JPH08319186A - Cvd-siliconcarbide-coated member - Google Patents
Cvd-siliconcarbide-coated memberInfo
- Publication number
- JPH08319186A JPH08319186A JP14818795A JP14818795A JPH08319186A JP H08319186 A JPH08319186 A JP H08319186A JP 14818795 A JP14818795 A JP 14818795A JP 14818795 A JP14818795 A JP 14818795A JP H08319186 A JPH08319186 A JP H08319186A
- Authority
- JP
- Japan
- Prior art keywords
- cvd
- sic
- film
- oxygen
- base material
- 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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ＣＶＤ−ＳｉＣ被覆部
材に関し、詳しくは、半導体製造における熱処理工程に
使用されるサセプター、ウエハボート、ダミーウエハ等
の部材として利用されるＣＶＤ−ＳｉＣ被覆部材に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CVD-SiC coated member, and more particularly to a CVD-SiC coated member used as a member such as a susceptor, a wafer boat and a dummy wafer used in a heat treatment process in semiconductor manufacturing.
【０００２】[0002]
【従来の技術】従来から、半導体製造工程においては、
表面上にＣＶＤ−ＳｉＣ膜を被覆したＣＶＤ−ＳｉＣ被
覆部材が多く用いられている。ＣＶＤ−ＳｉＣ膜は、
（１）耐熱性、耐食性に優れる、（２）金属不純物の含
有量が極めて少ない、（３）基材内部の金属等の不純物
のウエハへの拡散を抑制できる、（４）緻密質で内在気
孔を有さず、高硬度で、研磨特性に優れる等の優れた特
性を有している。ＣＶＤ−ＳｉＣ被覆部材はこの表面の
ＣＶＤ−ＳｉＣ膜の特性をそのまま部材特性として保持
し、特に、半導体製造用の熱処理工程用治具として好適
に用いられている。熱処理工程用治具としてのＣＶＤ−
ＳｉＣ被覆部材は、一般に、基材上に熱ＣＶＤ処理法で
約２０μｍ以上の膜厚で上記ＣＶＤ−ＳｉＣ膜が被覆さ
れている。このＣＶＤ−ＳｉＣ被覆部材の基材としては
各種の耐熱材が用いられるが、従来、ＳｉＣ膜との密着
性を確保するため等方性カーボン、炭化珪素（ＳｉＣ）
と炭素（Ｃ）との混合物に珪素（Ｓｉ）を反応させて得
られる反応焼結ＳｉＣ（Ｓｉ−ＳｉＣ）、常圧焼結Ｓｉ
Ｃ等の熱膨張係数がＣＶＤ−ＳｉＣに近似するものが用
いられている。2. Description of the Related Art Conventionally, in the semiconductor manufacturing process,
A CVD-SiC coating member having a surface coated with a CVD-SiC film is often used. The CVD-SiC film is
(1) Heat resistance and corrosion resistance are excellent, (2) Content of metal impurities is extremely low, (3) Diffusion of impurities such as metal inside the substrate to the wafer can be suppressed, (4) Dense and internal pores It has excellent characteristics such as high hardness and excellent polishing characteristics. The CVD-SiC coated member retains the characteristics of the CVD-SiC film on the surface as it is as a member characteristic, and is particularly preferably used as a jig for a heat treatment process for semiconductor manufacturing. CVD as a jig for heat treatment process
In the SiC-coated member, a CVD-SiC film is generally coated on a base material by a thermal CVD treatment method so as to have a film thickness of about 20 μm or more. Various heat-resistant materials are used as the base material of the CVD-SiC coated member, but conventionally, isotropic carbon or silicon carbide (SiC) is used to ensure adhesion with the SiC film.
Sintered SiC (Si-SiC) obtained by reacting silicon (Si) with a mixture of carbon and carbon (C), normal pressure sintered Si
A material having a coefficient of thermal expansion similar to that of CVD-SiC such as C is used.
