JP2004068092A

JP2004068092A - Hard carbon film coating member and film forming method

Info

Publication number: JP2004068092A
Application number: JP2002229781A
Authority: JP
Inventors: Takahiko Tanida; 貴彦谷田; Osamu Yamada; 修山田; Eiji Okuda; 英二奥田; Hideo Imoto; 秀夫猪本; Takeshi Hatayama; 健畑山; Hiroshi Yamashita; 博司山下
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2002-08-07
Filing date: 2002-08-07
Publication date: 2004-03-04
Anticipated expiration: 2022-08-07
Also published as: JP4284941B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a member having a hard carbon film of excellent adhesiveness to a base material formed thereon, and a method for forming the member. <P>SOLUTION: An intermediate layer is provided between a base material 2 and a hard carbon film layer 5 as an adhesive layer to the hard carbon film layer 5 on the base material 2. The intermediate layer comprises a substrate layer 2 formed of a thin film of metal selected from a group of IVa, Va, VIa, VIIa, VIIIa and IVb group elements, and a mixed layer 4 formed of carbide of metal elements selected from a group of IVa, Va, VIa, VIIa, VIIIa and IVb group elements. Adhesiveness of the base material to the hard carbon film is improved thereby. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は基材との密着性に優れた硬質炭素膜被覆部材の形成方法を提供するものである。
【０００２】
【従来の技術】
硬質炭素膜（ＤＬＣ）は硬度が高く、耐摩耗性がよく、また自己潤滑性に富み、アモルファス構造であることから表面粗さが非常に小さいため摩擦係数が非常に小さい。さらに、物質的に安定であり化学的な耐久性も高い。そのため古くから切削・加工用工具、金型、機械部品に利用されており、近年では磁気ディスク記録装置の記録面および磁気記録ヘッド表面やスピンドルモータの軸受け摺動部に用いる保護膜として一部利用されている。
【０００３】
一方で超鋼、ステンレス、樹脂などの基材上に硬質炭素膜を形成する場合、膜形成時に極めて大きな内部応力が発生し、変形能が極めて小さいことから基材との密着性が弱く、剥離し易いという欠点をもっている。こうした硬質炭素膜の基材との密着性を改善する技術として、これまでも基材との間に密着層として異種金属にて構成される中間層を設ける方法が提案されている。
【０００４】
例えば、特開２０００−１１９８４３、特開２００２−３６７９１においては２層からなる中間層を成膜した部材、特開平１０−２０３８９６においては下地層として金属元素を有し、第２層として金属と炭素が傾斜的に変化する構造を有する中間層を用いて密着力を向上させるための方法が提案されている。
【０００５】
【発明が解決しようとする課題】
しかしながら、これまで提案されている技術はあくまで、多層の中間層や炭素が傾斜的に変化する部材の構成を示しているのみであり、その量産に適した硬質炭素膜の製造方法を示しているのもではない。本発明はその問題点を鑑みてなされたものであり、生産性よく密着力の高い硬質炭素膜を提供するものである。
【０００６】
【課題を解決するための手段】
前記課題を解決するために、本発明の硬質炭素膜被覆部材は、基材に下地層と混合層からなる中間を介して硬質炭素膜を形成したものであり、下地層はＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族金属元素から選択され、混合層はＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族金属元素の炭化物または、ＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族金属元素と炭素の濃度が下地層側から硬質炭素膜層側に向かって段階的または連続的に変化していることを特徴とする。
【０００７】
本発明によれば、基材の材質によることなく容易に密着力の高い硬質炭素膜が被覆された部材を提供できる。
【０００８】
【発明の実施の形態】
本発明の請求項１記載の発明は、基材に中間層を介して硬質炭素膜が形成された部材であって、前記中間層は金属元素からなる下地層と、金属化合物からなる混合層を有することを特徴とする硬質炭素膜硬質炭素膜被覆部材としたものであり、硬質炭素膜を金属からなる下地層と金属化合物からなる混合層で構成される中間層を介して形成することによって硬質炭素膜被覆部材の密着力が向上する作用を有する。
【０００９】
本発明の請求項２に記載の発明は、請求項１に記載の硬質炭素膜硬質炭素膜被覆部材であって、前記下地層はＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族から選ばれる金属元素を少なくとも１つ用いて形成したことを特徴とする硬質炭素膜被覆部材としたものであり、下地層をＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族の金属元素から選ぶことによって下地と基材の密着力が向上する作用を有する。
【００１０】
本発明の請求項３に記載の発明は、請求項１〜２いずれかに記載の硬質炭素膜被覆部材であって前記混合層はＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族から選ばれる前記金属元素の炭化物で構成されることを特徴とする硬質炭素膜被覆部材としたものであり、混合層をＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族金属の炭化物としたことで下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１１】
本発明の請求項４に記載の発明は、請求項１〜３いずれかに記載の硬質炭素膜被覆部材であって、前記混合層は前記下地層側から硬質炭素層側に向かって金属と、炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜被覆部材としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１２】
本発明の請求項５に記載の発明は、内部を真空に保つことができる真空容器と、前記真空容器に原料ガスを供給するガス供給手段と、前記反応容器内に設置され基材を保持する基材支持台と、前記基材支持台に設置した基材と、蒸発源を有する硬質炭素膜形成方法であって、前記ガス供給手段から不活性ガスを供給し、前記蒸発源を蒸発させ基材上に下地層を形成するステップと、少なくとも炭化水素ガスと不活性ガスの混合ガスを前記ガス供給手段より供給し、前記混合ガス中で前記蒸発源を蒸発させ、前記基材上に前記蒸発源の炭化物からなる混合層を形成するステップと、前記ガス供給手段から少なくとも炭化水素ガスを供給し、更に前記試料台に高周波電圧を印加し、前記基材に硬質炭素膜を形成するステップを有することを特徴とする硬質炭素膜形成方法としたものであり、下地層を形成するステップ、混合層を形成するステップ、硬質炭素膜を形成するステップを有することで硬質炭素膜被覆部材の密着力が向上する作用を有する。
【００１３】
本発明の請求項６記載の発明は、請求項５記載の硬質炭素膜形成方法であって、前記蒸発源はＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族から選ばれた金属であることを特徴とする硬質炭素膜形成方法としたものであり、蒸発源をＩＶａ、Ｖａ、ＶＩａ、ＶＩＩａ、ＶＩＩＩａ、ＩＶｂ族の金属元素から選ぶことによって下地と基材の密着力が向上する作用を有する。
【００１４】
本発明の請求項７記載の発明は、請求項５および６に記載の硬質炭素膜形成方法であって、前記混合層は下地側から硬質炭素層側に向かって、金属と炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１５】
本発明の請求項８記載の発明は、請求項５〜７に記載の硬質炭素膜被覆部材形成方法であって、前記混合層を形成するステップは、前記混合ガス中の炭化水素ガスの比率を連続的または段階的に変化させることにより、金属と炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１６】
本発明の請求項９記載の発明は、請求項５〜７に記載の硬質炭素膜形成方法であって、前記混合層を形成するステップは、前記蒸発源の蒸発量を連続的または段階的に変化させることにより、金属と炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１７】
本発明の請求項１０記載の発明は、請求項５〜７に記載の硬質炭素膜形成方法であって、前記混合層を形成するステップは、更に前記基材支持台に高周波電圧を供給し、前記高周波電圧を連続的または段階的に変化させることにより、金属と炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１８】
本発明の請求項１１記載の発明は、請求項５〜７に記載の硬質炭素膜形成方法であって、前記混合層を形成するステップは、前記ガス供給手段により少なくとも不活性ガスと炭化水素ガスの混合ガスを供給し、前記基材支持台に高周波電圧を供給し、前記混合ガス中の炭化水素ガスの比率、前記高周波電圧の振幅、前記蒸発源の蒸発量のうちいずれか１つ以上を一定とし、残りを連続的または段階的に変化させることにより、金属と炭素の濃度が連続的または段階的に変化していることを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００１９】
本発明の請求項１２記載の発明は、請求項８〜１０に記載の硬質炭素膜形成法であって、前記混合層を形成するステップは、請求項８〜１０のいずれか１つ以上を用いて形成することを特徴とする硬質炭素膜形成方法としたものであり、混合層が下地層側から硬質炭素膜層側に向かって金属と炭素の濃度が連続的または段階的に変化させることによって下地と混合層、混合層と硬質炭素膜層の密着力が向上する作用を有する。
【００２０】
本発明の請求項１３記載の発明は、請求項５〜１３のいずれかに記載の硬質炭素膜形成方法であって、前記蒸発源は不活性ガスイオンを前記蒸発源表面に加速衝突させ、前記蒸発源の材料を蒸発させることを特徴とする。硬質炭素膜形成方法としたものであり、硬質炭素膜被覆部材の密着力が向上する作用を有する。
以下、本発明の好適な実施の形態について説明する。
【００２１】
（実施の形態１）
以下本発明における好適な実施の形態を説明する。図１は本発明における第１の実施の形態を示す硬質炭素膜が形成された部材の断面図である。１は金型、工具、機械部品などの部材であり、２は例えば、超硬合金、ステンレス、アルミなどの基材、３は金属元素から成る下地層、４は金属と炭素が混在している混合層、５は硬質炭素膜層である。この実施の形態では下地層として、基材２との密着性に優れるシリコン、チタン、タングステン、クロムからなる郡から選ばれた金属の薄膜を用い、混合層は下地層材料の炭化物で構成する場合について示す。
【００２２】
図２はこの実施の形態で用いるのに適した装置の断面図である。この図において６は内部を真空状態に保持可能な真空容器、７は真空容器を真空にする排気手段、８は原料ガスを供給するガス供給手段、９は真空容器内にて基材を保持する基材支持台、１０はインピーダンス調整を行う整合器、１１は高周波電源、１２はターゲットを保持するターゲットホルダ、１３は下地・混合層の原料となるターゲット、１４は直流電源となっている。
次に動作について説明する。まず基材支持台９に基材２を設置し、排気手段７にて真空容器６の内部を１×１０Ｅ−５Ｐａ程度の真空に排気したあと、基材２の表面洗浄のためにガス供給手段８より不活性ガスを供給し、真空容器６を１〜１００Ｐａ程度に調整する。
【００２３】
そして、高周波電源１１と整合器１０を作動させ、不活性ガスをプラズマ化し、イオンを発生させ同時に高周波電圧によって発生する−２００〜−１２００Ｖのセルフバイアス電圧にて基材２の表面をイオンクリーニングして基材洗浄処理を行う。
【００２４】
ここで、イオンクリーニングガスとしてはアルゴン、キセノン、ヘリウムなどの不活性ガスまたは水素ガス、不活性ガスと水素ガスの混合ガス（例えば、水素５０％＋アルゴン５０％）を用い、クリーニング処理を実施してもよい。水素イオンによる酸化物の還元反応、不活性ガスイオンのスパッタリングによる基材表面の不純物の除去が同時にできるため基材２と下地層３の密着力を向上させることができる。以上の処理によって基材表面を清浄にすることができ有機物や酸化層に起因する剥離を防止することができ、基材と下地層の密着力が向上する。
【００２５】
次に、高周波電源１１、整合器１０を停止し、ガス供給手段８による不活性ガスの供給を行ったままで真空容器６内部の圧力を０．１〜１０Ｐａに調整し、直流電源１４を駆動させ不活性ガスをプラズマ化してイオンを発生し、そのイオンにてシリコン、チタン、クロムまたはタングステンの金属で構成するターゲット１３をスパッタリングする。スパッタリングにて蒸発した粒子は基材２上に堆積して下地層を形成する。
【００２６】
次に、ガス供給手段８を用いて不活性ガス中に炭化水素ガスを混入し混合ガスを供給する。直流電源１４より供給される電力によって混合ガスをプラズマ化し、不活性ガス及び炭化水素ガスのイオンを発生させる。ターゲット１３では、炭化水素イオンが堆積すると共に、不活性ガスイオンによって堆積した炭素とターゲット１３を共にスパッタ粒子として基材２に向かって飛散し下地層３の上に蒸発源金属との炭化物として形成され基材２上に混合層４が形成される。
