JP2004018946A - HIGH-PURITY Si-Ge ALLOY TARGET AND MANUFACTURING METHOD THEREFOR, AND SPUTTERED HIGH-PURITY Si-Ge FILM - Google Patents
HIGH-PURITY Si-Ge ALLOY TARGET AND MANUFACTURING METHOD THEREFOR, AND SPUTTERED HIGH-PURITY Si-Ge FILM Download PDFInfo
- Publication number
- JP2004018946A JP2004018946A JP2002175815A JP2002175815A JP2004018946A JP 2004018946 A JP2004018946 A JP 2004018946A JP 2002175815 A JP2002175815 A JP 2002175815A JP 2002175815 A JP2002175815 A JP 2002175815A JP 2004018946 A JP2004018946 A JP 2004018946A
- Authority
- JP
- Japan
- Prior art keywords
- purity
- less
- wtppm
- alloy target
- target
- 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.)
- Granted
Links
Landscapes
- Physical Vapour Deposition (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
【0001】
【発明の属する技術分野】
この発明は、半導体特性を有し、光通信用素子や太陽電池用材料として使用することが可能である半導体素子用高純度Si−Ge系スパッタ膜又はこれらを製造するための高純度Si−Ge系合金ターゲット及びその製造方法に関する。
【0002】
【従来の技術】
従来、LSI用半導体材料としては、シリコンが最もポピュラーな材料であるが、光通信用(LE/LED)としてはインジウム・燐、ガリウム・砒素等の化合物半導体が使用されている。
しかし、インジウムは資源寿命が極めて少なく、20年程度が採掘可能年数と云われており、また砒素は周知のように毒性の強い元素である。このようなことから、現在広範囲に使用されている光通信用半導体材料は、使用上に大きな問題があると云わざるを得ない。
特に、製品寿命の短い携帯電話に使用されているガリウム・砒素の半導体素子は、強い毒性を持つ砒素があるために、これらの廃棄処理が大きな問題となっている。
【0003】
このような情況において、Si−Ge系材料が半導体特性を有することが分かり、好ましい光通信用素子や太陽電池用材料であるとの指摘がなされている。このSi−Ge系材料の大きな利点は、いずれも地球上で豊富な材料であること、また毒性等の心配が全くないことであるが、さらに従来の化合物半導体と同等の半導体特性が得られかつ安価であるという大きな利点がある。
しかし、このSi−Ge系材料に問題がないわけではなく、現在のところ高純度かつ高品質な材料に作製するための技術が確立されていないことである。
【0004】
現在、Si−Ge系材料からなる薄膜を形成する技術としては、Si−Ge系材料ターゲットをスパッタリングしてSi基板上にSi−Ge系半導体膜を形成するものである。
Si−Ge系材料からなる薄膜に含有される主な不純物としては、Fe、Ni、Co、Cu等の遷移金属元素、Na、K等のアルカリ金属元素、U、Th等の放射性元素、その他の不純物として、Al、Cr、Ca、Mg等の重金属元素又は軽金属元素が挙げられる。
前記遷移金属元素は、界面接合部のトラブルの発生原因となり、アルカリ金属元素は拡散し易く、容易に移動するためMOS−LSI界面特性の劣化につながり、また放射性元素はα線を放出し、ソフトエラーとなることが知られている。また重金属元素又は軽金属元素の存在は、電気抵抗を上げ半導体素子の動作性能の信頼性を低下させる原因となっている。
【0005】
また、酸素、炭素、窒素、水素、硫黄等のガス成分もSi−Ge系材料ターゲットのスパッタリングの際に、アーキングやパーティクル発生の原因になり、電気抵抗を上げる原因ともなっている。
しかし、Si−Ge系材料は高純度化が難しく、また一旦高純度化してもスパッタリングターゲットの製造工程では、上記のような不純物が混入し易く、純度を維持することが難しいという問題がある。したがって、Si−Ge系材料ターゲットをスパッタリングしてSi基板上にSi−Ge系半導体膜を形成する場合に、ターゲットの純度の向上は、極めて重要な問題となっている。
【0006】
また、一般にスパッタリングにより成膜する場合、成膜速度を高速化し生産効率を上げるために、成膜面積を拡大する、すなわち大きな面積のターゲットを使用してスパッタリングを行なうことが行なわれるが、スパッタリングの際の、パーティクルの発生又は膜厚の均一性が大きな問題となる。
製造工程によるSi−Ge系材料ターゲットの性状や構造がスパッタリングに直接反映されるので、従来は所定の膜組成を大きな基板に均一に成膜することが難しく、またアーキングやパーティクル発生が避けられなかった。
【0007】
【発明が解決しようとする課題】
本発明は、上記の問題を解決するために、不純物が少なく、成膜時における厚膜の均一化が可能であり、またパーティクルの発生が少なく、ユニフォーミティと膜組成が均一で、スパッタ特性が良好である、高純度Si−Ge系合金ターゲット及び該高純度ターゲットを安定して製造できる方法並びに膜厚が均一でリーク電流が少なく膜特性に優れたSi−Ge系スパッタ膜を得ることを課題とする。
【0008】
【課題を解決するための手段】
本発明は、
1.ガス成分を除き、純度が5N(99.999wt%)以上であることを特徴とする高純度Si−Ge系合金ターゲット
2.ターゲット中の不純物として、Fe、Ni、Co、Cu等の遷移金属元素がそれぞれ2wtppm以下、Na、K等のアルカリ金属元素がそれぞれ1wtppm以下、U、Th等の放射性元素の含有量が1wtppb以下、その他の不純物として、Al、Cr、Ca、Mg等の重金属元素又は軽金属元素の含有量がそれぞれ1wtppm以下であることを特徴とする上記1記載の高純度Si−Ge系合金ターゲット
