JP3896348B2 - Droplet jet manufacturing apparatus, pattern wiring board manufactured thereby, and device board - Google Patents

Description

【００９８】
【表２】

【００９９】
【表３】

【０１００】
【表４】

【０１０１】
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。
【０１０２】
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。
【０１０３】
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、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。
【０１０４】
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。
【０１０５】
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。
【０１０６】
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。
【０１０７】
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。
【０１０８】
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。
【０１０９】
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。
【０１１０】
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。
【０１１１】
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１例を示す。この例は、図２のような装置を用い、キャリッジ１２のＸ方向移動速度、ならびに吐出ヘッドユニット１１の噴射速度を変えて、基板１４上で良好な液滴付着ができ、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。
【０１１２】
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。
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。
【０１１３】
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）。
【０１１４】
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のようなパターンを形成した。なお、図１１は簡略化のため、１対のＩＴＯ透明電極間を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透明電極およびＩＴＯ透明電極間をつなぐ同様のパターンを形成している。
【０１１５】
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。
【０１１６】
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。
【０１１７】
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を伴うことのない駆動条件（駆動波形）を選んだ。以下の表５に結果を示す。
【０１１８】
【表５】

【０１１９】
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。
【０１２０】
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。
【０１２１】
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。
【０１２２】
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。
【０１２３】
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もしくはシートは、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、基板上もしくはシート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もしくはシートを製作するためには、基板もしくはシート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もしくはシート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、基板もしくはシート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、基板もしくはシート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。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。
【０１２４】
実験は、パイレックス（登録商標）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。
【０１２５】
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。
【０１２６】
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を伴うことのない駆動条件（駆動波形）を選んだ。
【０１２７】
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。以下の表６に結果を示す。
【０１２８】
【表６】

【０１２９】
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。
【０１３０】
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ＳｉＯ₂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ＳｉＯ₂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。
【０１３１】
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。
【０１３２】
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。
【０１３３】
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。
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。
【０１３４】
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。
【０１３５】
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。
【０１３６】
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。
【０１３７】
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。
【０１３８】
次に、本発明のさらに別の特徴について説明する。図１７は、本発明の原理によって形成されるパターン配線基板のパターン配線の１例である。基板上に先に形成されている矩形あるいは矩形の組み合わせによって構成された端子パターン（電極パターン）に、あとから微粒子含有溶液を噴射し、配線パターンを形成した例である。なおこの例では、図が複雑になるのを避けるために、配線パターンのドッドが隣接斜め方向においてちょうど互いに接触するように配置しているが、実施には互いにもう少し高密度に配置し（＝互いのドットの重なり部分を多くとるように配置し）、配線パターン部分に非被覆部が生じないようにする。
【０１３９】
図１８は、本発明の原理によって形成されるデバイス基板の１デバイスの例である。基板上に先に形成されている矩形あるいは矩形の組み合わせによって構成された１対の素子電極（電極パターン）に、あとから微粒子含有溶液を噴射し、デバイスを形成した例である。
【０１４０】
しかしながらここで１つ問題がある。それは、回路パターンあるいは各種デバイスとして完成した後に使用する際に発生する端子パターンや素子電極（電極パターン）部における異常放電である。図１７、図１８を用いて説明する。
【０１４１】
本発明では、図１７、図１８のように複数（この例は２）個の端子パターン（電極パターン）間に金属微粒子材料を含有する溶液のドットパターンによって配線パターンを形成したり、対向する素子電極間に金属微粒子材料を含有する溶液のドットパターンによって各種電子デバイスを形成するが、通常、これらの端子パターンや素子電極（電極パターン）はＡｌ、Ａｕ、Ｃｕ等の薄膜やＩＴＯ薄膜で形成され、フォトリソグラフィー、エッチング等によって、所望のパターン形状にされる。通常は矩形パターンもしくは矩形パターンの組み合わせによって構成されることが多い。
【０１４２】
これは、このような電極パターンをフォトリソグラフィー技術によって形成する際のフォトマスクの形状に依存して、矩形形状にされる（矩形が最もコスト的に製作しやすい）わけであるが、図１７、図１８に示すように電極パターンのコーナー部が尖っているために、その部分で電界集中が生じる。その結果、両電極間に印加して使用する際に、この電界集中部において異常な放電が生じ、良好な素子性能が得られないという不具合がある。
【０１４３】
本発明ではこの点に鑑み、例えば図１９、図２０のように電極パターンのコーナー部を面取り形状としている。この例は、機械図面で表示する際のｃ形状の面取りとしているが、ｒ形状の面取りであってもいいのは言うまでもない。
【０１４４】
このような形状は、素子電極パターンをフォトリソグラフィー技術によって形成する際にフォトマスクの形状をそのようなコーナー部が尖った形状にならないようにすればよい。
【０１４５】
なお、その面取り部分の大きさであるが、通常はドットパターン径の１／２〜１／５程度、すなわちｃ２μｍ〜ｃ５μｍ、あるいはｒ２μｍ〜ｒ５μｍとすれば、電界集中が生じない良好な素子電極とすることができる。
【０１４６】
本発明では、このように電極パターンの尖った部分をなくし、電界集中をなくすようにすることにより、回路パターンあるいは各種デバイスとして使用する場合に、異常放電がなく、また長期に使用しても安定した品質が得られるようになった。
【０１４７】
次に、本発明のさらに他の特徴について説明する。図２１、図２２は、前述の図１７〜図２０で説明した配線パターンあるいは電子デバイスと同等のものである。図１７〜図２０で説明したものは、電極パターンを形成するのに、基板上にあらかじめＡｌ、Ａｕ、Ｃｕ等の薄膜を形成し、フォトリソグラフィー、エッチング等によって、所望のパターン形状にしたものであるが、図２１、図２２に示したものは、この電極パターンを本発明の溶液噴射原理によって形成したものである。
【０１４８】
すなわち、Ａｇ等の導電性材料の微粒子を含有した溶液を使用し、前述のようなパターン配線あるいはデバイスパターン形成と同じように、電極パターンをドットの組み合わせとして形成したものである。このようにすることのメリットは、電極形成においても、図２〜図４で説明した本発明の製造装置が使用できる点の他に、前述の異常放電の問題を解決できる点にある。図２１、図２２に示すように、電極パターンを本発明の金属微粒子を分散させた溶液噴射によるドットパターンによって形成したものであれば、ドットパターンの外形そのものが丸い形状になっていて尖った部分がないので、自動的に面取り形状とすることができる。
【０１４９】
なお、図２１、図２２に示したものは、電極パターン部のドット径が配線パターン部あるいは、デバイスパターン部のドット径より大きなものとしたが、これは同じ吐出口径をもつ同じ噴射ヘッドを使用して、ドットパターンが同じ大きさになるようにしてもよい。
【０１５０】
ところで、図１７に示したドットの組み合わせによる配線パターンは、縦長方向に伸びた帯状パターンとして形成されるあるいは、図１８のデバイスにおいても、ドットパターンは帯状パターンとして形成されるが、このような帯状パターンが伸びている方向は、前述の図２〜図４で説明したＸ方向あるいはＹ方向、すなわち基板と噴射ヘッドとの相対移動方向（噴射ヘッドを搭載したキャリッジ移動方向、あるいは基板移動方向）と平行にすることにより、溶液を噴射制御するためのパターン情報およびその制御を単純化でき、高精度な各パターン形成を低コストで実現できる。
【０１５１】
また、同様にこれらの方向、すなわちパターンが伸びている方向は、使用する矩形基板の各辺の方向、あるいは形成されるデバイス群のマトリックス配列の方向と平行にすることにより、位置決め、あるいは各パターン形成を高精度にできる。
【０１５２】
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もしくはシートは、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、基板上もしくはシート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もしくはシート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。
【０１５３】
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。
【０１５４】
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。
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。
【０１５５】
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。
【０１５６】
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。
【０１５７】
このような噴射ヘッドを使用し、一定時間溶液噴射を行うことにより、吐出口部（ノズル孔部）にキズが生じるかどうか、また、溶液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。
【０１５８】
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。
【０１５９】
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。また、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。
【０１６０】
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。
【０１６１】
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。
【０１６２】
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。表７に、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。
【０１６３】
【表７】

【０１６４】
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の表８〜表１１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。
【０１６５】
【表８】