【００２７】
次に、直流電源１４を停止し、不活性ガスの供給も停止して炭化水素ガスを供給する。真空容器６内の圧力を５〜５０Ｐａの間で調整し、整合器１０と高周波電源１４を駆動し、炭化水素ガスのプラズマを励起し、イオンを発生させる。高周波電圧１１により発生するセルフバイアス電圧は−２００〜−１２００Ｖであり、イオン化された炭化水素が基材２上に堆積し硬質炭素膜４が形成される。
【００２８】
（実施の形態２）
この実施の形態では図１の部材１における混合層４を下地層３側から硬質炭素膜層４側に向かって炭素量が徐々に増加する構成とした場合を示す。図３は硬質炭素膜が形成された金型、工具、機械部品などの部材の断面図を示している。下地層３としてのチタン膜側から硬質炭素膜が形成されている方向に向かって炭素量が増加し、チタン量が減少している構成となっている。
【００２９】
次に動作について説明する。実施の形態１の場合と同様に図２において、基材支持台に９に基材２を設置した後、真空容器６を排気手段７によって１×１０Ｅ−５Ｐａ程度まで真空引きを行う。真空引きが完了すると実施の形態１と同様にガス供給手段８により、クリーニングガスを供給し、基材表面のクリーニングを行い酸化物、付着物などの除去して基材２表面と下地層３と混合層４と硬質炭素膜層５の密着力を向上させる。次にガス供給手段８から不活性ガスを供給し直流電源１４にて不活性ガスをプラズマ化しイオンを発生させる。そのイオンにより、ターゲット１３を蒸発させ基材２上にチタンを堆積させ下地層３を形成する。
【００３０】
続いて直流電源１４は駆動させたままで、ガス供給手段８より炭化水素のガスの供給を開始する。供給される炭化水素ガスは、不活性ガスと同様にプラズマ化されイオンが発生するのでターゲット１３上にて反応性スパッタとなり、基材２上に炭化チタンが形成される。このとき炭化水素の供給量を連続的に増加させると、混合層４では初期の段階においてチタンが炭素に比べて多く含有され、混合ガス中の炭化水素比率の増加に従い混合層４中の炭素量が増加し最終的には基材上でチタンよりも炭素の含有量が多くなり結果として図３に示されるように混合層中で炭素量が連続的に変化する傾斜層が形成される。
【００３１】
ここで、炭化水素ガスの供給量を図４に示されるように段階的に変化させ、混合層４中の炭素量が段階的に変化するように混合層４を形成してもかまわない。ついで実施の形態１と同様に直流電源１４の供給を停止し、不活性ガスの供給を停止して炭化水素ガスのみを供給する。真空容器内の圧力を５〜５０Ｐａの間で調整し、整合器１０と高周波電源１４を駆動し、炭化水素ガスのプラズマを励起し、イオンを発生させる。高周波電圧１１により発生するセルフバイアス電圧は−２００〜−１２００Ｖであり、イオン化された炭化水素が基材２上に堆積し硬質炭素膜４が形成される。
【００３２】
以上同一真空容器６内部にて金属のターゲット１４を備え、ターゲットの蒸発により基材２上に金属下地層３を形成し、その後大気開放なしに、同一真空容器内で炭素量が連続的または段階的に変化する混合層４を下地層３の上に形成し、炭化水素雰囲気中で基材に高周波電源１１を印加することで混合層４上に硬質炭素膜５を形成できる。図３、４に示した例によると混合層４中で炭素量が連続的に変化させることができ密着力を向上させることができるので、耐磨耗性、耐食性に優れた金型、工具、機械部品などの部材１が得られる。
【００３３】
（実施の形態３）
実施の形態２と類似しているが、この実施の形態では混合層４の形成を混合ガス中の炭化水素ガスと不活性ガスの混合比を一定にした混合ガスをガス供給手段８より供給する。ついで直流電源１４にて供給する電力を図５に示すように連続的に変化させることで、炭素構成量が連続的に変化する混合層を形成するものである。直流電源１４からの供給電力が増えると、ターゲット表面に堆積する炭素量が増加する。従ってターゲット表面に炭化チタンまたは炭素として形成される量が増えるので蒸発粒子中の炭素濃度が増え基材２上にてチタンと炭素の比率は直流電力の上昇に伴って変動する。
【００３４】
ここで、直流電力の増加量を図６に示されるように段階的に変化させ、炭素量が段階的に変化するように混合層４を形成してもかまわない。
【００３５】
（実施の形態４）
実施の形態２と類似しているが、この実施の形態では混合層形成を炭化水素ガスと不活性ガスの混合比を一定にした混合ガスをガス供給手段８より供給し、更に直流電源１４から一定電力を供給し、更に基材２に高周波電源１１から高周波電力を印加する。供給された混合ガスは直流電源１４によってプラズマ化されて不活性ガスイオンと、炭化水素イオンを生成する。ガスイオンはターゲット１３表面に衝突し、チタン、炭素のスパッタ粒子が発生する。その粒子が基材２上に堆積してチタン、炭素の混合層が形成される。ここで、高周波電力を供給すると、イオンが基材２表面に向かって加速され、基材上に炭素が堆積する。従って、図７に示すように供給する高周波電力量を連続的に増加させることで、基材２上に堆積する炭素量を連続的に増加させることができ、傾斜構造を有する混合層４を形成できる。
【００３６】
ここで、高周波電力の増加量を図８に示されるように段階的に変化させ、炭素量が段階的に変化するように混合層を形成してもかまわない。
【００３７】
（実施の形態５）
下地層の形成までは実施の形態１〜４と同じであるので、混合層の形成より説明する。混合層の形成時にガス供給手段８より不活性ガスと炭化水素ガスの混合ガスを供給し、ターゲット１３と基材２にそれぞれ直流電源１４と高周波電源１１を供給し混合ガスをプラズマ化しイオンを生成する。ここで図９にて示されるように、直流電源１４の電力量と高周波電源１１の電力量は混合層形成時中は一定にしておく。混合ガスの混合比を連続的に変化させることにより、真空容器６の雰囲気中の炭化水素量が変化し、ターゲット１３表面では反応する炭化水素の量が変化し蒸発粒子中の炭素量が変化する。また基材２側でも堆積する炭素量が同じく変化する。従って混合層形成時に混合ガス中の炭化水素濃度を増加させることで混合層４中の炭素量が連続的に変化する傾斜構造をもった混合層を形成することができる。
【００３８】
ここで、図１０に示されるように混合ガスの混合比を一定にしておき、直流電力と高周波電力を連続的に変化させることで混合層を形成してもかまわない。また混合ガスの混合比と直流電力と高周波電力のうちいずれか１つまたは２つを一定にしておき、残りの２つまたは１つを変化させて混合層を形成するようにしてもかまわない。更に、混合ガスの混合比と直流電力と高周波電力のすべてを連続的に変化させることによっても炭素量が連続的に変化する混合層を形成可能なことはいうまでもない。
またそれぞれを段階的に変化させることにより炭素量が段階的に変化する混合層が形成できることはいうまでもない。
【００３９】
（実施の形態６）
図１１は本発明にかかる硬質炭素膜を誘導結合方式を用いて構成した装置の断面図である。装置は内部を真空に保つことができる真空容器６、排気手段７、原料ガス供給手段８、基材支持台９、整合器１０、バイアス用高周波電源１１、ターゲット１３、バイアス用直流電源１４、誘導コイル１５、プラズマ励起用高周波電源１６にて構成される成膜装置である。この実施例では誘導コイル外装型について記載するが、内装型の誘導コイルを有する誘導結合型成膜装置であってもなんら問題ではない。
【００４０】
ターゲット１３としては基材２との密着性に優れるシリコン、チタン、タングステン、クロムからなる郡から選ばれる金属で構成される。次に動作について説明する。まず基材支持台に基材２を設置し、排気手段７にて真空容器６の内部を１×１０Ｅ−４Ｐａ程度の真空に排気したあと、基材２の表面洗浄のためにガス供給手段６より不活性ガスを供給し、真空容器６を０．１〜１００Ｐａ程度に圧力を調整する。
【００４１】
そして、高周波電源と整合器１７を作動させ誘導コイル１５に高周波電力を供給し、不活性ガスをプラズマ化し、イオンを発生させる。同時に高周波電源１１と整合器１０を作動させ基材２にバイアス高周波電圧を印加する。高周波電圧によって加速されたアルゴンイオンは、基材２の表面に衝突し酸化膜やその他の表面上の不純物が除去される。
【００４２】
ここで、イオンクリーニングガスとしてはアルゴン、キセノン、ヘリウムなどの不活性ガスまたは水素ガス、不活性ガスと水素ガスの混合ガス（例えば、水素５０％＋アルゴン５０％）を用いクリーニング処理を実施してもよい。水素イオンによる酸化物の還元反応、不活性ガスイオンによるスパッタリングによる基材表面の不純物の除去ができるため基材２と下地層３の密着力を向上させることができる。以上の処理によって基材表面を清浄にすることができ、有機物や酸化層に起因する剥離を防止することができ、基材と下地層の密着力が向上する。
【００４３】
次に、基材２に印加されている高周波電源１１と誘導コイル１５に印加される高周波電力の供給を停止する。不活性ガスの供給を行ったままで、真空容器６内部の圧力を０．１〜１０Ｐａ程度に調整し、再度誘導コイル１５に高周波電力を供給して、不活性ガスをプラズマ化しイオンを生成する。イオン化されたアルゴンは、ターゲット１３に印加するバイアス直流電源１４によってターゲット１３に向かって加速される。加速されたイオンはターゲット１３表面に衝突することでスパッタ粒子を生成し、粒子が飛散して基材２上にターゲット１３の材料と同じ材料の下地層３が形成される。
【００４４】
次に、ガス供給手段８を用いて不活性ガス中に炭化水素ガスを混合し混合ガスを真空容器６内部に供給する。高周波電源１６によって混合ガスをプラズマ化し、不活性ガスイオンおよび炭化水素イオンを生成する。バイアス直流電源１４及びバイアス高周波電源１１により、イオンはそれぞれターゲット１３と基材２に向かって加速される。ターゲット１３側では炭化水素イオンが堆積すると共に、不活性ガスイオンによって堆積した炭素とチタンを共にスパッタ粒子として飛散させ基材２側に炭化物として堆積させる。基材２側では同じく炭化水素イオンが堆積しスパッタ粒子と共に炭化物を形成する。これらによって下地層の上に混合層４として炭化物が形成される。
【００４５】
ここで、混合層４では完全な炭化物層以外に炭素量が下地層から表面層に向かって連続的に変化する傾斜的な組成を示すものであってもよく、また炭素量が下地層から表面層に向かって段階的に変化する構造であっても構わない。このときの制御因子はバイアス直流電圧の大きさ、バイアス高周波電圧の大きさ、混合ガス中炭化水素の比率の３つでありこれら因子の１以上を組み合わせて混合層を形成するものであれば、本発明の請求の範囲を逸脱するものではない。
【００４６】
次に、バイアス直流電圧１４を停止し、不活性ガスの供給も停止して炭化水素ガスのみを供給する。真空容器６内の圧力を５〜５０Ｐａの間で調整し、整合器１６と高周波電源１７を駆動し炭化水素ガスのプラズマを励起し、炭化水素イオンを発生させる。更にバイアス高周波電圧１１を印加してイオン化された炭化水素の分子が基材２上に堆積し混合層４上に硬質炭素膜５が形成される。
【００４７】
また、本実施の形態において誘導結合方式と同様に、例えば熱電子を利用したプラズマ装置、電子ビームによる蒸着装置、アークイオンプレーティング装置、イオンミキシング装置などにおいても下地材料の成膜量と炭素の成膜量を制御することによって同様の効果を得ることが可能である。
【００４８】
実施の形態１〜６において用いられる炭化水素ガスは、メタン、アセチレン、プロパン、ベンゼン、クメン、シクロヘキサン、トルエン、キシレンなど炭化水素系のガスであれば本発明の範囲を逸脱することはない。また硬質炭素膜形成時にこれらのガスと同時に準安定な水素、アルゴン、ヘリウムなどのガスを混合するとプラズマが励起しやすくなりさらによい。
【００４９】
実施の形態１〜６においてまた下地層３、混合層４の材料はチタン以外にシリコン、クロム、タングステンを用いた場合でも同様の効果を得ることができるのは言うまでもない。また、これらの金属を複数層重ねた多層構造であっても同様の効果を得ることができる。
【００５０】
【発明の効果】
以上のように本発明の硬質炭素膜成膜方法によれば、下地層、混合層、硬質炭素膜層を１つの真空容器の内部で形成することができ、混合ガスのガス比、蒸発源の蒸発量、基材の炭素の堆積量の少なくともいずれか１つを制御することで炭素量が変化する混合層を作成することが可能である。従って密着性のよい硬質炭素膜を安価に、容易に提供できる。
【図面の簡単な説明】
【図１】本発明の実施の形態１における硬質炭素膜が被覆された部材の断面図
【図２】本発明の実施の形態１における硬質炭素膜形成装置の断面図
【図３】本発明の実施の形態２における硬質炭素膜が被覆された部材の断面図
【図４】本発明の実施の形態２における硬質炭素膜が被覆された部材の断面図
【図５】本発明の実施の形態３における硬質炭素膜が被覆された部材の断面図
【図６】本発明の実施の形態３における硬質炭素膜が被覆された部材の断面図
【図７】本発明の実施の形態４における硬質炭素膜が被覆された部材の断面図
【図８】本発明の実施の形態４における硬質炭素膜が被覆された部材の断面図
【図９】本発明の実施の形態５における硬質炭素膜が被覆された部材の断面図
【図１０】本発明の実施の形態５における硬質炭素膜が被覆された部材の断面図
【図１１】本発明の実施の形態６における硬質炭素膜形成装置の断面図
【符号の説明】
１　硬質炭素膜被覆部材
２　基材
３　下地層
４　混合層
５　硬質炭素膜層
６　真空容器
７　排気手段
８　ガス供給手段
９　基材支持台
１０　整合器
１１　高周波電源
１２　ターゲットホルダ、
１３　ターゲット
１４　直流電源
１５　誘導コイル
１６　高周波電源
１７　整合器[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a method for forming a hard carbon film-coated member having excellent adhesion to a substrate.
[0002]
[Prior art]
The hard carbon film (DLC) has a high hardness, a good wear resistance, a high self-lubricating property, and a very small surface roughness due to its amorphous structure, so that the coefficient of friction is very small. Furthermore, it is physically stable and has high chemical durability. For this reason, it has been used for cutting and processing tools, dies, and mechanical parts since ancient times, and in recent years it has been partially used as a protective film for the recording surface of magnetic disk recording devices, the surface of magnetic recording heads, and the sliding parts of spindle motor bearings. Have been.