3.ターゲット中のガス成分である酸素が1000wtppm以下であることを特徴とする上記1又は2記載の高純度Si−Ge系合金ターゲット
4.ターゲット中のガス成分である炭素50wtppm以下、窒素50wtppm以下、水素50wtppm以下、硫黄50wtppm以下(いずれもドーパントとする場合を除く)であることを特徴とする上記1〜3のそれぞれに記載の高純度Si−Ge系合金ターゲット
5.ターゲットの相対密度が90%以上であること特徴とする上記1〜4のそれぞれに記載の高純度Si−Ge系合金ターゲット
6.固溶組織を備えた上記1〜5のそれぞれに記載の高純度Si−Ge系合金ターゲット
7.B、C等のドーパントを固溶する範囲で含有することを特徴とする上記1〜5のそれぞれに記載の高純度Si−Ge系合金ターゲット
を提供する。
【0009】
また、本発明は、
8.主成分となる高純度Si及び高純度Geを高真空中で溶解・鋳造して合金インゴットを作製し、これを粉砕してSi−Ge系合金微粉末を作製した後、この微粉末を焼結することを特徴とする高純度Si−Ge系合金ターゲットの製造方法
9.B、C等のドーパントを固溶する範囲で含有することを特徴とする上記8記載の高純度Si−Ge系合金ターゲットの製造方法
10.Ge原料を王水等の酸に溶解してGeCl4として回収し、これを水素還元して5NレベルのGe粉末を得、この5NレベルのGe粉末と同5NレベルのSiを混合して真空中で溶解することを特徴とする上記8又は9記載の高純度Si−Ge系合金ターゲットの製造方法
11.平均粒径が1mm以上の塊状のSiと混合して溶解することを特徴とする上記10記載の高純度Si−Ge系合金ターゲットの製造方法
12.微粉末をホットプレス、熱間静水圧プレス又は放電プラズマ焼結法で焼結することを特徴とする上記8〜11のそれぞれに記載の高純度Si−Ge系合金ターゲットの製造方法
を提供する。
【0010】
また、本発明は、
13.ガス成分を除き、純度が5N(99.999wt%)以上であることを特徴とする高純度Si−Ge系スパッタ膜
14.不純物として、Fe、Ni、Co、Cu等の遷移金属元素がそれぞれ2wtppm以下、Na、K等のアルカリ金属元素がそれぞれ1wtppm以下、U、Th等の放射性元素の含有量が1wtppb以下、その他の不純物として、Al、Cr、Ca、Mg等の重金属元素又は軽金属元素の含有量がそれぞれ1wtppm以下であることを特徴とする上記13記載の高純度Si−Ge系スパッタ膜
15.ガス成分である酸素が1000wtppm以下であることを特徴とする上記13又は14記載の高純度Si−Ge系スパッタ膜
16.ガス成分である炭素50wtppm以下、窒素50wtppm以下、水素50wtppm以下、硫黄50wtppm以下(いずれもドーパントとする場合を除く)であることを特徴とする上記13〜15のそれぞれに記載の高純度Si−Ge系スパッタ膜
17.固溶組織を備えた上記13〜16のそれぞれに記載の高純度Si−Ge系スパッタ膜
18.B、C等のドーパントを固溶する範囲で含有することを特徴とする上記13〜17のそれぞれに記載の高純度Si−Ge系スパッタ膜
を提供する。
【0011】
【発明の実施の形態】
本発明のSi−Ge系合金ターゲットは、半導体特性を有する範囲の成分範囲を含む。通常5〜50wt%Si−Geであり、少量のB、C等のドーパントを固溶する範囲で含有するSi−Geターゲットを包含する。また本発明のSi−Ge系合金ターゲットは、Si−Ge固溶体の組織を備えている。
本発明のターゲットの製造に際しては、3NレベルのGe原料を王水等の酸に溶解してGeCl4として回収し、これを水素還元により5NレベルのGe粉末を得る。水素還元後、一旦これを真空中で溶解し、スラグ等の不純物を除去してさらに純度を向上させることもできる。
次に、この5NレベルのGe粉末と同5NレベルのSiを混合して真空中で溶解する。5NレベルのSiは、平均粒径1mm以下の微粉を使用すると汚染の原因となりうることから、塊状(平均粒径1mm以上)のSiを使用することが望ましい。
【0012】
上記の、主成分となる高純度Si及び高純度Geを高真空中で溶解・鋳造して合金インゴットを作製する。溶解の際、表面に浮上したスラグは除去し、純度をさらに向上させる。インゴットを粉砕してSi−Ge系合金微粉末を作製する。この微粉末は固溶体となっている。このSi−Ge系合金微粉末を焼結して高純度Si−Ge系合金ターゲットを得る。このターゲットには、B、C等のドーパントを固溶する範囲で含有することができる。
微粉末をホットプレス、熱間静水圧プレス又は放電プラズマ焼結法で焼結することができる。以上の工程により、高純度Si−Ge系合金ターゲットの製造する。
【0013】
上記の製造方法によって、本発明のターゲットは、ガス成分を除き、純度が5N(99.999wt%)以上である高純度Si−Ge系合金ターゲットを得ることができる。これによって、成膜時における厚膜の均一化が可能であり、またパーティクルの発生が少なく、ユニフォーミティと膜組成が均一で、スパッタ特性が良好である、高純度Si−Ge系合金ターゲットが得られる。
また、ターゲット中の不純物として、Fe、Ni、Co、Cu等の遷移金属元素がそれぞれ2wtppm以下、Na、K等のアルカリ金属元素がそれぞれ1wtppm以下、U、Th等の放射性元素の含有量が1wtppb以下、その他の不純物として、Al、Cr、Ca、Mg等の重金属元素又は軽金属元素の含有量がそれぞれ1wtppm以下である高純度Si−Ge系合金ターゲット得ることができ、半導体素子の動作性能の信頼性に優れた成膜が可能となる。
【0014】
ターゲット中のガス成分である酸素は1000wtppm以下、好ましくは600ppm以下、さらに好ましくは150ppm以下とすることができる。これによって、さらにパーティクルの発生を抑制し、ユニフォーミティと膜組成が均一な成膜が可能となる。
また、ターゲット中のガス成分である炭素50wtppm以下、窒素50wtppm以下、水素50wtppm以下、硫黄50wtppm以下(いずれもドーパントとする場合を除く)とすることができ、同様な特性上の向上を図ることができる。