【０１６６】
【表９】

【０１６７】
【表１０】

【０１６８】
【表１１】

【０１６９】
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。
【０１７０】
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。
【０１７１】
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。
【０１７２】
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。
【０１７３】
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、数十μｍ〜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。
【０１７４】
【発明の効果】
上述したように、請求項１に記載の発明によれば、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、このパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されて、パターン配線基板あるいはデバイス基板を形成するが、この電極のパターンはコーナー部を面取り形状としているので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板あるいはデバイス基板を、新規な手法によって低コストでかつ安定して製作できるようになった。
【０１７５】
請求項２に記載の発明によれば、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、このパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されて、パターン配線基板あるいはデバイス基板を形成するが、この電極のパターンはコーナー部を面取り形状としているので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板あるいはデバイス基板を、新規な手法によって低コストでかつ安定して製作できるようになった。
【０１７６】
請求項３に記載の発明によれば、このような液滴噴射製造装置において、電極のパターンは、導電性微粒子含有溶液を噴射付与して形成されるドットパターンの組み合わせによって形成するようにしたので、電極パターンのコーナー部分を尖った形状ではなく丸く形成できるので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板あるいはデバイス基板を、新規な手法によって低コストでかつ安定して製作できるようになった。
【０１７７】
請求項４に記載の発明によれば、こ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。
【０１７８】
請求項５に記載の発明によれば、こ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、このパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されてパターン配線基板を形成するが、この電極パターンはコーナー部を面取り形状としたので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板を得ることができるようになった。
【０１７９】
請求項６に記載の発明によれば、こ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、このパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されてパターン配線基板を形成するが、この電極パターンはコーナー部を面取り形状としたので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板を得ることができるようになった。
【０１８０】
請求項７に記載の発明によれば、こ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、電極のパターンは、導電性微粒子含有溶液を噴射付与して形成されるドットパターンの組み合わせによって形成するようにしたので、電極パターンのコーナー部分を尖った形状ではなく丸く形成でき、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いパターン配線基板が得られるようになった。
【０１８１】
請求項８に記載の発明によれば、こ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。
【０１８２】
請求項９に記載の発明によれば、こ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、このデバイスパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されてデバイス基板を形成するが、この電極パターンはコーナー部を面取り形状としたので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いデバイス基板を得ることができるようになった。
【０１８３】
請求項１０に記載の発明によれば、こ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、このデバイスパターンは、溶液のドットパターンによって形成されるとともに、その端部が、基板上で電極パターンと電気的接続されてデバイス基板を形成するが、この電極パターンはコーナー部を面取り形状としたので、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いデバイス基板を得ることができるようになった。
【０１８４】
請求項１１に記載の発明によれば、こ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、電極のパターンは、導電性微粒子含有溶液を噴射付与して形成されるドットパターンの組み合わせによって形成するようにしたので、電極パターンのコーナー部分を尖った形状ではなく丸く形成でき、異常放電の起きない高品質でかつ信頼性が高く、また精度の高いデバイス基板が得られるようになった。
【０１８５】
請求項１２に記載の発明によれば、こ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】図９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】本発明の原理により、液滴あるいは溶液のドットを組み合わせてパターン配線を形成する例を説明するための図である。
【図１８】本発明の原理により、液滴あるいは溶液のドットを組み合わせてデバイスを形成する例を説明するための図である。
【図１９】図１７の例でコーナー部における異常放電を改良した例である。
【図２０】図１８の例でコーナー部における異常放電を改良した例である。
【図２１】図１７の例でコーナー部における異常放電を改良した他の例である。
【図２２】図１８の例でコーナー部における異常放電を改良した他の例である。
【符号の説明】
１ （液体噴射ヘッド）ノズル
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、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
５６ 溶液
５７ 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[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for forming a wiring board or a functional device by injecting a fine particle-containing material by using a discharge apparatus and forming a wiring substrate or a functional device, a material used therefor, 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 the application of such fine particles to a device, 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 densely integrated is specifically a light emitting device (LED) (Alivisatos et al.), A photoelectric conversion device (Greenham, NC, et al., Phys. Rev. B, 54, 17628 (1996). )), Ultrafast detectors (Bhargava), electroluminescence displays and panels (Bhargava, Alivisatos et al.), Nanostructured memory elements (Chen et al.), Multicolor devices consisting of nanoparticle arrays (Dushkin et al.) Application to etc. has been reported.
[0003]
On the other hand, as a method of forming an inorganic compound thin film having excellent orientation, molecular beam epitaxy (MBE), cluster ion beam, ion beam irradiation vacuum deposition, chemical vapor deposition (CVD), physical vapor deposition ( 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) or the like is known. In general, what is called a quantum dot can be manufactured using a process in which a source material sublimated in a high vacuum using a vacuum apparatus such as the MBE method described above forms dots on a solid substrate in a self-organizing manner. 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 it takes a great deal of cost to control to a desired structure. Therefore, as a technique that can solve such a problem, it has been proposed to form a film of a material containing fine particles by an ink jet principle, that is, a liquid jet head. For example, an ultra-fine particle (nanoparticle) that has the function to increase or memorize the photoluminescence intensity as a function of the irradiation time or dose of excitation light by inkjet coating an emulsion containing nanoparticles onto a solid substrate There has been proposed a method of forming a thin film comprising an assembly of the above on a solid substrate (for example, see Patent Document 1).
[0005]
In addition to such functional elements, studies have been made to apply the same principle to circuit board fabrication. For example, the following methods are conventionally known as a method for manufacturing a circuit board.
(1) A method in which a copper-clad laminate is coated with a resist, and a copper line pattern is formed by exposure of a circuit pattern, dissolution and removal of an unexposed resist, and etching of a resist removal portion by a photolithographic method.
(2) A method of forming a conductive pattern by printing a conductive paste on a ceramic substrate by screen printing in a desired circuit pattern and then heat-treating it in a non-oxidizing atmosphere to sinter metal fine particles in the conductive paste.
(3) A thin conductive layer is formed on the insulating substrate by vapor deposition of a conductive metal, and a resist is coated on the conductive layer, and exposure of the circuit pattern, dissolution and removal of the unexposed resist by the photolithography method, resist A method of forming a copper wire pattern by etching the removed portion.
[0006]
Since these methods have a problem that they are not suitable for forming a fine pattern, for example, a circuit pattern is directly drawn on a substrate with a metal paste using an ink-jet head so that the fine pattern can be easily formed. In addition, a wiring pattern forming method and a circuit board manufacturing method have been proposed which do not require waste liquid treatment, have a simple production process, and require less equipment and production costs (see, for example, Patent Document 2).
[0007]
On the other hand, the present inventor has also proposed an invention for manufacturing an electron source substrate using the ink jet principle (see, for example, Patent Document 3).
[0008]
[Patent Document 1]
JP 2000-126681 A
[Patent Document 2]
JP 2002-134878 A
[Patent Document 3]
JP 2001-319567 A
[0009]
[Problems to be solved by the invention]
However, various proposals using the ink-jet principle have begun to be made, but the idea of manufacturing various devices or pattern substrates by such means is still new, and a more specific method is still unknown. There are many, and the fact is that it is in a groping state.
[0010]
The present invention has been made in view of the above circumstances, and a first object thereof is a novel droplet ejection for producing a high-quality, high-accuracy and reliable pattern wiring board or device board with a high yield. It is to provide a manufacturing apparatus.
[0011]
A second object is to provide a droplet jet manufacturing apparatus of another configuration for manufacturing a high-quality, high-accuracy and reliable pattern wiring board or device board with a high yield.
[0012]
A third object is to propose a specific configuration for manufacturing a highly reliable pattern wiring substrate or device substrate with the droplet jet manufacturing apparatus having such a novel configuration.
[0013]
A fourth object is to ensure reliability in the long-term use of the droplet jet manufacturing apparatus having such a novel configuration.
[0014]
A fifth object of the present invention is to provide a pattern wiring board provided with a highly accurate, high quality and reliable function manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0015]
A sixth object is to provide a pattern wiring board to which a highly accurate, high quality and highly reliable function is provided which is manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0016]
A seventh object is to propose a specific configuration of the pattern wiring board provided with such a highly reliable function.
[0017]
An eighth object is to always provide the quality of such a patterned wiring board stably.
[0018]
It is a ninth object of the present invention to provide a device substrate having a highly accurate, high quality and highly reliable function manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0019]
A tenth object is to provide a device substrate having a highly accurate, high quality and reliable function, which is manufactured by the droplet jet manufacturing apparatus having such a novel configuration.
[0020]
An eleventh object is to propose a specific configuration of the device substrate to which such a highly reliable function is given.
[0021]
A twelfth object is to always provide the quality of such a device substrate stably.
[0022]
[Means for Solving the Problems]
  In order to achieve the above object, the present invention firstly, sprays droplets of a fine particle-containing solution on an electrode pattern formed on a substrate and on the substrate by an ejection head having an ejection port diameter of Φ20 μm or less, On substrate and electrode areaDotIn the droplet jet manufacturing apparatus for forming a pattern wiring or a device by forming a pattern, volatilizing a volatile component in a droplet pattern after application, and leaving a solid content on the substrate and the electrode region, the fine particle When the size of Dp is Dp and the diameter of the discharge port is Do, in order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm so that the discharge port is not clogged. In this way, a solution in which the upper limit of the size Dp is defined by Dp / Do ≦ 0.01 is used, and the ejection head ejects the droplets with an action force due to mechanical displacement of the piezo element and The flying shape is almost round or a column extending in the direction of flight, and the length is less than 3 times its diameter, and there is no minute drop behind the flying droplet. In this way, the droplet ejection manufacturing apparatus determines the drive waveform of the piezo element, and the pattern of electrodes connected to the pattern wiring or device formed by the droplet ejection manufacturing apparatus is a dot pattern based on the principle of droplet ejection Formed by a combination ofIn addition, the dot diameter is larger than the dot diameter of the pattern forming the pattern wiring or device.It is characterized by that.
[0023]
  Secondly,The ejection control is performed so that the ejection speed of the droplet is faster than the relative movement speed between the substrate and the ejection head..
[0024]
  Thirdly, in the liquid droplet jet manufacturing apparatus according to 1 or 2, the electrode pattern is formed by spraying a conductive fine particle-containing solution.It is formed.
[0025]
  Fourthly, in the liquid droplet ejection manufacturing apparatus according to any one of 1 to 3, the discharge port is made of a material harder than the fine particles in the fine particle-containing solution.It is an opening.
[0026]
  Fifth,On the electrode pattern formed on the substrate, andOn the substrate, by the ejection head whose discharge port diameter is Φ20μm or lessPiezo elementThe droplets of the solution containing fine particles are sprayed and applied by the action force due to mechanical displacement, the pattern is formed on the substrate and the electrode area, and the function manufactured by the droplet jet manufacturing equipment that forms the pattern wiring or device is given. In the patterned wiring board, the pattern is the patternDroplet flight, adhesionA pattern wiring board whose end is electrically connected to the electrode pattern on the substrate, and the electrode pattern isIt is formed by a combination of dot patterns based on the droplet ejection principle.
[0027]
  Sixthly, droplets of the fine particle-containing solution are jetted and applied on the electrode pattern formed on the substrate and on the substrate by an action force due to mechanical displacement of the piezo element by a jet head having a discharge port diameter of Φ20 μm or less, On the substrate and in the electrode regionDotIn a pattern wiring board provided with a function to be manufactured by a droplet jet manufacturing apparatus that forms a pattern and forms a pattern wiring or a device, the fine particles in the pattern have a size of Dp and the discharge port diameter of Do. In order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm, and the upper limit of the size Dp is set to Dp / Do so that the discharge port is not clogged. ≦ 0.01 is used, the pattern is formed by flying and adhering the droplet, and the end portion of the pattern wiring substrate is electrically connected to the electrode pattern on the substrate, The electrode pattern is formed by a combination of dot patterns based on the droplet ejection principleAnd the dot diameter is larger than the dot diameter of the pattern forming the pattern wiring.It is characterized by that.
[0028]
  Seventhly, in the patterned wiring board according to the fifth or sixth aspect, the electrode pattern is formed by spraying a conductive fine particle-containing solution.It is formed.
[0029]
Eighthly, in the patterned wiring board according to any one of the fifth to seventh aspects, the fine particles in the pattern are made of a material softer than a member constituting the discharge port.
[0030]
  Ninthly, droplets of the fine particle-containing solution are jetted and applied on the electrode pattern formed on the substrate and on the substrate by an action force due to mechanical displacement of the piezo element by an ejection head having an ejection port diameter of Φ20 μm or less, On the substrate and in the electrode regionDotIn a device substrate provided with a function to be manufactured by a droplet jet manufacturing apparatus that forms a pattern and forms a pattern wiring or a device, the pattern of the device is formed by the flying and adhering of the droplet, and its end portion is A device substrate electrically connected to the electrode pattern on the substrate, wherein the electrode pattern is formed by a combination of dot patterns based on a droplet ejection principleAnd the dot diameter is larger than the dot diameter of the device pattern.It is characterized by that.
[0031]
  Tenth, droplets of the fine particle-containing solution are jetted on the electrode pattern formed on the substrate as well as on the substrate with an action force due to mechanical displacement of the piezo element by a jet head having a discharge port diameter of Φ20 μm or less, On the substrate and in the electrode regionDotIn the device substrate provided with a function to be manufactured by a droplet jet manufacturing apparatus for forming a pattern and forming a pattern wiring or a device, the fine particles have a size of Dp and the discharge port diameter is Do. In order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm, and the upper limit of the size Dp is set to Dp / Do ≦ 0.01 so that the discharge port is not clogged. The device pattern is formed by flying and adhering the droplet, and the end portion of the device substrate is electrically connected to the electrode pattern on the substrate, and the electrode pattern Formed by a combination of dot patterns based on the droplet ejection principleAnd the dot diameter is larger than the dot diameter of the device pattern.It is characterized by that.
[0032]
  Eleventhly, in the device substrate according to the ninth or tenth aspect, the electrode pattern is formed by spraying a conductive fine particle-containing solution.It is formed.
[0033]
  Twelfth, in the device substrate according to any one of the ninth to eleventh aspects, the fine particles in the pattern are a material softer than a member constituting the discharge port.
  Furthermore, thirteenthly, droplets of the fine particle-containing solution are jetted and applied on the substrate by a jet head having a discharge port diameter of Φ20 μm or less to form a dot pattern, and the volatile components in the dot pattern after the volatilization are volatilized to obtain solid content. In a manufacturing method by droplet ejection that forms a pattern wiring or a device by remaining on the substrate, when the size of the fine particles is Dp and the discharge port diameter is Do, the fine particles are in a stable state in a solution. A lower limit of the size Dp is set to 0.0005 μm and the upper limit of the size Dp is defined as Dp / Do ≦ 0.01 so that the discharge port is not clogged. The ejection head ejects the droplets with an action force due to mechanical displacement of a piezo element, and the shape of the droplets when they fly is substantially round or in the flight direction. The drive waveform of the piezo element is determined so that it is a columnar shape and has a length within 3 times its diameter, and no minute droplets are behind the flying droplets, and ejection control is performed and connected to the dot pattern. The electrode pattern is also formed by a combination of dot patterns by similar droplet ejectionIn addition, the dot diameter is larger than the dot diameter of the pattern forming the pattern wiring or device.It is characterized by that.
  Furthermore, in the fourteenth aspect, in the manufacturing method using droplet ejection according to the thirteenth aspect, ejection control is performed so that the ejection speed of the droplet is faster than a relative movement speed between the substrate and the ejection head. And
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a droplet jet manufacturing apparatus according to the present invention will be described below. In addition, embodiment shown below is an illustration and is not limited to this.