[0003]
On the other hand, when a hard carbon film is formed on a substrate such as super steel, stainless steel, or resin, an extremely large internal stress is generated during the film formation, and since the deformability is extremely small, the adhesion to the substrate is weak and the film is peeled off. It has the disadvantage of being easy to do. As a technique for improving the adhesion of such a hard carbon film to a substrate, there has been proposed a method of providing an intermediate layer formed of a dissimilar metal as an adhesion layer between the substrate and the substrate.
[0004]
For example, in JP-A-2000-119843 and JP-A-2002-36991, a member having a two-layered intermediate layer formed thereon is described. In JP-A-10-203896, a metal element is used as a base layer, and metal and carbon are used as a second layer. There has been proposed a method for improving the adhesion by using an intermediate layer having a structure in which the angle of change changes in an inclined manner.
[0005]
[Problems to be solved by the invention]
However, the technologies proposed so far only show the configuration of a multilayer intermediate layer or a member in which carbon is inclinedly changed, and show a method of manufacturing a hard carbon film suitable for mass production. It's not. The present invention has been made in view of the above problems, and provides a hard carbon film having high productivity and high adhesion.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a hard carbon film-coated member of the present invention has a substrate in which a hard carbon film is formed via an intermediate layer composed of an underlayer and a mixed layer, and the underlayer is composed of IVa, Va, VIa. , VIIa, VIIIa, IVb metal elements, and the mixed layer is a carbide of a group IVa, Va, VIa, VIIa, VIIIa, IVb metal element or a group IVa, Va, VIa, VIIa, VIIIa, IVb metal element and carbon. Is characterized in that the concentration changes stepwise or continuously from the base layer side to the hard carbon film layer side.
[0007]
ADVANTAGE OF THE INVENTION According to this invention, the member coat | covered with the hard carbon film with high adhesion easily can be provided irrespective of the material of a base material.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The invention according to claim 1 of the present invention is a member in which a hard carbon film is formed on a base material via an intermediate layer, wherein the intermediate layer includes a base layer made of a metal element and a mixed layer made of a metal compound. A hard carbon film is a hard carbon film-coated member characterized by having a hard carbon film formed through an intermediate layer composed of an underlayer made of metal and a mixed layer made of a metal compound. It has the effect of improving the adhesion of the carbon film-coated member.
[0009]
The invention according to claim 2 of the present invention is the hard carbon film-coated member according to claim 1, wherein the underlayer is a metal selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb. A hard carbon film-coated member characterized by being formed using at least one element, wherein the underlayer and the base are selected by selecting an underlayer from a metal element belonging to Group IVa, Va, VIa, VIIa, VIIIa, or IVb. It has the effect of improving the adhesion of the material.
[0010]
The invention according to claim 3 of the present invention is the hard carbon film-coated member according to any one of claims 1 and 2, wherein the mixed layer is selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb. A hard carbon film-coated member characterized by being composed of a carbide of a metal element, wherein the mixed layer is made of a carbide of a Group IVa, Va, VIa, VIIa, VIIIa, or IVb metal, so that the base layer and the mixed layer are formed. Has the effect of improving the adhesion between the mixed layer and the hard carbon film layer.
[0011]
The invention according to claim 4 of the present invention is the hard carbon film-coated member according to any one of claims 1 to 3, wherein the mixed layer includes a metal from the base layer side toward the hard carbon layer side, A hard carbon film-coated member characterized in that the concentration of carbon changes continuously or stepwise, and the mixed layer has a metal and carbon concentration from the underlayer side toward the hard carbon film layer side. Has the effect of improving the adhesion between the underlayer and the mixed layer, and between the mixed layer and the hard carbon film layer, by changing continuously or stepwise.
[0012]
The invention according to claim 5 of the present invention is a vacuum vessel capable of maintaining a vacuum inside, a gas supply means for supplying a raw material gas to the vacuum vessel, and a substrate provided in the reaction vessel to hold a substrate. A method for forming a hard carbon film having a substrate support, a substrate provided on the substrate support, and an evaporation source, wherein an inert gas is supplied from the gas supply means, and the evaporation source is evaporated. Forming an underlayer on a material, supplying at least a mixed gas of a hydrocarbon gas and an inert gas from the gas supply unit, evaporating the evaporation source in the mixed gas, and evaporating the evaporation source on the base material. Forming a mixed layer made of a carbide of a source, and supplying at least a hydrocarbon gas from the gas supply means, further applying a high-frequency voltage to the sample stage, and forming a hard carbon film on the base material. Characterized by The method has a step of forming an underlayer, a step of forming a mixed layer, and a step of forming a hard carbon film, thereby improving the adhesion of the hard carbon film-coated member. Have.
[0013]
The invention according to claim 6 of the present invention is the method for forming a hard carbon film according to claim 5, wherein the evaporation source is a metal selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb. This is a method for forming a hard carbon film characterized by the fact that the adhesion between the base and the base material is improved by selecting the evaporation source from the metal elements belonging to the group IVa, Va, VIa, VIIa, VIIIa and IVb.