ターゲットの相対密度は90%以上、さらには95%以上とすることができ、固溶組織を備えた高純度Si−Ge系合金ターゲットを得ることができる。
さらにターゲット組織の平均結晶粒径は300μm以下、好ましくは150μm以下、さらに好ましくは75μm以下とすることができるが、これによって、さらにアーキングやパーティクルの発生を抑制し、安定した特性を持つ膜を得ることができる。
【0015】
スパッタリングに際しては、ターゲットに安定したバイアス電圧を印加できるので、プラズマ密度が上げ易く、スパッタガス圧が低く抑えられるのでガス損傷の少ない良好な膜を得ることができる。
以上によって、パーティクルの発生が少なく、ユニフォーミティと膜組成が均一で、リーク電流が少ない膜特性に優れた成膜が可能となる。
本発明は、高純度Si−Ge系合金ターゲットを使用して形成された高純度Si−Ge系スパッタ膜の全てを包含するものである。
【0016】
【実施例及び比較例】
次に、実施例について説明する。なお、本実施例は発明の一例を示すためのものであり、本発明はこれらの実施例に制限されるものではない。すなわち、本発明の技術思想に含まれる他の態様及び変形を含むものである。
【0017】
(実施例1)
純度3NレベルのGe1500gを王水に溶解し、GeCl4として回収する。次に、これ水素還元してGe粉末1200gを得た。
これを石英ボート中で、1000°Cで真空溶解した。上部に浮いたスラグを除去した後、凝固させたものをメノウ乳鉢で粉砕し、800gのGe粉末を得た。
一方、市販品である5Nレベルの多結晶Si粉を篩いにかけ、平均粒径1mm以上の粒を200g秤量した。そして、これらの粉末を真空中で石英アンプル中に封入した。
【0018】
次に、Ge粉末及びSi粒を封入した石英アンプルを1050°Cに加熱し、溶解した。溶湯の上部のスラグを除去した後、凝固させ、得られたインゴットを微粉砕した。Ge−Si合金インゴットは固溶体であり、非常に脆いので容易に粉砕できた。
このようにして得たGe−Si合金粉末を、さらに真空加圧焼結法により950°C、面圧250〜300kgf/cm2で、2時間焼結した。
得られた焼結体の表面を平面研削盤で表面層を除去し、ターゲットを作製した。アルキメデス法で密度を測定し、さらにXRDで結晶構造解析した。このGe−Siターゲットの不純物を化学分析した結果を、表1に示す。
ターゲット中のガス成分である酸素は300wtppm、炭素20wtppm、窒素20wtppm、水素1wtppm以下、硫黄1wtppm以下であった。また、ターゲットの相対密度は97%であり、均一な固溶体であった。
このターゲットを使用してSi(100)基板上にDCマグネトロンスパッタして、パーティクルの発生個数及び膜厚分布を調べた。その結果を表2に示す。
【0019】
【表1】
【0020】
(実施例2)
実施例1で得たGe粉末800gと同様のSi粉末200g及びB粉末0.1gを実施例1と同様に、真空中で石英アンプル中に封入した。
このGe粉末及びSi粉末を封入した石英アンプルを1150°Cに加熱し、溶解した。これを急冷してインゴットを得た。これをさらに微粉砕した。
同様にGe−Si−B合金インゴットは固溶体であり非常に脆いので、容易に粉砕できた。これを、真空加圧焼結法により950°C、面圧250〜300kgf/cm2で、2時間焼結した。
得られた焼結体の表面を平面研削盤で表面層を除去し、ターゲットを作製した。また、アルキメデス法で密度を測定し、さらにXRDで結晶構造解析した。また、このGe−Si−Bターゲットの不純物を化学分析した結果を、表1に示す。
ターゲット中のガス成分である酸素は400wtppm、炭素30wtppm、窒素10wtppm以下、水素1wtppm以下、硫黄1wtppm以下であった。また、ターゲットの相対密度は96%であり、均一な固溶体であった。
このターゲットを使用してSi(100)基板上にDCマグネトロンスパッタして、パーティクルの発生個数及び膜厚分布を調べた。その結果を表2に示す。
【0021】
【表2】
【0022】
(比較例1)
ボールミルで粉砕したSi粉末20gとGe粉末80gを混合し、この混合粉末を黒鉛モールドに充填し、真空雰囲気中で950°C、面圧250〜300kgf/cm2で、2時間焼結した。
得られた焼結体の表面を平面研削盤で表面層を除去し、ターゲットを作製した。また、アルキメデス法で密度を測定し、さらにXRDで結晶構造解析した。
ターゲット中のガス成分である酸素は820wtppm、炭素100wtppm、窒素70wtppm、水素40wtppm、硫黄40wtppmであった。また、ターゲットの相対密度は85%であった。
組織観察したところ、組織が不均一となっており、Siリッチ相とGeリッチ相の相が観察された。
このターゲットを使用してスパッタリングを実施し、パーティクルの発生個数及び膜厚分布を調べた。その結果を表2に示す。
【0023】
表1に示すように、本発明の実施例においては、ガス成分を除く不純物含有量が10wtppm以下であり、また酸素等のガス成分含有量も低く、相対密度はいずれも95%以上、膜の均一性(ユニフォーミティ、3σ)が良好、パーティクルの発生は著しく低く、スパッタ性が良好であるという結果が得られた。
これに対して、比較例はSiリッチ相とGeリッチ相の相が観察され、組織が不均一であり、不純物含有量が高く、パーティクルの発生が顕著で、剥離し易い膜が形成された。そして、これらはスパッタ成膜の品質を低下させる原因となった。
【0024】
【発明の効果】
本発明の高純度Si−Ge系合金ターゲットは、不純物が少なく、成膜時における厚膜の均一化が可能であり、またパーティクルの発生が少なく、ユニフォーミティと膜組成が均一で、スパッタ特性が良好であるという優れた効果を有し、さらに該ターゲットを安定して製造できる著しい効果を有する。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a high-purity Si-Ge-based sputtered film for a semiconductor device or a high-purity Si-Ge for producing them, which has semiconductor characteristics and can be used as a material for optical communication devices and solar cells. The present invention relates to an alloy base target and a manufacturing method thereof.
