、これ以上の密度でドットパターンを形成することにより、非被覆領域が存在しない帯状パターンを形成できる。
【０１３８】
なお、図１７、図１８中に示した矢印は、帯状パターンが伸びている方向を示しているが、これらの矢印及びその矢印と１８０度反対方向は、前述の図２〜図４で説明したＸ方向、Ｙ方向、すなわち矩形基板の各辺の方向、あるいは機能デバイス群のマトリックス配列の方向と平行にすると、位置決め、あるいは各パターン形成を高精度にできる。よって基本的には、この帯状パターンは、前述の図２〜図４で説明したＸ方向、Ｙ方向に平行な方向に伸びたパターンとされるが、パターン配線の設計上の都合上、それらと違った方向の帯状パターンとなったり、あるいは直線的ではなく曲線上の帯状パターンとする場合も、コンピュータ制御によってそのような画像パターン形成情報を、噴射ヘッドに入力することによって実現できる。その際も、言うまでもないが、本発明の帯状パターンは、非被覆領域が存在しないパターンとされる。
【０１３９】
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。
【０１４０】
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、摩耗は溶液の液滴噴射性能に影響を及ぼすため問題となる。
【０１４１】
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液滴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。
【０１４２】
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、前述のＨ１噴射ヘッド〜Ｈ３噴射ヘッドと同じものである。すなわち図５、図６に示したようなピエゾ素子４６を液滴吐出の原動力とし、電気−機械変換素子であるピエゾ素子４６の機械的変位を液室の振動板の変位として、その変位作用力で、微細な吐出口から液滴を噴射するものである。
なお、図には示していないが、ノズル１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。またそのノズル数は６４個であり、配列密度は１００ｄｐｉである。
【０１４３】
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、液滴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。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。
噴射ヘッドの駆動電圧は２０Ｖ、駆動周波数は１０ｋＨｚとし、１００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（Ｈ１噴射ヘッド）、Φ１５μｍ（Ｈ２噴射ヘッド）、Φ１０μｍ（Ｈ３噴射ヘッド）のものを用意した。
【０１４４】
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６０ｄｐｉのものである。噴射ヘッドの駆動電圧は３０Ｖ、駆動周波数は３．８ｋＨｚとし、２６０時間連続噴射を行った。
【０１４５】
ノズルプレートの厚さは、Ｈ１噴射ヘッド、Ｈ２噴射ヘッドは３０μｍとし、Ｈ３噴射ヘッドは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７ｍ／ｓとした。
【０１４６】
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。
【０１４７】
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。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。
【０１４８】
【表７】

【０１４９】
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１００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１００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１１（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１１（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１００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１００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２６０時間である。
【０１５０】
【表８】

