JP2004277780A - Layered structure of silver alloy, and electrode, electric wiring, reflective film and reflective electrode using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layered structure of a silver alloy having more excellent properties in low electrical resistance, weathering resistance, heat resistance, workability, adhesiveness and high reflectance than predetermined levels, and to provide an electrode, electric wiring, a reflective film and a reflective electrode using it. <P>SOLUTION: The layered structure of the silver alloy comprises a bottom thin film of a silver alloy containing primarily silver and at least one element having a negative standard electrode potential as secondary or higher components, formed on a substrate; and the top thin film of a silver alloy containing primarily silver and only the metals having a positive standard electrode potential as secondary or higher components, formed on the bottom thin film so as to be thinner than the bottom thin film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【表２】

【表３】

【００２９】
下部銀系合金薄膜の組成としては、ＡｇＺｎＰｄＣｕ、ＡｇＮｄＣｕ、ＡｇＮｄ、ＡｇＺｎＣｕ，ＡｇＳｎＣｕ，ＡｇＩｎＣｕ，Ａｇ−Ｍｇ系、Ａｇ−Ｌｉ系、ＡｇＺｎ、ＡｇＺｎＣｕ、，ＡｇＺｎＰｄＣｕ、ＡｇＮｄ、ＡｇＮｄＣｕ、ＡｇＮｄＰｄ、ＡｇＮｄＭｇ、ＡｇＮｄＴｉ、ＡｇＮｄＴｅ、ＡｇＮｄＡｕ、ＡｇＮｄＣｕＡｕ、ＡｇＮｄＣｕＰｄ、ＡｇＳｎ、ＡｇＳｎＣｕ、ＡｇＩｎ、ＡｇＩｎＣｕ、ＡｇＴｉ、ＡｇＴｉＣｕ、ＡｇＡｌ、ＡｇＡｌＣｕ、ＡｇＧｅ、ＡｇＧｅＣｕ、ＡｇＭｇ、ＡｇＭｇＣｕ、ＡｇＭｇＰｄ、ＡｇＭｇＰｄＣｕ、ＡｇＮｉ、ＡｇＮｉＣｕ、ＡｇＴａ、ＡｇＴａＣｕ、ＡｇＹ，ＡｇＹＣｕ、ＡｇＧａ、ＡｇＧａＣｕ、ＡｇＣ、ＡｇＮｂ、ＡｇＮｂＣｕ、ＡｇＰｄＡｌ、ＡｇＰｄＣｕＡｌ、ＡｇＺｎＰｄＡｌＣｕ、ＡｇＬｉ、ＡｇＬｉＣｕ、ＡｇＬｉＰｄ、ＡｇＬｉＰｄＣｕ、ＡｇＬｉＭｇ、ＡｇＬｉＭｇＣｕ、ＡｇＩＴＯ、ＡｇＳｎＯ２、ＡｇＩｎＯ２、ＡｇＺｎＯを例示できる。下部銀系合金薄膜の組成は、表４に例示した。
【表４】

【００３０】
上部銀系合金薄膜は、銀を主成分とし第２成分以下に標準電極電位が正である金属のみを含有する銀系合金である。標準電極電位が正である金属は、Ｃｕ、Ｒｕ、Ｒｈ、Ｐｄ、Ｒｅ、Ｏｓ、Ｉｒ、Ｐｔ、Ａｕである。上部銀系合金薄膜の組成としては、ＡｇＰｄＣｕをはじめとして表５〜表７に示したものが例示できる。表５〜表７の中で「○」はその金属を含有するとの意味である。
【表５】

【表６】

【表７】

【００３１】
上部銀系合金薄膜を下部銀系合金薄膜よりも薄く形成する。この理由は、上部銀系合金薄膜は一種の保護膜として機能させ、耐熱性は主として下部銀系薄膜で確保するためである。上部銀系合金薄膜は１０ｎｍ（１００Å）以上であることが好ましい。１０ｎｍ未満であると、保護膜としての機能が低下し、下部銀系薄膜の耐湿性を確保できなくなるからである。
【００３２】
反射膜の反射率低下は、主に以下の２つの理由から引き起こされる。
▲１▼加熱プロセスによる反射膜の結晶成長とヒロック発生による乱反射。これは結晶成長のし易さ、つまり耐熱性に起因する。
▲２▼放置時に大気中の物質と反射膜が化学反応、酸化、水酸化などを起こすことによる表面の変質。これは、耐候性に起因する。
【００３３】
以後、本発明であるＡｇ合金について記述する。
▲１▼の材料的な改善方法として、Ａｇの結晶成長を抑制する効果の高い元素を添加する。Ａｇの結晶成長を抑制する元素としては、標準電極電位が正な元素よりも、負である元素の方が効果が高い。▲２▼の材料的な改善方法として、標準電極電位が正である様な化学的に安定である元素を添加する。上記から▲１▼の改善方法と▲２▼の改善方法が矛盾する。つまり、材料設計の際にトレードオフとなり、１つの材料としての改善は、耐熱性と耐候性がバランスする性能を超えた高いレベルでの両立が困難であることを意味する。本技術は、耐熱性と耐候性を一材料として高いレベルで改善しようとする物ではなく、耐熱性に特化した材料と、耐候性に特化した材料の２つを組み合わせることで、双方の長所を生かし短所を補う技術である。
【００３４】
下部の層には耐熱性の高いＡｇ合金を設け、高い耐熱性を得ることを目的とする。さらにその上部に耐候性の高いＡｇ合金を設け、下部のＡｇ合金が変質する事を防ぐことを目的とする少なくとも２層以上である積層構造である。この技術は、下部の層と上部の層の双方の両方の長所を生かし短所を補うＡｇ合金積層体を提供しようというものであるから、下部と上部に組み合わせる材料は、耐熱性に特化した物と耐候性に特化した物以外の組み合わせとすることが可能である。例えば、下部にエッチング性に特化した材料、上部に反射率に特化した材料を組み合わせることで、良好なエッチング性と高反射率を兼ね備えた積層体として用いることができる。他にも、下部に低抵抗に特化した材料、上部に耐候性に特化した材料を組み合わせることで、低抵抗と高耐候性を兼ね備えた積層体として用いることができる。これらの応用により反射板、電極、配線、反射電極、反射配線、半導体素子など様々な用途への使用が可能である。
【００３５】
図２に別形態の銀系合金の積層構造を示した。図２に示した銀系合金の積層構造は、基板上に金属若しくは合金からなる薄膜を積層した積層構造である。前記薄膜のうち少なくとも１つは銀を主成分とし第２成分以下に標準電極電位が負である元素を少なくとも１種含有する下部銀系合金薄膜で形成し、該下部銀系合金薄膜の上に銀を主成分とし第２成分以下に標準電極電位が正である金属のみを含有する上部銀系合金薄膜を形成する。或いは前記下部銀系合金薄膜の上に金属若しくは合金からなる薄膜を中間層として少なくとも１層設けて該中間層の上に銀を主成分とし第２成分以下に標準電極電位が正である金属のみを含有する上部銀系合金薄膜を形成する。さらに前記上部銀系合金薄膜を前記下部銀系合金薄膜よりも薄く形成したことを特徴とする。
【００３６】
基板、下部銀系合金薄膜、上部銀系薄膜は前述したとおりである。中間層は、下部銀系合金薄膜と上部銀系薄膜の密着性、親和性を向上させるために設けても良い。また下部銀系合金薄膜、上部銀系薄膜とは別に機能を有する銀系合金薄膜としても良い。中間層の組成としては例えば、Ａｇ−Ｐｄ、Ａｇ−Ｃｕ、Ａｇ等が例示できる。
【００３７】
また、上部銀系合金薄膜に反射率及び耐食性の低下を生じさせない程度にＳｉＯ_２、Ａｌ_２Ｏ_３の少なくともいずれか一方を添加することも出来る。また、上部銀系合金薄膜は、１０ｎｍ以上の膜厚を有する。
【００３８】
なお、積層構造の最表層に特殊雰囲気からの保護を強化するための保護層を形成しても良い。
【００３９】
下部銀系合金薄膜は、耐候性は劣るものの耐熱性に優れた銀を５０原子％以上含有する銀−亜鉛−パラジウム−銅系合金とし、上部銀系合金薄膜は、耐熱性に劣るものの耐候性に優れた銀を５０原子％以上含有する銀−パラジウム系合金、または銀−パラジウム−銅系合金とすることが好ましい。反射率は共に高い。
【００４０】
図２の積層構造の変形として図３に示した積層構造としても良い。すなわち、基板と積層構造との密着性向上を目的として下地層を設けても良い。下地層としては、Ｓｉ、Ｔａ、Ｔｉ、Ｍｏ、Ｃｒ、Ａｌ、ＩＴＯ、ＩｒＯ_２、ＺｎＯ、ＳｉＯ_２、ＴｉＯ_２、Ｔａ_２Ｏ_５、ＺｒＯ_２等が例示できる。中間層は図３のように複層設けても良い。
【００４１】
以下に、材料的な改善方法として、Ａｇの結晶成長を抑制する効果の高い元素を添加する。Ａｇの結晶成長を抑制する元素としては、標準電極電位が正な元素よりも、負である元素の方が効果が高い。積層構造によるこの改善結果として実施例を示す。
【００４２】
【実施例】
ガラス基板上に反射膜を作製した。つまり、ガラス基板表面を常法により前処理を行なった後、第１の被覆層としてＡｇ−Ｐｄ−Ｃｕ−Ｚｎ（ＡＺＰＣ）が９６．２６−０．２６−０．５８−２．９ａｔ％である組成の下部銀系合金薄膜を、Ａｇ−Ｐｄ−Ｃｕ−Ｚｎ合金ターゲットを使用してスパッタリング法によって形成した。次に下部銀系合金薄膜の表面に第２の被覆層としてＡｇ−Ｐｄ−Ｃｕ（ＡＰＣ）が９８．０７−０．８７−１．０６ａｔ％である組成の上部銀系合金薄膜を、Ａｇ−Ｐｄ−Ｃｕ合金ターゲットを使用してスパッタリング法によって形成した。この時の被覆の膜厚は第１の被覆層を２００ｎｍ、第２の被覆層を１０ｎｍとして合計２１０ｎｍとしたものを作製した（実施例１−１）。また、第１の被覆層を２００ｎｍ、第２の被覆層を３０ｎｍとして合計２３０ｎｍとしたものを作製した（実施例１−２）。なお比較例として第１の被覆層ＡＺＰＣのみ単層の場合、並びに第２の被覆層ＡＰＣのみ単層の場合についても同様の試験を行って比較した。これら比較用のＡＺＰＣ単層、ＡＰＣ単層のそれぞれの膜厚は耐熱試験用には２００ｎｍ、また耐候性又は耐候性試験後に耐熱性試験を行ったものは１０ｎｍ及び３０ｎｍとした。
【００４３】
このときのスパッタリングの条件は以下のとおりである。成膜圧力０．３Ｐａ、成膜温度は常温でＲｆマグネトロンスパッタリングにて成膜を行った。
【００４４】
この様にして作成した反射膜について以下の評価試験を行った。試験条件は以下のとおりであった。（１）成膜直後、（２）湿度５０％のクリーンルーム大気中７２時間放置による耐候性試験、（３）２５０℃、１時間保持による耐熱性試験、（４） （２）を行った後（３）を行った耐候性試験後の耐熱性試験。（１）と（３）の評価方法として、原子間力顕微鏡（Ａｔｏｍｉｃ Ｆｏｒｃｅ Ｍｉｃｒｏｓｃｏｐｙ（ＡＦＭ））による表面状態の観察を行った。また、（１）、（２）、（４）の評価方法として、波長７００ｎｍ、５５０ｎｍ、及び４００ｎｍにおける反射率の測定を行った。
【００４５】
（１）のＡＦＭ像を図４に示した。（３）のＡＦＭ像を図５に示した。比較例としてＡＰＣ単層に（２）を行ったもののＡＦＭ像を図６に、ＡＺＰＣ単層に（２）を行ったもののＡＦＭ像を図７に示した。 この結果から、ＡＰＣ単層では耐熱性が十分でなく、本実施例のＡＺＰＣの上部にＡＰＣを薄く成膜したものは、ＡＺＰＣ単層と同様の耐熱性を維持していることがわかった。
【００４６】
次に（１）の反射率測定結果を表８に示した。（２）の反射率測定結果を表９に示した。（４）の反射率測定結果を表１０に示した。また、（２）と（１）の反射率の差Δ値である変化量を表１１に示した。
【表８】