[0002]
[Prior art]
Conventionally, silicon is the most popular material for LSI semiconductors, but compound semiconductors such as indium / phosphorus and gallium / arsenic have been used for optical communications (LE / LED).
However, indium has a very short resource life, about 20 years is said to be a minable year, and arsenic is a highly toxic element as is well known. For this reason, it must be said that the semiconductor materials for optical communication that are currently widely used have a great problem in use.
In particular, gallium / arsenic semiconductor elements used in mobile phones with a short product life are highly toxic arsenic, and disposal of these elements is a major problem.
[0003]
Under such circumstances, it has been found that the Si—Ge-based material has semiconductor characteristics, and it has been pointed out that it is a preferable optical communication element or solar cell material. The great advantage of this Si-Ge material is that it is abundant on the earth, and there is no concern about toxicity, etc., but further, semiconductor characteristics equivalent to those of conventional compound semiconductors can be obtained and There is a great advantage that it is inexpensive.
However, this Si—Ge-based material is not without problems, and a technology for producing a high-purity and high-quality material has not been established at present.
[0004]
Currently, as a technique for forming a thin film made of a Si—Ge based material, a Si—Ge based semiconductor target is formed on a Si substrate by sputtering a Si—Ge based material target.
The main impurities contained in the thin film made of Si-Ge material include transition metal elements such as Fe, Ni, Co and Cu, alkali metal elements such as Na and K, radioactive elements such as U and Th, and other Examples of the impurities include heavy metal elements such as Al, Cr, Ca, and Mg or light metal elements.
The transition metal element causes troubles at the interface junction, the alkali metal element easily diffuses and easily moves, leading to deterioration of the MOS-LSI interface characteristics, and the radioactive element emits alpha rays and softens. It is known to cause an error. In addition, the presence of heavy metal elements or light metal elements increases the electrical resistance and decreases the reliability of the operation performance of the semiconductor element.
[0005]
In addition, gas components such as oxygen, carbon, nitrogen, hydrogen, and sulfur also cause arcing and particle generation during the sputtering of the Si—Ge-based material target, and increase the electrical resistance.