[0014]
The invention according to claim 7 of the present invention is the method for forming a hard carbon film according to claims 5 and 6, wherein the mixed layer has a continuous concentration of metal and carbon from the base side to the hard carbon layer side. A method of forming a hard carbon film characterized in that the concentration of metal and carbon is continuous or stepwise from the underlayer side to the hard carbon film layer side. This has the effect of improving the adhesion between the underlayer and the mixed layer and between the mixed layer and the hard carbon film layer.
[0015]
The invention according to claim 8 of the present invention is the method for forming a hard carbon film-coated member according to any one of claims 5 to 7, wherein the step of forming the mixed layer comprises adjusting a ratio of a hydrocarbon gas in the mixed gas. A method of forming a hard carbon film characterized in that the concentration of metal and carbon is changed continuously or stepwise by changing continuously or stepwise, and the mixed layer is formed from the underlayer side. By changing the concentration of metal and carbon continuously or stepwise toward the hard carbon film layer side, it has an effect of improving the adhesion between the base and the mixed layer, and between the mixed layer and the hard carbon film layer.
[0016]
The invention according to claim 9 of the present invention is the method for forming a hard carbon film according to any one of claims 5 to 7, wherein the step of forming the mixed layer comprises continuously or stepwise controlling the amount of evaporation of the evaporation source. By changing the concentration, the concentration of the metal and the carbon is changed continuously or stepwise, and the method for forming a hard carbon film is characterized in that the mixed layer is formed from the underlayer side to the hard carbon film layer side. By changing the concentration of metal and carbon continuously or stepwise, the effect of improving the adhesion between the base and the mixed layer, and between the mixed layer and the hard carbon film layer is obtained.
[0017]
The invention according to claim 10 of the present invention is the method for forming a hard carbon film according to claims 5 to 7, wherein the step of forming the mixed layer further comprises supplying a high-frequency voltage to the base support, By changing the high-frequency voltage continuously or stepwise, the method of forming a hard carbon film characterized in that the concentration of metal and carbon is changed continuously or stepwise, wherein the mixed layer is By changing the concentration of metal and carbon continuously or stepwise from the underlayer toward the hard carbon film layer, the adhesion between the underlayer and the mixed layer and between the mixed layer and the hard carbon film layer is improved.
[0018]
The invention according to claim 11 of the present invention is the method for forming a hard carbon film according to any one of claims 5 to 7, wherein the step of forming the mixed layer comprises at least an inert gas and a hydrocarbon gas by the gas supply means. The mixed gas is supplied, and a high-frequency voltage is supplied to the base support, and the ratio of the hydrocarbon gas in the mixed gas, the amplitude of the high-frequency voltage, and the evaporation amount of the evaporation source are set to one or more. A method of forming a hard carbon film, characterized in that the concentration of metal and carbon is changed continuously or stepwise by making the remaining constant or stepwise changing the remaining. Has the effect of improving the adhesion between the underlayer and the mixed layer, and between the mixed layer and the hard carbon film layer by continuously or stepwise changing the concentration of metal and carbon from the underlayer side to the hard carbon film layer side. .
[0019]
The invention according to claim 12 of the present invention is the method for forming a hard carbon film according to claims 8 to 10, wherein the step of forming the mixed layer uses any one or more of claims 8 to 10. A method of forming a hard carbon film, characterized in that the mixed layer continuously or stepwise changes the concentration of metal and carbon from the underlayer side toward the hard carbon film layer side. It has the effect of improving the adhesion between the base and the mixed layer, and between the mixed layer and the hard carbon film layer.
[0020]
The invention according to claim 13 of the present invention is the method for forming a hard carbon film according to any one of claims 5 to 13, wherein the evaporation source causes accelerated collision of inert gas ions with the surface of the evaporation source, It is characterized in that the material of the evaporation source is evaporated. This is a method for forming a hard carbon film, and has an effect of improving the adhesion of the hard carbon film-coated member.
Hereinafter, preferred embodiments of the present invention will be described.
[0021]
(Embodiment 1)
Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 is a cross-sectional view of a member on which a hard carbon film is formed according to a first embodiment of the present invention. 1 is a member such as a mold, a tool, a mechanical part, etc., 2 is a base material such as cemented carbide, stainless steel, aluminum, etc., 3 is an underlayer made of a metal element, and 4 is a mixture of metal and carbon. The mixed layer 5 is a hard carbon film layer. In this embodiment, a thin film of a metal selected from the group consisting of silicon, titanium, tungsten, and chromium having excellent adhesion to the substrate 2 is used as the underlayer, and the mixed layer is made of a carbide of the underlayer material. It shows about.
[0022]
FIG. 2 is a sectional view of an apparatus suitable for use in this embodiment. In this figure, reference numeral 6 denotes a vacuum container capable of holding the inside in a vacuum state, 7 denotes exhaust means for evacuating the vacuum container, 8 denotes gas supply means for supplying a raw material gas, and 9 denotes a substrate held in the vacuum container. A substrate support 10, a matching device for adjusting the impedance, a high-frequency power supply 11, a target holder 12 for holding a target, a target 13 as a raw material for a base / mixed layer, and a direct-current power supply 14.