【０１５１】
【表９】

【０１５２】
【表１０】

【０１５３】
【表１１】

【０１５４】
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。言い換えるならば本発明においては、吐出口を構成する部材は、微粒子より硬い材料とする必要がある。
【０１５５】
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。
【０１５６】
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。
【０１５７】
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。
【０１５８】
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。
【０１５９】
【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の液滴を複数滴噴射付与し、パターン配線基板あるいはデバイス基板を製造する液滴噴射製造装置において、基板のパターンが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なパターン形成を実現した。また、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て基板の低コスト化を実現した。さらに、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、機械的変位による作用力で液滴を噴射させるようにし、良好なドットを形成しやすい液滴を噴射、形成するようにしたので、良好なドットパターンが形成できるようになった。また、形成するパターンを液滴によって形成されるドットの組み合わせによって、パターンが形成される領域において非被覆領域が存在しない帯状パターンとされるようにしたので、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。
【０１６０】
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の液滴を複数滴噴射付与し、パターン配線基板あるいはデバイス基板を製造する液滴噴射製造装置において、基板のパターンが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なパターン形成を実現した。また、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て基板の低コスト化を実現した。さらに、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、機械的変位による作用力で液滴を噴射させるようにし、かつ飛翔距離も短くし、またその液滴の噴射速度を、基板と噴射ヘッドとの相対移動速度より速くしたので、良好なドットパターンが形成できるようになった。さらに、形成するパターンを液滴によって形成されるドットの組み合わせによって、パターンが形成される領域において非被覆領域が存在しない帯状パターンとされるようにしたので、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。
【０１６１】
また上記のような液滴噴射製造装置において、噴射ヘッドの吐出口を微粒子含有溶液中の微粒子より硬い材質よりなる基板に形成された開口としたので、長期使用しても吐出口においてキズが発生したり、あるいは破損したりしないので、長期にわたって安定して、高品質なパターン配線基板あるいはデバイス基板を製作できるようになった。
【０１６２】
また上記のような液滴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、基板のパターンが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なパターン形成を実現した。また、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て基板の低コスト化を実現した。さらに、形成されるパターンは液滴パターンの組み合わせによって帯状パターンとし、かつパターンが形成される領域において非被覆領域が存在しないようにしたので、高精度かつ高品質な機能を付与されたパターン配線基板が実現した。
【０１６３】
また上記のような液滴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、基板のパターンが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なパターン形成を実現した。また、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て基板の低コスト化を実現した。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、形成されるパターンは液滴パターンの組み合わせによって帯状パターンとし、かつパターンが形成される領域において非被覆領域が存在しないようにしたので、高精度かつ高品質な機能を付与されたパターン配線基板が実現した。
【０１６４】
また上記のような液滴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、パターン中の微粒子は、噴射ヘッドの吐出口を構成する部材よりやわらかい材料としたので、製造装置を長期使用しても吐出口においてキズが発生したり、あるいは破損したりせず、高品質なパターン配線基板が得られるようになった。
【０１６５】
また上記のような液滴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、基板のデバイスが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なデバイスパターン形成を実現した。また、基板の裏面の表面粗さをデバイスが形成される面の表面粗さより粗くして基板の低コスト化を実現した。さらに、形成されるデバイスパターンは液滴のドットパターンの組み合わせによって帯状パターンとし、かつデバイスパターンが形成される領域において非被覆領域が存在しないようにしたので、高精度かつ高品質な機能を付与されたデバイス基板が実現した。
【０１６６】
また上記のような液滴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、基板のデバイスが形成される面の表面粗さを微粒子の大きさより粗くした、言い換えるならば、微粒子の大きさが基板の表面粗さより微細であるので、高精度なデバイスパターン形成を実現した。また、基板の裏面の表面粗さをデバイスが形成される面の表面粗さより粗くして基板の低コスト化を実現した。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パターン形成を実現した。また、形成されるデバイスパターンは液滴のドットパターンの組み合わせによって帯状パターンとし、かつデバイスパターンが形成される領域において非被覆領域が存在しないようにしたので、高精度かつ高品質な機能を付与されたデバイス基板が実現した。
【０１６７】
また上記のような液滴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、デバイスパターン中の微粒子は、噴射ヘッドの吐出口を構成する部材よりやわらかい材料としたので、製造装置を長期使用しても吐出口においてキズが発生したり、あるいは破損したりせず、高品質なデバイス基板が得られるようになった。
【図面の簡単な説明】
【図１】本発明の液滴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液滴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液滴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液滴付与装置を示す概略構成図である。
【図５】本発明に好適に使用される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】本発明に好適に使用される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】このようにユニット化したヘッドの斜視図ある。
【図１１】本発明の液滴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１２】本発明の液滴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】本発明の液滴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】膜沸騰気泡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】本発明の帯状パターンの例を説明するための図である。
【図１８】本発明の帯状パターンの他の例を説明するための図である。
【図１９】本発明のデバイスパターンの例を説明するための図である
【図２０】本発明のドットパターンで非被覆領域を生じないようにするための条件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…微粒子含有溶液の供給チューブ、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、２１…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、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、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…液滴着弾位置、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、８６…基板表面、９１…端子、９２…ドットパターン、９３…素子電極。[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 fine particle-containing material by the ink jet principle, that is, 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.
(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 an insulating substrate by vapor deposition of a conductive metal, a resist is coated on the conductive layer, and a photolithography method is used to expose a circuit pattern, dissolve and remove an unexposed resist, and remove the resist. A method of forming a copper wire pattern by etching a removed portion.
[0006]
However, since these methods have a problem that they are not suitable for forming a fine pattern, for example, Patent Literature 2 describes that a circuit pattern is directly drawn on a substrate using 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, the 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.
[0007]
As described above, various proposals utilizing 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.
[0008]
[Patent Document 1]
JP 2000-126681 A
[Patent Document 2]
JP 2002-134878 A
[Patent Document 3]
JP 2001-319567 A
[0009]
[Non-patent document 1]
Light emitting devices (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]
Super fast 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 droplet jet manufacturing apparatus for manufacturing a high-quality and high-precision pattern wiring substrate or device substrate with high yield. Is to do.
[0011]
Another object of the present invention is to provide a droplet jet manufacturing apparatus having another configuration for manufacturing a high-quality and high-precision pattern wiring substrate or device substrate with high yield.
[0012]
Further, a third object is to ensure reliability of the droplet jet manufacturing apparatus having such a novel configuration in long-term use.
[0013]
A fourth object of the present invention is to provide a pattern wiring board provided with a high-precision and high-quality function manufactured by such a novel configuration of a droplet jet manufacturing apparatus.
[0014]
Still another object of the present invention is to provide a pattern wiring board provided with higher precision and higher quality functions manufactured by such a novel configuration of the droplet jet manufacturing apparatus.
[0015]
A sixth object is to always provide the quality of such a pattern wiring board stably.
[0016]
Further, a seventh object is to provide a device substrate provided with high-precision and high-quality functions manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0017]
An eighth object is to provide a device substrate provided with higher precision and higher quality functions manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0018]
A ninth object is to always provide such a quality of the device substrate stably.
[0019]
[Means for Solving the Problems]
In order to achieve the above object, the present invention firstly sprays a plurality of droplets of a solution containing fine particles on a substrate by an ejection head having a discharge port diameter of Φ20 μm or less, and forms a pattern on the substrate and an electrode region. In a droplet jet manufacturing apparatus for forming a pattern wiring or a device by volatilizing a volatile component in a droplet pattern after application and leaving a solid content on the substrate and the electrode region, the pattern of the substrate The surface roughness of the surface on which the pattern is formed is larger than the size of the fine particles, the surface roughness of the back surface of the substrate is larger than the surface roughness of the surface on which the pattern is formed, and the size of the fine particles is Dp. When the ejection diameter is Do, 0.0001 ≦ Dp / Do ≦ 0.01, and the ejection head ejects the droplet with an acting force due to mechanical displacement. The shape of the droplet during the flight of the droplet should be a substantially round droplet immediately before adhering to the substrate surface, or a column extending in the flight direction and having a length within three times the diameter, and a plurality of droplets behind the flying droplet. A droplet ejection manufacturing apparatus that does not involve minute droplets, wherein the pattern is formed in a band shape in which an uncovered region does not exist in a region where the pattern is formed by a combination of dots formed by the droplets. It was made to be a pattern.
[0020]
Secondly, a plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge opening diameter of Φ20 μm or less to form a pattern on the substrate and the electrode region. In a droplet jet manufacturing apparatus for forming a pattern wiring or a device by volatilizing a volatile component of 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 larger than the size of the fine particles, and the surface roughness of the back surface of the substrate is larger than the surface roughness of the surface on which the pattern is formed, and the size of the fine particles is Dp, and the discharge port diameter is Do. When 0.0001 ≦ Dp / Do ≦ 0.01, the ejection head ejects the droplet by an action force due to mechanical displacement, and when the flight distance is within 3 mm, Both, the droplet is a droplet ejection manufacturing apparatus that ejects at an ejection speed higher than the relative movement speed of the substrate and the ejection head, wherein the pattern is a combination of dots formed by the droplet, In a region where the pattern is formed, a strip-shaped pattern having no uncovered region is provided.
[0021]
Thirdly, in the droplet ejection manufacturing apparatus according to the first or second aspect, 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.
[0022]
Fourth, a plurality of droplets of the solution containing fine particles are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an acting force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region, In a pattern wiring substrate provided with a function manufactured by a droplet jet manufacturing apparatus for forming a pattern wiring or a device, the surface of the pattern wiring substrate on which the pattern is formed has a surface roughness greater than the size of the fine particles. The surface roughness of the back surface of the substrate is made coarser than the surface roughness of the surface on which the pattern is formed, and the pattern is formed in a region where the pattern is formed by a combination of dots formed by the droplets. A band-shaped pattern having no covering area was used.
[0023]
Fifth, a plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an acting force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region. In a pattern wiring substrate provided with a function manufactured by a droplet jet manufacturing apparatus for forming a pattern wiring or a device, the surface of the pattern wiring substrate on which the pattern is formed has a surface roughness greater than the size of the fine particles. The surface roughness of the back surface of the substrate is made larger than the surface roughness of the surface on which the pattern is formed, and the fine particles in the pattern have a size of Dp and a discharge port diameter of Do, which is 0.0001. ≦ Dp / Do ≦ 0.01, and the pattern depends on a combination of dots formed by the droplets. In the region where the pattern is formed, a strip-shaped pattern having no uncovered region is provided.
[0024]
Sixth, in the patterned wiring substrate according to the fourth or fifth aspect, the fine particles in the pattern are made of a material softer than a member constituting the discharge port.