【表９】

【表１０】

【表１１】

【００４７】
表８〜表１０より、ＡＺＰＣ単層に比べ、本実施例のＡＰＣを薄く積層したものはＡＰＣ単層と同等かそれ以上の耐候性を維持していることがわかった。また、耐候試験後の耐熱性はＡＰＣ単層、ＡＺＰＣ単層に比べ、本実施例のＡＺＰＣの上部にＡＰＣを薄く成膜したものが優れていることがわかった。
【００４８】
これら、図４〜図７と表８〜表１１により、耐熱性、耐候性共に、ＡＰＣ単層、ＡＺＰＣ単層に比べ、本実施例のＡＺＰＣの上部にＡＰＣを薄く成膜したものが優れていることがわかった。
【００４９】
これは、耐熱性の高い下部銀系合金薄膜の上部に耐候性の高い上部銀系合金薄膜を積層させることにより、下部銀系合金に含有されている標準電極電位が負の金属が化学反応、酸化、水酸化等の変質を引き起こす物質から保護する事で、反射率の低下を抑制したからである。
【００５０】
また、本積層構造の厚さの大半を耐熱性の高い下部銀系合金とする事で積層構造全体の結晶成長を最低限に抑制し、その上部に耐候性の高い上部銀系合金を薄く保護層として設ける事で、下部銀系合金が変質する様な物質から隔離する事で表面の変質による反射率低下を抑制したからである。
【００５１】
（比較例４）
さらに、下部銀系合金薄膜の膜厚を３０ｎｍ、上部銀系合金薄膜の膜厚を
２００ｎｍとした以外は実施例１−２と同様にして銀系合金薄膜の積層構造を作製して比較例３とした。比較例４は成膜後の初期特性については実施例と同等の性能を有しており問題なかったが、比較例４は耐熱性が実施例１−２と比較して劣っていた。
【００５２】
（比較例５）
ガラス基板上に反射膜を作製した。つまり、ガラス基板表面を常法により前処理を行なった後、第１の被覆層としてＡｇ−Ｐｄ−Ｃｕが９８．０７−０．８７−１．０６ａｔ％である組成の下部銀系合金薄膜を、Ａｇ−Ｐｄ−Ｃｕ合金ターゲットを使用してスパッタリング法によって形成した。次に下部銀系合金薄膜の表面に第２の被覆層としてＡｇ−Ｐｄ−Ｃｕ−Ｚｎが９６．２９−０．２６−０．５８−２．９ａｔ％である組成の上部銀系合金薄膜を、Ａｇ−Ｐｄ−Ｃｕ−Ｚｎ合金ターゲットを使用してスパッタリング法によって形成した。このときの被覆の厚さは下部銀系合金薄膜が２００ｎｍ、上部銀系合金薄膜が３０ｎｍであった。銀系合金の積層構造として厚みは２３０ｎｍであった。成膜は、成膜圧力０．５Ｐａ、成膜温度２５℃であり、マグネトロンスパッタリング装置を用いて行った。比較例５は成膜後の初期特性については実施例１と同等の性能を有しており問題なかったが、比較例５は耐候性、耐熱性共に実施例１と比較して劣っていた。
【００５３】
なお、表４に示した銀合金の組成の下部銀系合金薄膜、すなわち銀を主成分とし第２成分以下に標準電極電位が負である元素を少なくとも１種含有する下部銀系合金薄膜を２種類準備してこれらを積層させた場合は耐候性が不十分であった。
【００５４】
また、表５〜表７に示した上部銀系合金薄膜、すなわち銀を主成分とし第２成分以下に標準電極電位が正である金属のみを含有する上部銀系合金薄膜を２種類準備してこれらを積層させた場合は耐熱性が不十分であった。
【００５５】
ＡＺＰＣについて説明する。
下部銀系合金薄膜の組成として、次のものが例示できる。
優れた耐食性を有する銀合金であって、銀を主成分とし、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、ニッケル、パラジウム、白金、銅、金、亜鉛、アルミニウム、ガリウム、インジウム、ケイ素、ゲルマニウム及びスズからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
高反射率の特性を有する銀合金であって、銀を主成分とし、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、ニッケル、パラジウム、白金、銅、金、亜鉛、アルミニウム、ガリウム、インジウム、ケイ素、ゲルマニウム及びスズからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
電気的に低抵抗の特性を有する銀合金であって、銀を主成分とし、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、ニッケル、パラジウム、白金、銅、金、亜鉛、アルミニウム、ガリウム、インジウム、ケイ素、ゲルマニウム及びスズからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
優れた耐熱性を有する銀合金であって、銀を主成分とし、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、ニッケル、パラジウム、白金、銅、金、亜鉛、アルミニウム、ガリウム、インジウム、ケイ素、ゲルマニウム及びスズからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
上記の銀合金は、少なくとも１種類の各元素の含有量が０．１原子パーセント以上８．０原子パーセント以下であることを特徴とする銀合金である。
優れた耐食性を有する銀合金であって、銀を主成分とし、亜鉛、ニッケル、錫及びインジウムからなる群から選ばれた１種類の元素を含有し、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、パラジウム、白金、銅、金、アルミニウム、ガリウム、ケイ素、及びゲルマニウムからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
高反射率の特性を有する銀合金であって、銀を主成分とし、亜鉛、ニッケル、錫及びインジウムからなる群から選ばれた１種類の元素を含有し、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、パラジウム、白金、銅、金、アルミニウム、ガリウム、ケイ素、及びゲルマニウムからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
電気的に低抵抗の特性を有する銀合金であって、銀を主成分とし、亜鉛、ニッケル、錫及びインジウムからなる群から選ばれた１種類の元素を含有し、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、パラジウム、白金、銅、金、アルミニウム、ガリウム、ケイ素、及びゲルマニウムからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
優れた耐熱性を有する銀合金であって、銀を主成分とし、亜鉛、ニッケル、錫及びインジウムからなる群から選ばれた１種類の元素を含有し、チタン、ジルコニウム、ハフニウム、バナジウム、ニオブ、タンタル、クロム、モリブデン、タングステン、鉄、ルテニウム、コバルト、ロジウム、イリジウム、パラジウム、白金、銅、金、アルミニウム、ガリウム、ケイ素、及びゲルマニウムからなる群から選ばれた少なくとも１種類の元素を含有することを特徴とする銀合金である。
前記銀合金は、前記１種類の元素の含有量が０．１原子パーセント以上８．０原子パーセント以下であり、前記少なくとも１種類の各元素の含有量が０．１原子パーセント以上８．０原子パーセント以下であることを特徴とする銀合金である。
優れた耐熱性を有する銀合金であって、銀を主成分とし、亜鉛又はインジウムを０．１原子パーセント以上８．０原子パーセント以下含有し、銅を０．１原子パーセント以上８．０原子パーセント以下含有し、更にパラジウムを０．１原子パーセント以上８．０原子パーセント以下含有することを特徴とする銀合金である。
高反射率の特性を有する銀合金であって、銀を主成分とし、亜鉛又はインジウムを０．１原子パーセント以上８．０原子パーセント以下含有し、銅を０．１原子パーセント以上８．０原子パーセント以下含有し、更にパラジウムを０．１原子パーセント以上８．０原子パーセント以下含有することを特徴とする銀合金である。
電気的に低抵抗の特性を有する銀合金であって、銀を主成分とし、亜鉛又はインジウムを０．１原子パーセント以上８．０原子パーセント以下含有し、銅を０．１原子パーセント以上８．０原子パーセント以下含有し、更にパラジウムを０．１原子パーセント以上８．０原子パーセント以下含有することを特徴とする銀合金である。
優れた耐食性を有する銀合金であって、銀を主成分とし、亜鉛又はインジウムを０．１原子パーセント以上８．０原子パーセント以下含有し、銅を０．１原子パーセント以上８．０原子パーセント以下含有し、更にパラジウムを０．１原子パーセント以上８．０原子パーセント以下含有することを特徴とする銀合金である。
優れた耐熱性を有する銀合金であって、銀を主成分とし、亜鉛を３．０原子パーセント以上８．０原子パーセント以下含有し、銅を０．３原子パーセント以上１．７原子パーセント以下含有し、更にパラジウムを０．２原子パーセント以上３．０原子パーセント以下含有することを特徴とする銀合金である。
優れた耐食性を有する銀合金であって、銀を主成分とし、亜鉛を０．１原子パーセント以上８．０原子パーセント以下含有し、銅を０．１原子パーセント以上含有し、更にパラジウムを０．２原子パーセント以上含有することを特徴とする銀合金である。
優れた耐熱性及び耐食性を有する銀合金であって、銀を主成分とし、亜鉛を３．０原子パーセント以上８．０原子パーセント以下含有し、銅を０．３原子パーセント以上１．７原子パーセント以下含有し、更にパラジウムを０．２原子パーセント以上含有することを特徴とする銀合金である。
前記銀合金からなる下部銀系原型合金薄膜及び本願の銀系合金積層構造は、反射光の黄色化を抑制した反射型ＬＣＤ用反射板又は反射配線電極となる。
前記銀合金からなる下部銀系原型合金薄膜及び本願の銀系合金積層構造は、光学記録媒体ともなり得る。
エラストマー材料からなる基板と、この基板上に形成された電磁波遮蔽膜と、を備えた電磁波遮蔽体であって、前記電磁波遮蔽膜が本願に係る銀系合金の積層構造である電磁波遮蔽体である。
プラストマー材料からなる基板と、この基板上に形成された電磁波遮蔽膜と、を備えた電磁波遮蔽体であって、前記電磁波遮蔽膜が本願に係る銀系合金の積層構造である電磁波遮蔽体である。
前記電磁波遮蔽膜が１の膜又は複数の膜からなっていても良い。
記下地層は、インジウム・錫酸化物、酸化イリジウム、酸化亜鉛、二酸化ケイ素、酸化チタン、五酸化タンタル、酸化ジルコニウム、ケイ素、タンタル、チタン、モリブデン、クロム、アルミニウムからなる群から選ばれた１又は複数の材料、若しくは、該１又は複数の材料を少なくとも主成分として含む材料を用いて形成した薄膜であることを特徴とする。
前記銀合金からなることを特徴とする電子部品用金属材料である。
配線パターン、電極及び接点それぞれは、溶液によるエッチングにより形成されものである。
前記配線パターン、電極及び接点それぞれは、ガス雰囲気中でのエッチングにより形成されたものである。
前記配線パターン、電極及び接点それぞれが、タングステン、タンタル、モリブデン、酸化インジウム、酸化錫、窒化チタン、二酸化ケイ素、窒化シリコン、酸化チタン、酸化ニオブの何れか１種類もしくは複数で混合されて形成された下地層の上に形成されたものである。
前記配線パターン、電極及び接点それぞれが、ガラス又はプラストマー材料の基板上に直接形成されたものである。
前記銀合金からなる金属膜を、タングステン、タンタル、モリブデン、インジウム・錫酸化物、窒化チタン、二酸化ケイ素、窒化ケイ素の何れかによる下地の上に形成することにより、配線パターン、電極及び接点のうちの少なくとも１つを形成することを特徴とする銀系合金の積層構造の加工方法である。
前記銀合金からなる金属膜をガラス又はプラストマー材料の基板上に直接形成することにより、配線パターン、電極及び接点のうちの少なくとも１つを形成することを特徴とする銀系合金の積層構造の加工方法である。
前記の銀合金により形成された反射膜、配線パターン及び電極のうちの少なくとも１つを有することを特徴とする電子光学部品である。
上記に例示した下部銀系合金及び本願の銀系合金の積層構造は下記の問題を解決する。
従来の金属材料では、優れた耐食性、高反射率、電気的に低抵抗、優れた耐熱性を有する材料に対する開発が必ずしも十分ではなかった。
また、従来の反射型液晶表示パネルでは、反射型ＬＣＤ用反射板の製造時又は使用時において、大気中の硫黄、酸素、水分等と反応することがあり、それにより、反射特性が劣化し、反射光の色度が変化し、黄色に変色してしまうという黄色化の問題があった。