FIG. 1 shows an example in which a pattern is formed by a technique of the present invention on a glass substrate, a plastic substrate, a semiconductor substrate such as Si, a glass / epoxy substrate, a flexible substrate, or the like. FIG. 1A shows a state where terminals are formed on such a substrate, and a dotted line portion in the figure is a region where a wiring pattern as described later is generated. FIG. 1B shows an example in which a wiring pattern is formed by jetting and drawing a solution containing fine conductive fine particles by the droplet jetting principle.
[0035]
Here, as a means for applying a solution containing fine conductive fine particles, an inkjet technique is applied in the present invention. The specific method will be described below.
FIG. 2 is a view for explaining an embodiment of a manufacturing apparatus for forming a patterned wiring board or a functional device of the present invention. In the figure, 11 is an ejection head unit (ejection head), 12 is a carriage, and 13 is a carriage. A substrate holder, 14 is a wiring board or a substrate for forming a functional device, 15 is a supply tube for a solution containing fine conductive fine particles, 16 is a signal supply cable, 17 is an ejection head control box (including a solution tank), Reference numeral 18 denotes an X-direction scan motor for the carriage 12, 19 denotes a Y-direction scan motor for the carriage 12, 20 denotes a computer, 21 denotes a control box, and 22 (22X1, 22Y1, 22X2, 22Y2) denotes 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 holder 13 and ejects a solution containing fine conductive fine particles.
[0036]
FIG. 3 is a schematic diagram showing the configuration of a droplet applying apparatus applied to the manufacture of a patterned wiring board or functional device formation of the present invention, and FIG. 4 is a main part of an ejection head unit of the droplet applying apparatus of FIG. It is a schematic block diagram.
The configuration of FIG. 3 is different from the configuration of FIG. 2 in that the substrate 14 side is moved to form a wiring pattern or a functional device on the substrate. 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 direction 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.
The droplet applying device (ejection head 33) of the discharge head unit 11 may be any mechanism as long as it can discharge a given amount of liquid droplets in particular. In particular, an ink jet capable of forming a droplet of about 0.1 pl to several hundreds pl. The principle mechanism is desirable.
[0037]
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. As in the disclosed method (Kyser method), an electrical signal is applied to the piezo-vibration element, this electrical signal is converted into mechanical vibration of the piezo-vibration element, and droplets are discharged from a fine nozzle according to the mechanical vibration. Is generally called a drop-on-demand system.
[0038]
As other methods, there are methods (Sweet method) disclosed in US Pat. No. 3,596,275, US Pat. No. 3,298,030, and the like. This generates a recording liquid droplet with a controlled charge amount by a continuous vibration generation method, and the generated charge amount controlled droplet flies between deflection electrodes to which a uniform electric field is applied. Thus, recording is performed on a recording member, which is usually called a continuous flow method or a charge control method.
[0039]
As another method, there is a method disclosed in Japanese Patent Publication No. 56-9429. This is a method in which bubbles are generated in a liquid, and droplets are ejected and ejected from fine nozzles by the action force of the bubbles, which is called a thermal ink jet method or a bubble jet (registered trademark) method.
There are a drop-on-demand method, a continuous flow method, a thermal ink jet method, and the like as a method for ejecting droplets as described above, and the method may be appropriately selected as necessary.
[0040]
In the present invention, in the manufacturing apparatus (FIG. 2) for forming such a patterned wiring board or functional device (functional element), the substrate 14 is determined by adjusting its holding position by the substrate positioning / holding means 22 of this apparatus. . Although simplified in FIG. 2, the substrate positioning / holding means 22 is brought into contact with each side of the substrate 14 and can be finely adjusted in the submicron order in the X direction and the Y direction orthogonal thereto. These are connected to the ejection head control box 17, the computer 20, the control box 21, etc., and the positioning information, fine adjustment displacement information, etc., the position information of the droplet application, the timing, etc. can be constantly fed back.
[0041]
Further, in the manufacturing apparatus for forming the pattern wiring board or the functional device of the present invention, in addition to the position adjusting mechanism in the X and Y directions, the rotating position adjusting mechanism is not shown (not visible because it is located under the substrate 14). have. In relation to this, the shape of the patterned wiring board or functional device forming substrate of the present invention and the arrangement of the functional device group to be formed will be described.
[0042]
The patterned wiring board or functional device forming substrate of the present invention is a glass substrate, a ceramic substrate, various plastic substrates including PET, a semiconductor substrate such as Si, a glass / epoxy substrate, a polyimide film, depending on the 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 pattern wiring substrates or functional devices that require weight reduction.
[0043]
The shape of various plastic substrates and polymer films used for the pattern wiring substrate or functional device forming substrate of the present invention is the functional device forming substrate that is economically produced, supplied, or finally manufactured. Because of its use, it is rectangular. That is, the two vertical and horizontal sides constituting the rectangular shape are substrates in which the two vertical sides are parallel to each other, the two horizontal sides are parallel to each other, and the vertical and horizontal sides form a right angle.
[0044]
In the present invention, the functional device groups to be formed are arranged in a matrix for such a substrate, and the two orthogonal directions of the matrix are parallel to the direction of the vertical side or the horizontal side of the substrate. The functional device group is arranged so that The reason why the functional device groups are arranged in a matrix and the reason why the vertical and horizontal sides of the substrate are parallel to two orthogonal directions of the matrix will be described below.
[0045]
As shown in FIG. 2 or FIG. 3, in the present invention, after the positional relationship between the substrate 14 and the solution ejection port surface of the discharge head unit 11 is first determined, the position control is not particularly performed. That is, the ejection head unit 11 ejects the solution while performing a relative movement in the X and Y directions parallel to the formation surface of the functional device group while maintaining a certain distance from the substrate 14. In other words, the X direction and the Y direction are two directions orthogonal to each other. When the substrate is positioned, the vertical direction or the horizontal side of the substrate is formed so as to be parallel to the Y direction or the X direction. Since the two functional device groups in the matrix arrangement are parallel to each other, a highly accurate device group can be formed only by a mechanism that performs ejection while performing relative movement. In other words, if a substrate shape, a matrix arrangement of functional device groups, and a relative movement device in two directions of X and Y orthogonal to each other as in the present invention are used, positioning of the substrate before droplet ejection for device formation is performed. If performed accurately, a highly accurate matrix arrangement of functional device groups can be obtained.
[0046]
Here, the description will be returned to the rotational position adjustment mechanism. As described above, in the present invention, the substrate is accurately positioned before the droplet ejection for device formation is performed, only the relative movement in the X and Y directions is performed, and other controls are not performed. It is intended to obtain a matrix-like arrangement. In this case, a problem is a shift in the rotation direction (the rotation direction with respect to the axis perpendicular to the plane determined by the two directions X and Y) when the substrate is first positioned.
[0047]
In order to correct this shift in the rotational direction, the present invention has a rotational position adjusting mechanism (not shown) that is not shown (not shown) as described above. Thus, when the displacement in the rotational direction is also corrected and the sides of the substrate are positioned, the apparatus of the present invention can obtain a highly accurate matrix arrangement of functional device groups by relative movement only in the X and Y directions.
[0048]
The rotation position adjustment mechanism has been described as a separate mechanism from 22 (22X1, 22Y1, 22X2, 22Y2) in the substrate positioning / holding means of FIG. 2 (not visible under the substrate 14). It is also possible to provide the substrate positioning / holding means 22 with a rotational position adjusting mechanism. For example, the substrate positioning / holding means 22 is brought into contact with the side of the substrate 14 so that the entire position of the substrate positioning / holding means 22 can be adjusted in the X direction or the Y direction. The angle adjustment is possible if two screws provided at a distance are moved independently at a portion that contacts the side of the substrate 14. This rotational position control information is also connected to the ejection head control box 17, the computer 20, the control box 21, etc. in the same manner as the positioning information and fine adjustment displacement information in the X and Y directions, and the droplet application position information, Timing, etc. can be constantly fed back.
[0049]
The above description is based on the premise that the substrate suitably used in the present invention is basically a rectangular shape, except that a semiconductor substrate such as Si is supplied as a round wafer, In that case, the substrate positioning / holding means 22 may be brought into contact with one straight side called an orientation flat (orientation flat) indicating the direction of the crystal orientation axis.
[0050]
Next, other means and configuration of positioning according to the present invention will be described. In the above description, the substrate positioning / holding means 22 is brought into 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. An example will be described in which strip-like patterns are provided in two directions orthogonal to each other on the substrate, not on the sides of the substrate 14. As described above, in the present invention, functional device groups are formed in a matrix on a substrate. Here, however, the above-described two orthogonal band-like patterns are defined as two orthogonal directions of the matrix. It forms so that it may become parallel. Such a pattern can be easily formed on a substrate by a photofabrication technique.
[0051]
The present invention is applied to the case of forming a wiring pattern as shown in FIG. 1 in addition to the case of forming a large number of functional device groups arranged in a matrix. It is formed in two orthogonal directions as in this example, and is formed so as to be parallel to the vertical and horizontal directions (X direction and Y direction) of the substrate, respectively. The wiring pattern may be formed as a pattern for the purpose of such positioning at a position that does not hinder the original function of the substrate of the present invention, or the element 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-direction belt-like patterns of the present invention. If such a belt-like pattern is provided, pattern detection can be performed by a detection optical system 32 using a CCD camera and a lens as will be described later with reference to FIG.
[0052]
Next, in the Z direction, which is a direction perpendicular to the X and Y directions, in the present invention, after the positional relationship between the substrate 14 and the solution ejection port surface of the discharge head unit 11 is first determined, There is no position control. In other words, the ejection head unit 11 ejects a solution containing fine conductive fine particles while performing a 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 for this is that if the control is performed at the time of jetting, not only the mechanism and the control system become complicated, but also the formation of the functional device by applying droplets to the substrate 14 becomes slow, and the productivity is significantly reduced. .
[0053]
Instead, in the present invention, the flatness of the substrate 14, the flatness of the device that holds the substrate 14, and the accuracy of the carriage mechanism that moves the discharge head unit 11 in the X and Y directions are improved. By doing so, the Z-direction control at the time of ejection is not performed, and 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, thereby improving the 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 application of the solution of the present invention is suppressed to 5 mm or less (the size of the substrate 14 is 100 mm × 100 mm or more). 4000mm x 4000mm or less).
[0054]
Although the apparatus is configured so that the plane determined by the two directions of the X and Y directions is normally maintained (horizontal to the vertical direction), the substrate 14 is small (for example, 500 mm × 500 mm or less). ) Does not necessarily need to be horizontal in the plane determined by the two directions of X and Y, and it is sufficient that the positional relationship of the arrangement of the substrates 14 is most efficient for the apparatus.
[0055]
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. The detection optical system 32 is close to the ejection head 33 that ejects the droplets 43. The droplets 43 are arranged so that the landing positions 44 of the droplets 43 coincide with each other.
[0056]
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.
[0057]
In FIG. 3, reference numeral 36 denotes an image identification mechanism for identifying image information captured by the previous detection optical system 32, and has a function of binarizing the contrast of the image and calculating the center of gravity position of the binarized specific contrast portion. I have it. Specifically, VX-4210, a high-precision image recognition device manufactured by Keyence Corporation can be used. A means for giving position information on the functional element substrate 14 to the image information obtained thereby is a position detection mechanism 38. For this purpose, a length measuring device such as a linear encoder provided in the XY direction scanning mechanism 37 can be used. The position correction control mechanism 39 corrects the position based on the image information and the position information on the functional element substrate 14, and this mechanism corrects the movement of the XY direction scanning mechanism 37. It is done. Further, the ejection head 33 is driven by the ejection head control / drive mechanism 40, and droplets are applied onto the functional element substrate 14. Each control mechanism described so far is centrally controlled by the control computer 35.
[0058]
Incidentally, FIG. 4 shows a diagram in which droplets are ejected obliquely onto the substrate surface. This is because the droplets fly obliquely in this manner in order to illustrate the detection optical system 32 and the ejection head 33 together. However, in actuality, spraying is performed so that it is substantially perpendicular to the substrate.
[0059]
In the above description, the ejection head unit 11 is fixed, and the functional element substrate 14 is moved to an arbitrary position by the XY direction scanning mechanism 37 so that the ejection head unit 11 and the functional element substrate 14 are moved relative to each other. Although realized, it is needless to say that the functional element substrate 14 may be fixed and the ejection head unit 11 may scan in the XY directions as shown in FIG. 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, and the discharge head unit 11 is orthogonal to X, Y It is better to adopt a configuration in which scanning is performed in the two directions, and droplet application of the solution is sequentially performed in the two orthogonal directions.
[0060]
When the substrate size is about 200 mm × 200 mm or less, the discharge head unit for applying droplets is a large array multi-nozzle type that can cover the range of 200 mm, and the relative movement between the discharge head unit and the substrate is orthogonal 2. It is possible to perform relative movement only in one direction (for example, only in the X direction) without performing in the direction (X direction, Y direction), and the mass productivity can be increased, but the substrate size is 200 mm × 200 mm. In the above case, it is difficult to realize a large array multi-nozzle type discharge head unit capable of covering such a range of 200 mm in terms of technology / cost. Scanning is performed in two directions of X and Y that are orthogonal to each other, and liquid droplet application is sequentially performed in these two orthogonal directions. It is better to have a configuration to do so.
[0061]
In particular, even when a final substrate smaller than 200 mm × 200 mm is manufactured, when a plurality of large substrates are manufactured, the original substrate is 400 mm × 400 mm- Since a 2000 mm × 2000 mm or larger one is used, the ejection head unit 11 scans in two orthogonal X and Y directions, and the application of the liquid droplets in the two orthogonal directions is performed. It is better to have a configuration in which they are performed sequentially.
[0062]
As the 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.
[0063]
