JP2004319411A - Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode - Google Patents
Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode Download PDFInfo
- Publication number
- JP2004319411A JP2004319411A JP2003115171A JP2003115171A JP2004319411A JP 2004319411 A JP2004319411 A JP 2004319411A JP 2003115171 A JP2003115171 A JP 2003115171A JP 2003115171 A JP2003115171 A JP 2003115171A JP 2004319411 A JP2004319411 A JP 2004319411A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- contact electrode
- contact
- micro
- machine switch
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Abstract
Description
【０００１】
【発明の属する技術分野】
この発明は、マイクロマシンスイッチの接触電極用薄膜およびそのマイクロマシンスイッチの接触電極用薄膜を形成するためのスパッタリングターゲットに関するものである。
【０００２】
【従来の技術】
近年、軍事、民生、宇宙用のレーダーや通信システムなどでは高周波帯の需要が増大しており、これらレーダーや通信システムの一層の小型化が求められている。これら小型化を解決するためにマイクロマシン（Ｍｉｃｒｏ Ｅｌｅｃｔｒｏ−Ｍｅｃｈａｎｉｃａｌ Ｓｙｓｔｅｍ）技術の使用が注目されており、この技術を用いて作製した小型で高性能なスイッチを高周波帯回路へ組込むことにより高周波帯回路の一層の小型化が試みられている。この高周波帯回路へ組込まれるスイッチは半導体スイッチやバラクタダイオードに比べて機械的スイッチの方が損失やアイソレーション、消費電力の点で有利であるとされている（例えば、非特許文献１参照）。そのために各種のマイクロマシンスイッチが提案されており、そのマイクロマシンスイッチの接触電極にはＲｕ、Ｒｈ、Ａｕ−Ｃｏ合金からなる薄膜用いられ、これら金属の薄膜はその厚さが極めて薄いために、一般にスパッタリングにより形成されている。これらＲｕ、Ｒｈ、Ａｕ−Ｃｏ合金などの金属は粘着性が低いために接触部の粘着を最小限に抑えることができ、動作特性を一層向上させることができると言われている（例えば、特許文献１参照）。
【０００３】
【非特許文献１】
「Ｄｅｓｉｇｎ Ｗａｖｏ Ｍａｇａｚｉｎｅ」２００２ Ｎｏｖｅｍｂｅｒ 第８０〜８１頁、９９〜１００頁
【特許文献１】
特開２００１−２６６７２７号公報
【０００４】
【発明が解決しようとする課題】
確かに純Ｒｕ、純Ｒｈ、Ａｕ−Ｃｏ合金などからなる薄膜を接触電極に用いた場合、接触部の粘着を最小限に抑えることができるが、ＲｈおよびＡｕ−Ｃｏ合金は比較的高価な金属であるから、コスト削減の面で接触電極に一層安価なＲｕを使用しようとする研究が成されている。しかし、純Ｒｕからなる薄膜を接触電極に用いた場合、１０４回程度の接触／非接触による導通／非導通を繰り返すと接触抵抗が上昇するようになり、長期使用した場合、信頼性に問題がある。
【０００５】
【課題を解決するための手段】
そこで、本発明者は、かかる課題を解決すべく研究を行なった。その結果、
（イ）ＲｕにＧｅおよびＳｉのうちの１種または２種を合計で０．０１〜３質量％（以下、％は質量％を示す）含有してなるＲｕ基合金で形成した薄膜は、これをマイクロマシンスイッチの接触電極に用いると、１０６回以上接触／非接触による導通／非導通を繰り返しても接触抵抗が上昇することがなく、長期にわたって信頼性が向上する、
（ロ）このＲｕ基合金からなる薄膜は、Ｒｕ基合金粉末を燒結して得られたＲｕ基焼結合金ターゲットを用いてスパッタリングすることにより得られ、この薄膜の比抵抗は純Ｒｕ薄膜の比抵抗と大差がないほど導電性に優れている、
という研究結果が得られたのである。
【０００６】
この発明は、かかる研究結果に基づいて成されたものであって、
（１）Ｇｅ：０．０１〜３％を含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基合金からなるマイクロマシンスイッチの接触電極用薄膜、
（２）Ｓｉ：０．０１〜３％を含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基合金からなるマイクロマシンスイッチの接触電極用薄膜、
（３）ＧｅおよびＳｉを合計で０．０１〜３％含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基合金からなるマイクロマシンスイッチの接触電極用薄膜、に特徴を有するものである。
【０００７】
純Ｒｕからなるマイクロマシンスイッチの接触電極用薄膜が１０４回程度の接触／非接触による導通／非導通の繰り返しによって接触抵抗値が上昇する理由として、純Ｒｕは比抵抗が極めて小くかつ高硬度を有するが、純Ｒｕは脆いため比較的粉末になりやすい特性を有し、したがって、接触／非接触を繰り返すと接触電極用薄膜の一部が粉末化し、接触面の間に粉末が入り込んで接触電極用薄膜相互の接触面積が少なくなるが、この発明のＲｕにＧｅ、ＳｉおよびＲｅのうちの１種または２種以上を合計で０．０１〜３％（一層好ましくは、０．１〜２％）含有してなるＲｕ基合金は延性が付加されて粉末化が抑制され、接触面の間に入り込む粉末が少なくなることによるものと考えられる。
【０００８】
この発明のマイクロマシンスイッチの接触電極用薄膜の成分組成を前述のごとく限定した理由は、ＧｅおよびＳｉのうちの１種または２種を合計で３％を越えて含有すると、Ｒｕ基合金の比抵抗が大きくなって、接点材料として使用できなくなるので好ましくなく、一方、ＧｅおよびＳｉのうちの１種または２種を合計で０．０１％未満含有しても純Ｒｕの特性を変えることができず、マイクロマシンスイッチの接触電極用薄膜としての寿命を延ばすことができないことによるものである。
【０００９】