[0025]
Further, seventhly, a plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge opening diameter of Φ20 μm or less by an acting force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region, In a device substrate provided with a function manufactured by a droplet jet manufacturing apparatus that forms a pattern wiring or a device, the surface roughness of the surface of the device substrate on which the device is formed is made larger than the size of the fine particles, The surface roughness of the back surface of the substrate is made rougher than the surface roughness of the surface on which the device is formed, and the pattern of the device is not formed in a region where the pattern is formed by a combination of dots formed by the droplets. A band-shaped pattern having no covering area was used.
[0026]
Eighth, a plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge opening diameter of Φ20 μm or less by an acting force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region, In a device substrate provided with a function manufactured by a droplet jet manufacturing apparatus that forms a pattern wiring or a device, the surface roughness of the surface of the device substrate on which the device is formed is made larger than the size of the fine particles, The surface roughness of the back surface of the substrate is made larger than the surface roughness of the surface on which the device is formed, and the fine particles have a size of Dp and a discharge port diameter of Do, where 0.0001 ≦ Dp / Do ≦ 0.01, and the pattern of the device is formed in a region where the pattern is formed by a combination of dots formed by the droplets. Thus, a band-shaped pattern having no uncovered region was formed.
[0027]
Ninth, in the device substrate according to the seventh or eighth aspect, the fine particles in the pattern are made of a material softer than a member constituting the discharge port.
[0028]
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 the terminals 2 and 3 are formed on such a substrate 10, and the dotted line 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.
[0029]
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 holding table, 14 a substrate such as a wiring substrate or a functional element substrate or a substrate for 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.
[0030]
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 of FIG. 3 differs from the configuration of 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.
[0031]
The droplet applying device (ejection head 33) of the ejection head unit 11 may be any mechanism as long as it is capable of quantitatively ejecting arbitrary droplets, and particularly, an ink jet principle capable of forming droplets of about 0.1 pl to several hundred pl. Mechanism is desirable.
[0032]
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 the electric signal is converted into mechanical vibration of the piezoelectric vibrating element. Are ejected and fly, and are generally called a drop-on-demand system.
[0033]
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.
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. The method is called a thermal ink jet system or a bubble jet (R) system.
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.
[0034]
In the present invention, in a manufacturing apparatus (FIG. 2) for forming such a pattern wiring board or a functional device (functional element), 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.
[0035]
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 connection, the shape of the pattern wiring substrate or the functional device forming substrate of the present invention and the arrangement of the functional device groups to be formed will be described first.
[0036]
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, or 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.
[0037]
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.
[0038]
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.
[0039]
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. That is, the ejection head unit 11 ejects the solution while keeping a certain distance from the substrate 14 and performing relative movement in the X and Y directions parallel to the surface on which the functional device group is formed. 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 to each other in the two directions of the matrix arrangement, it is possible to form the device groups 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 highly accurate matrix-like array of functional devices can be obtained.
[0040]
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 two directions of X and Y) when positioning the substrate for the first time.
[0041]
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.
[0042]
As described above, this rotation position adjusting mechanism is connected to the substrate positioning / holding means 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.
[0043]
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.
[0044]
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.
[0045]
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 patterns such as the X-direction wiring and the Y-direction wiring may be regarded as the two-way band-shaped pattern of 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.
[0046]
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. That is, the ejection head unit 11 ejects a solution containing fine conductive fine particles while performing relative movement in the X and Y directions while maintaining a certain distance with respect to the substrate 14. The position control of the 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. .
[0047]
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 port surface of the ejection head unit 11 at the time of applying the solution of the present invention (at the time of ejection) is suppressed to 5 mm or less (the size of the substrate 14 is 100 mm × 100 mm or more). , 4000 mm x 4000 mm or less).
[0048]
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.
[0049]
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, and that is based on the optical axis 41 and the focal position of the detection optical system 32 and the ejection head 33. The droplets 43 are arranged so that the landing positions 44 of the droplets 43 coincide with each other.
[0050]
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.
[0051]
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.
[0052]
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.
[0053]
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 liquid droplets of the solution is sequentially performed in such two orthogonal directions.
[0054]
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 the two orthogonal directions. It is better to adopt a configuration in which
[0055]
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.
[0056]
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 with low electric resistance and high corrosion resistance can be formed. In addition, in addition to such a circuit pattern, for example, by using a solution containing fine particles of Pt or a nichrome material, a resistance element is manufactured, or Pd, Pt, Ru, Ag, Au, Ti, In, Metals such as Cu, Cr, Fe, Zn, Sn, Ta, W, Pb, PdO, SnO ₂ , In ₂ O ₃ , PbO, Sb ₂ O ₃ Oxides such as HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB ₄ , GdB ₄ By using a solution containing fine particles such as borides such as TiC, ZrC, HfC, TaC, SiC and WC, nitrides such as TiN, ZrN and HfN, semiconductors such as Si and Ge, and carbon. For example, an electron-emitting device can be manufactured.
In the present invention, the solution containing such fine conductive fine particles includes an aqueous solution and an oil solution.
[0057]
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.
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.
[0058]
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.
[0059]
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.
[0060]
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.
[0061]
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). Strictly speaking, it is determined in consideration of the dispersion stability of fine particles in the production of a solution, the occurrence of clogging during injection described later, and the surface roughness of a substrate on which a pattern is formed.
[0062]
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)).
[0063]
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).
[0064]
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.
[0065]
The content of the nanoparticles in the dispersion varies depending on the desired film (layer) structure or particle arrangement structure and the film (layer) thickness, but usually ranges from 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.
[0066]
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.
[0067]
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.
[0068]
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.
[0069]
Further, the organic compound can be dissolved in the dispersion. Examples of such organic compounds include trioctyl phosphine oxide (TOPO), thiophenol, photochromic compounds (such as spiropyran and fulgide), charge transfer complexes, and electron-accepting compounds, and those that 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.
[0070]
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 and drying process. good.
[0071]
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, but 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.
[0072]
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.
[0073]
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.
[0074]
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.
[0075]
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.
[0076]
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.
[0077]
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.
[0078]
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. 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).
[0079]
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 of the production efficiency of the conductive element).
[0080]
FIG. 8 shows a view of the multi-nozzle type liquid ejecting head manufactured in this manner, 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 as shown in FIG. 9 and mounted on a carriage. FIG. 10 is a perspective view thereof.
[0081]
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.
[0082]
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.
[0083]
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.
[0084]
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 terms of area). ² This clogging is a very serious problem, because a jetting head as described below must be used.
[0085]
By the way, clogging is derived from the very principle that a solution is ejected from a fine discharge port. That is, 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.
[0086]
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.
[0087]
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.
Although not shown in the drawing, 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 electroforming of Ni, and the thickness of the discharge port was 25 μm.
[0088]
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. After that, chlorine ions and nitrate ions were removed by an ultrafiltration membrane, and concentrated and dried to obtain a concentrated Ag fine particle-containing solution.
[0089]
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 manufacture 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 stable ones could not be obtained. The content of Ag fine particles in each solution was 10% by weight, and the resin content in the solution was 20% by weight. Also, the amount of ethylene glycol added was adjusted, and the viscosity of each solution was unified to 20 centipoise.
[0090]
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.
[0091]
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 used practically 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.
[0092]
[Table 1]