また、ＡｌあるいはＡｌ合金により形成した薄膜では、光学記録媒体の用途によってはいまだ充分な反射率が得られているとはいえない。また、耐候性や、薄膜を形成した場合の反射率、透過率について十分な特性を有する合金材料の開発は未だなされていない。
また、前記従来のエラストマー材料を用いた電磁波遮蔽体では、複雑な形状への折り曲げ追随性、耐腐食性、耐候性や耐摩耗性等にも問題があり、ＥＭＣ素材として全く採用（適用）されない等の問題があった。
また、前記従来のプラストマー材料基板を用いた電磁波遮蔽体では、電磁波遮蔽性、赤外線遮蔽性、透明性、非視認性、耐腐食性、耐候性や耐摩耗性等が十分に満たされてなく、ＥＭＣ素材として全く採用（適用）されない等の問題があった。
また、従来の電子機器、電子部品では、電気的な低抵抗率が十分でなく、加工性に優れた配線材料、電極材料、接点材料が開発されていなかった。
また、建材ガラス用赤外線及び熱線を反射する反射膜としては、ＡｇやＡｌ若しくはこれらのうちいずれかの元素を主成分とする合金材料から形成された反射膜が幅広く知られている。しかし、これらの反射膜は耐熱性に対して決して優れているとは言えない。
例えばＡｇやＡｌは熱に対しての耐熱性が高くなく、特定温度では表面部が拡散し易いために、例えば液晶表示素子用の反射板を製作する場合には、製作プロセス中での温度雰囲気が制限される。更に、建材ガラス用の赤外線及び熱線反射膜に至っては、大気中で夏季に高温に曝されると、反射膜自体が化学的に変異（変色）してしまう等、熱に対しての品質の安定性に問題があった。
また、反射率が高い材料としては、ＡｇやＡｌ以外にＡｕが知られているが、Ａｕは価格的に大変高価であるため、建材窓ガラス用反射膜に用いるにはコスト的な面から実用性が乏しいと判断されている。
また、反射率が高く、コスト的な面からも大変安価で、実用性が高いとされるＡｌについては、ＰＭＭＡ、シリコーン樹脂等の樹脂基板等を用いた場合に、樹脂基板から析出されるガス成分に対して化学反応を起こす虞れがある。このことから、ガスの放出作用が低い材料からなる基板にのみ有効となって、基板材料が制限されてしまうばかりか、樹脂とのコンタクトを図る場合には材料の化学的な安定性が懸念されてしまう等の不安、課題が残る。
また、４００〜４０００ｎｍの可視及び赤外域と称される光学波長領域中で、Ａｇは数多くの金属元素中で最も光学反射率が高いために、高反射率を特徴とする膜としては優れた特性を保持しているものと検討されている。しかし、熱に対しての自己拡散エネルギーが活発であるために、熱が加えられた場合に経時変化が生じるという問題がある。そのため、一時的であっても１００℃前後の熱が加えられた場合には表面部に拡散現象が起こり、Ａｇ本来が保有する光沢を失って白濁化してしまう。換言すれば、反射率が高いというＡｇ本来の特性が大幅に低減してしまう。
また、ガラスや樹脂製の基板上に反射膜を形成した際には、Ａｇは大気中に放置されると、大気中の湿気（主として水分）を吸収して黄色化してしまうため、反射率が高いというＡｇ本来の特性が損なわれてしまう等の問題が生じる。従って、高反射率であるという本来の特性を保持することができず、耐候性に対しても決して優れているとは言えない。
本発明は前記諸問題を考慮してなされたものであり、その目的は、優れた耐食性を有する銀合金を提供することにある。また、本発明の他の目的は、高い反射率を有する銀合金を提供することにある。また、本発明の他の目的は、電気的に低抵抗の特性を有する銀合金を提供することにある。また、本発明の他の目的は、優れた耐熱性を有する銀合金を提供することにある。
また、本発明の他の目的は、反射光の黄色化を抑制したスパッタリングターゲット、反射型ＬＣＤ用反射板、反射配線電極、薄膜及びその製造方法を提供することにある。
また、本発明の他の目的は、Ａｇと比較した場合に高反射率を維持し、耐候性を改善した光学記録媒体を提供することにある。
また、本発明の他の目的は、半透明反射膜の耐候性が改善され、より高い信頼性が得られる光学記録媒体を提供することにある。
また、本発明の他の目的は、柔軟性、形状自在性（複雑な形状への折り曲げ追随性）を備え、主にＥＭＣ対策材料として応用展開が広く、また、高温高湿の環境下においても高い電磁波遮蔽能力が継続的に保持されるといった耐候性の材料的な安定性が格段に改善され、しかも、エラストマー材料基板との接合性（密着性）がより一層効果的に強化され、より高い信頼性が得られる電磁波遮蔽体を提供することにある。
また、本発明の他の目的は、電磁波遮蔽性と赤外線遮蔽性、透明性、非視認性、耐腐食性、耐候性や耐摩耗性等を備え、主にＥＭＣ対策材料として応用展開が広く、また、高温高湿の環境下においても高い電磁波遮蔽能力が継続的に保持されるといった耐候性の材料的な安定性が格段に改善され、しかも、プラストマー材料基板との接合性（密着性）がより一層効果的に強化され、より高い信頼性が得られる電磁波遮蔽体を提供することにある。
また、本発明の他の目的は、従来に比して電気的に低抵抗率であって、安定かつ加工性に優れた電子部品用金属材料、配線材料、銀合金を使用した電子部品、電子機器、金属膜の加工方法、電子光学部品を提供することにある。
また、本発明の他の目的は、Ａｇ自体の保有する高い光学特性が保持され、更にはＡｇの材料的な安定性が格段に改善されるとともに、信頼性の高い高耐熱性反射膜を用いた積層体及び建材ガラスを提供することにある。
Ａｇ−Ｚｎ−Ｐｄ−Ｃｕ系銀合金は、優れた耐食性、高反射率、電気的に低抵抗及び優れた耐熱性のうちの少なくとも１つの特性を有する銀合金であって、Ａｇ主成分とし、Ｚｎを０．１ａｔ％以上８．０ａｔ％以下含有し、Ｃｕを０．１ａｔ％以上８．０ａｔ％以下含有し、更にＰｄを０．１ａｔ％以上８．０ａｔ％以下含有する合金である。また、より好ましくは、Ｚｎの含有量が０．１ａｔ％以上５．０ａｔ％以下、Ｃｕの含有量が０．１ａｔ％以上５．０ａｔ％以下、Ｐｄの含有量が０．１ａｔ％以上５．０ａｔ％以下である。
Ａｇ−Ｉｎ−Ｐｄ−Ｃｕ系銀合金は、優れた耐食性、高反射率、電気的に低抵抗及び優れた耐熱性のうちの少なくとも１つの特性を有する銀合金であって、Ａｇ主成分とし、Ｉｎを０．１ａｔ％以上８．０ａｔ％以下含有し、Ｃｕを０．１ａｔ％以上８．０ａｔ％以下含有し、更にＰｄを０．１ａｔ％以上８．０ａｔ％以下含有する合金である。また、より好ましくは、Ｉｎの含有量が０．１ａｔ％以上５．０ａｔ％以下、Ｃｕの含有量が０．１ａｔ％以上５．０ａｔ％以下、Ｐｄの含有量が０．１ａｔ％以上５．０ａｔ％以下である。
またＡｇ−Ｚｎ−Ｐｄ−Ｃｕ系銀合金は、優れた耐熱性を有する銀合金であって、Ａｇを主成分とし、Ｚｎを３．０ａｔ％以上８．０ａｔ％以下含有し、Ｃｕを０．３ａｔ％以上１．７ａｔ％以下含有し、更にＰｄを０．２ａｔ％以上３．０ａｔ％以下含有する合金である。また、特に好ましい耐熱性を有する銀合金中のＣｕの含有量は０．３ａｔ％以上０．５ａｔ％以下である。
またＡｇ−Ｚｎ−Ｐｄ−Ｃｕ系銀合金は、優れた耐食性を有する銀合金であって、Ａｇを主成分とし、Ｚｎを０．１ａｔ％以上８．０ａｔ％以下含有し、Ｃｕを０．１ａｔ％以上含有し、更にＰｄを０．２ａｔ％以上含有する合金である。
またＡｇ−Ｚｎ−Ｐｄ−Ｃｕ系銀合金は、優れた耐熱性及び耐食性を有する銀合金であって、Ａｇを主成分とし、Ｚｎを３．０ａｔ％以上８．０ａｔ％以下含有し、Ｃｕを０．３ａｔ％以上１．７ａｔ％以下含有し、更にＰｄを０．２ａｔ％以上含有する合金である。また、特に好ましい耐熱性を有する銀合金中のＣｕの含有量は０．３ａｔ％以上０．５ａｔ％以下である。
上記の組成の銀合金ターゲットを作製して薄膜を形成しても良い。スパッタリングターゲットの場合、前述した銀合金からなるインゴットを鋳造法により製造する。また、スパッタリングターゲットの他の製造方法について説明する。スパッタリングターゲット材の製造方法としては、大気雰囲気中の溶解法、あるいは真空中での溶融法が挙げられる。前述した銀合金を溶融法で製造する場合には、先ず、基となる母合金を作製し、これにＡｇを追加で混入して、Ａｇが規定量になるように合金に含有される金属の含有量を整えるものとする。
大気中で行なう場合について説明する。先ず、アルゴン（以下、Ａｒ）雰囲気（４００〜６００Ｔｏｒｒ）中で、前述した銀合金をアーク溶解にて溶融混合することにより、母合金を作製する。
次に、高周波溶融炉において、Ａｇの溶解を行なう。このときのＡｇの量は、全体溶解量から母合金中のＡｇの量を差し引いた量とする。この際の溶融温度は、例えば１０００〜１５００℃として、例えば、０．１〜０．２リットルの並型黒鉛坩堝を用いる。
完全に溶融した後、酸化防止材を投入し、溶融中の酸素との固溶を抑制、防止する。酸化防止材としては、ホウ砂、ホウ酸ナトリウム、ホウ酸リチウム、カーボン等を用いることができる。
完全に溶融した状態で、約１時間放置し、前記の母合金を添加してさらに０．５〜１時間溶融させる。この際の溶融温度は、例えば１０５０〜２０００℃とする。
次に、例えばアルミナ、あるいはタルクを内面に塗布してあるＦｅの鋳型に溶融物を注湯する。Ｆｅの鋳型は、引け巣を防止するため、予め電気炉等で３００〜５００℃程度に熱しておく。
鋳型内の溶融物を冷却、凝固し、インゴットを鋳型から取り出して、常温まで冷却する。次に、インゴットの最上部の押湯部を切断除去し、インゴットを圧延機により圧延し、９０ｍｍ×９０ｍｍ×８．１ｍｍの板状の合金を作製する。
その後、例えば４００〜５００℃の温度で電気炉内にＡｒガスを封入した状態で、１〜１．５時間程度、熱処理し、その後さらにプレス機によりそり修正を行なう。
その後、製品形状にワイヤーカットし、耐水研磨紙を用いて製品全面を研磨し、表面粗度を調整し、最終的にＡｇ合金のスパッタリングターゲット材を作製することができる。
以上、大気中での溶解法について説明したが、その他の溶解法を用いることも可能であり、以下、Ａｒ雰囲気中で行なう溶解の場合について説明する。
先ず、Ａｒ雰囲気（４００〜６００Ｔｏｒｒ）中で、前述した銀合金をアーク溶解にて溶融混合し、母合金を作製する。
次に、高周波溶融炉において、前記の母合金とＡｇの溶解を行なう。このときのＡｇの量は、全体溶解量から母合金中のＡｇの量を差し引いた量とする。
母合金とＡｇを入れた坩堝を高周波溶融炉に入れ、真空引きを行なう。酸素を巻き込まない程度に真空に引いた後、溶融炉をＡｒ雰囲気（１００〜６００Ｔｏｒｒ）にしてから溶融を開始する。
この際の溶融温度は、例えば、１０５０〜１４００℃とし、坩堝は、例えば、０．１〜０．２リットルの並型黒鉛坩堝を用いる。
次に、例えばアルミナ、あるいはタルクを内面に塗布してあるＦｅの鋳型に溶融物を注湯する。
Ｆｅの鋳型は、引け巣を防止するため、予め電気炉等で３００〜５００℃程度に熱しておく。
鋳型内の溶融物を、冷却、凝固し、インゴットを鋳型から取り出して、常温まで冷却する。
次に、インゴットの最上部の押湯部を切断除去し、インゴットを圧延機により圧延し、９０ｍｍ×９０ｍｍ×８．１ｍｍの板状の合金を作製する。
その後、例えば電気炉で４００〜５００℃によりＡｒガスを封入した状態で、１〜１．５時間程度、熱処理し、その後さらにプレス機によりそり修正を行なう。
その後、製品形状にワイヤーカットし、耐水研磨紙を用いて製品全面を研磨し、表面粗度を調整し、最終的に本発明の銀合金のスパッタリングターゲット材を作製することができる。
前述のように、本発明の銀合金のスパッタリングターゲット材を作製する場合において、Ａｇに対してＺｎ及びその他の元素Ｘを添加して溶融する場合においても、従来行われている容易な方法を適用することができ、価格的にも製法的にもメリットが大きい。
Ｚｎ、Ｎｉ、Ｓｎ及びＩｎを含有させるのは、塩化、硫化防止及び脱酸素効果（酸化防止）、マイグレーション防止（イオン化防止）のためであり、Ｐｄを含有させたのはＡｇに対して共晶合金を作る為に耐食性がさらに上がると考察される為である。また、前記少なくとも１種類の各元素で、例えばＣｕを含有させるのは、電気抵抗を下げること、Ａｇ合金の加工性を上げること、マイグレーション防止等を目的としている。
また、前記銀合金では、後述する反射率の測定において表１３、表１４に示すように実用上高い反射率が得られることが確認されている。また、後述する抵抗値の測定において表１２に示すように電気的に低抵抗化が実現できることが確認されている。
【表１２】