この発明のマイクロマシンスイッチの接触電極用薄膜を形成するためのスパッタリングターゲットは、この発明のマイクロマシンスイッチの接触電極用薄膜と同じ成分組成を有するＲｕ基合金粉末をホットプレスすることにより作製することができる。
【００１０】
したがって、この発明は、
（４）Ｇｅ：０．０１〜３％を含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基焼結合金からなる前記（１）記載のマイクロマシンスイッチの接触電極用薄膜形成用スパッタリングターゲット、
（５）Ｓｉ：０．０１〜３％を含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基焼結合金からなる前記（２）記載のマイクロマシンスイッチの接触電極用薄膜形成用スパッタリングターゲット、
（６）ＧｅおよびＳｉを合計で０．０１〜３％含有し、残部がＲｕおよび不可避不純物からなる組成を有するＲｕ基焼結合金からなる前記（３）記載のマイクロマシンスイッチの接触電極用薄膜形成用スパッタリングターゲット、に特徴を有するものである。
【００１１】
【発明の実施の形態】
いずれも１００メッシュアンダーの市販のＧｅ粉末、Ｓｉ粉末およびＲｕ粉末を用意し、これら粉末を所定の組成になるように配合し混合して混合粉末を作製し、得られた混合粉末を温度：１１５０℃、圧力：１５ＭＰａでホットプレスすることによりホットプレス体を作製し、これらホットプレス体をダイヤモンド砥石を使用し、回転数：２００ｒｐｍの条件で研削加工することにより直径：１２５ｍｍ、厚さ：５ｍｍの円盤状を有し、表１に示される成分組成を有する本発明ターゲット１〜１５、比較ターゲット１〜３および従来ターゲット１を作製した。
【００１２】
【表１】
これら本発明ターゲット１〜１５、比較ターゲット１〜３および従来ターゲット１をそれぞれ銅製の冷却用バッキングプレートに純度：９９．９９９重量％のインジウムろう材にてハンダ付けし、これを直流マグネトロンスパッタリング装置に装入し、ターゲットとＳｉウエハ基板の間の距離を７０ｍｍになるようにセットした後、到達真空度：５×１０−５Ｐａ以下になるまで真空引きを行い、
・基板温度：室温、
・投入電力：５０Ｗ（０．４Ｗ／ｃｍ２）、
の条件でスパッタリングを行い、Ｓｉウエハ基板の表面に厚さ：０．５μｍを有し、表２に示される成分組成の本発明接触電極用薄膜１〜１５、比較接触電極用薄膜１〜３および従来接触電極用薄膜１を形成した。これら本発明接触電極用薄膜１〜１５、比較接触電極用薄膜１〜３および従来接触電極用薄膜１の初期の抵抗値を四探針法で測定し、その結果を表２に示した。
【００１４】
さらに、幅：１００μｍ、厚さ：３００μｍでつきだし長さが４００μｍを有するＮｉ箔をアディティブ法で形成し、この表面に金メッキを０．１μｍした後、Ｓｉウエハ上に形成した薄膜と同じ成分組成を有する薄膜を０．５μｍの厚さとなるようにスパッタにより形成して針を作製した。この針にかかる最大荷重が０．２ｇになるようにプローブテスターを使用してウエハが乗っている台を１０μｍの幅で上下させ、接触抵抗が１Ωに上昇するに要した台の上下回数を表２に示した。接触抵抗が１Ωに上昇したときをマイクロスイッチのスイッチング使用不可と考えたからである。
【００１５】
【表２】
表１〜２示される結果から、本発明ターゲット１〜１５を用いてスパッタリングすることにより得られた本発明接触電極用薄膜１〜１５は、従来ターゲット１を用いてスパッタリングすることにより得られた従来接触電極用薄膜１に比べて接触抵抗が１Ωに達するまでの台の上下回数が高いことが分かる。しかし、この発明の条件から外れた成分組成を有する比較ターゲット１〜３を用いてスパッタリングすることにより得られた比較接触電極用薄膜１〜３は薄膜自体の初期の抵抗値が高すぎて接触電極として好ましくないことが分かる。
【００１７】
【発明の効果】
上述のように、この発明によると、長期間使用しても接触抵抗が上昇せず、優れた特性を有するマイクロマシンスイッチの接触電極用薄膜を低コストで提供することができ、マイクロマシン産業の発展に大いに貢献し得るものである。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thin film for a contact electrode of a micromachine switch and a sputtering target for forming the thin film for a contact electrode of the micromachine switch.
[0002]
[Prior art]
2. Description of the Related Art In recent years, demands for high-frequency bands in military, civil, and space radars and communication systems have been increasing, and there is a demand for further downsizing of these radars and communication systems. In order to solve these miniaturizations, attention has been paid to the use of a micro machine (Micro Electro-Mechanical System) technology. By incorporating a small and high-performance switch manufactured using this technology into a high frequency band circuit, Further downsizing has been attempted. It is said that mechanical switches are more advantageous in terms of loss, isolation, and power consumption than semiconductor switches and varactor diodes as switches incorporated in this high-frequency circuit (for