In particular, when fine metal particles such as Au, Ag, and Cu are used, it is possible to form a fine circuit pattern that has low electrical resistance and is resistant to corrosion. In addition to such a circuit pattern, for example, a resistance element can be manufactured by using a solution containing fine particles of Pt or nichrome material, or Pd, Pt, Ru, Ag, Au, Ti, In, Metals such as Cu, Cr, Fe, Zn, Sn, Ta, W, Pb, PdO, SnO₂, In₂O_Three, PbO, Sb₂O_ThreeOxides such as HfB₂, ZrB₂, LaB₆, CeB₆, YB_Four, GdB_FourBy using a solution containing fine particles such as boride such as TiC, ZrC, HfC, carbide such as TaC, SiC and WC, nitride such as TiN, ZrN and HfN, semiconductor such as Si and Ge, and carbon. An electron-emitting device can be manufactured.
[0064]
In the present invention, the solution containing such fine conductive fine particles includes an aqueous solution and an oily solution.
An aqueous solution obtained by dispersing such fine conductive fine particles in a dispersion medium mainly composed of water can be prepared by the following method, for example.
That is, a water-soluble polymer is dissolved in an aqueous metal ion source solution such as chloroauric acid or silver nitrate, and an alkanolamine such as dimethylaminoethanol is added with stirring. Metal ions are reduced in several tens of seconds to several minutes, and metal fine particles having an average particle size of 0.5 μm (500 nm) or less are deposited. After removing chloride ions and nitrate ions by a method such as ultrafiltration, a concentrated conductive fine particle-containing solution can be obtained by concentration and drying. This conductive fine particle-containing solution can be stably dissolved and mixed in water, an alcohol solvent, a sol-gel process binder such as tetraethoxysilane or triethoxysilane.
[0065]
An oily 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 heterogeneous, 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 the aqueous system is obtained. This conductive fine particle-containing solution can be stably dissolved and mixed in aromatic solvents, ketone solvents, ester solvents and the like, polyesters, epoxy resins, acrylic resins, polyurethane resins, and the like.
[0066]
The concentration of the conductive fine particles in the dispersion medium of the conductive fine particle-containing solution can be a maximum of 80% by weight, but is appropriately diluted depending on the application.
Usually, the content of the conductive fine particles in the conductive fine particle-containing solution is 2 to 50% by weight, the content of the surfactant and the resin is 0.3 to 30% by weight, and the viscosity is 3 to 30 centipoise.
[0067]
In any material, the present invention performs pattern wiring formation or functional device formation by volatilizing a volatile component in a solution and leaving a solid content on a substrate. This solid material generates the function of each pattern or device, and the solvent (volatile component) is a vehicle for ejecting droplets by the ink jet principle.
[0068]
Other examples of the material of the droplet 43 include a group I-VII compound semiconductor such as CuCl, a group II-VI compound semiconductor such as CdS and CdSe, a group III-V compound semiconductor such as InAs, and a group IV semiconductor. Semiconductor crystal, TiO₂, SiO, SiO₂And a solution containing nanoparticles such as inorganic compounds such as metal oxides, phosphors, fullerenes and dendrimers, organic compounds such as phthalocyanines and azo compounds, and composite materials thereof.
[0069]
In the present invention, the target nanoparticles are usually fine particles having a particle size of 0.0005 to 0.2 μm (0.5 to 200 nm), preferably 0.0005 to 0.05 μm (0.5 to 50 nm). More strictly, it is determined in consideration of the dispersion stability of fine particles during production of the solution, the occurrence of clogging at the time of injection described later, and the surface roughness of the substrate on which the pattern is formed.
[0070]
The surface of these nanoparticles may be chemically or physically modified within the range not impairing the object of the present invention, and additives such as surfactants, dispersion stabilizers and antioxidants may be added. good. Such nanoparticles can be obtained by colloidal chemical methods such as reverse micelle method (Lianos, P. et al., Chem. Phys. Lett., 125, 299 (1986)) and hot soap method (Peng, X. et al , J. Am. Chem. Soc., 119, 7019 (1997)).
[0071]
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 (O / W emulsion) in which the continuous phase is an aqueous phase and the dispersed phase is an oil phase.
The aqueous phase is mainly water, but a water-soluble organic solvent may be added to water. Examples of water-soluble organic solvents include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200, # 400), glycerin, alkyl ethers of the glycols, N-methylpyrrolidone, 1,3- Examples thereof include dimethyl imidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethyl sulfoxide, diethanolamine, triethanolamine, ethanol, isopropanol and the like. The amount of water-soluble organic solvent used in the aqueous dispersion medium is usually preferably 30% by weight or less, and more preferably 20% by weight.
[0072]
The content of the nanoparticles in the dispersion varies depending on the desired film (layer) structure or particle arrangement structure and film (layer) thickness, but is usually in the range of 0.01 to 15% by weight with respect to 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 expressed sufficiently. Conversely, if the content is too large, the ejection stability at the time of ejecting droplets by the ink jet principle is impaired.
[0073]
In addition, the nanoparticle-containing solution that is preferably used in the present invention and ejected by the ink jet principle preferably contains a surfactant and a solvent for dispersing nanoparticles in the dispersion. Examples of the surfactant include an anionic surfactant (sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, sodium laurate, ammonium salt of polyoxyethylene alkyl ether sulfate, etc.), nonionic surfactant (polyoxyethylene alkyl). Ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl amines, polyoxyethylene alkyl amides, etc.), and these may be used alone or in combination of two or more. be able to.
[0074]
The amount of the surfactant is usually used in the range of 0.1 to 30% by weight with respect to the total weight of the solution, but more preferably in the range of 5 to 20% by weight. When the amount of the surfactant is less than this range, oil-water separation occurs in the aqueous dispersion, and there is a case where a uniform pattern cannot be coated by applying droplets. On the contrary, when the amount is more than this range, the viscosity of the aqueous dispersion medium tends to be too high.
[0075]
The solvent for dispersing the nanoparticles is usually a liquid such as toluene, hexane, pyridine, chloroform, and preferably volatile. The amount of the dispersing solvent is usually used in the range of about 0.1 to 20% by weight, but more preferably in the range of 1 to 10% by weight. If the amount of the dispersing solvent is less than this range, the amount of ultrafine particles that can be contained in the aqueous medium decreases. On the other hand, if it is more than this range, oil-water separation may occur in the aqueous dispersion medium.
[0076]
Furthermore, the organic compound can be dissolved in the dispersion. Examples of such organic compounds include trioctylphosphine oxide (TOPO), thiophenol, photochromic compounds (spiropyran, fulgide, etc.), charge transfer complexes, electron-accepting compounds, and the like that are solid at room temperature are preferable. . In this case, the amount of the organic compound in the dispersion is at least 1/10000, preferably about 1/1000 to 10 times the weight of the nanoparticles.
[0077]
As long as the object of the present invention is not impaired, additives such as surfactants, dispersion stabilizers, and antioxidants, or binders such as polymers and materials that gel during coating and drying are added to the suspension. Also good.
[0078]
A droplet containing such a nanoparticle-containing solution is 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, it may be first air-dried at −20 to 200 ° C., preferably about 0 to 100 ° C. for 1 hour or more, preferably 3 hours or more, and then dried under reduced pressure as necessary. good. The degree of decompression at this time is 1 × 10⁵It may be less than Pa, but preferably 1 × 10⁴It is about Pa or less, and the temperature is usually -20 to 200 ° C, preferably 0 to 100 ° C. The decompression time is about 1 to 24 hours.
[0079]
Although the thickness of the nanoparticle thin film obtained by said method is not specifically limited, Usually, the diameter of a nanoparticle is 1 mm, Preferably it is the diameter of a nanoparticle-about 100 micrometers. In the nanoparticle thin film, the nanoparticles are preferably present at a density of a certain level or more. In this sense, the average interparticle distance between individual nanoparticles in the nanoparticle aggregate is usually within 10 times the particle diameter, and more preferably within 2 times the particle diameter. If this average interparticle distance is too large, the nanoparticles will not exhibit collective function.
[0080]
Next, a liquid jet head suitably applied to the present invention will be described with reference to FIGS. This example is an example of 7 nozzles.
In this liquid ejecting head, a piezo element 46 is provided as an energy acting part in a flow path 45 into which a solution 56 is introduced. When a pulsed 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 discharged from 1. FIG. 5B shows a state in which the piezoelectric element 46 is no longer distorted and the volume of the flow path 45 is increased.
[0081]
Here, the solution 56 introduced into the flow path 45 immediately before the nozzle 1 has passed through the filter 57. In the present invention, the filter 57 is thus provided in the ejection head, and the filter removal function is provided in the vicinity of the nozzle 1. 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 so as not to cause deterioration in the performance of the pattern or device formed on the substrate. . Such a filter 57 can be incorporated into the ejection head 11 as shown in FIG. The ejection head 11 itself can also be made compact.
[0082]
As such a filter b57, for example, a stainless mesh filter is preferably used, and the pore diameter (filter mesh size) is set to 0.8 μm to 2 μm.
[0083]
Next, another example of the liquid ejecting 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 droplet jetting is the growth action force of film boiling bubbles generated instantaneously in a solution.
The liquid ejecting head shown here is of a type in which droplets are ejected from a short channel portion in which a solution flows, and is called an edge shooter type.
Here, an example in which the number of nozzles of the liquid ejecting head is four is shown. This liquid ejecting head is formed by bonding 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 application unit by a wafer process. It is comprised by forming the heat generating body 71 which is.
[0084]
On the other hand, the lid substrate 67 is provided with a groove 74 for forming a channel into which a solution containing a functional material is introduced, and a common liquid chamber for storing the solution introduced into the channel. A recess region 75 is formed, and the heat generating substrate 66 and the lid substrate 67 are joined as shown in FIG. 7 to form the flow path and the common liquid chamber. In the state where the heating element substrate 66 and the lid substrate 67 are joined, the heating element 71 is located on the bottom surface of the channel, and the solution introduced into these channels at the end of the channel. The nozzle 65 for ejecting a part of the nozzle as a droplet is formed. Here, the nozzle shape is rectangular, but it 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).
[0085]
In the present invention, a single functional element is formed by a plurality of droplets, or a pattern for forming a functional element or the like by a plurality of droplets is formed by overlapping or contacting dots. Therefore, when such a multi-nozzle type liquid jet head is used, a functional element can be formed very efficiently. In this example, a four-nozzle liquid ejecting head is shown, but the present invention is not necessarily limited to four nozzles. Needless to say, the larger the number of nozzles, the more efficiently the functional elements are formed. However, this is not simply a matter of increasing the number, and if it increases, the liquid jet head becomes expensive, and the probability of clogging of the jet nozzle increases. The balance of the production efficiency of the conductive element).
[0086]
FIG. 8 is a view of the multi-nozzle type liquid jet head manufactured as described above as viewed from the nozzle side. In the present invention, such a multi-nozzle type liquid jet head is provided for each solution to be jetted and mounted on a carriage as shown in FIG. FIG. 10 is a perspective view thereof.
[0087]
In FIGS. 9 and 10, the multi-nozzle type liquid jet heads are labeled A, B, C, and D, respectively, but each of the liquid jet heads A, B, C, and D has a nozzle portion of each liquid A different type of conductive fine particle-containing solution or nanoparticle-containing solution can be ejected for each liquid ejecting head while being configured separately for each ejecting head.
[0088]
In the present invention, a functional device is manufactured by spraying a conductive fine particle-containing solution or a nanoparticle-containing solution, but not only a single solution is sprayed, Since various types of solutions can be ejected, for example, a device structure in which a solution for forming an electrode pattern and a solution for forming a functional device are combined can be easily formed.
[0089]
Next, other features of the present invention will be described. As described above, the present invention performs pattern wiring formation or functional device formation, and the solution used for the formation is a nanoparticle-containing solution. The present invention also relates to a technique for forming a pattern on a substrate by ejecting the solution from a fine discharge port by a technique equivalent to the so-called inkjet ejection principle. However, in the ink used in the conventional ink jet 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.
Further, according to the present invention, a fine discharge port diameter, for example, a discharge port diameter of Φ20 μm or less (in terms of area, about 300 μm) is required due to a required pattern or device application.²The following must be used, and this clogging is a very serious problem.
[0090]
By the way, clogging is derived from the principle itself that a solution is ejected from a fine discharge port. That is, it occurs 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 can be called foreign matter in the solution.
[0091]
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 occurrence thereof. Specifically, a solution with a changed nanoparticle diameter was prepared, and after using a jet head with a known discharge port size, droplet ejection was performed for a certain period of time, then left for a certain period of time, and droplet ejection was resumed. The discharge port was checked for clogging. In that case, not only a complete blockage of the outlet, but also a partial clogging and a prior indication (a slight clogging) were considered as clogging and tested.
[0092]
The used ejection head uses a piezo element as shown in FIGS. 5 and 6 as a driving force for droplet ejection. That is, the mechanical displacement of the piezo element, which is an electro-mechanical conversion element, is taken as the displacement of the diaphragm of the liquid chamber, and droplets are ejected from the fine discharge port by the displacement acting force.
[0093]
Although not shown in the figure, an ejection head having a structure in which a nozzle plate in which nozzle holes are separately drilled is provided on one nozzle surface was used. In addition, the number of nozzles is also shown in a simplified example of seven nozzles, but actually, the number of nozzles (discharge ports) 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. The ejection heads were prepared from H1 to H4 (respective ejection port diameters were set to H1 = Φ20 μm, H2 = Φ15 μm, H3 = Φ10 μm, H4 = Φ5 μm). Further, the nozzle plate was formed by Ni electroforming, and the thickness of the discharge port portion was all 25 μm.
[0094]
The solution used was prepared as follows. That is, a water-soluble polymer was dissolved in silver nitrate, dimethylaminoethanol was added with stirring, and metal ions were reduced in 3 minutes to precipitate Ag fine particles having an average particle size of 0.5 μm (500 nm) or less. Thereafter, chlorine ions and nitrate ions were removed with an ultrafiltration membrane, and concentrated and dried to obtain a concentrated Ag fine particle-containing solution.
[0095]
Further, this Ag fine particle-containing solution was dissolved in acetone, alkanolamine was added while stirring, and Ag fine particles were dispersed in the polymer and precipitated on the oil phase side. This concentrated and dried concentrated Ag fine particle-containing solution was dissolved and mixed in a mixed solvent of water, alcohol and ethylene glycol to obtain a spray solution. In addition, in order to produce the solution which changed the magnitude | size of Ag microparticles | fine-particles, the centrifuge was used and the average particle diameter of Ag microparticles | fine-particles was prepared to 0.0001 micrometer-0.5 micrometer. However, those having an average particle size of 0.0003 μm or less were made, but could not be evaluated because they were not stable. The content of Ag fine particles in each solution was 10% by weight, and the resin content in the solution was 20% by weight. Moreover, the amount of ethylene glycol added was adjusted, and the viscosity of each solution was unified to 20 centipoise.
[0096]
In the test, each solution having different Ag fine particle diameters was combined with H1 to H4 having different discharge port diameters, and droplets were jetted continuously for 10 minutes, and then left for 10 hours in an atmosphere of 40 ° C. and 30% humidity. Then, the injection was resumed, and the occurrence of clogging was examined. The results are shown in Tables 1 to 4.
Table 1 shows head H1 (discharge port diameter Do = Φ20 μm), Table 2 shows head H2 (discharge port diameter Do = Φ15 μm), Table 3 shows head H3 (discharge port diameter Do = Φ10 μm), and Table 4 shows head H4. The case of (discharge port diameter Do = Φ5 μm) is shown. Judgment ○ indicates that it can be used practically well, Δ indicates that it can be used but is not very preferable, and X indicates that it is not practical at all.
[0097]
[Table 1]