However, Si-Ge-based materials are difficult to be highly purified, and even if they are once highly purified, there are problems in that the impurities as described above are easily mixed in the manufacturing process of the sputtering target and it is difficult to maintain the purity. Therefore, when a Si—Ge based material target is sputtered to form a Si—Ge based semiconductor film on a Si substrate, improvement of the purity of the target is a very important problem.
[0006]
In general, when forming a film by sputtering, in order to increase the film forming speed and increase the production efficiency, the film forming area is expanded, that is, sputtering is performed using a target having a large area. At this time, the generation of particles or the uniformity of the film thickness becomes a big problem.
Since the properties and structure of the Si-Ge-based material target in the manufacturing process are directly reflected in sputtering, it has been difficult to form a predetermined film composition uniformly on a large substrate, and arcing and particle generation are unavoidable. It was.
[0007]
[Problems to be solved by the invention]
In order to solve the above problems, the present invention has few impurities, can make a thick film uniform during film formation, has few particles, has uniform uniformity and film composition, and has sputtering characteristics. It is an object to obtain a good high-purity Si-Ge-based alloy target, a method capable of stably manufacturing the high-purity target, and a Si-Ge-based sputtered film having a uniform film thickness, less leakage current, and excellent film characteristics And
[0008]
[Means for Solving the Problems]
The present invention
1. 1. A high-purity Si—Ge alloy target characterized by having a purity of 5N (99.999 wt%) or more excluding gas components. As impurities in the target, transition metal elements such as Fe, Ni, Co, and Cu are each 2 wtppm or less, alkali metal elements such as Na and K are each 1 wtppm or less, and the content of radioactive elements such as U and Th is 1 wtppb or less, 2. The high-purity Si—Ge alloy target as described in 1 above, wherein the content of heavy metals or light metals such as Al, Cr, Ca and Mg is 1 wtppm or less as other impurities. 3. The high-purity Si—Ge alloy target according to 1 or 2 above, wherein oxygen as a gas component in the target is 1000 wtppm or less. The high purity according to each of the above 1 to 3, wherein the gas components in the target are 50 wtppm or less of carbon, 50 wtppm or less of nitrogen, 50 wtppm or less of hydrogen, and 50 wtppm or less of sulfur (excluding cases where all are dopants). 4. Si—Ge alloy target 5. The high-purity Si—Ge based alloy target according to each of the above 1 to 4, wherein the target has a relative density of 90% or more. 6. The high-purity Si—Ge alloy target according to each of 1 to 5 above, which has a solid solution structure. The high-purity Si—Ge alloy target according to each of 1 to 5 above, which contains a dopant such as B and C in a range in which the dopant is solid-dissolved.
[0009]
The present invention also provides:
8). High-purity Si and high-purity Ge, which are the main components, are melted and cast in a high vacuum to produce an alloy ingot, which is pulverized to produce a Si-Ge alloy fine powder, which is then sintered. 8. A method for producing a high-purity Si-Ge alloy target characterized in that 9. The method for producing a high purity Si—Ge alloy target as described in 8 above, wherein a dopant such as B and C is contained in a range in which the dopant is dissolved. A Ge raw material is dissolved in an acid such as aqua regia and recovered as GeCl 4 , and this is reduced with hydrogen to obtain a 5N level Ge powder. The 5N level Ge powder and the 5N level Si are mixed in a vacuum. 10. A method for producing a high-purity Si—Ge alloy target as described in 8 or 9 above, wherein 11. The method for producing a high purity Si—Ge alloy target as described in 10 above, wherein the melt is mixed with agglomerated Si having an average particle diameter of 1 mm or more. The method for producing a high-purity Si—Ge alloy target according to each of the above 8 to 11, wherein the fine powder is sintered by hot pressing, hot isostatic pressing or discharge plasma sintering.
[0010]
The present invention also provides:
13. 14. A high-purity Si—Ge-based sputtered film characterized by having a purity of 5N (99.999 wt%) or more excluding gas components. As impurities, transition metal elements such as Fe, Ni, Co and Cu are each 2 wtppm or less, alkali metal elements such as Na and K are each 1 wtppm or less, the content of radioactive elements such as U and Th is 1 wtppb or less, and other impurities 14. The high-purity Si-Ge-based sputtered film according to the above 13, wherein the content of heavy metal elements such as Al, Cr, Ca, Mg or light metal elements is 1 wtppm or less. 15. The high purity Si—Ge based sputtered film according to the above 13 or 14, wherein oxygen as a gas component is 1000 wtppm or less. The high-purity Si-Ge according to each of the above 13 to 15, which is a gas component of carbon 50 wtppm or less, nitrogen 50 wtppm or less, hydrogen 50 wtppm or less, and sulfur 50 wtppm or less (except when any of the dopants is used). System sputtered film 17. 17. The high-purity Si—Ge-based sputtered film according to each of the above 13 to 16, which has a solid solution structure. The high-purity Si—Ge-based sputtered film according to each of the above 13 to 17, wherein a dopant such as B or C is contained in a range in which the dopant is dissolved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The Si—Ge based alloy target of the present invention includes a component range in a range having semiconductor characteristics. It is usually 5 to 50 wt% Si—Ge, and includes a Si—Ge target containing a small amount of a dopant such as B and C in a solid solution range. The Si—Ge based alloy target of the present invention has a structure of Si—Ge solid solution.