example, see Non-Patent Document 1). For this purpose, various micromachine switches have been proposed, and a thin film made of Ru, Rh, or Au-Co alloy is used for a contact electrode of the micromachine switch. Since the thickness of these metal thin films is extremely thin, sputtering is generally performed. Is formed. It is said that these metals such as Ru, Rh, and Au-Co alloys have low adhesiveness, so that the adhesion of the contact portion can be minimized, and the operating characteristics can be further improved (for example, see Patent Reference 1).
[0003]
[Non-patent document 1]
"Design Wave Magazine", 2002 November, pages 80 to 81, 99 to 100 [Patent Document 1]
JP 2001-266727 A
[Problems to be solved by the invention]
Certainly, when a thin film made of pure Ru, pure Rh, Au-Co alloy or the like is used for the contact electrode, the adhesion of the contact portion can be minimized, but Rh and Au-Co alloy are relatively expensive metals. Therefore, research has been made to use cheaper Ru for the contact electrode in terms of cost reduction. However, when a thin film made of pure Ru to the contact electrode, become contact resistance increases with repeated conduction / non-conduction by contact / non-contact of about 10 4 times, when long-term use, a problem in reliability There is.
[0005]
[Means for Solving the Problems]
Then, the present inventor conducted research to solve such a problem. as a result,
(A) A thin film formed of a Ru-based alloy in which Ru contains one or two of Ge and Si in a total amount of 0.01 to 3% by mass (hereinafter,% indicates mass%) the use of the contact electrode of the micromachine switch, without contact resistance is increased by repeating the conduction / non-conduction by contact / non-contact at least 10 6 times, reliability is improved over time,
(B) This Ru-based alloy thin film is obtained by sputtering using a Ru-based sintered alloy target obtained by sintering a Ru-based alloy powder, and the specific resistance of this thin film is that of a pure Ru thin film. It has excellent conductivity so that there is not much difference from resistance.
The research result was obtained.
[0006]
The present invention has been made based on such research results,
(1) Ge: a thin film for a contact electrode of a micromachine switch, comprising 0.01 to 3%, and the balance being a Ru-based alloy having a composition of Ru and unavoidable impurities;
(2) a thin film for a contact electrode of a micromachine switch, comprising Si: 0.01 to 3%, and the balance being a Ru-based alloy having a composition of Ru and unavoidable impurities;
(3) A thin film for a contact electrode of a micromachine switch comprising a Ru-based alloy containing Ge and Si in a total of 0.01 to 3% and a balance of Ru and unavoidable impurities.