[0098]
[Table 2]

[0099]
[Table 3]

[0100]
[Table 4]

[0101]
From the above results, when an ejection head having a discharge port diameter of Φ5 μm to Φ20 μm is used, there is no clogging if the Ag fine particle diameter Dp and the discharge port diameter Do satisfy the relationship of Dp / Do ≦ 0.01. It can be seen that stable droplet ejection can be obtained. Incidentally, although it is the lower limit value of Dp / Do, it is difficult for the Ag fine particle diameter Dp to be 0.0003 μm or less considering that such very fine particles are stably dispersed in the solution. Further, in order to stably eject droplets to all ejection heads having an ejection orifice diameter of Φ20 μm or less, the lower limit value of Dp / Do may be set to 0.0001 with a margin. That is, if the Ag fine particle diameter Dp and the ejection port diameter Do satisfy the relationship of 0.0001 ≦ Dp / Do ≦ 0.01, the pattern by droplet ejection using an ejection head having an ejection port diameter of Φ20 μm or less. It can be seen that a stable dispersion capable of forming or forming a device can be produced, and clogging of the discharge port (nozzle) can be prevented.
[0102]
In this experiment, a round discharge port (nozzle) was used. However, in the case of other shapes, the areas 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. This is almost equivalent to the Φ20 μm nozzle. In other words, the present invention has an area of approximately 300 μm.²An ejection head using the following nozzles, and its lower limit is approximately 20 μm²This is applied when a pattern is formed or a device is formed by spraying such a solution with a nozzle (with a discharge port diameter of Φ5 μm).
[0103]
In the experiment, an ejection head using a piezoelectric element as a driving force for droplet ejection was used. However, the ejection head used in the manufacturing apparatus of the present invention is not limited to this, and the electrostatic force between two electrodes is used. An electrostatic method that generates mechanical displacement of the diaphragm of the liquid chamber as a driving force can also be used satisfactorily. Since these impart mechanical action force to the liquid, there is an advantage that the liquid to be used is less restricted. Moreover, since this mechanical displacement can be displaced in an analog manner, the shape of the flying droplet can be made round by controlling the drive waveform. For example, in the present invention, the driving waveform is controlled to form flying droplets close to a round shape to obtain a good dot pattern, which will be described later.
[0104]
In addition, it is also possible to use a jet head that generates a film-boiling bubble instantaneously in the liquid by heat and uses the growth force of the bubble as a driving force for discharging the solution. Alternatively, a charge control method (continuous flow method) in which electric charges are applied to droplets that are continuously ejected and the droplets are deflected according to the amount of electric charges can be used.
[0105]
In addition, since the method of generating film boiling bubbles using a thermal head or the like uses heat, the solution to be used may be thermally deteriorated.
[0106]
On the other hand, the method of generating film boiling bubbles using a thermal head or the like allows high density and highly integrated arrangement of the heating element part and the discharge port part due to its structure, with an arrangement density of 600 dpi to 1200 dpi or more. Moreover, the number of discharge ports (nozzles) of 500 to 10000 can be easily realized, and is suitable for a manufacturing apparatus with high production efficiency.
[0107]
Next, other features of the present invention will be described. As described above, according to the present invention, a solution containing fine particles is made to stably eject a droplet from a minute discharge port without causing clogging. Here, after the droplet is ejected, the droplet adheres onto the substrate. The result of examining how to form a good pattern or device is shown.
[0108]
As described above, according to the present invention, the ejection head unit 11 performs pattern movement while maintaining a certain distance from the substrate 14 or performing relative movement in the X and Y directions parallel to the formation surface of the functional device group. Alternatively, a functional device group is formed. In other words, the ejection head unit 11 translates relative to the substrate surface with respect to the substrate 14, or the substrate 14 translates relative to the ejection head unit 11.
[0109]
At that time, each time the fine particle-containing solution for forming the pattern or the functional device group is ejected, if the relative movement is stopped and the ejection is performed, a highly accurate pattern or the functional device group can be formed. However, since the productivity is remarkably lowered, the solution is sequentially ejected without stopping the relative movement. In that case, the relative movement speed (for example, the X-direction movement speed of the carriage in FIG. 2) should not be determined simply by improving productivity, but also from the viewpoint of forming a highly accurate pattern or functional device group. Must be considered.
[0110]
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 ejected, it is necessary to make the ejection speed faster than the relative movement speed. In the case of forming a pattern or a functional device group by ejecting the fine particle-containing solution while performing relative movement in the X and Y directions while keeping the discharge head unit 11 at a certain distance from the substrate 14 as described above. The liquid droplets are deposited and formed on the substrate 14 at the speed of the combined vector of the relative speed and the jet speed. The positional accuracy is determined by appropriately selecting the ejection timing in consideration of the distance between the substrate 14 and the solution ejection port surface of the ejection head unit 11 and the speed of the combined vector. Can be attached.
[0111]
However, even if the target can be attached to the target position, if the relative speed is too high, the attached droplets flow on the substrate 14 by being dragged by the relative speed, and the pattern has a good shape. Or, a functional device group cannot be formed. The present invention has been examined in this regard. An example of the examination results is shown below. In this example, an apparatus as shown in FIG. 2 is used, and the X direction moving speed of the carriage 12 and the ejection speed of the ejection head unit 11 are changed, so that good droplet adhesion can be made on the substrate 14 and good pattern formation can be achieved. It was investigated whether it was possible.
[0112]
FIG. 11 shows an example of a pattern used for the test. Here, an Ag fine particle-containing solution was sprayed, and a wiring pattern was formed by connecting dot patterns of the solution between two rows of adjacent element electrodes (between ITO transparent electrodes), and the pattern formation status was evaluated. Is. Evaluation evaluated the pattern after formation under the microscope, and judged good / bad ((circle) / x). FIG. 11A is good (◯), and each dot pattern does not have a good round shape as shown in FIG. 11B, becomes an oval shape, and the landing position on the substrate is the original aim. Anything that deviates from the position of and touches the adjacent dot pattern is defective (x).
Further, this often occurs due to deterioration of the jetting performance due to the initial stage of clogging or generation of scratches on the discharge port, etc., but it is also defective (×) that micro droplets are scattered around.
[0113]
In addition to the evaluation of the shape, the resistance value between the upper and lower ITO transparent electrodes was measured to evaluate the resistance value fluctuation due to disconnection due to poor dot position accuracy or contact with adjacent (left and right) dots (○: Resistance value as intended, x: resistance value out of aim).
[0114]
Details of the experimental conditions are shown below. The substrate used is a glass substrate with an ITO transparent electrode, and the above Ag fine particle-containing solution (here, a fine particle diameter of 0.01 μm is used) is combined with the aforementioned H4 jet head (nozzle diameter Φ5 μm). 11 was formed. For simplicity, FIG. 11 shows a diagram in which a space between a pair of ITO transparent electrodes is filled with 4 dots. However, in actuality, dots of about Φ8 μm are arranged in about 1 row in the vertical direction. Approximately 1000 pieces are driven at a pitch of 4 μm, and the upper and lower ITO transparent electrodes (interelectrode distance 4 mm) are connected. In addition, a similar pattern is formed adjacent to the ITO transparent electrode and the ITO transparent electrode with a center-to-center distance of 12 μm.
[0115]
The used ejection head is an H4 ejection head having 64 nozzles (discharge ports) and an arrangement density of 100 dpi. The ejection head and the substrate move relative to each other (here, the substrate is fixed and the ejection head is scanned by carriage), the control is controlled in μ order, and the timing of ejection is controlled. In addition, pattern formation was performed while maintaining a center-to-center distance of 12 μm.
[0116]
The driving voltage for droplet ejection changes the input voltage to the piezo element from 14V to 21V in order to change the ejection speed. The driving frequency was 10 kHz. In an ejection head using such a piezo element, the ejection speed can be changed by changing the input voltage to the piezo element, but at the same time the mass of the ejection droplet also changes, so the drive waveform (rising waveform including striking and The falling waveform was controlled so that the volume of the ejected droplet was always almost constant (1 pl), and only the ejection speed was changed.
[0117]
In addition, the droplet shape at the time of droplet flight is separately ejected and observed under the same conditions as the element formation, and the shape is driven so as to become a substantially round droplet immediately before adhering to the substrate surface (3 mm in the present invention example). The waveform was controlled for injection (FIG. 12). Note that even if a rounded spherical shape is not obtained and the columnar shape extends in the flight direction, it can be easily reduced to a length within three times its diameter (l ≦ 3d) simply by controlling the drive waveform. (FIG. 13). At that time, a driving condition (driving waveform) that does not involve a plurality of minute droplets behind the flying droplet as described later (FIG. 14) was selected. The results are shown in Table 5 below.
[0118]
[Table 5]