In the production of the target of the present invention, a 3N level Ge raw material is dissolved in an acid such as aqua regia and recovered as GeCl 4 , and this is hydrogen reduced to obtain a 5N level Ge powder. After hydrogen reduction, this can be once dissolved in a vacuum to remove impurities such as slag, thereby further improving the purity.
Next, the 5N level Ge powder and the 5N level Si are mixed and dissolved in a vacuum. Since 5N level Si may cause contamination if fine powder having an average particle size of 1 mm or less is used, it is desirable to use bulk Si (average particle size of 1 mm or more).
[0012]
The above-described high-purity Si and high-purity Ge as the main components are melted and cast in a high vacuum to produce an alloy ingot. During melting, the slag floating on the surface is removed, and the purity is further improved. The ingot is pulverized to produce a Si—Ge alloy fine powder. This fine powder is a solid solution. The Si-Ge alloy fine powder is sintered to obtain a high purity Si-Ge alloy target. This target can contain dopants such as B and C as long as they are dissolved.
The fine powder can be sintered by hot pressing, hot isostatic pressing or discharge plasma sintering. Through the above steps, a high-purity Si—Ge alloy target is manufactured.
[0013]
By the above production method, the target of the present invention can obtain a high purity Si—Ge alloy target having a purity of 5N (99.999 wt%) or more, excluding gas components. As a result, a high-purity Si-Ge alloy target can be obtained, in which a thick film can be made uniform during film formation, particle generation is small, uniformity and film composition are uniform, and sputtering characteristics are good. It is done.
Further, as impurities in the target, transition metal elements such as Fe, Ni, Co, and Cu are each 2 wtppm or less, alkali metal elements such as Na and K are each 1 wtppm or less, and the content of radioactive elements such as U and Th is 1 wtppb Hereinafter, as other impurities, it is possible to obtain a high-purity Si—Ge alloy target having a heavy metal element or light metal element content of 1 wtppm or less, such as Al, Cr, Ca, Mg, etc. Film formation with excellent properties is possible.
[0014]
Oxygen which is a gas component in the target can be 1000 wtppm or less, preferably 600 ppm or less, and more preferably 150 ppm or less. As a result, the generation of particles can be further suppressed, and film formation with uniform uniformity and film composition becomes possible.
Further, the gas components in the target can be set to 50 wtppm or less of carbon, 50 wtppm or less of nitrogen, 50 wtppm or less of hydrogen, and 50 wtppm or less of sulfur (except for the case where any of them is used as a dopant). it can.
The relative density of the target can be 90% or more, and further 95% or more, and a high-purity Si—Ge alloy target having a solid solution structure can be obtained.
Furthermore, the average crystal grain size of the target structure can be 300 μm or less, preferably 150 μm or less, and more preferably 75 μm or less. By this, generation of arcing and particles can be further suppressed, and a film having stable characteristics can be obtained. be able to.
[0015]
In sputtering, since a stable bias voltage can be applied to the target, the plasma density can be easily increased, and the sputtering gas pressure can be kept low, so that a good film with little gas damage can be obtained.
As described above, it is possible to form a film having excellent film characteristics with less generation of particles, uniform uniformity and film composition, and less leakage current.
The present invention includes all high-purity Si-Ge-based sputtered films formed using a high-purity Si-Ge-based alloy target.
[0016]
[Examples and Comparative Examples]
Next, examples will be described. In addition, a present Example is for showing an example of invention, This invention is not restrict | limited to these Examples. That is, other aspects and modifications included in the technical idea of the present invention are included.
[0017]
Example 1
1500 g of Ge with a purity level of 3N is dissolved in aqua regia and recovered as GeCl 4 . Next, this was reduced with hydrogen to obtain 1200 g of Ge powder.
This was melted in a vacuum at 1000 ° C. in a quartz boat. After removing the slag floating on the upper part, the solidified product was pulverized in an agate mortar to obtain 800 g of Ge powder.
On the other hand, a commercially available 5N level polycrystalline Si powder was sieved, and 200 g of particles having an average particle diameter of 1 mm or more were weighed. These powders were sealed in a quartz ampule in a vacuum.
[0018]
Next, the quartz ampule enclosing the Ge powder and Si particles was heated to 1050 ° C. and dissolved. The slag at the top of the molten metal was removed and then solidified, and the resulting ingot was finely pulverized. The Ge—Si alloy ingot was a solid solution and was very brittle and could be easily pulverized.
The Ge—Si alloy powder thus obtained was further sintered for 2 hours at 950 ° C. and a surface pressure of 250 to 300 kgf / cm 2 by a vacuum pressure sintering method.
The surface layer of the obtained sintered body was removed with a surface grinder to prepare a target. The density was measured by the Archimedes method, and the crystal structure was further analyzed by XRD. Table 1 shows the results of chemical analysis of impurities in this Ge-Si target.
Oxygen as a gas component in the target was 300 wtppm, carbon 20 wtppm, nitrogen 20 wtppm, hydrogen 1 wtppm or less, and sulfur 1 wtppm or less. Moreover, the relative density of the target was 97%, and it was a uniform solid solution.