本願の下部銀系合金薄膜及び上部銀系合金薄膜は、前記スパッタリングターゲットを用いたスパッタ装置において例えばＲＦ（交流）マグネトロンスパッタリング法により形成される。従って、この薄膜のいずれかからなる反射型ＬＣＤ用反射板は、微視的にみても均一な特性を安定に提供することができる。
前述した銀合金からなる薄膜によって反射型ＬＣＤ用反射板を形成している。このため、この反射型ＬＣＤ用反射板の製造時又は使用時において、大気中の硫黄、酸素、水分等と反応することを抑制できる。従って、反射光の色度が変化し、黄色に変色してしまうという黄色化を抑制することができる。また、反射光を高反射率化（即ち反射光の反射率を向上）することができ、安定的に高い反射率を確保することができる。
次に、本発明に係る第４の実施の形態による反射配線電極及びその製造方法について説明する。反射配線電極は前記薄膜のいずれかからなるものである。
前記薄膜は、前記スパッタリングターゲットを用いたスパッタ装置においてＲＦ（交流）マグネトロンスパッタリング法により成膜され、その後、エッチングにより所定形状に加工される。この薄膜からなる反射配線電極は、微視的にみても均一な特性を安定に提供することができる。また、前記薄膜は、例えば、燐酸を含有するエッチング液でエッチング加工することが可能である。燐酸系のエッチング液としては、例えばＨ_３ＰＯ_４＋ＨＮＯ_３＋ＣＨ_３ＣＯＯＨを用いることが可能である。
また、前記反射型ＬＣＤ用反射板及び反射配線電極それぞれは石英ガラス基板などの下地に対して十分な密着性を有するものである。
尚、前記実施の形態では、薄膜をスパッタリング法により成膜しているが、薄膜を蒸着法、ＣＶＤ法、メッキ法などの他の成膜法により成膜することも可能である。
Ａｇに所定量のＰｄ、Ｃｕ、Ｚｎを添加したＡｇ−Ｐｄ−Ｃｕ−Ｚｎ合金、又は、Ａｇに所定量のＰｄ、Ｃｕ、Ｉｎを添加したＡｇ−Ｐｄ−Ｃｕ−Ｉｎ合金により、光学記録媒体用の薄膜、すなわち、反射膜を形成して光学記録媒体を作製した場合の４００ｎｍの波長レーザー光に対する反射率、５５０ｎｍの波長レーザー光に対する反射率を測定した。この場合の測定結果を表１４に示す。比較例としてＡｇを主成分とし、Ｐｄを０．５ａｔ％とＣｕを１．０ａｔ％含有したＡｇ−０．５ａｔ％Ｐｄ‐１．０ａｔ％合金の薄膜についての反射率を測定した。
【表１３】