[0119]
From the above results, it can be seen that when the carriage moving speed in the X direction is equal to or higher than the ejection speed, a good pattern cannot be formed, and the resistance value between the electrodes is not intended. In other words, when performing pattern wiring formation or functional device formation by applying droplets of a nanoparticle-containing solution onto a substrate with an apparatus using an ejection head using a piezo element and drying it as in the present invention, It can be seen that the velocity of the droplets ejected from the ejection head must be faster than the carriage movement speed in the X direction.
[0120]
Although this example is an example in which the ejection head is scanned by carriage, it is also applied to the case where the ejection head is fixed and the substrate is moved as shown in FIG. That is, the speed of the ejected droplets must be higher than the relative movement speed of the ejection head and the substrate.
[0121]
In addition, the droplet flight condition this time was set to a drive condition (drive waveform) that does not involve a plurality of minute droplets behind the droplet as described above (FIG. 14). As a result, the plurality of minute droplets never adhered to unnecessary portions, and a very good pattern formation could be performed.
[0122]
Further, even when the flying droplets are in the form of a column extending in the flying direction, the length of the flying droplets is set to be within 3 times the diameter (l ≦ 3d) by driving waveform control (FIG. 13). Therefore, the formed dots also have a shape close to a perfect circle, and a good pattern can be formed.
[0123]
Next, still another feature of the present invention will be described. The substrate or sheet to which the function of the present invention is imparted is a fine particle-containing solution obtained by dispersing innumerable fine particles and nanoparticles in the solution, flying in the air on the principle of ink jet, and forming droplets on the substrate or sheet. However, in order to produce a substrate or sheet with a high-precision and high-quality function, a fine particle-containing solution is sprayed and applied onto the substrate or sheet, and a fine structure is produced. It is necessary to optimize the surface roughness of the substrate or sheet and the size of the nanoparticles during pattern formation. For example, the surface roughness of the substrate or sheet is the unevenness of the surface, but as shown in FIG. 15, when particles of a size that protrudes from the unevenness adhere to the surface of the substrate or sheet, it is good. No pattern or device will be obtained. On the other hand, as shown in FIG. 16, if the particle has a size smaller than this unevenness, a good pattern or device will be obtained. In the present invention, in view of this point, a pattern is formed on a substrate whose surface roughness is known in advance using a solution containing fine particles having different sizes, and the quality of the formed pattern is evaluated.
[0124]
In the experiment, Pyrex (registered trademark) glass was polished to have a surface roughness of 0.01 s to 0.02 s, and the above Ag fine particle-containing solution (here, the fine particle diameter was adjusted) on the polished substrate. 0.0005 μm to 0.2 μm) is used in combination with the aforementioned H4 jet head (nozzle diameter Φ5 μm) to form a pattern in which dots are connected, and the smoothness of the pattern is observed under a microscope. Then, sensory evaluation was performed, and good to good to bad (◯ to Δ to x) were judged.
[0125]
Details of the experimental conditions are shown below. The pattern is one row in the vertical direction and about 100 dots of about Φ8 μm are implanted at a pitch of about 4 μm.
The used ejection head is an H4 ejection head having 64 nozzles (discharge ports) and an arrangement density of 100 dpi. The ejection head and the substrate move relative to each other (here, the substrate is fixed and the ejection head is scanned by carriage), the control is controlled in μ order, and the timing of ejection is controlled. As described above, dots are deposited at a pitch of about 4 μm. Went.
[0126]
As the driving voltage for droplet ejection, the input voltage to the piezo element was 15 V, and the driving frequency was 10 kHz. The volume of the spray droplet is always about 1 pl. Also, the droplet shape at the time of droplet flight is separately ejected and observed under the same conditions as pattern formation, and the drive waveform is such that the shape becomes a substantially round droplet immediately before adhering to the substrate surface (3 mm in the present invention example). Were controlled and jetted (FIG. 12). Note that even if a rounded spherical shape is not obtained and the columnar shape extends in the flight direction, it can be easily reduced to a length within three times its diameter (l ≦ 3d) simply by controlling the drive waveform. (FIG. 13). At that time, a driving condition (driving waveform) that does not involve a plurality of minute droplets behind the flying droplets as shown in FIG. 14 was selected.
[0127]
As described above, Ag fine particle-containing solutions having different fine particle diameters of 0.0005 μm to 0.2 μm were prepared and used (solution No. is common), but when the fine particle diameter is 0.02 μm or more. Since nozzle clogging started to occur, evaluation was performed by selecting only those patterns in which the clogging did not occur and the pattern was satisfactorily formed. The results are shown in Table 6 below.
[0128]
[Table 6]

[0129]
From the above results, it can be seen that the fine particles contained in the solution can form a smooth and favorable pattern by setting the size to be less than the surface roughness of the surface on which the pattern of the substrate is formed. On the other hand, when the size of the fine particles is larger than that, the smoothness of the pattern shape is impaired.
[0130]
In other words, in order to form a smooth and good pattern, the surface roughness of the surface on which the substrate pattern is formed may be made rougher than the size of the fine particles contained in the solution. However, since the fine particles used in the present invention are very fine nano-particles, the surface roughness of the substrate is visually in a mirror state, and it is necessary to polish the substrate with high accuracy. Alternatively, the surface of the substrate is SiO₂Even when using a substrate on which a thin film such as a thin film is formed, even when the thin film is formed (for example, formed by sputtering or the like), the surface has a smooth SiO 2₂In order to obtain a surface, it is necessary to perform film formation carefully over time. That is, the substrate manufacturing cost is high.
[0131]
By the way, considering that the pattern wiring board or functional device board of the present invention has a structure in which a pattern is formed on one side of the board as described above, only the board on which the pattern is formed is a smooth board. It can be seen that it should be used. That is, it is sufficient that only the surface of the substrate (surface on which the pattern is formed) has the surface roughness as described above and the back surface is rougher than that.
[0132]
In other words, in the present invention, a highly accurate pattern wiring board or functional device board can be obtained by using a substrate whose surface roughness on the back surface is rougher than the surface on which the pattern of the substrate is formed. Can be lowered. For example, the back surface roughness is made one digit rougher than the front surface (surface on which the pattern is formed) (for example, when the front surface is 0.01 s to 0.02 s, the back surface is 0.1 s to 0.2 s. The cost of manufacturing the board is greatly reduced. Furthermore, if the surface is roughened further, the cost will be substantially sufficient to make the front surface good, and the manufacturing cost can be reduced to nearly half that of a substrate polished on both the front and back surfaces with high precision. However, although it is the upper limit of the back surface roughness, it does not mean that any amount is required, and it is necessary to maintain a certain level of quality as an industrial product. This will be discussed below.
[0133]
As described above, according to the present invention, a pattern wiring board or a functional device board is manufactured by a manufacturing apparatus as shown in FIG. 2 (or FIG. 3). There is a problem at the time of manufacturing that the substrate cannot be moved due to 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 together. In short, the back surface of the substrate and the substrate holding surface in contact therewith are too smooth and difficult to remove.
In that case, the problem can be solved by setting the surface roughness of either surface (or both surfaces) to a rough state, but in the present invention, the back surface of the substrate is set to be equal to or less than the roughness of the substrate holding surface. The holding surface is made rougher.
[0134]
For one thing, it is necessary to maintain a certain level of quality as an industrial product for a pattern wiring board or a functional device board manufactured according to the present invention in consideration of subsequent usage. 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.
[0135]
The second reason is whether 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 or the like, but it is inevitable that the substrate holding surface is damaged during use and the surface becomes rough. If that is the case, it is better to keep this surface rougher without increasing the cost by smoothing the surface roughness from the beginning. The substrate holding surface formed by SUS304 or the like forms the surface by mechanical cutting, grinding, or scraping according to the surface roughness.
[0136]
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 used is quartz glass (size 100 mm × 100 mm), and the roughness of the back surface is 0.1 s to 0. In the case of 2 s, the roughness of the substrate holding surface made of SUS304 is 2 s to 5 s by cutting, the substrate to be used is a PET film (size 300 mm × 300 mm), and the roughness of the back surface is 0.5 s to 1 s. In this case, the substrate can be removed and replaced smoothly without the substrate sticking to the substrate holding surface. That is, when the roughness of the back surface of the substrate is set to be equal to or less than the roughness of the substrate holding surface, it is possible to avoid a manufacturing problem that the substrate cannot be moved (it is difficult to remove and replace the substrate). Became.
[0137]
Even when a plurality of minute suction holes are formed on the substrate holding surface of the substrate holder and the substrate is held by vacuum suction, the surface on which the suction holes are formed is It is considered that the surface roughness is roughened.
[0138]
Next, still another feature of the present invention will be described. FIG. 17 is an example of pattern wiring of a pattern wiring board formed according to the principle of the present invention. In this example, a wiring pattern is formed by spraying a fine particle-containing solution onto a terminal pattern (electrode pattern) formed by a rectangle or a combination of rectangles previously formed on a substrate. In this example, in order to avoid complication of the drawing, the wiring pattern dodds are arranged so that they are just in contact with each other in the adjacent oblique direction. The dots are arranged so that there are many overlapping portions of the dots), so that no uncovered portion is formed in the wiring pattern portion.
[0139]
FIG. 18 is an example of one device of a device substrate formed according to the principles of the present invention. This is an example in which a device is formed by spraying a fine particle-containing solution later onto a pair of element electrodes (electrode patterns) formed by a rectangle or a combination of rectangles previously formed on a substrate.
[0140]
However, there is one problem here. It is an abnormal discharge in a terminal pattern or element electrode (electrode pattern) portion that occurs when the circuit pattern or various devices are used after being used. This will be described with reference to FIGS.
[0141]
In the present invention, as shown in FIGS. 17 and 18, a wiring pattern is formed by a dot pattern of a solution containing a metal fine particle material between a plurality (two in this example) of terminal patterns (electrode patterns), or elements facing each other. Various electronic devices are formed with a dot pattern of a solution containing a metal fine particle material between electrodes. Usually, these terminal patterns and element electrodes (electrode patterns) are formed of a thin film such as Al, Au, Cu, or an ITO thin film. A desired pattern shape is formed by photolithography, etching, or the like. Usually, it is often composed of a rectangular pattern or a combination of rectangular patterns.
[0142]
This is a rectangular shape depending on the shape of the photomask when such an electrode pattern is formed by a photolithography technique (the rectangle is most easily manufactured in terms of cost). As shown in FIG. 18, since the corner portion of the electrode pattern is sharp, electric field concentration occurs at that portion. As a result, when applied between the two electrodes, there is a problem that abnormal electric discharge occurs in the electric field concentration portion and good device performance cannot be obtained.
[0143]
In the present invention, in view of this point, the corner portion of the electrode pattern is chamfered as shown in FIGS. 19 and 20, for example. In this example, c-shaped chamfering when displayed in a mechanical drawing is used, but it goes without saying that it may be r-shaped chamfering.
[0144]
Such a shape may be such that when the device electrode pattern is formed by photolithography, the shape of the photomask does not have such a sharp corner portion.
[0145]
The size of the chamfered portion is usually about 1/2 to 1/5 of the dot pattern diameter, that is, c2 μm to c5 μm, or r2 μm to r5 μm. can do.
[0146]
In the present invention, by eliminating the sharp part of the electrode pattern and eliminating the electric field concentration, there is no abnormal discharge when used as a circuit pattern or various devices, and it is stable even when used for a long time. The quality that you have come to get.
[0147]
Next, still another feature of the present invention will be described. 21 and 22 are equivalent to the wiring patterns or electronic devices described with reference to FIGS. In FIGS. 17 to 20, the electrode pattern is formed by forming a thin film of Al, Au, Cu or the like on the substrate in advance and making it into a desired pattern shape by photolithography, etching or the like. However, what is shown in FIGS. 21 and 22 is the electrode pattern formed by the solution injection principle of the present invention.
[0148]
That is, a solution containing fine particles of a conductive material such as Ag is used, and an electrode pattern is formed as a combination of dots in the same manner as the pattern wiring or device pattern formation as described above. The merit of doing in this way is that the problem of abnormal discharge described above can be solved in addition to the point that the manufacturing apparatus of the present invention described with reference to FIGS. As shown in FIGS. 21 and 22, if the electrode pattern is formed by a dot pattern by solution injection in which the metal fine particles of the present invention are dispersed, the dot pattern has a round shape and has a pointed portion. Since there is no, it can be automatically chamfered.
[0149]
21 and 22, the dot diameter of the electrode pattern portion is larger than the dot diameter of the wiring pattern portion or the device pattern portion, but this uses the same ejection head having the same discharge port diameter. Thus, the dot patterns may have the same size.
[0150]
Incidentally, the wiring pattern by the combination of dots shown in FIG. 17 is formed as a belt-like pattern extending in the longitudinal direction. Alternatively, in the device of FIG. 18, the dot pattern is formed as a belt-like pattern. The direction in which the pattern extends is the X direction or Y direction described with reference to FIGS. 2 to 4, that is, the relative movement direction between the substrate and the ejection head (the carriage movement direction in which the ejection head is mounted, or the substrate movement direction). By making them parallel, it is possible to simplify the pattern information for controlling the ejection of the solution and the control thereof, and it is possible to realize highly accurate pattern formation at a low cost.
[0151]
Similarly, these directions, that is, the direction in which the pattern is extended, are positioned by aligning the direction of each side of the rectangular substrate to be used or the direction of the matrix arrangement of the device group to be formed, or each pattern. Formation can be performed with high accuracy.
[0152]
Next, still another feature of the present invention will be described. The substrate or sheet to which the function of the present invention is imparted is a fine particle-containing solution obtained by dispersing innumerable fine particles and nanoparticles in the solution, flying in the air on the principle of ink jet, and forming droplets on the substrate or sheet. However, in order to stably produce a substrate or sheet with high-quality functions over a long period of time, the manufacturing equipment does not maintain stable and constant performance. must not. The most important point here is the long-term performance stability of the ejection head.
[0153]
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, but the fine particles are present like abrasive grains dispersed in the solution, and this solution is used in large quantities. In such a case, there is a problem that the passage of the solution of the jet head is damaged or worn. Among the passages, scratches and abrasion of the discharge port (nozzle) are particularly problematic because they affect the droplet ejection performance of the solution.
[0154]
By the way, such scratches and wear are caused when two objects collide with each other or rub against each other, and it is considered that they can be solved by appropriately selecting the hardness of each other. In addition, it is true that scratches affect the droplet jetting performance of the jet head, but how much the scratches are affected is considered to be determined by the size of the scratch and the size of the solution path. For example, even if a water discharge hose having an inner diameter of Φ15 mm to Φ20 mm has scratches on the order of nanometers, the water discharge flow rate cannot be greatly affected.
In the present invention, considering 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.
[0155]
The used ejection head is the same as the aforementioned H1 ejection head to H3 ejection head. That is, the piezoelectric element as shown in FIG. 5 and FIG. 6 is used as the driving force for droplet discharge, and the mechanical displacement of the piezoelectric element as an electro-mechanical conversion element is used as the displacement of the diaphragm of the liquid chamber. The liquid droplets are ejected from fine discharge ports.
[0156]
Although not shown in the figure, an ejection head having a structure in which a nozzle plate in which nozzle holes are separately drilled is provided on one nozzle surface is used. The number of nozzles is 64, and the arrangement density is 100 dpi.
[0157]
By using such an ejection head and performing solution ejection for a certain period of time, whether or not the ejection port (nozzle hole) is scratched and the pattern shape (dots) formed due to the deterioration of the solution droplet ejection performance Whether the shape of the pattern was good) and whether the pattern performance was deteriorated (resistance value change) were examined. Multi-nozzle plates were prepared with different materials and nozzle diameters (here rounded). Regarding the pattern performance, the difference in resistance between the pattern formed at the initial stage of injection and the pattern formed after performing the injection for a certain period of time was examined.
[0158]
The ejection head drive voltage was 20 V, the drive frequency was 10 kHz, and continuous ejection was performed for 100 hours. The ejection port portion after ejection was observed with an SEM to check for scratches.
The discharge port diameters were prepared with Φ20 μm (H1 jet head), Φ15 μm (H2 jet head), and Φ10 μm (H3 jet head), respectively.
[0159]
As a comparative reference example, one having a discharge port 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 ejection head drive voltage was 30 V, the drive frequency was 3.8 kHz, and continuous ejection was performed for 260 hours.
[0160]
The thickness of the nozzle plate was 30 μm for the H1 jet head and the H2 jet head, 20 μm for the H3 jet head, and 40 μm for the reference head. The speed of the droplets at the time of jetting was about 7 m / s in any jet head.
[0161]
The nozzle plate was made of Ni and austenitic stainless steel SUS304. A Ni nozzle made of a multi-nozzle plate by an electroforming method, and a stainless steel foil made of SUS304 was punched with a nozzle hole by electric discharge machining. When the hardness was measured with a Vickers hardness meter, the Vickers hardness Hv was 58 to 63 in the case of Ni material, and the Vickers hardness Hv was 170 to 190 in the case of SUS304 material.
[0162]
The liquid used is an aqueous solution in which fine particles are dispersed in a dispersion medium mainly composed of water as described above. The fine particles are the following seven types (S1 to S7). Table 7 shows the element names of the contained fine particles and the Vickers hardness Hv in the bulk state. In addition, this Vickers hardness Hv published the value of the metal data book (edited by the Japan Institute of Metals, revised 3rd 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.
[0163]
[Table 7]