【０００３】[0003]
【発明が解決しようとする課題】しかし、従来から用い
られている熱膨張係数の近似する基材の殆どは不純物を
含有し、ＣＶＤ−ＳｉＣ膜に不純物拡散抑制作用がある
とはいえ、基材に含有される不純物がＣＶＤ−ＳｉＣ膜
を通過して外部に拡散して汚染源となることが問題にさ
れている。そのため、例えば、特開昭６４−６１３７６
号公報では、不純物含有のＳｉＣ質系基材を用い、ＣＶ
Ｄ−ＳｉＣ膜との中間にシリカ膜を形成することことを
提案し、不純物の拡散防止を著しく向上させている。ま
た、比較的不純物の少ない高純化処理した等方性カーボ
ンは、気孔率が高く内部に残留ガスを有するためＣＶＤ
で表面被覆した場合、内部ガスが膨張する等によりＣＶ
Ｄ−ＳｉＣ膜を剥離させることがある。上記従来のＣＶ
Ｄ−ＳｉＣ被覆部材が、ＳｉＣ膜の不純物拡散抑制効果
の下に不純物含有基材の使用を前提とし、密着性から熱
膨張係数を合わせるように基材を選択していることに対
し、本発明は、治具等の装置部材からの不純物拡散によ
る半導体汚染をより一層防止することを目的とし、密着
性を基準にＳｉＣの熱膨張係数に合う基材を選択するも
のでなく、不純物の多少を基準に基材を選択すると共
に、基材とＣＶＤ−ＳｉＣ膜との密着性も良好となるよ
うにＣＶＤ−ＳｉＣ膜の熱膨張係数を制御することを企
図した。However, most of conventionally used base materials having a similar thermal expansion coefficient contain impurities, and although the CVD-SiC film has an impurity diffusion suppressing effect, It has been a problem that the impurities contained in (3) pass through the CVD-SiC film and diffuse to the outside to become a pollution source. Therefore, for example, Japanese Patent Laid-Open No. 64-61376.
In the publication, a SiC-based base material containing impurities is used, and CV
It is proposed to form a silica film in the middle of the D-SiC film, and the diffusion prevention of impurities is significantly improved. Further, the highly purified isotropic carbon having relatively few impurities has a high porosity and has a residual gas inside, so that it is CVD.
When the surface is coated with CV, the internal gas expands, etc.
The D-SiC film may be peeled off. Above-mentioned conventional CV
According to the present invention, the D-SiC coating member selects the base material so that the coefficient of thermal expansion is matched from the adhesiveness on the assumption that the base material containing the impurity is used under the effect of suppressing the impurity diffusion of the SiC film. Aims to further prevent semiconductor contamination due to impurity diffusion from device members such as jigs, and does not select a base material that matches the coefficient of thermal expansion of SiC on the basis of adhesiveness, but does not select the amount of impurities. It was attempted to select the base material as a reference and control the thermal expansion coefficient of the CVD-SiC film so that the adhesion between the base material and the CVD-SiC film was good.
【０００４】[0004]
【課題を解決するための手段】本発明によれば、ＣＶＤ
−ＳｉＣより小さな熱膨張係数を有する基材表面をＣＶ
Ｄにより酸素含有ＳｉＣ膜で被覆してなり、該酸素含有
ＳｉＣ膜の酸素濃度が膜表面から基材方向に連続的にま
たは段階的に増加すると共に、表面層で０．０５重量％
以下で、且つ、該基材との接合面層で２５重量％以下で
あることを特徴とするＣＶＤ−ＳｉＣ被覆部材が提供さ
れる。上記本発明のＣＶＤ−ＳｉＣ被覆部材において、
前記ＳｉＣ膜の含有酸素濃度が、前記表面層から膜厚方
向に１重量％／μｍ以下の濃度勾配を有することが好ま
しく、また表面層が１０μｍ以上の厚さであることが好
ましく、さらに、急激なヒートサイクルに対する高い耐
熱衝撃性を得るためには、０．５〜０．１重量％／μｍ
とすることが好ましい。また、前記基材がシリコン結晶
体であることが好ましい。According to the present invention, CVD
-CV is applied to the surface of the substrate having a thermal expansion coefficient smaller than that of SiC.
D is coated with an oxygen-containing SiC film, the oxygen concentration of the oxygen-containing SiC film increases continuously or stepwise from the film surface toward the substrate, and 0.05% by weight in the surface layer.
A CVD-SiC coated member is provided below, which is 25% by weight or less in a bonding surface layer with the base material. In the above CVD-SiC coated member of the present invention,
The concentration of oxygen contained in the SiC film preferably has a concentration gradient of 1% by weight / μm or less in the film thickness direction from the surface layer, and the surface layer preferably has a thickness of 10 μm or more. 0.5-0.1% by weight / μm in order to obtain high thermal shock resistance against various heat cycles
It is preferable that Further, it is preferable that the base material is a silicon crystal body.