表１３に示した測定結果より、ＡｇにＰｄ、Ｃｕ、Ｚｎ又はＩｎを含有しているＡｇ合金のスパッタリングターゲット材を用いて、光学記録媒体の薄膜を形成した場合においては、実用上望ましい高い反射率が得られることがわかる。
次に、表１３に示した薄膜を２５０℃の温度で１時間熱処理を施した後の４００ｎｍの波長レーザー光に対する反射率、５５０ｎｍの波長レーザー光に対する反射率を測定した。この場合の測定結果を表１４に示す。
【表１４】

表１４に示した測定結果より、実用上望ましい高い反射率が得られることがわかる。
また、Ａｇは、硫黄と結合しやすいので大気中に長時間放置されると、Ａｇ_２Ｓとなり黒色化する。この結果、Ａｇ薄膜の光学特性が劣化する。また、Ａｇは、塩素とも激しく反応してＡｇＣｌとなり白濁化する。この結果、Ａｇ薄膜の光学特性が劣化する。しかし、Ａｇは、酸素、水素、あるいは水に対しては比較的安定な物質である。一方、Ｚｎ、Ｉｎ、Ｓｎ及びＮｉは、脱酸素効果（酸化防止）、硫化、塩化防止等の作用があり、硫黄や塩素に対して化学的に安定な物質である。
前記Ａｇ合金のスパッタリングターゲットによれば、塩素、水素、酸素、硫黄という、大気中、あるいは特殊環境中で検討される非金属元素による汚染や光学記録媒体に採用される際に要求される環境や雰囲気下での高い耐候性の向上の実現が可能になる。
耐食性試験（５％ＮａＣｌ浸水試験）及びその結果について説明する。 ５％ＮａＣｌ浸水試験のサンプルは、ポリカーボネート基板上に表中に示す組成（ａｔ％表示）のＡｇ合金を成膜したものを使用した。 ５％ＮａＣｌ浸水試験は、常温で、５％濃度の塩水にこのサンプルを浸漬した後、３分経過後、３時間経過後、２４時間経過後に目視により確認したものである。
表１６に示すように、Ａｇ−Ｚｎ−Ｃｕ−Ｐｄ合金中のＰｄの含有量が０．１ａｔ％の場合、２４時間経過後に若干の白色が観察されたが、Ｐｄの含有量が０．２ａｔ％以上の場合は２４時間経過後も変化が無かった。したがって、耐食性を得るためにはＰｄの含有量を０．２ａｔ％以上とすれば良いことが確認された。
表１７に示すように、Ａｇ−Ｚｎ−Ｃｕ−Ｐｄ合金中のＣｕの含有量を０ａｔ％〜５．０ａｔ％まで変えたサンプルで耐食性試験を行った場合、いずれのサンプルも２４時間経過後の変化が観察されなかった。したがって、この合金ではＣｕの組成が耐食性に影響しないことが確認された。
表１５に示すように、Ａｇ−Ｚｎ−Ｃｕ−Ｐｄ合金中のＺｎの含有量を０．８ａｔ％〜８．０ａｔ％まで変えたサンプルで耐食性試験を行った場合、いずれのサンプルも２４時間経過後の変化が観察されなかった。したがって、この合金ではＣｕの組成が耐食性に影響しないことが確認された。
【表１５】

【表１６】

【表１７】

基板がエラストマー材料の時、その材料としては、シリコーンゴム、天然ゴム、クロロプレンゴム又はＥＰＤＭ（エチレン・プロピレンとジエンとのゴム状三元共重合体）等が挙げられる。
また、基板がプラストマー材料の時、その材料としては、例としてプラスチックフィルムやエンジニアリングプラスチック等が挙げられ、主な種類として、ポリアミド、ポリカーボネート、ポリアセタール、或いはポリブチレンテレフタレート、変性ポリフェニレンエーテル等が挙げられる。
密着助長下地膜の材料としては、酸素や各種の材質からなる基板に対して材料的に安定であり、前記基板と少なくとも前記銀合金からなる電磁波遮蔽膜との密着性を考慮すると、Ｓｉ、Ｔａ、Ｔｉ、Ｍｏ、Ｃｒ、Ａｌ、ＩＴＯ、ＩｒＯ_２、ＺｎＯ、ＳｉＯ_２、ＴｉＯ_２、Ｔａ_２Ｏ_５、ＺｒＯ_２等からなる群から選ばれた１又は複数の材料、若しくは、該１又は複数の材料を少なくとも主成分として含む材料を用いて形成したものであることが好ましい。
また、前述した銀合金は、シリコーンゴム、天然ゴム、クロロプレンゴム又はＥＰＤＭ等の各種のエラストマー材料に対して化学的安定性が高く、エラストマー材料からなる基板材質に対して制限されないことも確認されている。
また、前述した銀合金は、ポリアミド、ポリカーボネート、ポリアセタール、或いはポリブチレンテレフタレート、変性ポリフェニレンエーテル等の各種のプラストマー材料に対して化学的安定性が高く、プラストマー材料からなる基板材質に対して制限されないことも確認されている。
また、各種のエラストマー材料からなる基板の密着助長下地膜としては、Ｓｉ、Ｔａ、Ｔｉ、Ｍｏ、Ｃｒ、Ａｌ、ＩＴＯ、ＺｎＯ、ＳｉＯ_２、ＴｉＯ_２、Ｔａ_２Ｏ_５、ＺｒＯ_２が望ましい。
その理由としては、シリコーンゴム、天然ゴム、クロロプレンゴム又はＥＰＤＭからなる基板は特定の純度や材質の場合にはガスの発生が大変多いこと、金属はその発生ガスと反応が強いこと、銀合金の薄膜と密着させる接合、界面に反応不動態被膜（例えば酸化膜等）を生じる可能性が高いこと等から適切であるとは言い難いからである。
５５０ｎｍの波長の光に対する反射率を前記試験試料片の薄膜（成膜直後のもの）で測定した。次に、この試験試料片を大気中でオーブンに入れ約１時間放置して５５０ｎｍの波長の光に対する反射率を測定した。この時のオーブンの加熱方法としては、抵抗加熱式を採用し、加熱温度を２５０℃、加熱速度を２０℃／ｍｉｎに設定した。そして、成膜直後の薄膜の反射率に対して１時間加熱した後の反射率の変化率を計算した。これらの試験結果を表１８及び表１９に示す。前記銀合金では、後述する耐熱性試験において表１８、表１９に示すようにアニール後の反射率の減少が少ないという耐熱性に優れているといった結果が得られており、更に耐食性試験において表１２に示すようにＮａＣｌに対して良好な結果が得られているので、耐熱性及び耐食性に優れた銀合金であることが確認されている。
【表１８】