[0164]
The results of evaluation using these sample solutions and the ejection head are shown in Tables 8 to 11 below. In the table, scratches ○ indicate that no conspicuous scratches could be confirmed after 100 hours of injection, and × indicates that a number of scratches that affect the nozzle shape or dimensions exist. A circle of the pattern shape is a dot pattern formed in a good round shape at a target position (between a pair of electrodes) when the pattern was produced after 100 hours of jetting (FIG. 11A). Is the one where the position is slightly off the target, the shape is irregular, or the micro droplets are scattered around (FIG. 11B). XX of the pattern performance is the difference in resistance value between the pattern formed at the initial stage of injection and the pattern formed after performing the injection for a certain period of time, and ○ is the resistance value when the pattern was prepared after 100 hours of injection. The pattern is almost the same as the pattern formed in (Practical level), and x is when the resistance value is abnormally large or short-circuited after 100 hours of spraying (Non-practical level). is there. In the case of the reference head, the ejection time is 260 hours.
[0165]
[Table 8]

[0166]
[Table 9]

[0167]
[Table 10]

[0168]
[Table 11]

[0169]
From the above results, it is understood that when the hardness of the contained fine particles is larger than that of the material of the discharge port (S3, S6), the discharge port is damaged. It can also be seen that the pattern shape formed thereby is poor and the pattern performance is also poor. Therefore, it can be seen that when such a pattern is formed by a manufacturing apparatus such as the present invention, it is necessary to select a material that is softer than the member that forms the discharge port for the fine particles. In other words, in the present invention, the member constituting the discharge port needs to be a material harder than the fine particles.
[0170]
Some of the scratches do not deteriorate the pattern shape because of the relationship with the size of the discharge port. Like the reference head, there is a diameter of Φ36μm (= area is about 1000μm)²In such a case, since the diameter of the discharge port is large even if there is a scratch, the pattern shape can be sufficiently used instead of a scratch that causes deterioration in the jetting performance. On the other hand, the discharge port diameter is Φ20 μm or less (= the area is about 300 μm)²In the case of 1/3 or less of the reference head in the area comparison as in the case of the following), even if scratches are similarly caused, the influence on the comparison with the discharge port diameter is large, and a good pattern shape It can be seen that the pattern performance cannot be obtained.
[0171]
In other words, if a very fine pattern is not formed, the problem of scratches does not affect the pattern performance, so there is no concern. In the case of spraying a solution containing fine particles having a fine particle diameter of 0.0005 μm to 0.2 μm and performing pattern formation, scratches on the discharge port are 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. In other words, the fine particles need to be made of a material that is softer than the member constituting the discharge port.
[0172]
In the experiment, a round Φ20 μm nozzle (area is about 314 μm)²), Φ15μm nozzle (area is about 177μm)²), Φ10μm nozzle (area is about 79μm)²) Is used, however, when nozzles of other shapes (for example, rectangles) are used as the nozzles of the ejection head, their areas may be compared. For example, a nozzle of 18 μm × 18 μm is a round shape of the present invention. This is equivalent to a Φ20 μm nozzle. In other words, the present invention has an area of about 300 μm.²The present invention is applied to the case where a pattern is formed by ejecting such a solution with an ejection head using the following nozzles.
[0173]
As is apparent from the above description, the present invention is a technique for manufacturing a pattern wiring board or a device board. However, a very fine pattern of several tens of μm to several μm is not formed by a conventional photolithography technique. A pattern and a device are directly manufactured by a simple apparatus in which droplets of a fine particle-containing solution are directly sprayed and applied to a substrate by a jet head having a micro discharge port that has not been conventionally available. Therefore, an expensive manufacturing apparatus used in a so-called semiconductor manufacturing process is not required, and it can be manufactured stably at a low cost.
[0174]
【The invention's effect】
As described above, according to the first aspect of the present invention, the droplet ejection for producing a pattern wiring substrate or a device substrate by ejecting a plurality of droplets of the fine particle-containing solution by the ejection head having a discharge port diameter of Φ20 μm or less. In the manufacturing equipment, the surface roughness of the surface on which the substrate pattern is formed is made larger than the size of the fine particles. In other words, the size of the fine particles is finer than the surface roughness of the substrate. did. Further, the surface roughness of the back surface of the substrate is made rougher than the surface roughness of the surface on which the pattern is formed, thereby realizing cost reduction of the substrate. Furthermore, by optimizing the size and discharge port size of the fine particles, realizing stable ejection without clogging, and ejecting liquid droplets with the force of mechanical displacement, ejecting liquid droplets that are easy to form good dots Thus, a good dot pattern can be formed. In addition, this pattern is formed by a dot pattern of a solution, and its end is electrically connected to the electrode pattern on the substrate to form a pattern wiring board or device substrate. Because the part is chamfered, a high-quality, reliable, and highly accurate pattern wiring board or device board that does not cause abnormal discharge can be manufactured stably and at low cost using a new method. It was.
[0175]
According to the second aspect of the present invention, in a droplet jet manufacturing apparatus for manufacturing a pattern wiring board or a device substrate by applying a plurality of droplets of a fine particle-containing solution by a jet head having a discharge port diameter of Φ20 μm or less. The surface roughness of the surface on which the pattern was formed was made rougher 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, so that highly accurate pattern formation was realized. Further, the surface roughness of the back surface of the substrate is made rougher than the surface roughness of the surface on which the pattern is formed, thereby realizing cost reduction of the substrate. In addition, the size of the fine particles and the discharge port diameter are optimized to achieve stable ejection without clogging, while droplets are ejected by the force of mechanical displacement, and the flight distance is shortened. Since the jetting speed of this was made faster than the relative movement speed of the substrate and the jetting head, a good dot pattern could be formed. Furthermore, this pattern is formed by a dot pattern of a solution, and its end is electrically connected to the electrode pattern on the substrate to form a pattern wiring board or device substrate. Because the part is chamfered, a high-quality, reliable, and highly accurate pattern wiring board or device board that does not cause abnormal discharge can be manufactured stably and at low cost using a new method. It was.
[0176]
According to the third aspect of the present invention, in such a droplet jet manufacturing apparatus, the electrode pattern is formed by a combination of dot patterns formed by spraying and applying a conductive fine particle-containing solution. Because the corners of the electrode pattern can be rounded instead of pointed, a high-quality, highly reliable and highly accurate pattern wiring board or device board that does not cause abnormal discharge can be produced at low cost using a new method. And now it can be manufactured stably.
[0177]
According to the invention described in claim 4, in such a droplet jet manufacturing apparatus, since the discharge port of the jet head is an opening formed in a substrate made of a material harder than the fine particles in the fine particle-containing solution, it can be used for a long time. Even if the discharge port is not scratched or damaged, a high-quality pattern wiring board or device board can be manufactured stably over a long period of time.
[0178]
According to the fifth aspect of the present invention, in the pattern wiring board manufactured by such a droplet jet manufacturing apparatus, the surface roughness of the surface on which the substrate pattern is formed is made larger than the size of the fine particles. For example, since the size of the fine particles is 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 rougher than the surface roughness of the surface on which the pattern is formed, thereby realizing cost reduction of the substrate. Furthermore, this pattern is formed by a dot pattern of a solution, and its end is electrically connected to the electrode pattern on the substrate to form a pattern wiring board. This electrode pattern has a corner portion with a chamfered shape. Therefore, it has become possible to obtain a high-quality, highly reliable, and highly accurate pattern wiring board that does not cause abnormal discharge.
[0179]
According to the invention described in claim 6, in the patterned wiring board manufactured by such a droplet jet manufacturing apparatus, the surface roughness of the surface on which the substrate pattern is formed is made larger than the size of the fine particles. For example, since the size of the fine particles is 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 rougher than the surface roughness of the surface on which the pattern is formed, thereby realizing cost reduction of the substrate. Furthermore, since the size of the fine particles and the discharge port diameter are optimized, it can be manufactured by stable injection without clogging, and high-precision pattern formation is realized. In addition, this pattern is formed by a dot pattern of a solution, and its end portion is electrically connected to the electrode pattern on the substrate to form a pattern wiring board. This electrode pattern has a corner portion with a chamfered shape. Therefore, it has become possible to obtain a high-quality, highly reliable, and highly accurate pattern wiring board that does not cause abnormal discharge.
[0180]
According to the invention of claim 7, in the pattern wiring board manufactured by such a droplet jet manufacturing apparatus, the electrode pattern is a combination of dot patterns formed by spraying and applying a conductive fine particle-containing solution. As a result, the corners of the electrode pattern can be formed round, not sharp, and a high-quality, reliable, and accurate pattern wiring board that does not cause abnormal discharge can be obtained. It was.
[0181]
According to the invention described in claim 8, in the pattern wiring board manufactured by such a droplet jet manufacturing apparatus, the fine particles in the pattern are made of a material softer than the member constituting the discharge port of the jet head. Even if the manufacturing apparatus is used for a long period of time, the discharge port is not scratched or damaged, and a high-quality pattern wiring board can be obtained.
[0182]
According to the ninth aspect of the present invention, in the device substrate manufactured by such a droplet jet manufacturing apparatus, the surface roughness of the surface on which the device of the substrate is formed is rougher than the size of the fine particles. Since the size of the fine particles is finer than the surface roughness of the substrate, highly accurate device pattern formation was realized. In addition, the substrate has a lower surface roughness than the surface on which the device is formed, thereby reducing the cost of the substrate. Furthermore, this device pattern is formed by a dot pattern of a solution, and its end portion is electrically connected to the electrode pattern on the substrate to form a device substrate. This electrode pattern has a corner portion with a chamfered shape. As a result, it has become possible to obtain a high-quality, highly reliable and highly accurate device substrate that does not cause abnormal discharge.
[0183]
According to the invention described in claim 10, in the device substrate manufactured by such a droplet jet manufacturing apparatus, the surface roughness of the surface on which the device of the substrate is formed is rougher than the size of the fine particles. Since the size of the fine particles is finer than the surface roughness of the substrate, highly accurate device pattern formation was realized. In addition, the substrate has a lower surface roughness than the surface on which the device is formed, thereby reducing the cost of the substrate. Furthermore, since the size of the fine particles and the discharge port diameter are optimized, it can be manufactured by stable injection without clogging, and a highly accurate device pattern can be formed. In addition, this device pattern is formed by a dot pattern of a solution, and an end portion thereof is electrically connected to the electrode pattern on the substrate to form a device substrate. This electrode pattern has a corner portion with a chamfered shape. As a result, it has become possible to obtain a high-quality, highly reliable and highly accurate device substrate that does not cause abnormal discharge.
[0184]
According to the eleventh aspect of the present invention, in the device substrate manufactured by such a droplet jet manufacturing apparatus, the electrode pattern is a combination of dot patterns formed by spraying the conductive fine particle-containing solution. Since it is formed, the corner portion of the electrode pattern can be formed in a round shape instead of a pointed shape, and a high-quality, highly reliable and highly accurate device substrate free from abnormal discharge can be obtained.
[0185]
According to the twelfth aspect of the present invention, in the device substrate manufactured by such a droplet jet manufacturing apparatus, the fine particles in the device pattern are made of a material softer than the member constituting the discharge port of the jet head. Even when the manufacturing apparatus is used for a long period of time, the discharge port is not scratched or damaged, and a high-quality device substrate can be obtained.
[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 patterned wiring board 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 patterned wiring board or a device substrate according to the present invention.
FIG. 4 is a schematic configuration diagram showing a droplet applying apparatus applied to manufacture of a patterned wiring board or a device substrate according to the present invention.
FIG. 5 is a diagram for explaining a droplet ejection principle of an ejection head using a piezoelectric element that is preferably used in the present invention.
FIG. 6 is a diagram showing the structure of a jet head using a piezoelectric element that is preferably used in the present invention.
FIG. 7 is an example of a thermal type (bubble type) liquid jet head suitably applied to the present invention.
FIG. 8 is a diagram of a multi-nozzle type liquid jet head viewed from the nozzle side.
FIG. 9 is a diagram in which a multi-nozzle type liquid jet head is stacked for each solution to be jetted and unitized.
FIG. 10 is a perspective view of the head unitized as shown in FIG.
FIG. 11 is a diagram showing an example of a test pattern used to find a condition for forming a favorable pattern by the droplet jet manufacturing apparatus of the present invention.
FIG. 12 is a diagram for explaining an example of a droplet flying shape when ejected by an action force due to mechanical displacement by an ejection head used in the droplet ejection manufacturing apparatus of the present invention.
FIG. 13 is a diagram for explaining another example of the droplet flying shape when ejected by the acting force due to mechanical displacement by the ejection head used in the droplet ejection manufacturing apparatus of the present invention.
FIG. 14 is a diagram for explaining an example of a droplet flying shape when ejected by an action force of a film boiling bubble.
FIG. 15 is a diagram schematically showing the relationship between fine particles and surface roughness when a dot pattern is formed with a solution containing fine particles larger than the surface roughness of the substrate.
FIG. 16 is a diagram schematically showing the relationship between fine particles and surface roughness when a dot pattern is formed with 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 forming a pattern wiring by combining droplets or solution dots in accordance with the principle of the present invention.
FIG. 18 is a diagram for explaining an example of forming a device by combining droplets or solution dots according to the principle of the present invention.
FIG. 19 is an example in which abnormal discharge at a corner portion is improved in the example of FIG.
20 is an example in which abnormal discharge at a corner portion is improved in the example of FIG.
FIG. 21 is another example in which the abnormal discharge in the corner portion is improved in the example of FIG.
22 is another example in which the abnormal discharge at the corner portion is improved in the example of FIG.
[Explanation of symbols]
1 (Liquid jet head) nozzle
11 Discharge head unit (jet head)
12 Carriage
13 Substrate holder
14 Substrate
15 Supply tube for fine particle-containing solution
16 Signal supply cable
17, 21 Control box
18 X-direction scan motor
19 Y-direction scan motor
20 computers
22 Substrate positioning / holding means
31 Head alignment control mechanism
32 Detection optical system
33 Injection head
34 Head alignment fine adjustment mechanism
36 Image recognition mechanism
37 XY direction scanning mechanism
38 Position detection mechanism
39 Position correction control mechanism
40 Ejection head drive / control mechanism
41 optical axis
42 Device electrodes
43 droplets
44 Droplet landing position
45 flow path
46 Piezo elements
56 solutions
57 Filter
65 nozzles
66 Heating element substrate
67 Lid substrate
68 Silicon substrate
69 Individual electrode
70 Common electrode
71 Heating element
74 Groove
75 recessed area
76 Solution inlet