[0093]
[Table 2]

[0094]
[Table 3]

[0095]
[Table 4]

[0096]
From the above results, in the case where the ejection head having an ejection diameter of Φ5 μm to Φ20 μm is used, the Ag fine particle diameter Dp and the ejection opening diameter Do are not clogged 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 stably dispersing such very fine fine particles in a solution. In order to stably eject liquid droplets to all the ejection heads having a discharge opening 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 diameter Dp of the Ag fine particles and the diameter Do of the discharge port satisfy 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.
[0097]
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.
[0098]
In the experiment, an ejection head using a piezo element as a driving force for discharging liquid droplets was used, but the ejection head used in the manufacturing apparatus of the present invention is not limited to this, and the driving force is an electrostatic force between two electrodes. An electrostatic method that generates mechanical displacement of the diaphragm in the liquid chamber can also be used favorably. Since these provide mechanical working force to the liquid, there is an advantage that the liquid to be used is hardly restricted. Further, since this mechanical displacement can be displaced in an analog manner, the shape of the flying droplet can be made to be a round shape by controlling the drive waveform. For example, as will be described later, in the present invention, the driving waveform is controlled to form flying droplets having a round shape and a good dot pattern is obtained. This will be described later.
[0099]
In addition, it is also possible to use a jet head of a method in which film boiling bubbles are instantaneously generated in a liquid by heat and the growth power of the bubbles is used as a driving force for solution discharge. Alternatively, a charge control method (continuous flow method) or the like in which an electric charge is applied to droplets continuously ejected and the droplets are deflected according to the amount of the electric charge can be used.
In the method of generating film boiling bubbles using a thermal head or the like, since heat is used, the solution to be used may be thermally degraded.
[0100]
On the other hand, the method of generating film boiling air bubbles by using a thermal head or the like allows a 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. In addition, 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.
[0101]
Next, other features of the present invention will be described. As described above, in the present invention, a solution containing fine particles is stably ejected from a minute discharge port without causing clogging, but here, a droplet adheres to a substrate after the droplet ejection. The following shows the results of studying how to form a good pattern or device.
[0102]
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.
[0103]
At this time, a high-precision pattern or a functional device group can be formed by stopping the relative movement and performing the injection each time the fine particle-containing solution for forming the pattern or the functional device group is injected. However, since the productivity is remarkably reduced, the solution is sequentially jetted without stopping the relative movement. In this case, the relative moving speed (for example, the moving speed of the carriage in the X direction in FIG. 2) should not be determined merely by improving the productivity, but also from the viewpoint of forming a highly accurate pattern or a functional device group. Must be considered.
[0104]
In the present invention, as a result of intensive studies on this point, it has been found that, when such a fine particle-containing solution is injected, the injection speed must be higher than the relative movement speed. When forming the pattern or the functional device group by performing the ejection of the fine particle-containing solution while performing the relative movement in the X and Y directions while keeping the ejection head unit 11 at a fixed distance with respect to the substrate 14 as described above, The liquid droplets of the solution are attached and formed on the substrate 14 at the speed of the combined vector of the relative speed and the jet speed. Regarding the positional accuracy, the droplets are attached to the target positions by appropriately selecting the timing of the ejection in consideration of the distance between the substrate 14 and the solution ejection surface of the ejection head unit 11 and the speed of the combined vector. Can be done.
[0105]
However, even if the relative velocity is too high, if the relative velocity is too high, the liquid droplets are dragged by the relative velocity and flow on the substrate 14 to form a pattern with a good shape. Or a functional device group cannot be formed. The present invention has examined this point. The following is an example of the study results. In this example, the apparatus shown in FIG. 2 is used to change the moving speed of the carriage 12 in the X direction and the ejection speed of the ejection head unit 11 so that good droplets can be attached to the substrate 14 and a good pattern can be formed. I checked whether it can be done.
[0106]
FIG. 11 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. 11 (A) is good (○), and as shown in FIG. 11 (B), each dot pattern does not have a good round shape, but has an oval shape. Are out of position and come into contact with an adjacent dot pattern are defective (x).
[0107]
In addition, this is often caused by deterioration of jetting performance due to an initial stage of clogging or generation of a flaw in a discharge port. However, fine droplets scattered around are also defective (x).
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.
[0108]
Details of the experimental conditions are shown below. The substrate used was a glass substrate with an ITO transparent electrode. The solution containing the Ag fine particles described above (here, a fine particle having a particle size of 0.01 μm was used) was combined with the H4 jet head (nozzle diameter Φ5 μm). A pattern 83 such as 11 was formed. Note that FIG. 11 shows a diagram in which a space between a pair of ITO transparent electrodes 82 is formed to be filled with four dots for simplicity. However, actually, dots of about Φ8 μm are formed in one row in the vertical direction. Approximately 1000 are implanted at a pitch of about 4 μm to connect the upper and lower ITO transparent electrodes 82 (inter-electrode distance: 4 mm). In addition, a similar ITO transparent electrode 82 and a similar pattern connecting the ITO transparent electrodes 82 are formed adjacent to each other with a center distance of 12 μm.
[0109]
The ejection head used was an H4 ejection head having 64 nozzles (discharge ports) and an arrangement density of 100 dpi. The jet head and the substrate perform relative movement (here, the substrate is fixed, the jet head scans the carriage), the control is performed on the order of μ, and the timing of the jet is controlled. , And a pattern was formed while maintaining the center-to-center distance of 12 μm.
[0110]
The driving voltage of the droplet ejection changes the input voltage to the piezo element from 14 V to 21 V in order to change the ejection speed. The driving frequency was 10 kHz. In the ejection head using such a piezo element, the ejection speed can be changed by changing the input voltage to the piezo element, but the mass of the ejected droplet also changes at the same time. (Falling waveform) was controlled so that the volume of the ejected droplets was always substantially constant (1 pl), and only the ejection speed was changed.
[0111]
In addition, the shape of the droplet at the time of droplet flight is separately jetted and observed under the same conditions as the element formation, and the drive waveform is changed so that the shape becomes a substantially round droplet immediately before adhering to the substrate surface (3 mm in the present invention example). Was controlled and injected (FIG. 12). Even if a completely round sphere cannot be obtained, and even if it is a column extending in the flight direction, it can be easily made to have a length within three times its diameter (l ≦ 3d) only by controlling the drive waveform. (FIG. 13). At that time, a driving condition (driving waveform) that does not involve a plurality of minute droplets (satellite minute droplets 81) behind the flying droplet as described later (FIG. 14) was selected. The results are shown below.
[0112]
[Table 5]