Using this target, DC magnetron sputtering was performed on a Si (100) substrate, and the number of generated particles and the film thickness distribution were examined. The results are shown in Table 2.
[0019]
[Table 1]
[0020]
(Example 2)
In the same manner as in Example 1, 200 g of Si powder similar to 800 g of Ge powder obtained in Example 1 and 0.1 g of B powder were sealed in a quartz ampule.
The quartz ampule encapsulating the Ge powder and Si powder was heated to 1150 ° C. and dissolved. This was rapidly cooled to obtain an ingot. This was further pulverized.
Similarly, the Ge—Si—B alloy ingot was a solid solution and very brittle, and could be easily pulverized. This was sintered by vacuum pressure sintering at 950 ° C. and a surface pressure of 250 to 300 kgf / cm 2 for 2 hours.
The surface layer of the obtained sintered body was removed with a surface grinder to prepare a target. Further, the density was measured by Archimedes method, and the crystal structure was further analyzed by XRD. Table 1 shows the results of chemical analysis of impurities in the Ge—Si—B target.
Oxygen as a gas component in the target was 400 wtppm, carbon 30 wtppm, nitrogen 10 wtppm or less, hydrogen 1 wtppm or less, and sulfur 1 wtppm or less. Moreover, the relative density of the target was 96%, and it was a uniform solid solution.
Using this target, DC magnetron sputtering was performed on a Si (100) substrate, and the number of generated particles and the film thickness distribution were examined. The results are shown in Table 2.
[0021]
[Table 2]
[0022]
(Comparative Example 1)
20 g of Si powder pulverized by a ball mill and 80 g of Ge powder were mixed, and this mixed powder was filled in a graphite mold and sintered in a vacuum atmosphere at 950 ° C. and a surface pressure of 250 to 300 kgf / cm 2 for 2 hours.
The surface layer of the obtained sintered body was removed with a surface grinder to prepare a target. Further, the density was measured by Archimedes method, and the crystal structure was further analyzed by XRD.
Oxygen as a gas component in the target was 820 wtppm, carbon 100 wtppm, nitrogen 70 wtppm, hydrogen 40 wtppm, and sulfur 40 wtppm. The relative density of the target was 85%.
When the structure was observed, the structure was not uniform, and a Si-rich phase and a Ge-rich phase were observed.
Sputtering was performed using this target, and the number of particles generated and the film thickness distribution were examined. The results are shown in Table 2.
[0023]
As shown in Table 1, in the examples of the present invention, the content of impurities excluding gas components is 10 wtppm or less, the content of gas components such as oxygen is low, the relative density is 95% or more, The results showed that the uniformity (uniformity, 3σ) was good, the generation of particles was remarkably low, and the sputterability was good.
On the other hand, in the comparative example, a Si-rich phase and a Ge-rich phase were observed, the structure was non-uniform, the impurity content was high, the generation of particles was remarkable, and a film that was easily peeled was formed. These have caused the quality of sputter film formation to deteriorate.
[0024]
【The invention's effect】
The high-purity Si-Ge alloy target of the present invention has few impurities, can make a thick film uniform during film formation, has few particles, has a uniform uniformity and film composition, and has a sputtering characteristic. It has an excellent effect of being good, and also has a remarkable effect that the target can be stably manufactured.
Claims (18)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2002175815A JP4213408B2 (en) | 2002-06-17 | 2002-06-17 | High purity Si-Ge alloy target and manufacturing method thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2002175815A JP4213408B2 (en) | 2002-06-17 | 2002-06-17 | High purity Si-Ge alloy target and manufacturing method thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2004018946A true JP2004018946A (en) | 2004-01-22 |
JP4213408B2 JP4213408B2 (en) | 2009-01-21 |
Family
ID=31174365
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2002175815A Expired - Lifetime JP4213408B2 (en) | 2002-06-17 | 2002-06-17 | High purity Si-Ge alloy target and manufacturing method thereof |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP4213408B2 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010084733A1 (en) * | 2009-01-20 | 2010-07-29 | 信越ポリマー株式会社 | Radio wave-transmitting decorative member and method for producing same |
US9493870B2 (en) | 2009-03-17 | 2016-11-15 | Shin-Etsu Polymer Co., Ltd. | Radio wave-transmitting decorative film and decorative member using same |
TWI616938B (en) * | 2015-09-24 | 2018-03-01 | Toyo Aluminium Kk | Paste composition and method for forming silicon germanium layer |
KR20230164078A (en) | 2021-03-31 | 2023-12-01 | 도요 알루미늄 가부시키가이샤 | Paste composition and method of forming germanium compound layer |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109722542B (en) * | 2019-03-18 | 2020-12-04 | 云南临沧鑫圆锗业股份有限公司 | Method for treating and recycling germanium-containing gallium arsenide waste |
-
2002
- 2002-06-17 JP JP2002175815A patent/JP4213408B2/en not_active Expired - Lifetime