Claims (14)

After applying the droplets of the fine particle-containing solution on the electrode pattern formed on the substrate and on the substrate, the droplets of the fine particle-containing solution are ejected by the ejection head having a discharge port diameter of Φ20 μm or less, and the dot pattern is formed on the substrate and the electrode region. In the droplet jet manufacturing apparatus for forming a pattern wiring or device by volatilizing the volatile component in the droplet pattern and leaving the solid content on the substrate and the electrode region, the size of the fine particles is Dp, When the discharge port diameter is Do, in order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm, and the size Dp is set so that the discharge port is not clogged. A solution having an upper limit defined by Dp / Do ≦ 0.01 is used, and the ejection head ejects the droplets with an action force due to mechanical displacement of a piezo element. In addition, the shape of the droplet when flying is almost a round droplet or a columnar shape extending in the flying direction and has a length within three times its diameter, and accompanied by a minute droplet behind the flying droplet. A droplet ejection manufacturing apparatus in which the drive waveform of the piezo element is determined so that the pattern wiring formed by the droplet ejection manufacturing apparatus or the pattern of the electrodes connected to the device is a dot based on the droplet ejection principle A droplet jet manufacturing apparatus characterized by being formed by a combination of patterns and having a dot diameter larger than a dot diameter of a pattern forming the pattern wiring or device .   2. The droplet ejection manufacturing apparatus according to claim 1, wherein ejection control is performed so that an ejection speed of the droplet is faster than a relative movement speed between the substrate and the ejection head.   The droplet jet manufacturing apparatus according to claim 1, wherein the electrode pattern is formed by spraying and applying a conductive fine particle-containing solution.   The droplet ejection manufacturing apparatus according to any one of claims 1 to 3, wherein the discharge port is an opening made of a material harder than the fine particles in the fine particle-containing solution. The droplets of the fine particle-containing solution are sprayed and applied on the electrode pattern formed on the substrate and on the substrate by an action force due to mechanical displacement of the piezo element by an ejection head having a discharge port diameter of Φ20 μm or less. In a pattern wiring board to which a dot pattern is formed in a region and a function to be manufactured by a droplet jet manufacturing apparatus for forming a pattern wiring or a device is given, the pattern is formed by flying and adhesion of the droplet, The pattern wiring board is electrically connected to the electrode pattern on the substrate, and the electrode pattern is formed by a combination of dot patterns based on the droplet ejection principle , and the dot diameter is formed by the pattern wiring. A pattern wiring board characterized in that it is larger than the dot diameter of the pattern to be printed. The droplets of the fine particle-containing solution are sprayed and applied on the electrode pattern formed on the substrate and on the substrate by an action force due to mechanical displacement of the piezo element by an ejection head having a discharge port diameter of Φ20 μm or less. In a pattern wiring substrate to which a dot pattern is formed in a region and a function to be manufactured by a droplet jet manufacturing apparatus that forms a pattern wiring or a device is given, the fine particles in the pattern have a size of Dp and the discharge port diameter In order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm, and the upper limit of the size Dp is set so as not to clog the discharge port. A solution defined by Dp / Do ≦ 0.01 is used, and the pattern is formed by the flying and adhesion of the droplet, A pattern wiring board that is electrically connected to an electrode pattern on a substrate, wherein the electrode pattern is formed by a combination of dot patterns based on a droplet ejection principle , and the dot diameter of the pattern that forms the pattern wiring A patterned wiring board characterized by being larger than the diameter .   The pattern wiring board according to claim 5, wherein the electrode pattern is formed by spraying a conductive fine particle-containing solution.   The pattern wiring board according to claim 5, wherein the fine particles in the pattern are made of a material that is softer than a member constituting the discharge port. The droplets of the fine particle-containing solution are sprayed and applied on the electrode pattern formed on the substrate and on the substrate by an action force due to mechanical displacement of the piezo element by an ejection head having a discharge port diameter of Φ20 μm or less. In a device substrate provided with a function to be manufactured by a droplet jet manufacturing apparatus that forms a dot pattern in a region and forms a pattern wiring or a device, the pattern of the device is formed by the flight and adhesion of the droplet, An end portion is a device substrate electrically connected to the electrode pattern on the substrate, and the electrode pattern is formed by a combination of dot patterns based on a droplet ejection principle , and the dot diameter is set to the pattern of the device. A device substrate characterized by being larger than the dot diameter . The droplets of the fine particle-containing solution are ejected and applied on the electrode pattern formed on the substrate and on the substrate by an ejecting head having a discharge port diameter of Φ20 μm or less by an action force due to mechanical displacement of the piezoelectric element. In a device substrate provided with a function to be manufactured by a droplet jet manufacturing apparatus that forms a dot pattern in a region and forms a pattern wiring or a device, the fine particles have a size of Dp and a discharge port diameter of Do. In order to disperse the fine particles in the solution in a stable state, the lower limit of the size Dp is set to 0.0005 μm, and the upper limit of the size Dp is set to Dp / Do ≦ 5 so that the discharge port is not clogged. The solution defined in 0.01 is used, and the pattern of the device is formed by the flying and adhesion of the droplet, and the end portion is formed on the substrate. A device substrate electrically connected to the electrode pattern, wherein the electrode pattern is formed by a combination of dot patterns based on a droplet ejection principle , and the dot diameter is made larger than the dot diameter of the device pattern. A featured device substrate.   The device wiring board according to claim 9 or 10, wherein the electrode pattern is formed by spraying and applying a conductive fine particle-containing solution.   The device substrate according to any one of claims 9 to 11, wherein the fine particles in the pattern are made of a material softer than a member constituting the discharge port. On the substrate, droplets of the fine particle-containing solution are sprayed and applied by a jet head having a discharge port diameter of Φ20 μm or less to form a dot pattern, volatilizing the volatile components in the dot pattern after application, and solid content on the substrate In a manufacturing method by droplet ejection in which pattern wiring or a device is formed by remaining, when the size of the fine particles is Dp and the discharge port diameter is Do, in order to disperse the fine particles in a solution in a stable state The lower limit of the size Dp is set to 0.0005 μm, and a solution in which the upper limit of the size Dp is defined as Dp / Do ≦ 0.01 so that the discharge port is not clogged is used. The droplet is ejected by an action force due to the mechanical displacement of the piezo element, and the shape of the droplet at the time of flight is a substantially round droplet or a columnar shape extending in the flight direction. The drive waveform of the piezo element is determined so that the length is within 3 times the diameter and no micro-droplet is behind the flying droplet, and ejection control is performed, and the electrode pattern connected to the dot pattern is the same A method of manufacturing by droplet ejection , wherein the dot diameter is larger than the dot diameter of the pattern forming the pattern wiring or device .   14. The manufacturing method by droplet ejection according to claim 13, wherein ejection control of the droplet is controlled so as to be faster than a relative movement speed between the substrate and the ejection head.

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