[0007]
The reason the thin film for the contact electrode of the micromachine switch made of pure Ru is the contact resistance by repeated connection / disconnection by the order of the contact / non-contact 10 4 times increase, net Ru is resistivity extremely small Ku and high hardness However, pure Ru is brittle and has a characteristic that it is relatively easy to become a powder. Therefore, when contact / non-contact is repeated, a part of the thin film for the contact electrode becomes powder, and the powder enters between the contact surfaces to make contact. Although the contact area between the thin films for electrodes is reduced, one or more of Ge, Si and Re are added to Ru of the present invention in a total amount of 0.01 to 3% (more preferably 0.1 to 2%). %) Is considered to be due to the fact that the contained Ru-based alloy has an added ductility, suppresses powdering, and reduces powder entering between the contact surfaces.
[0008]
The reason why the component composition of the contact electrode thin film of the micromachine switch of the present invention is limited as described above is that when one or two of Ge and Si are contained in a total of more than 3%, the specific resistance of the Ru-based alloy is increased. Is unfavorable because it becomes unusable as a contact material. On the other hand, even if the total content of one or two of Ge and Si is less than 0.01%, the characteristics of pure Ru cannot be changed. This is because the life as a thin film for a contact electrode of a micromachine switch cannot be extended.
[0009]
The sputtering target for forming the contact electrode thin film of the micromachine switch of the present invention can be produced by hot pressing a Ru-based alloy powder having the same component composition as the contact electrode thin film of the micromachine switch of the present invention. .
[0010]
Therefore, the present invention
(4) The sputtering target for forming a thin film for a contact electrode of a micromachine switch according to the above (1), comprising Ge: 0.01 to 3%, the balance being a Ru-based sintered alloy having a composition of Ru and unavoidable impurities. ,
(5) The sputtering target for forming a thin film for a contact electrode of a micromachine switch according to the above (2), wherein the sputtering target contains Si: 0.01 to 3% and the balance is a Ru-based sintered alloy having a composition of Ru and unavoidable impurities. ,
(6) The formation of a thin film for a contact electrode of a micromachine switch according to the above (3), comprising 0.01 to 3% of Ge and Si in total, and the balance being a Ru-based sintered alloy having a composition of Ru and unavoidable impurities. And a sputtering target for use.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
In each case, commercially available Ge powder, Si powder and Ru powder of 100 mesh under were prepared, and these powders were blended and mixed so as to have a predetermined composition to prepare a mixed powder, and the obtained mixed powder was heated at a temperature of 1150. A hot-pressed body was prepared by hot-pressing at 15 ° C. and a pressure of 15 MPa, and these hot-pressed bodies were ground using a diamond grindstone at a rotation speed of 200 rpm to obtain a diameter: 125 mm and a thickness: 5 mm. Inventive targets 1 to 15, comparative targets 1 to 3, and a conventional target 1 having a disk shape and having the component compositions shown in Table 1 were produced.
[0012]
[Table 1]
Each of the targets 1 to 15 of the present invention, the comparative targets 1 to 3 and the conventional target 1 was soldered to a cooling backing plate made of copper with an indium brazing material having a purity of 99.999% by weight, and this was supplied to a DC magnetron sputtering apparatus. After charging and setting the distance between the target and the Si wafer substrate to be 70 mm, vacuum evacuation was performed until the ultimate degree of vacuum: 5 × 10 −5 Pa or less,
・ Substrate temperature: room temperature
-Input power: 50 W (0.4 W / cm 2 )
Sputtering is performed under the following conditions, and the thickness of the surface of the Si wafer substrate is 0.5 μm, and the thin films for contact electrodes 1 to 15 of the present invention and the thin films for comparative contact electrodes 1 to 3 having the component compositions shown in Table 2 Conventionally, a contact electrode thin film 1 was formed. The initial resistance values of these contact electrode thin films 1 to 15 of the present invention, comparative contact electrode thin films 1 to 3 and conventional contact electrode thin film 1 were measured by a four-probe method, and the results are shown in Table 2.
[0014]
Further, a Ni foil having a width: 100 μm, a thickness: 300 μm, and a starting length of 400 μm is formed by an additive method, and after gold plating is performed on the surface by 0.1 μm, the same component composition as the thin film formed on the Si wafer is used. Was formed by sputtering to a thickness of 0.5 μm to produce a needle. Using a probe tester, the table on which the wafer is mounted is moved up and down with a width of 10 μm using a probe tester so that the maximum load applied to the needle is 0.2 g, and the number of steps required to increase the contact resistance to 1Ω is displayed. 2 is shown. This is because when the contact resistance increased to 1Ω, it was considered that the switching of the microswitch could not be used.