Next, the operation will be described. First, the substrate 2 is placed on the substrate support 9, and the inside of the vacuum vessel 6 is evacuated to a vacuum of about 1 × 10E-5 Pa by the exhaust unit 7, and then the gas supply unit is used for cleaning the surface of the substrate 2. An inert gas is supplied from 8 to adjust the vacuum container 6 to about 1 to 100 Pa.
[0023]
Then, the high-frequency power supply 11 and the matching device 10 are operated to turn the inert gas into plasma, generate ions, and simultaneously perform ion cleaning on the surface of the base material 2 with a self-bias voltage of -200 to -1200 V generated by the high-frequency voltage. To perform a substrate cleaning process.
[0024]
Here, as an ion cleaning gas, a cleaning process is performed using an inert gas such as argon, xenon, helium, or a hydrogen gas, or a mixed gas of an inert gas and a hydrogen gas (eg, 50% hydrogen + 50% argon). May be. Since the reduction reaction of the oxide by hydrogen ions and the removal of impurities on the substrate surface by sputtering of inert gas ions can be performed at the same time, the adhesion between the substrate 2 and the underlayer 3 can be improved. By the above treatment, the surface of the base material can be cleaned, the peeling due to the organic substance and the oxide layer can be prevented, and the adhesion between the base material and the base layer is improved.
[0025]
Next, the high-frequency power supply 11 and the matching device 10 are stopped, the pressure inside the vacuum vessel 6 is adjusted to 0.1 to 10 Pa while the inert gas is supplied by the gas supply means 8, and the DC power supply 14 is driven. The inert gas is turned into plasma to generate ions, and the ions are used to sputter a target 13 made of silicon, titanium, chromium, or tungsten. Particles evaporated by sputtering are deposited on the substrate 2 to form an underlayer.
[0026]
Next, hydrocarbon gas is mixed into the inert gas using the gas supply means 8 to supply a mixed gas. The mixed gas is turned into plasma by electric power supplied from the DC power supply 14 to generate ions of an inert gas and a hydrocarbon gas. At the target 13, hydrocarbon ions are deposited, and the carbon deposited by the inert gas ions and the target 13 are both scattered as sputter particles toward the base material 2 and formed on the underlayer 3 as carbides with the evaporation source metal. Thus, the mixed layer 4 is formed on the substrate 2.
[0027]
Next, the DC power supply 14 is stopped, the supply of the inert gas is also stopped, and the hydrocarbon gas is supplied. The pressure in the vacuum vessel 6 is adjusted between 5 and 50 Pa, and the matching device 10 and the high-frequency power supply 14 are driven to excite the hydrocarbon gas plasma and generate ions. The self-bias voltage generated by the high-frequency voltage 11 is −200 to −1200 V, and the ionized hydrocarbon is deposited on the base material 2 to form the hard carbon film 4.
[0028]
(Embodiment 2)
In this embodiment, a case is shown in which the mixed layer 4 in the member 1 of FIG. 1 has a structure in which the amount of carbon gradually increases from the underlayer 3 side to the hard carbon film layer 4 side. FIG. 3 is a cross-sectional view of a member such as a mold, a tool, and a machine component on which a hard carbon film is formed. The structure is such that the amount of carbon increases from the titanium film side as the underlayer 3 toward the direction in which the hard carbon film is formed, and the amount of titanium decreases.
[0029]
Next, the operation will be described. As in Embodiment 1, in FIG. 2, after the base material 2 is placed on the base support 9, the vacuum container 6 is evacuated to about 1 × 10E-5 Pa by the exhaust means 7. When the evacuation is completed, the cleaning gas is supplied by the gas supply means 8 to clean the surface of the base material to remove oxides and deposits, and the surface of the base material 2 and the underlayer 3 are removed as in the first embodiment. The adhesion between the mixed layer 4 and the hard carbon film layer 5 is improved. Next, an inert gas is supplied from the gas supply means 8 and the inert gas is turned into plasma by the DC power supply 14 to generate ions. The target 13 is evaporated by the ions to deposit titanium on the base material 2 to form the underlayer 3.
[0030]
Subsequently, the supply of hydrocarbon gas from the gas supply means 8 is started while the DC power supply 14 is driven. The supplied hydrocarbon gas is converted into plasma and generates ions in the same manner as the inert gas, so that reactive sputtering is performed on the target 13, and titanium carbide is formed on the base material 2. At this time, if the supply amount of hydrocarbons is continuously increased, the mixed layer 4 contains a larger amount of titanium in the initial stage than carbon, and the amount of carbon in the mixed layer 4 increases as the hydrocarbon ratio in the mixed gas increases. As a result, the content of carbon on the substrate becomes larger than that of titanium, and as a result, as shown in FIG. 3, a gradient layer in which the amount of carbon continuously changes in the mixed layer is formed.
[0031]
Here, the supply amount of the hydrocarbon gas may be changed stepwise as shown in FIG. 4, and the mixed layer 4 may be formed such that the amount of carbon in the mixed layer 4 changes stepwise. Then, as in the first embodiment, the supply of the DC power supply 14 is stopped, the supply of the inert gas is stopped, and only the hydrocarbon gas is supplied. The pressure in the vacuum vessel is adjusted to between 5 and 50 Pa, and the matching device 10 and the high-frequency power source 14 are driven to excite the hydrocarbon gas plasma and generate ions. The self-bias voltage generated by the high-frequency voltage 11 is −200 to −1200 V, and the ionized hydrocarbon is deposited on the base material 2 to form the hard carbon film 4.
[0032]
As described above, a metal target 14 is provided inside the same vacuum vessel 6, and a metal base layer 3 is formed on the base material 2 by evaporating the target. The hard carbon film 5 can be formed on the mixed layer 4 by forming the mixed layer 4 which changes gradually on the base layer 3 and applying the high frequency power supply 11 to the substrate in a hydrocarbon atmosphere. According to the examples shown in FIGS. 3 and 4, since the amount of carbon can be continuously changed in the mixed layer 4 and the adhesion can be improved, a mold and a tool having excellent wear resistance and corrosion resistance can be obtained. A member 1 such as a mechanical part is obtained.