[0113]
From the above results, it can be understood that when the moving speed of the carriage in the X direction is higher than the ejection speed, a good pattern cannot be formed, and the resistance value between the electrodes is out of aim. In other words, as in the present invention, when a droplet containing a nanoparticle-containing solution is applied to a substrate by an apparatus using an ejection head using a piezo element, and dried to form a pattern wiring or form a functional device, It can be seen that the speed of the droplet ejected from the ejection head must be faster than the moving speed of the carriage in the X direction.
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 velocity of the ejected droplet must be faster than the relative movement speed of the ejection head and the substrate.
[0114]
In addition, the droplet flight conditions this time were set to drive conditions (drive waveforms) that do not involve a plurality of minute droplets (satellite minute droplets 81) behind the flying droplet (FIG. 14) as described above. As a result, the plurality of fine droplets did not adhere to unnecessary portions at all, and a very good pattern could be formed.
Even if the flying droplet has a columnar shape extending in the flying direction, the length of the flying droplet is made to be less than three times its diameter (l ≦ 3d) by driving waveform control (FIG. 13). The formed dots also had a shape close to a perfect circle, and a good pattern could be formed.
[0115]
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.
[0116]
On the other hand, as shown in FIG. 16, if the particles have a size smaller than the irregularities, 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.
[0117]
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) was ejected in combination with the above-described H4 ejection head (nozzle diameter Φ5 μm) to form a pattern in which dots were connected, and the smoothness of the pattern was observed under a microscope. Sensory evaluation was performed to determine good to acceptable to poor (（to Δ to ×).
[0118]
Details of the experimental conditions are shown below. The pattern is one line in the vertical direction, in which about 100 dots of about Φ8 μm are formed at a pitch of about 4 μm.
The ejection head used was an H4 ejection head having 64 nozzles (discharge ports) and an arrangement density of 100 dpi. The jet head and the substrate perform relative movement (here, the substrate is fixed, the jet head scans the carriage), the control is performed on the order of μ, and the timing of the jet is controlled. Was done.
[0119]
The drive voltage for droplet ejection was 15 V input voltage to the piezo element, and the drive frequency was 10 kHz. The volume of the ejected droplet is always approximately 1 pl. In addition, the shape of the droplet at the time of droplet flight is separately ejected and observed under the same conditions as the pattern formation, and the drive waveform is changed so that the shape becomes a substantially round droplet immediately before adhering to the substrate surface (in the present example, 3 mm). Was controlled and injected (FIG. 12). Even if a completely round sphere cannot be obtained, and even if it is a column extending in the flight direction, it can be easily made to have a length within three times its diameter (l ≦ 3d) only by controlling the drive waveform. (FIG. 13). At this time, a driving condition (driving waveform) that does not involve a plurality of minute droplets (satellite minute droplets 81) behind the flying droplet as shown in FIG. 14 was selected.
[0120]
As described above, Ag fine particle-containing solutions having different particle diameters from 0.0005 μm to 0.2 μm were prepared and used (solution No. is common), but when the particle diameter is 0.02 μm or more, Since clogging of the nozzles began to occur, among the formed patterns, only those which had no clogging and had a good pattern were selected and evaluated. The results are shown below.
[0121]
[Table 6]