[0015]
[Table 2]
From the results shown in Tables 1 and 2, the thin films for contact electrodes 1 to 15 of the present invention obtained by sputtering using the targets 1 to 15 of the present invention were obtained by sputtering using the target 1 of the related art. It can be seen that the number of vertical movements of the stage until the contact resistance reaches 1Ω is higher than that of the contact electrode thin film 1. However, the comparative thin films for contact electrodes 1 to 3 obtained by sputtering using the comparative targets 1 to 3 having component compositions deviating from the conditions of the present invention have too high initial resistance values of the thin films themselves, and thus the contact electrodes It is understood that it is not preferable.
[0017]
【The invention's effect】
As described above, according to the present invention, the contact resistance does not increase even after long-term use, and a thin film for a contact electrode of a micromachine switch having excellent characteristics can be provided at low cost. It can greatly contribute.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003115171A JP2004319411A (en) | 2003-04-21 | 2003-04-21 | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003115171A JP2004319411A (en) | 2003-04-21 | 2003-04-21 | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2004319411A true JP2004319411A (en) | 2004-11-11 |
Family
ID=33474448
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003115171A Pending JP2004319411A (en) | 2003-04-21 | 2003-04-21 | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2004319411A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0215682A (en) * | 1988-04-21 | 1990-01-19 | Philips Gloeilampenfab:Nv | Device and its manufacture |
| JP2001158926A (en) * | 1999-10-25 | 2001-06-12 | Lucent Technol Inc | Product containing noble metal alloy and producing method therefor |
| JP2002069624A (en) * | 2000-08-30 | 2002-03-08 | Toshiba Corp | Sputtering target |
-
2003
- 2003-04-21 JP JP2003115171A patent/JP2004319411A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0215682A (en) * | 1988-04-21 | 1990-01-19 | Philips Gloeilampenfab:Nv | Device and its manufacture |
| JP2001158926A (en) * | 1999-10-25 | 2001-06-12 | Lucent Technol Inc | Product containing noble metal alloy and producing method therefor |
| JP2002069624A (en) * | 2000-08-30 | 2002-03-08 | Toshiba Corp | Sputtering target |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6254823B2 (en) | Nickel silicide sputtering target and manufacturing method thereof | |
| JP2016194159A (en) | Target containing molybdenum | |
| JP2013535571A5 (en) | Targets containing molybdenum | |
| TW200918679A (en) | Method for producing sintered body, sintered body, sputtering target composed of the sintered body, and sputtering target-backing plate assembly | |
| US20130175167A1 (en) | Ferromagnetic sputtering target and method for manufacturing same | |
| JPH0841634A (en) | Sputtering target for cathodic sputtering and preparation ofsaid target | |
| TWI225893B (en) | AlRu sputtering target and manufacturing method thereof | |
| JP2018162493A (en) | Tungsten silicide target and method for producing the same | |
| TW201142059A (en) | Sputtering target-backing plate assembly body | |
| WO2014157054A1 (en) | Sputtering silicide target and method for producing same | |
| JPWO2012073882A1 (en) | Sputtering target | |
| TW200422412A (en) | Silicon sintered compact and method for producing the same | |
| JP2004319410A (en) | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode | |
| JP5988140B2 (en) | Manufacturing method of MoTi target material and MoTi target material | |
| JP2004319411A (en) | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode | |
| JP2004319409A (en) | Thin film for contact electrode of micro-machine switch, and sputtering target for depositing thin film for contact electrode | |
| JP4747368B2 (en) | W-Ti target for sputtering for forming a W-Ti diffusion prevention film | |
| JP2009114531A (en) | SnO2-BASED SPUTTERING TARGET | |
| JP6007840B2 (en) | Cu-Ga sputtering target and manufacturing method thereof | |
| JP6627993B2 (en) | Cu-Ni alloy sputtering target | |
| JP7178707B2 (en) | Method for manufacturing MgO-TiO-based sputtering target | |
| JP2021521334A5 (en) | ||
| CN110964967B (en) | Back plate with low thermal expansion coefficient and manufacturing method thereof | |
| JP4110563B2 (en) | Copper alloy sputtering target | |
| JPH09118978A (en) | Target for tungsten silicide sputtering |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20060331 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20081121 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20081209 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20090401 |