[0033]
(Embodiment 3)
Although similar to the second embodiment, in this embodiment, the mixed layer 4 is formed by supplying a mixed gas having a constant mixing ratio between the hydrocarbon gas and the inert gas in the mixed gas from the gas supply means 8. . Next, the power supplied by the DC power supply 14 is continuously changed as shown in FIG. 5, thereby forming a mixed layer in which the carbon composition changes continuously. As the power supplied from the DC power supply 14 increases, the amount of carbon deposited on the target surface increases. Therefore, the amount of titanium carbide or carbon formed on the target surface increases, so that the carbon concentration in the evaporated particles increases, and the ratio of titanium to carbon on the substrate 2 changes with an increase in DC power.
[0034]
Here, the amount of increase in the DC power may be changed stepwise as shown in FIG. 6, and the mixed layer 4 may be formed so that the carbon amount changes stepwise.
[0035]
(Embodiment 4)
Although similar to the second embodiment, in this embodiment, a mixed layer is formed by supplying a mixed gas having a constant mixture ratio of a hydrocarbon gas and an inert gas from a gas supply unit 8, and further from a DC power supply 14. A constant power is supplied, and a high frequency power is applied to the base material 2 from a high frequency power supply 11. The supplied mixed gas is turned into plasma by the DC power supply 14 to generate inert gas ions and hydrocarbon ions. The gas ions collide with the surface of the target 13 to generate sputtered particles of titanium and carbon. The particles are deposited on the substrate 2 to form a mixed layer of titanium and carbon. Here, when high-frequency power is supplied, ions are accelerated toward the surface of the substrate 2 and carbon is deposited on the substrate. Therefore, as shown in FIG. 7, by continuously increasing the amount of high-frequency power supplied, the amount of carbon deposited on the base material 2 can be continuously increased, and the mixed layer 4 having the inclined structure is formed. it can.
[0036]
Here, the increase amount of the high frequency power may be changed stepwise as shown in FIG. 8, and the mixed layer may be formed so that the carbon amount changes stepwise.
[0037]
(Embodiment 5)
Since the steps up to the formation of the underlayer are the same as those of the first to fourth embodiments, the formation of the mixed layer will be described. During the formation of the mixed layer, a mixed gas of an inert gas and a hydrocarbon gas is supplied from the gas supply means 8, and a DC power supply 14 and a high-frequency power supply 11 are supplied to the target 13 and the substrate 2, respectively, to plasma the mixed gas to generate ions. I do. Here, as shown in FIG. 9, the electric energy of the DC power supply 14 and the electric energy of the high-frequency power supply 11 are kept constant during the formation of the mixed layer. By continuously changing the mixing ratio of the mixed gas, the amount of hydrocarbons in the atmosphere of the vacuum vessel 6 changes, the amount of hydrocarbons reacting on the surface of the target 13 changes, and the amount of carbon in the evaporated particles changes. . The amount of carbon deposited also changes on the substrate 2 side. Therefore, by increasing the hydrocarbon concentration in the mixed gas at the time of forming the mixed layer, a mixed layer having an inclined structure in which the amount of carbon in the mixed layer 4 changes continuously can be formed.
[0038]
Here, as shown in FIG. 10, the mixing ratio of the mixed gas may be kept constant, and the mixed layer may be formed by continuously changing the DC power and the high-frequency power. Alternatively, one or two of the mixing ratio of the mixed gas, the DC power, and the high-frequency power may be kept constant, and the remaining two or one may be changed to form a mixed layer. Further, it is needless to say that a mixed layer in which the amount of carbon continuously changes can be formed by continuously changing the mixing ratio of the mixed gas and all of the DC power and the high-frequency power.
Needless to say, a mixed layer in which the amount of carbon changes stepwise can be formed by changing each stepwise.
[0039]
(Embodiment 6)
FIG. 11 is a cross-sectional view of an apparatus in which a hard carbon film according to the present invention is formed by using an inductive coupling method. The apparatus has a vacuum vessel 6 capable of keeping the inside vacuum, an exhaust unit 7, a raw material gas supply unit 8, a substrate support 9, a matching unit 10, a high frequency power source 11 for bias, a target 13, a direct current power source 14 for bias, and induction. This is a film forming apparatus including a coil 15 and a high frequency power supply 16 for plasma excitation. In this embodiment, an induction coil exterior type will be described. However, there is no problem even with an induction coupling type film forming apparatus having an interior type induction coil.
[0040]
The target 13 is made of a metal selected from the group consisting of silicon, titanium, tungsten, and chromium, which has excellent adhesion to the substrate 2. Next, the operation will be described. First, the base material 2 is set on the base support, and the inside of the vacuum vessel 6 is evacuated to about 1 × 10E-4 Pa by the evacuation means 7, and then the gas supply means 6 is used for cleaning the surface of the base material 2. A more inert gas is supplied, and the pressure of the vacuum vessel 6 is adjusted to about 0.1 to 100 Pa.
[0041]
Then, the high-frequency power supply and the matching device 17 are operated to supply high-frequency power to the induction coil 15 to turn the inert gas into plasma and generate ions. At the same time, the high-frequency power supply 11 and the matching device 10 are operated to apply a bias high-frequency voltage to the substrate 2. The argon ions accelerated by the high-frequency voltage collide with the surface of the substrate 2 to remove an oxide film and other impurities on the surface.
[0042]