[0122]
From the above results, it can be seen that smooth fine patterns can be formed by setting the fine particles contained in the solution to have a size equal to or less 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.
[0123]
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.
[0124]
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.
[0125]
In other words, according to the present invention, by using a substrate having a surface roughness on the back side larger than the surface on which the pattern of the substrate is formed, a high-precision pattern wiring substrate or a functional device substrate can be obtained, and the substrate manufacturing cost can be reduced. 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.
[0126]
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.
[0127]
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.
[0128]
The second is that it is better to roughen the back surface of the substrate or the substrate holding surface. The substrate holding table 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.
[0129]
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.
[0130]
In the case where a plurality of minute suction holes are formed on the substrate holding surface of the substrate holding table and the substrate is held by vacuum suction, the surface on which the suction holes are formed is the present invention. It is regarded as having a roughened surface.
[0131]
Next, still another feature of the present invention will be described. The present invention sprays and applies a plurality of droplets of a solution containing fine particles to a substrate or a region where an electrode is formed on a substrate, volatilizes volatile components in a droplet pattern after the application, and solidifies the solid on the substrate. In addition, this is a technique of forming a pattern wiring or a device by combining patterns of dots of droplets by remaining on an electrode region.
[0132]
Here, a region where a pattern wiring or a device is formed by a pattern of dots of the droplet is a band-shaped pattern having a certain area (FIGS. 17 to 19). FIG. 17 shows an example in which a circuit pattern is formed by connecting two terminals 91 by a linear wiring pattern by means of a dot pattern 92 of droplets of the present invention. It is a band-shaped pattern extending in the direction of the arrow in the figure.
[0133]
FIG. 18 is also an example in which a circuit pattern is formed by connecting the two terminals 91 by a wiring pattern of a dot pattern 92 of the liquid droplet of the present invention. In this case, the wiring pattern is formed by bending. . It is not always a straight line in circuit design, and a bent wiring is often formed as in this example. Also in this case, it is a band-shaped pattern extending in the directions of two arrows in the figure.
[0134]
FIG. 19 shows an example in which a device is formed by forming a dot pattern 92 of the liquid droplets of the present invention between two element electrodes 93 in the same manner.
In these examples, in the present invention, since such a band-shaped pattern functions as a pattern wiring or an electronic device, the region has no uncovered region such as a pinhole.
[0135]
This will be described with reference to FIG. FIG. 20 shows the band-shaped pattern area of the present invention. In the figure, lx and ly are the centers of dots in the X direction and Y direction (X and Y are two directions orthogonal to each other) in the dot pattern 92, respectively. The distance (pattern pitch) is shown. D is the diameter of the dot of the dot pattern 92.
[0136]
In the present invention, as described above, in order to eliminate the non-covered area in the area of such a band-shaped pattern, the dot diameter d of the adjacent dots in two orthogonal directions is set to the distance between the centers in the two orthogonal directions. The nozzle diameter of the ejection head or the droplet forming conditions are selected so as to be √2 times or more of lx or ly. In the example of FIG. 20, the dot diameter d is actually set to √2 times or more of the center distance lx or ly in two orthogonal directions, and the vertical (X direction), horizontal (Y direction), and oblique Since each dot pattern is formed so as to overlap with each other, it is a band-shaped pattern having no uncovered area.
[0137]
In the examples of FIGS. 17 to 19, for simplification of the drawing, the dot diameter d shows an example in which the center-to-center distance lx or ly is 、 2 times. This is a critical condition where no uncovered area exists, and by forming a dot pattern at a density higher than this, a band-shaped pattern having no uncovered area can be formed.
[0138]
The arrows shown in FIGS. 17 and 18 indicate the directions in which the belt-shaped pattern extends, and these arrows and directions opposite to the arrows by 180 degrees have been described with reference to FIGS. When the directions are parallel to the X direction and the Y direction, that is, the direction of each side of the rectangular substrate, or the direction of the matrix arrangement of the functional device group, positioning or formation of each pattern can be performed with high precision. Therefore, basically, the band-shaped pattern is a pattern extending in the directions parallel to the X direction and the Y direction described with reference to FIGS. 2 to 4 described above. Even in the case of a band pattern in a different direction, or a band pattern on a curved line instead of a straight line, such image pattern formation information can be input to the ejection head by computer control. At this time, needless to say, the strip-shaped pattern of the present invention is a pattern having no uncovered area.
[0139]
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 prepared by dispersing a myriad of fine particles and nanoparticles in a solution containing fine particles and nanoparticles in the air by the principle of ink jet, and forming droplets on the substrates as droplets. In order to stably manufacture substrates with high-quality functions over a long period of time, the manufacturing equipment must maintain stable and constant performance. No. The most important point here is the long-term performance stability of the ejection head.
[0140]
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 of the discharge port (nozzle) are problematic because they affect the droplet ejection performance of the solution.
[0141]
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 this has an effect on the droplet ejection performance of the ejection head, it is considered that the extent of the influence depends on the size of the scratch 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.
[0142]
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 used ejection head is the same as the above-described H1 ejection head to H3 ejection head. That is, the piezo element 46 as shown in FIGS. 5 and 6 is used as a driving force for droplet discharge, and the mechanical displacement of the piezo element 46 as an electro-mechanical conversion element is regarded as the displacement of the diaphragm of the liquid chamber. Thus, a droplet is ejected from a fine discharge port.
Although not shown in the figure, an ejection head having a structure in which a nozzle plate having a nozzle hole separately formed on the nozzle 1 surface is provided. The number of nozzles is 64, and the array density is 100 dpi.
[0143]
By performing the solution ejection for a certain period of time using such an ejection head, it is determined whether or not the ejection opening (nozzle hole) is damaged. It was examined whether the pattern shape was good or bad and the pattern performance deteriorated (resistance change). 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.
The drive voltage of the ejection head was 20 V, the drive frequency was 10 kHz, continuous ejection was performed for 100 hours, and the ejection port portion after the ejection was observed by SEM to check for the presence or absence of flaws.
Discharge diameters of Φ20 μm (H1 ejection head), Φ15 μm (H2 ejection head), and Φ10 μm (H3 ejection head) were prepared.
[0144]
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 60 dpi. The driving voltage of the ejection head was 30 V, the driving frequency was 3.8 kHz, and continuous ejection was performed for 260 hours.
[0145]
The thickness of the nozzle plate was 30 μm for the H1 and H2 ejection heads, 20 μm for the H3 ejection head, and 40 μm for the reference head. The velocity of the droplet at the time of ejection was about 7 m / s in each of the ejection heads.
[0146]
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 by punching 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.
[0147]
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. 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.
[0148]
[Table 7]

[0149]
The results of evaluation using these sample solutions and jet heads are shown below. In the table, the mark ○ indicates that no noticeable scratch was observed after 100 hours of injection, and the mark 多数 indicates that there were a number of scratches that could affect the nozzle shape or dimensions. In the pattern shape, “○” indicates that the dot pattern was formed in a good round shape at a target position (between a pair of electrodes) when the pattern was formed after 100 hours of injection (FIG. 11A), and × Indicates that the position is slightly out of the target position, the shape is irregular, or the microdroplets are scattered around (FIG. 11B). × 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 was when the resistance value when the pattern was produced after 100 hours of ejection was abnormally large or short-circuited (impractical level). is there. The injection time for the reference head is 260 hours.
[0150]
[Table 8]

[0151]
[Table 9]

[0152]
[Table 10]

[0153]
[Table 11]