【表１９】

【００５６】
【発明の効果】
本発明により、低電気抵抗、耐食性、耐熱性、加工性、密着性及び高反射率を全て所定レベル以上に兼ね備えた銀系合金の積層構造を提供することができた。すなわち本発明は、耐熱性に特化した材料と、耐候性に特化した材料の２つを組み合わせることで、下部の層には耐熱性の高いＡｇ合金を設け、高い耐熱性を得ることを目的とする。さらにその上部に耐候性の高いＡｇ合金を設け、下部のＡｇ合金が変質する事を防ぐことができた。また、本発明により、反射板、電極、配線、反射電極、反射配線など様々な用途への使用を可能とした。
【図面の簡単な説明】
【図１】本実施例の銀合金の積層構造の一形態を示す図である。
【図２】本実施例の銀合金の積層構造の第２の形態を示す図である。
【図３】本実施例の銀合金の積層構造の第３の形態を示す図である。
【図４】実施例の（１）初期の表面ＡＦＭ写真の画像である。
【図５】実施例の（３）耐候性評価後のＡＦＭ写真の画像である。
【図６】比較例のＡＰＣ単層に（２）を行ったもののＡＦＭの画像である。
【図７】比較例のＡＺＰＣ単層に（２）を行ったもののＡＦＭの画像である。
【図８】Ａｇ−０．５ａｔ％Ｐｄ−１．０ａｔ％ＣｕにＺｎを１．８〜７．３ａｔ％まで添加し、２５０℃で１時間のアニール試験を行った後の試料表面を顕微鏡観察した結果を示す写真の画像である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a reflective film, a reflective electrode film or an electrode film of a display such as a liquid crystal display, low electric resistance suitable for wiring, weather resistance (including moisture resistance), heat resistance, workability (good etching property), and adhesion. In addition, the present invention relates to a laminated structure of a silver-based alloy having both high reflectivity and an electrode, a wiring, a reflective film, and a reflective electrode using the same.
[0002]
[Prior art]
Ag-Pd-Cu-based silver alloys are disclosed as silver-based alloys suitable for a reflective film, a reflective electrode film or an electrode film, and wiring of a display such as a liquid crystal display (for example, see Patent Documents 1 to 3).
[Patent Document 1] JP-A-2002-277855, Claim 4
[Patent Document 2] JP-A-2002-226765, Claim 2
[Patent Document 3] Japanese Patent Application Laid-Open No. 2001-221908, Claim 3
[Patent Document 4] Japanese Patent Application Laid-Open No. 2001-210989, Claim 1
[0003]
However, for use in applications such as a reflective film and a reflective electrode film of a display such as a liquid crystal display, the electric resistance, weather resistance, heat resistance, workability, adhesion, and high reflectance are all combined at a predetermined level or more. Needed. In this regard, the silver-based alloys described in Patent Literatures 1 to 4 have a problem in heat resistance, and an increase in surface roughness due to a heating step of a color filter or the like and a decrease in reflectance due to generation of hillocks have occurred.
[0004]
Silver based material that excels in all required properties such as hillock resistance, moisture resistance, weather resistance, reflectance in film forming state (As-Depo), maintenance of reflectance after long time standing after film formation, and low electric resistance No alloy was present. The reason is that, for example, there is a trade-off relationship between moisture resistance and heat resistance, and it is difficult to achieve both characteristics at a high level.
[0005]
When a transparent oxide film is laminated on top of silver or almost all silver alloys as a protective film, hillock suppression, or as an optical correction film, the reflectance in the entire visible light wavelength region or a part of the wavelength region is reduced. Was done.
[Problems to be solved by the invention]
[0006]
The present invention provides low electric resistance, weather resistance, heat resistance, workability, adhesion and high reflectivity in view of the fact that there is no silver-based alloy having all of these properties at a predetermined level or more. To provide a laminated structure of a silver-based alloy. That is, an object of the present invention is to make use of the advantages of both materials and to compensate for the disadvantages by combining two materials, a material specialized in heat resistance and a material specialized in weather resistance. The lower layer is provided with an Ag alloy having high heat resistance, with the object of obtaining high heat resistance. A further object of the present invention is to provide an Ag alloy having high weather resistance on an upper portion thereof to prevent the lower Ag alloy from being deteriorated.
[0007]
An object of the present invention is to provide an Ag alloy laminate that makes use of the advantages of both the lower layer and the upper layer and compensates for the disadvantages. Therefore, the material combined with the lower and upper layers is a material specialized in heat resistance. And combinations other than those specializing in weather resistance. For example, an object is to provide a laminated body having both good etching properties and high reflectivity by combining a material specialized in etching properties in a lower part and a material specialized in reflectance in an upper part. Another object of the present invention is to provide a laminated body having both low resistance and high weather resistance by combining a material specializing in low resistance at the lower part and a material specializing in weather resistance at the upper part. These applications are intended for use in various applications such as reflectors, electrodes, wiring, reflective electrodes, and reflective wiring.
[0008]
[Means for Solving the Problems]
The laminated structure of the silver-based alloy according to the present invention forms, on a substrate, a lower silver-based alloy thin film containing silver as a main component and at least one element having a negative standard electrode potential below the second component. An upper silver-based alloy thin film containing silver as a main component and only a metal having a positive standard electrode potential below a second component is formed thinner than the lower silver-based alloy thin film on the lower silver-based alloy thin film. And
[0009]
The laminated structure of the silver-based alloy according to the present invention is a laminated structure in which a thin film made of a metal or an alloy is laminated on a substrate, and at least one of the thin films contains silver as a main component and a second or lower component as a standard electrode. A lower silver-based alloy thin film containing at least one element having a negative potential is formed on the lower silver-based alloy thin film. An upper silver-based alloy thin film is formed, or at least one thin film made of a metal or an alloy is provided as an intermediate layer on the lower silver-based alloy thin film. Hereinafter, an upper silver-based alloy thin film containing only a metal having a positive standard electrode potential is formed, and the upper silver-based alloy thin film is formed thinner than the lower silver-based alloy thin film.
[0010]
In the silver-based alloy laminated structure according to the present invention, the upper silver-based alloy thin film is formed of SiO. ₂ , Al ₂ O ₃ It is preferable to add at least one of these.
[0011]
In the silver-based alloy laminated structure according to the present invention, the upper silver-based alloy thin film preferably has a thickness of 10 nm or more.
[0012]
In the silver-based alloy laminated structure according to the present invention, it is preferable that the intermediate layer is an adhesion layer for enhancing the affinity between the lower silver-based alloy thin film and the upper silver-based alloy thin film.
[0013]
In the laminated structure of the silver-based alloy according to the present invention, it is preferable that an underlayer for strengthening the adhesion between the substrate and the laminated structure is formed on the substrate.
[0014]
In the laminated structure of the silver-based alloy according to the present invention, it is preferable that a protective layer for enhancing protection from a special atmosphere is formed on the outermost layer of the laminated structure.
[0015]
In the silver-based alloy laminated structure according to the present invention, the substrate is preferably a glass substrate, a resin substrate, or a glass / resin laminated substrate.
[0016]
In the laminated structure of a silver-based alloy according to the present invention, the lower silver-based alloy thin film is preferably a silver-zinc-palladium-copper-based alloy containing 50 atomic% or more of silver.
[0017]
In the laminated structure of a silver-based alloy according to the present invention, the upper silver-based alloy thin film is preferably a silver-palladium-based alloy containing 50 atomic% or more of silver or a silver-palladium-copper-based alloy.
[0018]
The silver-based alloy electrode according to the present invention is characterized by having a laminated structure of the silver-based alloy.
[0019]
The silver-based alloy wiring according to the present invention is characterized in that a laminated structure of the silver-based alloy is formed by patterning.
[0020]
The silver-based alloy reflective film according to the present invention is characterized by having a laminated structure of the silver-based alloy.
[0021]
The silver-based alloy reflective electrode according to the present invention has a stacked structure of the silver-based alloy.
[0022]
A self-luminous display according to the present invention is characterized in that the display has a laminated structure of the silver-based alloy.
[0023]
The flat panel display according to the present invention is characterized by having a laminated structure of the silver-based alloy.
[0024]
The semiconductor device according to the present invention is characterized by having a laminated structure of the silver alloy.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not construed as being limited to these descriptions.
[0026]
FIG. 1 shows one embodiment of the laminated structure of the silver alloy of this embodiment. As shown in FIG. 1, the laminated structure of the silver-based alloy is such that a lower silver-based alloy thin film containing silver as a main component and at least one element having a negative standard electrode potential below the second component is formed on a substrate. Forming an upper silver-based alloy thin film containing silver as a main component and only a metal having a positive standard electrode potential below the second component on the lower silver-based alloy thin film thinner than the lower silver-based alloy thin film; . In the present invention, a silver alloy containing silver as a main component means a silver alloy containing 50 atomic% or more of silver.
[0027]
Glass substrate made of non-alkali glass, soda-lime glass, etc., Al ₂ O ₃ And sapphire substrates, and various plastomer materials such as polyamide, polycarbonate, polyacetal, or polybutylene terephthalate, modified polyphenylene ether, various elastomer materials, and resin substrates such as silicone rubber, natural rubber, chloroprene rubber, and EPDM. Further, a substrate in which a resin is coated on a glass substrate may be used.
[0028]
The lower silver-based alloy thin film is a silver-based alloy containing silver as a main component and at least one element having a negative standard electrode potential below the second component. Table 1 shows a list of elements having a negative standard electrode potential. For example, Li, Be, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, C, Ni, Zn, Ga, Ge, Rb, Sr, Y, Zr, Nb, Mo , In, Sn, Cs, Ba, Hf, Ta, W, Tl, Bi, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ac , Th, Pa, and C can be exemplified. Further, in addition to the metals shown in Table 1, the lower silver-based alloy thin film may contain the platinum group, gold, and copper shown in Table 2 below the second component. Further, the lower silver-based alloy thin film may contain an oxide shown in Table 3.
[Table 1]

[Table 2]

[Table 3]

[0029]
The composition of the lower silver-based alloy thin film includes AgZnPdCu, AgNdCu, AgNd, AgZnCu, AgSnCu, AgInCu, Ag-Mg, Ag-Li, AgZn, AgZnCu, AgZnPdCu, AgNd, AgNdCu, AgNTi, AgNTi, AgNdAg , AgNdAu, AgNdCuAu, AgNdCuPd, AgSn, AgSnCu, AgIn, AgInCu, AgTi, AgTiCu, AgAl, AgAlCu, AgGe, AgGeCu, AgMg, AgMgCu, AgMgPg, AgMgAg, CuAg, AgMgAg , AgC, AgNb, AgNbCu, AgPdAl, AgPdCuAl, AgZnPdAl u, can be exemplified AgLi, AgLiCu, AgLiPd, AgLiPdCu, AgLiMg, AgLiMgCu, the AgITO, AgSnO2, AgInO2, AgZnO. Table 4 shows the composition of the lower silver alloy thin film.
[Table 4]

[0030]
The upper silver-based alloy thin film is a silver-based alloy containing silver as a main component and only a metal having a positive standard electrode potential below the second component. Metals having a positive standard electrode potential are Cu, Ru, Rh, Pd, Re, Os, Ir, Pt, and Au. Examples of the composition of the upper silver-based alloy thin film include those shown in Tables 5 to 7 including AgPdCu. In Tables 5 to 7, “○” means that the metal is contained.
[Table 5]

[Table 6]

[Table 7]

[0031]
The upper silver-based alloy thin film is formed thinner than the lower silver-based alloy thin film. The reason for this is that the upper silver-based alloy thin film functions as a kind of protective film, and heat resistance is mainly ensured by the lower silver-based thin film. The thickness of the upper silver alloy thin film is preferably 10 nm (100 °) or more. If the thickness is less than 10 nm, the function as a protective film is reduced, and it becomes impossible to secure the moisture resistance of the lower silver-based thin film.
[0032]
The decrease in the reflectance of the reflective film is mainly caused by the following two reasons.
{Circle around (1)} Crystal growth of the reflective film due to the heating process and irregular reflection due to generation of hillocks. This is due to the ease of crystal growth, that is, heat resistance.
(2) Deterioration of the surface due to chemical reaction, oxidation, hydroxylation, etc. between the substance in the atmosphere and the reflective film when left unattended. This is due to weatherability.
[0033]
Hereinafter, the Ag alloy according to the present invention will be described.
As a material improvement method of (1), an element having a high effect of suppressing the crystal growth of Ag is added. As an element for suppressing the crystal growth of Ag, an element having a negative standard electrode potential is more effective than an element having a positive standard electrode potential. As a material improvement method of (2), an element which is chemically stable such that the standard electrode potential is positive is added. From the above, the improvement method of (1) and the improvement method of (2) contradict each other. In other words, there is a trade-off in material design, and improvement as one material means that it is difficult to achieve compatibility at a high level beyond the performance in which heat resistance and weather resistance are balanced. This technology does not attempt to improve heat resistance and weather resistance as a single material at a high level, but combines two materials, a material specialized in heat resistance and a material specialized in weather resistance, to achieve both. It is a technology that makes use of the strengths and compensates for the weaknesses.
[0034]
The lower layer is provided with an Ag alloy having high heat resistance, with the object of obtaining high heat resistance. Further, an Ag alloy having high weather resistance is provided on the upper portion thereof, and the laminated structure has at least two layers for the purpose of preventing the lower Ag alloy from being deteriorated. Since this technology aims to provide an Ag alloy laminate that makes use of the advantages of both the lower layer and the upper layer and compensates for the disadvantages, the material combined with the lower and upper layers is a material specializing in heat resistance. And combinations other than those specializing in weather resistance. For example, by combining a material specializing in etching property in the lower part and a material specializing in reflectivity in the upper part, it can be used as a laminate having both good etching property and high reflectivity. In addition, by combining a material specializing in low resistance in the lower part and a material specializing in weather resistance in the upper part, it can be used as a laminate having both low resistance and high weather resistance. With these applications, it can be used for various applications such as a reflector, an electrode, a wiring, a reflective electrode, a reflective wiring, and a semiconductor element.
[0035]
FIG. 2 shows a laminated structure of another type of silver alloy. The stacked structure of the silver-based alloy shown in FIG. 2 is a stacked structure in which a thin film made of a metal or an alloy is stacked on a substrate. At least one of the thin films is formed of a lower silver-based alloy thin film containing silver as a main component and at least one element having a negative standard electrode potential below the second component. An upper silver alloy thin film containing silver as a main component and containing only a metal having a positive standard electrode potential below the second component is formed. Alternatively, at least one thin film made of a metal or an alloy is provided as an intermediate layer on the lower silver-based alloy thin film, and only a metal having silver as a main component and a standard electrode potential less than or equal to the second component is provided on the intermediate layer. To form an upper silver-based alloy thin film. Further, the upper silver alloy thin film is formed thinner than the lower silver alloy thin film.
[0036]
The substrate, the lower silver-based alloy thin film, and the upper silver-based thin film are as described above. The intermediate layer may be provided to improve adhesion and affinity between the lower silver-based alloy thin film and the upper silver-based thin film. Further, a silver-based alloy thin film having a function separately from the lower silver-based alloy thin film and the upper silver-based thin film may be used. Examples of the composition of the intermediate layer include Ag-Pd, Ag-Cu, and Ag.
[0037]
In addition, the SiO 2 film is formed to such an extent that the reflectivity and the corrosion resistance of the upper silver alloy thin film are not reduced. ₂ , Al ₂ O ₃ At least one of them can be added. The upper silver alloy thin film has a thickness of 10 nm or more.
[0038]
Note that a protective layer for enhancing protection from a special atmosphere may be formed on the outermost layer of the laminated structure.
[0039]
The lower silver-based alloy thin film is a silver-zinc-palladium-copper alloy containing 50 atomic% or more of silver, which has poor heat resistance but excellent heat resistance, and the upper silver-based alloy thin film has poor heat resistance but poor heat resistance. It is preferable to use a silver-palladium-based alloy or a silver-palladium-copper-based alloy containing 50 atomic% or more of silver, which has excellent properties. The reflectances are both high.
[0040]
As a modification of the laminated structure of FIG. 2, the laminated structure shown in FIG. 3 may be used. That is, a base layer may be provided for the purpose of improving the adhesion between the substrate and the laminated structure. As the underlayer, Si, Ta, Ti, Mo, Cr, Al, ITO, IrO ₂ , ZnO, SiO ₂ , TiO ₂ , Ta ₂ O ₅ , ZrO ₂ Etc. can be exemplified. The intermediate layer may be provided in multiple layers as shown in FIG.
[0041]
Hereinafter, as a material improvement method, an element having a high effect of suppressing the crystal growth of Ag is added. As an element for suppressing the crystal growth of Ag, an element having a negative standard electrode potential is more effective than an element having a positive standard electrode potential. An example is shown as a result of this improvement by the laminated structure.
[0042]
【Example】
A reflection film was formed on a glass substrate. In other words, after the surface of the glass substrate is subjected to pretreatment by a conventional method, Ag-Pd-Cu-Zn (AZPC) is 96.26-0.26-0.58-2.9 at% as the first coating layer. A lower silver-based alloy thin film having a certain composition was formed by a sputtering method using an Ag-Pd-Cu-Zn alloy target. Next, an upper silver-based alloy thin film having a composition of 98.07-0.87-1.06 at% of Ag-Pd-Cu (APC) was formed on the surface of the lower silver-based alloy thin film as a second coating layer, It was formed by a sputtering method using a Pd-Cu alloy target. The thickness of the coating at this time was 200 nm for the first coating layer and 10 nm for the second coating layer to produce a total of 210 nm (Example 1-1). Further, a first covering layer having a thickness of 200 nm and a second covering layer having a thickness of 30 nm was manufactured to have a total of 230 nm (Example 1-2). As a comparative example, the same test was performed for a case where only the first coating layer AZPC was a single layer and a case where only the second coating layer APC was a single layer, and compared. The thickness of each of the AZPC single layer and the APC single layer for comparison was 200 nm for the heat resistance test, and 10 nm and 30 nm for the heat resistance test after the weather resistance test or the weather resistance test.
[0043]
The sputtering conditions at this time are as follows. The film was formed by Rf magnetron sputtering at a film forming pressure of 0.3 Pa and a film forming temperature of room temperature.
[0044]
The following evaluation test was performed on the reflection film thus prepared. The test conditions were as follows. (1) Immediately after film formation, (2) Weather resistance test by leaving in a clean room atmosphere of 50% humidity for 72 hours, (3) Heat resistance test by holding at 250 ° C. for 1 hour, (4) After performing (2) Heat resistance test after the weather resistance test performed in 3). As an evaluation method of (1) and (3), the surface state was observed by an atomic force microscope (AFM). Moreover, as an evaluation method of (1), (2), and (4), the reflectance was measured at wavelengths of 700 nm, 550 nm, and 400 nm.
[0045]
The AFM image of (1) is shown in FIG. The AFM image of (3) is shown in FIG. As a comparative example, an AFM image obtained by performing (2) on the APC single layer is shown in FIG. 6, and an AFM image obtained by performing (2) on the AZPC single layer is shown in FIG. From these results, it was found that the heat resistance of the APC single layer was not sufficient, and that the thin film of APC formed on the AZPC of the present example maintained the same heat resistance as the AZPC single layer.
[0046]
Next, Table 8 shows the reflectance measurement results of (1). Table 9 shows the reflectance measurement results of (2). Table 10 shows the measurement results of the reflectance of (4). In addition, Table 11 shows the amount of change, which is the difference Δ value between the reflectances of (2) and (1).
[Table 8]