Here, as the ion cleaning gas, a cleaning process is performed using an inert gas such as argon, xenon, or helium, or a hydrogen gas, or a mixed gas of an inert gas and a hydrogen gas (eg, 50% hydrogen + 50% argon). Is also good. Since impurities on the substrate surface can be removed by a reduction reaction of oxides by hydrogen ions and sputtering by inert gas ions, the adhesion between the substrate 2 and the underlayer 3 can be improved. By the above treatment, the surface of the base material can be cleaned, peeling due to an organic substance or an oxide layer can be prevented, and the adhesion between the base material and the base layer can be improved.
[0043]
Next, the supply of the high frequency power 11 applied to the base material 2 and the high frequency power applied to the induction coil 15 are stopped. With the supply of the inert gas being performed, the pressure inside the vacuum vessel 6 is adjusted to about 0.1 to 10 Pa, and the high-frequency power is again supplied to the induction coil 15 to plasma the inert gas to generate ions. The ionized argon is accelerated toward the target 13 by a bias DC power supply 14 applied to the target 13. The accelerated ions collide with the surface of the target 13 to generate sputtered particles, and the particles are scattered to form an underlayer 3 of the same material as the material of the target 13 on the base material 2.
[0044]
Next, the hydrocarbon gas is mixed into the inert gas using the gas supply means 8 and the mixed gas is supplied into the vacuum vessel 6. The mixed gas is turned into plasma by the high frequency power supply 16 to generate inert gas ions and hydrocarbon ions. The ions are accelerated toward the target 13 and the substrate 2 by the bias DC power supply 14 and the bias RF power supply 11, respectively. Hydrocarbon ions are deposited on the target 13 side, and carbon and titanium deposited by the inert gas ions are both scattered as sputter particles and deposited on the substrate 2 side as carbide. On the substrate 2 side, hydrocarbon ions are similarly deposited and form carbides with sputtered particles. As a result, a carbide is formed as a mixed layer 4 on the underlayer.
[0045]
Here, the mixed layer 4 may have a graded composition in which the amount of carbon continuously changes from the underlayer to the surface layer in addition to the complete carbide layer. A structure that changes stepwise toward the layer may be used. The control factors at this time are the magnitude of the bias DC voltage, the magnitude of the bias high-frequency voltage, and the ratio of hydrocarbons in the mixed gas. If one or more of these factors are combined to form a mixed layer, It does not depart from the scope of the invention.
[0046]
Next, the bias DC voltage 14 is stopped, the supply of the inert gas is also stopped, and only the hydrocarbon gas is supplied. The pressure in the vacuum vessel 6 is adjusted to between 5 and 50 Pa, and the matching unit 16 and the high-frequency power supply 17 are driven to excite the plasma of the hydrocarbon gas to generate hydrocarbon ions. Further, hydrocarbon molecules ionized by applying the bias high-frequency voltage 11 are deposited on the substrate 2, and the hard carbon film 5 is formed on the mixed layer 4.
[0047]
Further, in the present embodiment, similarly to the inductive coupling method, for example, in a plasma device using thermoelectrons, a vapor deposition device using an electron beam, an arc ion plating device, an ion mixing device, etc. The same effect can be obtained by controlling the film formation amount.
[0048]
The hydrocarbon gas used in Embodiments 1 to 6 does not depart from the scope of the present invention as long as it is a hydrocarbon-based gas such as methane, acetylene, propane, benzene, cumene, cyclohexane, toluene, and xylene. Further, when a gas such as metastable hydrogen, argon, or helium is mixed with these gases at the time of forming the hard carbon film, the plasma is easily excited, which is more preferable.
[0049]
In Embodiments 1 to 6, it goes without saying that the same effect can be obtained even when silicon, chromium, or tungsten is used as the material of the underlayer 3 and the mixed layer 4 in addition to titanium. The same effect can be obtained even with a multilayer structure in which a plurality of these metals are stacked.
[0050]
【The invention's effect】
As described above, according to the method for forming a hard carbon film of the present invention, the underlayer, the mixed layer, and the hard carbon film layer can be formed inside one vacuum vessel, and the gas ratio of the mixed gas and the evaporation source By controlling at least one of the amount of evaporation and the amount of carbon deposited on the substrate, it is possible to create a mixed layer in which the amount of carbon changes. Therefore, a hard carbon film having good adhesion can be easily provided at low cost.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a member coated with a hard carbon film according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of the hard carbon film forming apparatus according to the first embodiment of the present invention.
FIG. 3 is a sectional view of a member coated with a hard carbon film according to a second embodiment of the present invention.
FIG. 4 is a sectional view of a member coated with a hard carbon film according to a second embodiment of the present invention.
FIG. 5 is a sectional view of a member coated with a hard carbon film according to a third embodiment of the present invention.
FIG. 6 is a sectional view of a member coated with a hard carbon film according to a third embodiment of the present invention.
FIG. 7 is a sectional view of a member coated with a hard carbon film according to a fourth embodiment of the present invention.
FIG. 8 is a sectional view of a member coated with a hard carbon film according to a fourth embodiment of the present invention.
FIG. 9 is a sectional view of a member coated with a hard carbon film according to a fifth embodiment of the present invention.
FIG. 10 is a sectional view of a member coated with a hard carbon film according to a fifth embodiment of the present invention.
FIG. 11 is a sectional view of a hard carbon film forming apparatus according to a sixth embodiment of the present invention.
[Explanation of symbols]
1 Hard carbon film coated member
2 Base material
3 Underlayer
4 Mixed layer
5 Hard carbon film layer
6. Vacuum container
7 Exhaust means
8 Gas supply means
9 Substrate support
10 Matching device
11 High frequency power supply
12 target holder,
13 Target
14 DC power supply
15 Induction coil
16 High frequency power supply
17 Matching device