[0154]
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. In other words, in the present invention, the member constituting the discharge port needs to be made of a material harder than the fine particles.
[0155]
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.
[0156]
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.
[0157]
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.
[0158]
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.
[0159]
【The invention's effect】
In a droplet jet manufacturing apparatus for manufacturing a patterned wiring substrate or a device substrate by jetting a plurality of droplets of a fine particle-containing solution by an injection head having a discharge opening diameter of 20 μm or less, the surface roughness of a surface on which a substrate pattern is formed Was made coarser than the size of the fine particles, in other words, since the size of the fine particles was finer than the surface roughness of the substrate, high-precision pattern formation was 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 is formed, thereby realizing cost reduction of the substrate. Furthermore, by optimizing the size and ejection diameter of the fine particles to achieve stable ejection without clogging, the droplets are ejected by the action force due to mechanical displacement, ejecting droplets that are easy to form good dots Therefore, a good dot pattern can be formed. In addition, since the pattern to be formed is a band-shaped pattern in which no uncovered area exists in the area where the pattern is formed by combining the dots formed by the droplets, high precision and high quality by a novel method are achieved. Pattern wiring boards or device substrates can be manufactured stably at low cost.
[0160]
Further, in a droplet jet manufacturing apparatus for manufacturing a pattern wiring substrate or a device substrate by jetting a plurality of droplets of a fine particle-containing solution by an injection head having an ejection diameter of 20 μm or less, the surface of the surface on which the pattern of the substrate is formed. Since the roughness was made larger than the size of the fine particles, in other words, the size of the fine particles was finer than the surface roughness of the substrate, high-precision pattern formation was 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 is formed, thereby realizing cost reduction of the substrate. Furthermore, by optimizing the size of the fine particles and the diameter of the discharge port, realizing stable jetting without clogging, the droplets are jetted by the action force due to mechanical displacement, and the flying distance is shortened. Is higher than the relative movement speed between the substrate and the ejection head, so that a good dot pattern can be formed. Furthermore, since the pattern to be formed is made to be a band-shaped pattern in which the uncovered area does not exist in the area where the pattern is formed by a combination of dots formed by droplets, high precision and high quality by a novel method Pattern wiring boards or device substrates can be manufactured stably at low cost.
[0161]
In addition, in the above-described liquid droplet ejection manufacturing apparatus, since the ejection port of the ejection head is an opening formed in a substrate made of a material harder than the fine particles in the solution containing fine particles, scratches are generated in the discharge port even after long-term use. Since it does not break or break, a high-quality patterned wiring board or device board can be manufactured stably for a long period of time.
[0162]
Further, in the pattern wiring substrate manufactured by the above-described droplet jet manufacturing apparatus, the surface roughness of the surface on which the pattern of the substrate is formed is made larger than the size of the fine particles, in other words, the size of the fine particles is Since it is finer than the surface roughness, highly accurate pattern formation was 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 is formed, thereby realizing cost reduction of the substrate. Further, the pattern to be formed is a band-like pattern by a combination of droplet patterns, and the non-covered area is not present in the area where the pattern is formed, so that a pattern wiring board provided with high-precision and high-quality functions Was realized.
[0163]
Further, in the pattern wiring substrate manufactured by the above-described droplet jet manufacturing apparatus, the surface roughness of the surface on which the pattern of the substrate is formed is made larger than the size of the fine particles, in other words, the size of the fine particles is Since it is finer than the surface roughness, highly accurate pattern formation was 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 is formed, thereby realizing cost reduction of the substrate. Furthermore, the size of the fine particles and the diameter of the discharge port have been optimized, so that they can be manufactured by stable jetting without clogging, and high-precision pattern formation has been realized. In addition, the pattern to be formed is a band-like pattern by a combination of droplet patterns, and since there is no uncovered area in the area where the pattern is formed, a pattern wiring board provided with high-precision and high-quality functions Was realized.
[0164]
Further, in the pattern wiring substrate manufactured by the above-described droplet ejection manufacturing apparatus, the fine particles in the pattern are made of a material softer than the member constituting the ejection port of the ejection head. A high-quality patterned wiring substrate can be obtained without causing any damage or breakage at the exit.
[0165]
In the device substrate manufactured by the above-described droplet jet manufacturing apparatus, the surface roughness of the surface on which the device of the substrate is formed is made larger than the size of the fine particles, in other words, the size of the fine particles is smaller than the surface of the substrate. Since it is finer than the roughness, high-precision device 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 devices are formed, thereby realizing cost reduction of the substrate. Furthermore, the device pattern to be formed is formed into a band pattern by a combination of the dot patterns of the liquid droplets, and the non-covered region is not present in the region where the device pattern is formed, so that high-precision and high-quality functions are provided. Device substrate is realized.
[0166]
Also, in a device substrate manufactured by the above-described droplet jet manufacturing apparatus, the surface roughness of the surface on which the device of the substrate is formed is made larger than the size of the fine particles, in other words, the size of the fine particles is smaller than the surface of the substrate. Since it is finer than the roughness, high-precision device 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 devices are formed, thereby realizing cost reduction of the substrate. Furthermore, since the size of the fine particles and the diameter of the discharge port are optimized, the device can be manufactured by stable jetting without clogging, and a high-precision device pattern can be formed. In addition, the device pattern to be formed is a band-shaped pattern by a combination of the dot patterns of the droplets, and there is no uncovered area in the region where the device pattern is formed, so that high-precision and high-quality functions are provided. Device substrate is realized.
[0167]
Further, in the device substrate manufactured by the above-described droplet ejection manufacturing apparatus, the fine particles in the device pattern are made of a material softer than the member constituting the ejection port of the ejection head. A high-quality device substrate can be obtained without being damaged or damaged at the outlet.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an embodiment of a pattern wiring formed by a droplet jet manufacturing apparatus of the present invention.
FIG. 2 is a diagram for explaining an embodiment of a droplet 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 a droplet 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 droplet applying apparatus applied to the manufacture of a patterned wiring substrate or a device substrate according to the present invention.
FIG. 5 is a view for explaining the principle of droplet ejection of an ejection head utilizing a piezo element which is suitably used in the present invention.
FIG. 6 is a view showing the structure of a jet head utilizing a piezo element which is suitably used in the present invention.
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 the head unitized as described above.
FIG. 11 is a diagram showing an example of a test pattern used for finding conditions for forming a good pattern by the droplet jet manufacturing apparatus of the present invention.
FIG. 12 is a view for explaining an example of a droplet flying shape when the ejection head used in the droplet ejection manufacturing apparatus according to 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 droplet ejection manufacturing apparatus of the present invention ejects with an acting force due to mechanical displacement.
FIG. 14 is a view for explaining an example of a droplet flying shape when ejected by the action force of film boiling bubbles.
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 for explaining an example of a belt-shaped pattern according to the present invention.
FIG. 18 is a view for explaining another example of the strip pattern of the present invention.
FIG. 19 is a diagram illustrating an example of a device pattern according to the present invention.
FIG. 20 is a diagram for explaining conditions for preventing an uncovered area from being generated in the dot pattern of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Wiring pattern, 2, 3 ... Terminal, 10 ... Substrate, 11 ... Discharge head unit (ejection head), 12 ... Carriage, 13 ... Substrate holder, 14 ... Substrate, 15 ... Supply tube of solution containing fine particles, 16 ... Signal supply cable, 17: injection head control box, 21: control box, 18: X direction scan motor, 19: Y direction scan motor, 20: computer, 22: substrate positioning / holding means, 31: head alignment control mechanism, 32 ... detection optical system, 33 ... ejection head, 34 ... head alignment fine movement mechanism, 36 ... image identification mechanism, 37 ... XY direction scanning mechanism, 38 ... position detection mechanism, 39 ... position correction control mechanism, 40 ... ejection head driving and control Mechanism: 41: optical axis, 42: element electrode, 43: droplet, 44: droplet landing position, 45: flow path, 46: Ezo element, 47 solution, 48 nozzle, 49 filter, 65 nozzle, 66 heating element substrate, 67 lid substrate, 68 silicon substrate, 69 individual electrode, 70 common electrode, 71 heating element, 74 ... groove, 75 ... concave area, 76 ... solution inlet, 81 ... satellite microdrop, 82 ... device electrode (ITO transparent electrode), 83 ... dot pattern, 84 ... microdrop, 85 ... fine particle, 86 ... substrate surface, 91: terminal, 92: dot pattern, 93: element electrode.