[Table 9]

[Table 10]

[Table 11]

[0047]
From Tables 8 to 10, it was found that, compared to the AZPC single layer, the thin layer of the APC of the present example maintained the same or higher weather resistance as the APC single layer. In addition, it was found that the heat resistance after the weathering test was superior when the APC was thinly formed on the AZPC in the present example as compared with the APC single layer and the AZPC single layer.
[0048]
According to FIGS. 4 to 7 and Tables 8 to 11, the heat resistance and the weather resistance of the AZPC of the present embodiment are superior to that of the AZPC in that the APC is formed thinner than the APC single layer and the AZPC single layer. I knew it was there.
[0049]
This is because the upper silver-based alloy thin film with high weather resistance is laminated on top of the lower silver-based alloy thin film with high heat resistance, so that the metal with a negative standard electrode potential contained in the lower silver-based alloy undergoes chemical reaction, This is because a protection from a substance that causes deterioration such as oxidation and hydroxylation suppresses a decrease in reflectance.
[0050]
In addition, most of the thickness of this laminated structure is made of a heat-resistant lower silver-based alloy, which minimizes the crystal growth of the entire laminated structure and protects the upper weather-resistant upper silver-based alloy thinly on top of it. This is because by providing the layer, the lower silver-based alloy is isolated from a substance that may be deteriorated, thereby suppressing a decrease in reflectance due to deterioration of the surface.
[0051]
(Comparative Example 4)
Further, the thickness of the lower silver-based alloy thin film is 30 nm, and the thickness of the upper silver-based alloy thin film is 30 nm.
A laminated structure of a silver-based alloy thin film was prepared in the same manner as in Example 1-2 except that the thickness was 200 nm, and Comparative Example 3 was obtained. Comparative example 4 had the same performance as the example in initial characteristics after film formation, and there was no problem. However, comparative example 4 was inferior in heat resistance to example 1-2.
[0052]
(Comparative Example 5)
A reflection film was formed on a glass substrate. That is, after performing a pretreatment on the glass substrate surface by an ordinary method, a lower silver-based alloy thin film having a composition in which Ag-Pd-Cu is 98.07-0.87-1.06 at% is used as the first coating layer. And a sputtering method using an Ag-Pd-Cu alloy target. Next, an upper silver-based alloy thin film having a composition of 96.29-0.26-0.58-2.9 at% of Ag-Pd-Cu-Zn was formed as a second coating layer on the surface of the lower silver-based alloy thin film. And a sputtering method using an Ag-Pd-Cu-Zn alloy target. The thickness of the coating at this time was 200 nm for the lower silver-based alloy thin film and 30 nm for the upper silver-based alloy thin film. The thickness of the layered structure of the silver-based alloy was 230 nm. The film was formed at a film forming pressure of 0.5 Pa and a film forming temperature of 25 ° C. using a magnetron sputtering apparatus. Comparative Example 5 had the same performance as Example 1 with respect to the initial characteristics after film formation, and there was no problem. However, Comparative Example 5 was inferior to Example 1 in both weather resistance and heat resistance.
[0053]
Note that a lower silver-based alloy thin film having a silver alloy composition shown in Table 4, that is, a lower silver-based alloy thin film containing silver as a main component and at least one element having a negative standard electrode potential below the second component was used. When these were prepared and laminated, the weather resistance was insufficient.
[0054]
In addition, two kinds of upper silver-based alloy thin films shown in Tables 5 to 7, that is, upper silver-based alloy thin films containing silver as a main component and only a metal having a positive standard electrode potential below the second component are prepared. When these were laminated, heat resistance was insufficient.
[0055]
AZPC will be described.
The following can be exemplified as the composition of the lower silver-based alloy thin film.
Silver alloy with excellent corrosion resistance, with silver as the main component, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, nickel, palladium, platinum , A silver alloy containing at least one element selected from the group consisting of copper, gold, zinc, aluminum, gallium, indium, silicon, germanium and tin.
A silver alloy with high reflectivity, containing silver as a main component, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, nickel, palladium A silver alloy containing at least one element selected from the group consisting of platinum, copper, gold, zinc, aluminum, gallium, indium, silicon, germanium and tin.
A silver alloy having low electrical resistance characteristics, mainly composed of silver, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, nickel , Palladium, platinum, copper, gold, zinc, aluminum, gallium, indium, silicon, germanium and tin are silver alloys containing at least one element selected from the group consisting of:
Silver alloy with excellent heat resistance, with silver as the main component, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, nickel, palladium, A silver alloy containing at least one element selected from the group consisting of platinum, copper, gold, zinc, aluminum, gallium, indium, silicon, germanium, and tin.
The silver alloy described above is a silver alloy characterized in that the content of at least one type of each element is 0.1 atomic percent or more and 8.0 atomic percent or less.
A silver alloy having excellent corrosion resistance, containing silver as a main component and one element selected from the group consisting of zinc, nickel, tin and indium, and titanium, zirconium, hafnium, vanadium, niobium, and tantalum. Containing at least one element selected from the group consisting of chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, palladium, platinum, copper, gold, aluminum, gallium, silicon, and germanium. It is a characteristic silver alloy.
A silver alloy having high reflectivity, containing silver as a main component and one element selected from the group consisting of zinc, nickel, tin and indium, and titanium, zirconium, hafnium, vanadium, and niobium. Containing at least one element selected from the group consisting of tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, palladium, platinum, copper, gold, aluminum, gallium, silicon, and germanium It is a silver alloy characterized by the above.
A silver alloy having electrically low resistance characteristics, containing silver as a main component and one element selected from the group consisting of zinc, nickel, tin and indium, and titanium, zirconium, hafnium, and vanadium. , Niobium, tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, palladium, platinum, copper, gold, aluminum, gallium, silicon, and at least one element selected from the group consisting of germanium It is a silver alloy characterized by containing.
A silver alloy having excellent heat resistance, containing silver as a main component and one element selected from the group consisting of zinc, nickel, tin and indium, titanium, zirconium, hafnium, vanadium, niobium, Contain at least one element selected from the group consisting of tantalum, chromium, molybdenum, tungsten, iron, ruthenium, cobalt, rhodium, iridium, palladium, platinum, copper, gold, aluminum, gallium, silicon, and germanium It is a silver alloy characterized by the following.
In the silver alloy, the content of the one element is 0.1 atomic percent or more and 8.0 atomic percent or less, and the content of the at least one element is 0.1 atomic percent or more and 8.0 atomic percent. % Or less.
A silver alloy having excellent heat resistance, containing silver as a main component, containing zinc or indium in an amount of 0.1 to 8.0 atomic percent, and containing copper in an amount of 0.1 to 8.0 atomic percent. The silver alloy contains 0.1 to 8.0 atomic percent of palladium.
A silver alloy having high reflectivity, containing silver as a main component, containing zinc or indium in an amount of 0.1 to 8.0 atomic percent, and containing copper in an amount of 0.1 to 8.0 atomic percent. The silver alloy contains 0.1% by weight or less and 8.0% by atom or less of palladium.
A silver alloy having electrically low resistance characteristics, containing silver as a main component, containing zinc or indium in an amount of 0.1 to 8.0 atomic percent, and containing copper in an amount of 0.1 to 8.0 atomic percent. A silver alloy containing 0 atomic percent or less, and further containing 0.1 atomic percent or more and 8.0 atomic percent or less of palladium.
A silver alloy having excellent corrosion resistance, comprising silver as a main component, containing zinc or indium in an amount of 0.1 atomic percent or more and 8.0 atomic percent or less, and containing copper in an amount of 0.1 atomic percent or more and 8.0 atomic percent or less. A silver alloy containing 0.1 atomic percent or more and 8.0 atomic percent or less of palladium.
A silver alloy having excellent heat resistance, containing silver as a main component, containing zinc in a range of 3.0 atomic percent to 8.0 atomic percent, and containing copper in a range of 0.3 atomic percent to 1.7 atomic percent. And a silver alloy containing 0.2 to 3.0 atomic percent of palladium.
A silver alloy having excellent corrosion resistance, containing silver as a main component, containing zinc in an amount of 0.1 to 8.0 atomic percent, copper in an amount of 0.1 atomic percent or more, and palladium in an amount of 0.1 atomic percent or more. It is a silver alloy characterized by containing at least 2 atomic percent.
A silver alloy having excellent heat resistance and corrosion resistance, containing silver as a main component, containing zinc in a range of 3.0 to 8.0 atomic percent, and containing copper in a range of 0.3 to 1.7 atomic percent. A silver alloy containing the following, and further containing 0.2 atomic percent or more of palladium.
The lower silver-based prototype alloy thin film made of the silver alloy and the silver-based alloy laminated structure of the present application become a reflective LCD reflective plate or a reflective wiring electrode that suppresses yellowing of reflected light.
The lower silver-based prototype alloy thin film made of the silver alloy and the silver-based alloy laminated structure of the present application can also be used as an optical recording medium.
An electromagnetic wave shield comprising a substrate made of an elastomer material and an electromagnetic wave shielding film formed on the substrate, wherein the electromagnetic wave shielding film is a laminated structure of the silver-based alloy according to the present invention. .
An electromagnetic wave shield comprising a substrate made of a plastomer material and an electromagnetic wave shielding film formed on the substrate, wherein the electromagnetic wave shielding film is a laminated structure of the silver-based alloy according to the present invention. .
The electromagnetic wave shielding film may be composed of one film or a plurality of films.
The underlayer is at least one selected from the group consisting of indium tin oxide, iridium oxide, zinc oxide, silicon dioxide, titanium oxide, tantalum pentoxide, zirconium oxide, silicon, tantalum, titanium, molybdenum, chromium, and aluminum. It is a thin film formed using a plurality of materials or a material containing at least one of the one or more materials.
A metal material for an electronic component, comprising the silver alloy.
Each of the wiring pattern, the electrode and the contact is formed by etching with a solution.
Each of the wiring pattern, the electrode, and the contact is formed by etching in a gas atmosphere.
The wiring pattern, the electrodes and the contacts were formed by mixing one or more of tungsten, tantalum, molybdenum, indium oxide, tin oxide, titanium nitride, silicon dioxide, silicon nitride, titanium oxide, and niobium oxide. This is formed on the underlayer.
The wiring pattern, the electrode and the contact are each formed directly on a glass or plastomer material substrate.
By forming the metal film made of the silver alloy on a base made of tungsten, tantalum, molybdenum, indium / tin oxide, titanium nitride, silicon dioxide, or silicon nitride, a wiring pattern, an electrode, and a contact A method for processing a layered structure of a silver-based alloy, characterized by forming at least one of the following.
Forming a metal film made of the silver alloy directly on a glass or plastomer material substrate to form at least one of a wiring pattern, an electrode, and a contact point; Is the way.
An electro-optical component having at least one of a reflective film, a wiring pattern, and an electrode formed of the silver alloy.
The laminated structure of the lower silver-based alloy exemplified above and the silver-based alloy of the present application solves the following problems.
Conventional metal materials have not always been sufficiently developed with respect to materials having excellent corrosion resistance, high reflectance, low electrical resistance, and excellent heat resistance.
Further, in the conventional reflection type liquid crystal display panel, when manufacturing or using the reflection type LCD reflection plate, it may react with sulfur, oxygen, moisture and the like in the air, thereby deteriorating the reflection characteristics, There is a problem of yellowing that the chromaticity of the reflected light changes to yellow.
Further, it cannot be said that a thin film formed of Al or an Al alloy still has a sufficient reflectance depending on the use of the optical recording medium. Further, there has not yet been developed an alloy material having sufficient characteristics with respect to weather resistance, reflectance and transmittance when a thin film is formed.
In addition, the electromagnetic wave shield using the conventional elastomer material has problems in followability to bending into a complicated shape, corrosion resistance, weather resistance, abrasion resistance, and the like, and is not adopted (applied) as an EMC material at all. And so on.
Further, in the electromagnetic wave shield using the conventional plastomer material substrate, electromagnetic wave shielding, infrared shielding, transparency, invisibility, corrosion resistance, weather resistance and wear resistance are not sufficiently satisfied, There was a problem that it was not adopted (applied) at all as an EMC material.
Further, in conventional electronic devices and electronic parts, wiring materials, electrode materials, and contact materials that are not sufficiently low in electrical resistivity and excellent in workability have not been developed.
As a reflection film for reflecting infrared rays and heat rays for building glass, a reflection film formed of Ag, Al, or an alloy material containing any one of these elements as a main component is widely known. However, these reflection films are not necessarily excellent in heat resistance.
For example, Ag and Al do not have high heat resistance to heat, and the surface portion is easily diffused at a specific temperature. For example, when manufacturing a reflector for a liquid crystal display element, a temperature atmosphere during the manufacturing process is required. Is limited. Furthermore, in the case of infrared and heat ray reflective films for building material glass, when exposed to high temperatures in the summer in the air, the reflective film itself chemically changes (discolors). There was a problem with stability.
Au is known as a material having a high reflectivity other than Ag and Al. However, since Au is very expensive, it is practically used from the viewpoint of cost in order to use it as a reflective film for window glass of building materials. It is determined that sex is poor.
In addition, for Al, which has high reflectivity, is very inexpensive in terms of cost, and has high practicality, when a resin substrate such as PMMA or silicone resin is used, gas deposited from the resin substrate is used. There is a risk of causing a chemical reaction on the components. For this reason, the method is effective only for a substrate made of a material having a low gas releasing action, which not only limits the material of the substrate but also raises concerns about the chemical stability of the material when making contact with a resin. Anxiety and challenges remain.
Further, Ag has the highest optical reflectivity among many metal elements in the optical wavelength range referred to as the visible and infrared regions of 400 to 4000 nm, and thus has excellent characteristics as a film characterized by high reflectivity. Is considered to be held. However, since self-diffusion energy for heat is active, there is a problem that a change with time occurs when heat is applied. For this reason, even if the heat is temporarily applied at about 100 ° C., a diffusion phenomenon occurs on the surface portion, and the gloss inherent in Ag is lost and the silver becomes cloudy. In other words, the characteristic of Ag, which is a high reflectivity, is greatly reduced.
Further, when a reflective film is formed on a glass or resin substrate, if Ag is left in the air, it absorbs moisture (mainly water) in the air and turns yellow, so that the reflectance is low. There are problems such as the high characteristic of Ag being impaired. Therefore, it cannot maintain the original characteristic of high reflectance, and cannot be said to be excellent in weather resistance.
The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a silver alloy having excellent corrosion resistance. Another object of the present invention is to provide a silver alloy having a high reflectance. Another object of the present invention is to provide a silver alloy having electrically low resistance characteristics. Another object of the present invention is to provide a silver alloy having excellent heat resistance.
Further, another object of the present invention is to provide a sputtering target, a reflective plate for a reflective LCD, a reflective wiring electrode, a thin film, and a method for manufacturing the same, which suppress yellowing of reflected light.
It is another object of the present invention to provide an optical recording medium that maintains high reflectance as compared with Ag and has improved weather resistance.
Another object of the present invention is to provide an optical recording medium in which the weather resistance of the translucent reflective film is improved and higher reliability is obtained.
Another object of the present invention is to provide flexibility and shape flexibility (bending followability to a complicated shape), to be widely applied mainly as an EMC countermeasure material, and even in a high-temperature and high-humidity environment. The material stability of weather resistance such as high electromagnetic wave shielding ability is continuously maintained, and the bonding property (adhesion) with the elastomer material substrate is more effectively strengthened and higher. An object of the present invention is to provide an electromagnetic wave shield capable of obtaining reliability.
Another object of the present invention is to provide electromagnetic shielding and infrared shielding properties, transparency, invisibility, corrosion resistance, weather resistance and abrasion resistance, etc. In addition, the material stability of weather resistance, such as high electromagnetic wave shielding ability is continuously maintained even in a high-temperature and high-humidity environment, is remarkably improved, and the bonding property (adhesion) with a plastomer material substrate is improved. An object of the present invention is to provide an electromagnetic wave shield that is more effectively strengthened and has higher reliability.
Further, another object of the present invention is to provide a metal material for electronic components, a wiring material, an electronic component using a silver alloy, which has a lower electrical resistivity than the conventional one, and is stable and excellent in workability. An object is to provide an apparatus, a method of processing a metal film, and an electronic optical component.
Another object of the present invention is to use a highly heat-resistant reflective film having high reliability while maintaining the high optical properties of Ag itself, further improving the material stability of Ag. To provide a laminated body and a building material glass.
Ag-Zn-Pd-Cu-based silver alloy is a silver alloy having at least one property of excellent corrosion resistance, high reflectance, electrically low resistance and excellent heat resistance, and containing Ag as a main component. The alloy contains 0.1 at% or more and 8.0 at% or less of Zn, 0.1 at% or more and 8.0 at% or less of Cu, and further contains 0.1 at% or more and 8.0 at% or less of Pd. More preferably, the content of Zn is 0.1 at% or more and 5.0 at% or less, the content of Cu is 0.1 at% or more and 5.0 at% or less, and the content of Pd is 0.1 at% or more and 5.0 at% or less. 0 at% or less.
Ag-In-Pd-Cu-based silver alloy is a silver alloy having at least one property of excellent corrosion resistance, high reflectance, electrically low resistance and excellent heat resistance, and containing Ag as a main component, The alloy contains 0.1 at% or more and 8.0 at% or less of In, Cu contains 0.1 at% or more and 8.0 at% or less, and further contains Pd of 0.1 at% or more and 8.0 at% or less. More preferably, the content of In is 0.1 at% or more and 5.0 at% or less, the content of Cu is 0.1 at% or more and 5.0 at% or less, and the content of Pd is 0.1 at% or more and 5.0 at% or less. 0 at% or less.
The Ag-Zn-Pd-Cu-based silver alloy is a silver alloy having excellent heat resistance, containing Ag as a main component, containing Zn in a range of 3.0 at% to 8.0 at%, and containing Cu in an amount of 0.1 at% or less. The alloy contains 3 at% or more and 1.7 at% or less, and further contains 0.2 at% or more and 3.0 at% or less of Pd. The content of Cu in the silver alloy having particularly preferable heat resistance is 0.3 at% or more and 0.5 at% or less.
The Ag-Zn-Pd-Cu-based silver alloy is a silver alloy having excellent corrosion resistance, containing Ag as a main component, containing Zn at 0.1 at% or more and 8.0 at% or less, and Cu at 0.1 at% or less. % Or more, and further contains 0.2 at% or more of Pd.
The Ag-Zn-Pd-Cu-based silver alloy is a silver alloy having excellent heat resistance and corrosion resistance, containing Ag as a main component, containing Zn at 3.0 at% or more and 8.0 at% or less, and containing Cu at at least 3.0 at%. This alloy contains 0.3 at% or more and 1.7 at% or less, and further contains 0.2 at% or more of Pd. The content of Cu in the silver alloy having particularly preferable heat resistance is 0.3 at% or more and 0.5 at% or less.
A thin film may be formed by producing a silver alloy target having the above composition. In the case of a sputtering target, an ingot made of the above-described silver alloy is manufactured by a casting method. Another method for manufacturing a sputtering target will be described. Examples of the method for producing the sputtering target material include a melting method in an air atmosphere and a melting method in a vacuum. In the case of manufacturing the above-mentioned silver alloy by a melting method, first, a base mother alloy is prepared, and Ag is additionally added thereto, and the metal contained in the alloy is adjusted so that Ag becomes a specified amount. The content shall be adjusted.
The case of performing in air will be described. First, a master alloy is produced by melting and mixing the above-described silver alloy by arc melting in an argon (hereinafter, Ar) atmosphere (400 to 600 Torr).
Next, Ag is melted in a high-frequency melting furnace. The amount of Ag at this time is defined as the amount obtained by subtracting the amount of Ag in the master alloy from the total dissolved amount. The melting temperature at this time is, for example, 1000 to 1500 ° C., for example, a 0.1 to 0.2 liter parallel graphite crucible is used.
After complete melting, an antioxidant is introduced to suppress and prevent solid solution with oxygen during melting. As the antioxidant, borax, sodium borate, lithium borate, carbon and the like can be used.
In a completely melted state, the mixture is left for about 1 hour, and the above-mentioned mother alloy is added and further melted for 0.5 to 1 hour. The melting temperature at this time is, for example, 1050 to 2000 ° C.
Next, the molten material is poured into a Fe mold in which, for example, alumina or talc is applied to the inner surface. The Fe mold is previously heated to about 300 to 500 ° C. in an electric furnace or the like in order to prevent shrinkage cavities.
The melt in the mold is cooled and solidified, the ingot is removed from the mold and cooled to room temperature. Next, the uppermost feeder portion of the ingot is cut and removed, and the ingot is rolled by a rolling mill to produce a 90 mm × 90 mm × 8.1 mm plate-shaped alloy.
Thereafter, a heat treatment is performed for about 1 to 1.5 hours in a state where Ar gas is sealed in an electric furnace at a temperature of, for example, 400 to 500 ° C., and thereafter, warpage is corrected by a press machine.
Thereafter, the product is wire-cut into a product shape, and the entire surface of the product is polished using a water-resistant abrasive paper to adjust the surface roughness. Finally, an Ag alloy sputtering target material can be produced.
The dissolving method in the air has been described above, but other dissolving methods can be used. Hereinafter, the case of dissolving in an Ar atmosphere will be described.
First, in an Ar atmosphere (400 to 600 Torr), the above-described silver alloy is melted and mixed by arc melting to prepare a master alloy.
Next, the above-mentioned mother alloy and Ag are melted in a high frequency melting furnace. The amount of Ag at this time is defined as the amount obtained by subtracting the amount of Ag in the master alloy from the total dissolved amount.
The crucible containing the mother alloy and Ag is placed in a high-frequency melting furnace and evacuated. After evacuating to a degree that does not involve oxygen, the melting furnace is set to an Ar atmosphere (100 to 600 Torr) and then melting is started.
The melting temperature at this time is, for example, 1050 to 1400 ° C., and the crucible is, for example, a 0.1 to 0.2 liter normal graphite crucible.
Next, the molten material is poured into a Fe mold in which, for example, alumina or talc is applied to the inner surface.
The Fe mold is previously heated to about 300 to 500 ° C. in an electric furnace or the like in order to prevent shrinkage cavities.
The melt in the mold is cooled and solidified, the ingot is removed from the mold and cooled to room temperature.
Next, the uppermost feeder portion of the ingot is cut and removed, and the ingot is rolled by a rolling mill to produce a 90 mm × 90 mm × 8.1 mm plate-shaped alloy.
Thereafter, a heat treatment is performed for about 1 to 1.5 hours in a state in which Ar gas is sealed at 400 to 500 ° C. in an electric furnace, for example, and then a warp is corrected by a press machine.
Thereafter, the product is wire-cut into a product shape, and the entire surface of the product is polished with a water-resistant abrasive paper to adjust the surface roughness. Finally, the silver alloy sputtering target material of the present invention can be produced.
As described above, when producing the sputtering target material of the silver alloy of the present invention, even when adding Zn and other elements X to Ag and melting it, the conventional easy method is applied. It has great advantages in terms of price and recipe.
Zn, Ni, Sn and In are contained for the purpose of preventing chloride, sulfurization and deoxidation (antioxidation) and for preventing migration (prevention of ionization). Pd is contained in eutectic with Ag. This is because it is considered that the corrosion resistance is further increased in order to make an alloy. The inclusion of, for example, Cu in each of the at least one element is intended to reduce electric resistance, increase workability of an Ag alloy, prevent migration, and the like.
In addition, it has been confirmed that a practically high reflectance can be obtained from the silver alloy as shown in Tables 13 and 14 in the reflectance measurement described below. Further, it has been confirmed that the resistance can be electrically reduced as shown in Table 12 in the measurement of the resistance value described later.
[Table 12]