Claims

A member in which a hard carbon film is formed on a base material via an intermediate layer, wherein the intermediate layer has a base layer made of a metal element and a mixed layer made of a metal compound. Membrane-coated members.

The hard carbon film-coated member according to claim 1, wherein the underlayer is formed using at least one metal element selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb. A hard carbon film-coated member.

The hard carbon film-coated member according to claim 1, wherein the mixed layer is made of a carbide of the metal element selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb. 4. Hard carbon film covering member.

The hard carbon film-coated member according to any one of claims 1 to 3, wherein the mixed layer has a metal or carbon concentration that changes continuously or stepwise from the underlayer toward the hard carbon layer. A hard carbon film-coated member characterized in that:

A vacuum container capable of maintaining the inside thereof in a vacuum, gas supply means for supplying a raw material gas to the vacuum container, a substrate supporting table installed in the reaction container and holding a substrate, and a substrate supporting table. An installed substrate and a method for forming a hard carbon film having an evaporation source, wherein an inert gas is supplied from the gas supply means, and a step of forming an underlayer on the substrate by evaporating the evaporation source, Supplying a mixed gas of a hydrocarbon gas and an inert gas from the gas supply means, evaporating the evaporation source in the mixed gas, and forming a mixed layer made of the carbide of the evaporation source on the base material; Supplying at least a hydrocarbon gas from the gas supply means, and applying a high-frequency voltage to the sample stage to form a hard carbon film on the base material.

The method for forming a hard carbon film according to claim 5, wherein the evaporation source is a metal selected from the group consisting of IVa, Va, VIa, VIIa, VIIIa, and IVb.

7. The method of forming a hard carbon film according to claim 5, wherein in the mixed layer, the concentration of metal and carbon changes continuously or stepwise from the underlayer toward the hard carbon layer. 8. A method for forming a hard carbon film.

The method for forming a hard carbon film-coated member according to claim 5, wherein the step of forming the mixed layer is performed by continuously or stepwise changing a ratio of a hydrocarbon gas in the mixed gas. A method for forming a hard carbon film, wherein the concentrations of metal and carbon are changed continuously or stepwise.

8. The method of forming a hard carbon film according to claim 5, wherein the step of forming the mixed layer includes changing the evaporation amount of the evaporation source continuously or stepwise so that the concentration of metal and carbon is reduced. 9. A method for forming a hard carbon film, wherein the method changes continuously or stepwise.

The method for forming a hard carbon film according to any one of claims 5 to 7, wherein the step of forming the mixed layer further comprises supplying a high-frequency voltage to the substrate support, and changing the high-frequency voltage continuously or stepwise. A method for forming a hard carbon film, wherein the concentrations of metal and carbon are changed continuously or stepwise.

The method for forming a hard carbon film according to claim 5, wherein the step of forming the mixed layer comprises supplying at least a mixed gas of an inert gas and a hydrocarbon gas by the gas supply unit, and supporting the base material. A high-frequency voltage is supplied to the table, and at least one of the ratio of the hydrocarbon gas in the mixed gas, the amplitude of the high-frequency voltage, and the evaporation amount of the evaporation source is kept constant, and the rest is continuously or stepwise. A method for forming a hard carbon film, wherein the concentration of metal and carbon is changed continuously or stepwise by changing the concentration.

The method of forming a hard carbon film according to any one of claims 8 to 10, wherein the step of forming the mixed layer is performed using at least one of the claims 8 to 10. Forming method.

14. The method for forming a hard carbon film according to claim 5, wherein the evaporation source accelerates and collides inert gas ions with the evaporation source surface to evaporate a material of the evaporation source. To form a hard carbon film.