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010084733A1 (en) * | 2009-01-20 | 2010-07-29 | 信越ポリマー株式会社 | Radio wave-transmitting decorative member and method for producing same |
JP2010188713A (en) * | 2009-01-20 | 2010-09-02 | Shin Etsu Polymer Co Ltd | Radio wave-transmitting decorative member and method of manufacturing the same |
CN102282288A (en) * | 2009-01-20 | 2011-12-14 | 信越聚合物株式会社 | Radio wave-transmitting decorative member and method for producing same |
US8816932B2 (en) | 2009-01-20 | 2014-08-26 | Shin-Etsu Polymer Co., Ltd. | Radio wave transmitting decorative member and the production method thereof |
US9493870B2 (en) | 2009-03-17 | 2016-11-15 | Shin-Etsu Polymer Co., Ltd. | Radio wave-transmitting decorative film and decorative member using same |
TWI616938B (en) * | 2015-09-24 | 2018-03-01 | Toyo Aluminium Kk | Paste composition and method for forming silicon germanium layer |
KR20180059474A (en) | 2015-09-24 | 2018-06-04 | 도요 알루미늄 가부시키가이샤 | Paste composition and method for forming a silicon germanium layer |
US10916423B2 (en) | 2015-09-24 | 2021-02-09 | Toyo Aluminium Kabushiki Kaisha | Paste composition and method for forming silicon germanium layer |
KR20230164078A (en) | 2021-03-31 | 2023-12-01 | 도요 알루미늄 가부시키가이샤 | Paste composition and method of forming germanium compound layer |
Also Published As
Publication number | Publication date |
---|---|
JP4213408B2 (en) | 2009-01-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4388263B2 (en) | Iron silicide sputtering target and manufacturing method thereof | |
JP5144766B2 (en) | Cu-Ga sintered compact sputtering target and method for producing the same | |
JP5818139B2 (en) | Cu-Ga alloy target material and method for producing the same | |
JPWO2011010529A1 (en) | Cu-Ga alloy sintered body sputtering target, method for producing the target, light absorption layer produced from Cu-Ga alloy sintered body target, and CIGS solar cell using the light absorption layer | |
CN102203954A (en) | Chalcogenide alloy sputter targets for photovoltaic applications and methods of manufacturing the same | |
JP2010280944A (en) | Cu-Ga ALLOY, SPUTTERING TARGET, METHOD FOR PRODUCING THE Cu-Ga ALLOY, AND METHOD FOR PRODUCING THE SPUTTERING TARGET | |
JP2008163367A (en) | Method of manufacturing sputtering target of cu-in-ga-se-based quaternary alloy | |
US20110284372A1 (en) | Cu-Ga ALLOY MATERIAL, SPUTTERING TARGET, METHOD OF MAKING Cu-Ga ALLOY MATERIAL, Cu-In-Ga-Se ALLOY FILM, AND METHOD OF MAKING Cu-In-Ga-Se ALLOY FILM | |
JP2015127293A (en) | Oxide sintered compact, sputtering target, and method for production thereof | |
US20120009373A1 (en) | Hybrid Silicon Wafer and Method of Producing the Same | |
KR20140097131A (en) | Sputtering target and method for producing same | |
KR100807525B1 (en) | Iron silicide powder and method for production thereof | |
JP2009120863A (en) | MANUFACTURING METHOD OF Cu-In-Ga TERNARY SINTERED ALLOY SPUTTERING TARGET | |
TWI666333B (en) | Cu-ga alloy sputtering target and method of producing the same | |
JP2009120862A (en) | Cu-In-Ga TERNARY SINTERED ALLOY SPUTTERING TARGET, AND ITS MANUFACTURING METHOD | |
KR20140106468A (en) | MoTi TARGET MATERIAL AND METHOD FOR MANUFACTURING FOR THE SAME | |
JP4213408B2 (en) | High purity Si-Ge alloy target and manufacturing method thereof | |
JP5418832B2 (en) | Method for producing Cu-In-Ga-Se quaternary alloy sputtering target | |
JP2005330591A (en) | Sputtering target | |
TWI669283B (en) | Oxide sintered body and sputtering target material and their manufacturing method | |
KR20150040294A (en) | Sputtering target and method for producing same | |
US9982334B2 (en) | Polycrystalline silicon sputtering target | |
JP2015045060A (en) | MANUFACTURING METHOD OF Cu-BASED POWDER, AND MANUFACTURING METHOD OF Cu-BASED SPUTTERING TARGET MATERIAL USING THE SAME | |
JPWO2015046319A1 (en) | In alloy sputtering target, manufacturing method thereof, and In alloy film | |
JPH1161392A (en) | Production of sputtering target for forming ru thin film |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050308 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20071221 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080108 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080221 |
|
A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080826 |
|
A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080930 |
|
TRDD | Decision of grant or rejection written | ||
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20081028 |
|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20081030 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111107 Year of fee payment: 3 |
|
R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 Ref document number: 4213408 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111107 Year of fee payment: 3 |
|
S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313111 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111107 Year of fee payment: 3 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20111107 Year of fee payment: 3 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121107 Year of fee payment: 4 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20121107 Year of fee payment: 4 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131107 Year of fee payment: 5 |
|
S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
EXPY | Cancellation because of completion of term |