Claims (9)

A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge diameter of 20 μm or less to form a pattern on the substrate and the electrode region, and the volatile components in the applied droplet pattern are volatilized. In the droplet 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 roughness of the surface of the substrate on which the pattern is formed is reduced to the size of the fine particles. When the surface roughness of the back surface of the substrate is made coarser than the surface roughness of the surface on which the pattern is formed, 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 ejects the droplet by an acting force due to mechanical displacement, and attaches the shape of the droplet when the droplet flies to the substrate surface. A droplet jet manufacturing apparatus which is formed into a round droplet immediately before the droplet is formed, or a column extending in the flight direction and having a length of not more than three times its diameter so that a plurality of fine droplets are not accompanied behind the flying droplet. The droplet jet manufacturing apparatus, wherein the pattern is a band-shaped pattern in which an uncovered region does not exist in a region where the pattern is formed, by a combination of dots formed by the droplets. A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge diameter of 20 μm or less to form a pattern on the substrate and the electrode region, and the volatile components in the applied droplet pattern are volatilized. In the droplet 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 roughness of the surface of the substrate on which the pattern is formed is reduced to the size of the fine particles. When the surface roughness of the back surface of the substrate is made greater than the surface roughness of the surface on which the pattern is formed, the size of the fine particles is Dp, and the discharge port diameter is Do, 0.0001 ≦ Dp /Do≦0.01, the ejecting head ejects the droplet by an acting force due to mechanical displacement, and makes the flying distance within 3 mm, A droplet ejection manufacturing apparatus that ejects droplets at an ejection speed higher than a relative movement speed between the substrate and the ejection head, wherein the pattern is formed by a combination of dots formed by the droplets. A droplet ejection manufacturing apparatus, wherein a strip-shaped pattern in which an uncovered area does not exist in an area to be covered is provided. The apparatus according to claim 1, 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. A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an action force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region to form a pattern wiring or a device. In a patterned wiring board provided with a function manufactured by a droplet jet manufacturing apparatus to be formed, the surface of the patterned wiring board on which the pattern is formed is made coarser than the size of the fine particles, and the back surface of the substrate is formed. Surface roughness of the surface on which the pattern is to be formed is rougher than that of the surface on which the pattern is formed, and the pattern has no uncovered region in the region where the pattern is formed due to a combination of dots formed by the droplets. A pattern wiring board, which is a belt-shaped pattern. A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an action force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region to form a pattern wiring or a device. In a patterned wiring board provided with a function manufactured by a droplet jet manufacturing apparatus to be formed, the surface of the patterned wiring board on which the pattern is formed is made coarser than the size of the fine particles, and the back surface of the substrate is formed. Is made coarser than the surface roughness of the surface on which the pattern is formed, and the fine particles in the pattern have a size of Dp and a discharge port diameter of Do, where 0.0001 ≦ Dp / Do ≦ 0.01 and the pattern is formed by a combination of dots formed by the droplets. A pattern wiring board, wherein the pattern wiring board has a band-shaped pattern in which no uncovered area exists. The pattern wiring board according to claim 4, wherein the fine particles in the pattern are made of a material softer than a member constituting the discharge port. A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an action force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region to form a pattern wiring or a device. In a device substrate provided with a function manufactured by a droplet jet manufacturing apparatus to be formed, the surface roughness of the surface of the device substrate on which the device is formed is made larger than the size of the fine particles, and the surface of the back surface of the substrate is formed. The roughness of the device is made rougher than the surface roughness of the surface on which the device is formed, and the pattern of the device has no uncovered region in the region where the pattern is formed due to a combination of dots formed by the droplets. A device substrate having a belt-like pattern. A plurality of droplets of the fine particle-containing solution are ejected onto the substrate by an ejection head having a discharge port diameter of Φ20 μm or less by an action force due to mechanical displacement, and a pattern is formed on the substrate and the electrode region to form a pattern wiring or device. In a device substrate provided with a function manufactured by a droplet jet manufacturing apparatus to be formed, the surface roughness of the surface of the device substrate on which the device is formed is made larger than the size of the fine particles, and the surface of the back surface of the substrate is formed. The roughness is made coarser than the surface roughness of the surface on which the device is formed, and the fine particles have a size of Dp and a discharge port diameter of Do, where 0.0001 ≦ Dp / Do ≦ 0.01, The pattern of the device has an uncovered area in an area where the pattern is formed by a combination of dots formed by the droplets. A device substrate, wherein the device substrate has a band-shaped pattern having no area. The device substrate according to claim 7, wherein the fine particles in the pattern are made of a material softer than a member forming the discharge port.

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