The lower silver-based alloy thin film and the upper silver-based alloy thin film of the present application are formed by, for example, an RF (AC) magnetron sputtering method in a sputtering apparatus using the sputtering target. Therefore, a reflective LCD reflector made of any of these thin films can stably provide uniform characteristics even when viewed microscopically.
The reflective plate for a reflective LCD is formed by the thin film made of the silver alloy described above. For this reason, it is possible to suppress the reaction with sulfur, oxygen, moisture, and the like in the air at the time of manufacturing or using the reflection plate for the reflection type LCD. Therefore, it is possible to suppress yellowing in which the chromaticity of the reflected light changes and the color changes to yellow. Further, the reflectance of the reflected light can be increased (that is, the reflectance of the reflected light can be improved), and a high reflectance can be stably secured.
Next, a reflective wiring electrode and a method of manufacturing the same according to a fourth embodiment of the present invention will be described. The reflective wiring electrode is made of any of the above-mentioned thin films.
The thin film is formed by an RF (alternating current) magnetron sputtering method in a sputtering apparatus using the sputtering target, and then processed into a predetermined shape by etching. The reflective wiring electrode made of this thin film can stably provide uniform characteristics even when viewed microscopically. Further, the thin film can be etched with an etching solution containing phosphoric acid, for example. Examples of the phosphoric acid-based etchant include H ₃ PO ₄ + HNO ₃ + CH ₃ COOH can be used.
Further, each of the reflection plate and the reflection wiring electrode for the reflection type LCD has a sufficient adhesion to a base such as a quartz glass substrate.
In the above embodiment, the thin film is formed by the sputtering method, but the thin film can be formed by another film forming method such as an evaporation method, a CVD method, and a plating method.
An optical recording medium made of an Ag-Pd-Cu-Zn alloy obtained by adding a predetermined amount of Pd, Cu, Zn to Ag, or an Ag-Pd-Cu-In alloy obtained by adding a predetermined amount of Pd, Cu, In to Ag. The reflectance for a laser beam having a wavelength of 400 nm and the reflectance for a laser beam having a wavelength of 550 nm were measured when an optical recording medium was produced by forming a thin film for use, that is, a reflective film. Table 14 shows the measurement results in this case. As a comparative example, the reflectance of a thin film of an Ag-0.5 at% Pd-1.0 at% alloy containing Ag as a main component, 0.5 at% of Pd and 1.0 at% of Cu was measured.
[Table 13]

From the measurement results shown in Table 13, when a thin film of an optical recording medium is formed using a sputtering target material of Ag alloy containing Pd, Cu, Zn or In in Ag, a high reflection which is practically desirable. It can be seen that the rate is obtained.
Next, after the thin film shown in Table 13 was subjected to a heat treatment at a temperature of 250 ° C. for one hour, the reflectance for a laser beam having a wavelength of 400 nm and the reflectance for a laser beam having a wavelength of 550 nm were measured. Table 14 shows the measurement results in this case.
[Table 14]

The measurement results shown in Table 14 indicate that a practically desirable high reflectance is obtained.
Further, Ag is easily bonded to sulfur, so if left in the air for a long time, Ag ₂ It becomes S and turns black. As a result, the optical characteristics of the Ag thin film deteriorate. Ag also reacts violently with chlorine to become AgCl and becomes cloudy. As a result, the optical characteristics of the Ag thin film deteriorate. However, Ag is a substance that is relatively stable to oxygen, hydrogen, or water. On the other hand, Zn, In, Sn, and Ni have a deoxidizing effect (antioxidation), an action of sulfurization, and a prevention of chloride, and are chemically stable substances against sulfur and chlorine.
According to the Ag alloy sputtering target, chlorine, hydrogen, oxygen, sulfur, the atmosphere required in the air or a non-metallic element studied in a special environment or the environment required when employed in an optical recording medium, It is possible to realize high weather resistance under an atmosphere.
The corrosion resistance test (5% NaCl immersion test) and the results will be described. As a sample of the 5% NaCl immersion test, a sample in which an Ag alloy having a composition (at% indicated) shown in the table was formed on a polycarbonate substrate was used. In the 5% NaCl immersion test, the sample was immersed in a 5% -concentration saline at room temperature, and then visually confirmed after 3 minutes, 3 hours, and 24 hours.
As shown in Table 16, when the content of Pd in the Ag-Zn-Cu-Pd alloy was 0.1 at%, a slight white color was observed after 24 hours, but the content of Pd was 0.2 at%. %, There was no change even after 24 hours. Therefore, it was confirmed that the content of Pd should be 0.2 at% or more in order to obtain corrosion resistance.
As shown in Table 17, when the corrosion resistance test was performed on the samples in which the content of Cu in the Ag-Zn-Cu-Pd alloy was changed from 0 at% to 5.0 at%, all the samples after 24 hours passed. No change was observed. Therefore, in this alloy, it was confirmed that the composition of Cu did not affect the corrosion resistance.
As shown in Table 15, when the corrosion resistance test was performed on samples in which the content of Zn in the Ag—Zn—Cu—Pd alloy was changed from 0.8 at% to 8.0 at%, all samples passed for 24 hours. No later changes were observed. Therefore, in this alloy, it was confirmed that the composition of Cu did not affect the corrosion resistance.
[Table 15]

[Table 16]

[Table 17]

When the substrate is an elastomeric material, examples of the material include silicone rubber, natural rubber, chloroprene rubber, and EPDM (rubber-like terpolymer of ethylene / propylene and diene).
When the substrate is a plastomer material, examples of the material include a plastic film and engineering plastic, and the main types include polyamide, polycarbonate, polyacetal, polybutylene terephthalate, and modified polyphenylene ether.
As a material of the adhesion promoting base film, it is materially stable with respect to a substrate made of oxygen or various materials, and considering adhesion between the substrate and at least the electromagnetic wave shielding film made of the silver alloy, Si, Ta , Ti, Mo, Cr, Al, ITO, IrO ₂ , ZnO, SiO ₂ , TiO ₂ , Ta ₂ O ₅ , ZrO ₂ It is preferably formed using one or more materials selected from the group consisting of the above, or a material containing at least the one or more materials as a main component.
It has also been confirmed that the silver alloy described above has high chemical stability with respect to various elastomer materials such as silicone rubber, natural rubber, chloroprene rubber, and EPDM, and is not limited to the substrate material made of the elastomer material. I have.
In addition, the silver alloy described above has high chemical stability against various plastomer materials such as polyamide, polycarbonate, polyacetal, or polybutylene terephthalate, and modified polyphenylene ether, and is not limited to a substrate material made of a plastomer material. Has also been confirmed.
Further, as a base film for promoting adhesion of a substrate made of various elastomer materials, Si, Ta, Ti, Mo, Cr, Al, ITO, ZnO, SiO ₂ , TiO ₂ , Ta ₂ O ₅ , ZrO ₂ Is desirable.
The reason is that a substrate made of silicone rubber, natural rubber, chloroprene rubber or EPDM generates a very large amount of gas in the case of a specific purity or material, a metal reacts strongly with the generated gas, and a silver alloy is used. This is because it is difficult to say that it is appropriate because it is highly likely that a thin film is brought into close contact with the thin film and that a reaction passivation film (for example, an oxide film or the like) is formed at the interface.
The reflectance to light having a wavelength of 550 nm was measured on a thin film of the test sample (as it was immediately after film formation). Next, the test sample was placed in an oven in the atmosphere for about 1 hour, and the reflectance to light having a wavelength of 550 nm was measured. At this time, a resistance heating method was adopted as a heating method of the oven, and the heating temperature was set to 250 ° C. and the heating rate was set to 20 ° C./min. Then, the rate of change in reflectance after heating for 1 hour with respect to the reflectance of the thin film immediately after film formation was calculated. Tables 18 and 19 show the test results. In the heat resistance test described below, the silver alloy obtained a result such as excellent heat resistance in which the decrease in reflectance after annealing was small, as shown in Tables 18 and 19. Further, in the corrosion resistance test, Table 12 was obtained. As shown in the above, good results were obtained for NaCl, and it was confirmed that the silver alloy was excellent in heat resistance and corrosion resistance.
[Table 18]

[Table 19]

[0056]
【The invention's effect】
According to the present invention, a laminated structure of a silver-based alloy having low electric resistance, corrosion resistance, heat resistance, workability, adhesion, and high reflectance all at a predetermined level or more can be provided. In other words, the present invention combines a material specialized for heat resistance and a material specialized for weather resistance to provide an Ag alloy having high heat resistance in the lower layer, thereby obtaining high heat resistance. Aim. Further, an Ag alloy having high weather resistance was provided on the upper portion thereof, thereby preventing the lower Ag alloy from being deteriorated. Further, according to the present invention, it can be used for various applications such as a reflection plate, an electrode, a wiring, a reflection electrode, and a reflection wiring.
[Brief description of the drawings]
FIG. 1 is a view showing one embodiment of a layered structure of a silver alloy according to an embodiment.
FIG. 2 is a diagram showing a second embodiment of the laminated structure of the silver alloy of the present embodiment.
FIG. 3 is a view showing a third embodiment of the silver alloy laminated structure of the present embodiment.
FIG. 4 is an image of a (1) initial surface AFM photograph of an example.
FIG. 5 is an image of an AFM photograph after the evaluation of (3) weather resistance of the example.
FIG. 6 is an AFM image obtained by performing (2) on an APC single layer of a comparative example.
FIG. 7 is an AFM image obtained by performing (2) on an AZPC single layer of a comparative example.
FIG. 8 shows a microscopic observation of the sample surface after adding Zn to 1.8-7.3 at% to Ag-0.5 at% Pd-1.0 at% Cu and performing an annealing test at 250 ° C. for 1 hour. 5 is an image of a photograph showing the result of the experiment.

Claims (17)

A lower silver-based alloy thin film is formed on a substrate, the lower silver-based alloy thin film containing silver as a main component and at least one element having a negative standard electrode potential below the second component. An upper silver-based alloy thin film containing only a metal whose standard electrode potential is positive below the second component is formed to be thinner than the lower silver-based alloy thin film. A laminated structure in which thin films made of a metal or an alloy are stacked on a substrate, wherein at least one of the thin films contains silver as a main component and at least one element having a negative standard electrode potential below the second component. Forming a lower silver-based alloy thin film, and forming an upper silver-based alloy thin film on the lower silver-based alloy thin film containing only a metal whose main component is silver and whose standard electrode potential is positive below the second component, or At least one thin film made of a metal or an alloy is provided as an intermediate layer on the lower silver-based alloy thin film, and only a metal having silver as a main component and a second component or less and having a positive standard electrode potential is provided on the intermediate layer. A laminated structure of a silver-based alloy, wherein an upper silver-based alloy thin film to be contained is formed, and the upper silver-based alloy thin film is formed thinner than the lower silver-based alloy thin film. The silver-based alloy laminated structure according to claim 1, wherein at least one of SiO ₂ and Al ₂ O ₃ is added to the upper silver-based alloy thin film. 4. The silver-based alloy laminated structure according to claim 1, wherein the upper silver-based alloy thin film has a thickness of 10 nm or more. The silver-based alloy according to claim 1, wherein the intermediate layer is an adhesion layer for enhancing affinity between the lower silver-based alloy thin film and the upper silver-based alloy thin film. Laminated structure. 6. The silver-based alloy laminated structure according to claim 1, wherein an underlayer for strengthening adhesion between the substrate and the laminated structure is formed on the substrate. 7. The silver-based alloy laminated structure according to claim 1, wherein a protective layer for enhancing protection from a special atmosphere is formed on the outermost layer of the laminated structure. 8. The silver-based alloy laminated structure according to claim 1, wherein said substrate is a glass substrate, a resin substrate, or a glass / resin laminated substrate. 9. The silver alloy according to claim 1, wherein the lower silver alloy thin film is a silver-zinc-palladium-copper alloy containing 50 atomic% or more of silver. Laminated structure of silver alloy. 7. The silver alloy according to claim 1, wherein the upper silver alloy thin film is a silver-palladium alloy or a silver-palladium-copper alloy containing 50 atomic% or more of silver. 10. The laminated structure of the silver-based alloy according to 7, 8 or 9. A silver-based alloy electrode having a laminated structure of the silver-based alloy according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. 11. A silver-based alloy wiring, wherein the silver-based alloy laminate structure according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 is patterned. A silver-based alloy reflective film having a laminated structure of the silver-based alloy according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. A silver-based alloy reflective electrode having a laminated structure of the silver-based alloy according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. A self-luminous display comprising the laminated structure of the silver-based alloy according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. A flat panel display comprising the silver-based alloy laminated structure according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. A semiconductor device comprising the stacked structure of the silver-based alloy according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

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