【０００５】[0005]
【作用】本発明は上記のように構成され、熱膨張係数に
よることなく基材を選択することができ、高純度材質を
選択して基材に使用でき、半導体製造用治具等のＣＶＤ
−ＳｉＣ被覆部材として従来に比し、不純物拡散をより
一層低減することができる。また、ＣＶＤ−ＳｉＣ膜中
に、ＣＶＤ−ＳｉＣ膜の熱膨張が基材に合うようにその
濃度を制御して酸素を含有させ、且つ、表面から基材方
向に濃度勾配を有するように制御するため、基材とＣＶ
Ｄ−ＳｉＣ膜との密着性を向上させることができる。し
かも、表面層には酸素を含有せず、ＳｉＣ単一組成とな
るため化学的安定等のＣＶＤ−ＳｉＣ膜の優れた特性も
保持することができる。このため、本発明のＣＶＤ−Ｓ
ｉＣ被覆部材は、近年の高集積化半導体を高純度で、且
つ、高歩留で円滑に安定して製造することができ半導体
処理の信頼性を著しく高めることができる。The present invention is configured as described above, and the base material can be selected without depending on the coefficient of thermal expansion, a high-purity material can be selected and used for the base material, and CVD for semiconductor manufacturing jigs and the like can be performed.
As an SiC-coated member, it is possible to further reduce impurity diffusion as compared with the conventional case. Further, in the CVD-SiC film, the concentration is controlled so that the thermal expansion of the CVD-SiC film matches the base material to contain oxygen, and the concentration is controlled so as to have a concentration gradient from the surface toward the base material. Therefore, the base material and CV
The adhesion with the D-SiC film can be improved. Moreover, since the surface layer does not contain oxygen and has a single composition of SiC, excellent characteristics of the CVD-SiC film such as chemical stability can be maintained. Therefore, the CVD-S of the present invention
The iC coating member can manufacture a highly integrated semiconductor of recent years with high purity, high yield, and smoothly and stably, and can significantly improve the reliability of semiconductor processing.
【０００６】以下、本発明について詳しく説明する。本
発明のＣＶＤ−ＳｉＣ被覆部材において、ＣＶＤ法で酸
素含有ＳｉＣを被覆する基材は、ＣＶＤ−ＳｉＣ膜より
熱膨張係数が小さいものを適宜選択することができる。
ＣＶＤ−ＳｉＣ膜中に酸素を含有させてＣＶＤ−ＳｉＣ
膜の熱膨張係数を低下させることができ、基材の熱膨張
係数に合わせるためである。ＣＶＤ−ＳｉＣ膜中に所定
量の酸素を制御して含有させることにより、実質的にＳ
ｉＣとＳｉＯ2 との複合体となし、ＣＶＤ−ＳｉＣと石
英ガラスの熱膨張係数の範囲にある任意の熱膨張係数を
有するＣＶＤ−ＳｉＣ膜を形成することができる。この
範囲のＣＶＤ−ＳｉＣ膜の熱膨張係数より小さい基材と
しては、特に、シリコン単結晶及びシリコン多結晶のシ
リコン結晶体を用いることが好ましい。シリコン結晶体
を基材として用いた本発明のＣＶＤ−ＳｉＣ被覆部材
は、特に密着性に優れ熱的に安定な部材となる。The present invention will be described in detail below. In the CVD-SiC coated member of the present invention, the base material coated with the oxygen-containing SiC by the CVD method can be appropriately selected from those having a smaller thermal expansion coefficient than the CVD-SiC film.
CVD-SiC film containing oxygen
This is because the coefficient of thermal expansion of the film can be lowered and the coefficient of thermal expansion of the substrate can be adjusted. By controlling and containing a predetermined amount of oxygen in the CVD-SiC film, S
A composite of iC and SiO 2 can be formed to form a CVD-SiC film having an arbitrary coefficient of thermal expansion within the range of the coefficients of thermal expansion of CVD-SiC and quartz glass. As the base material having a thermal expansion coefficient smaller than that of the CVD-SiC film in this range, it is particularly preferable to use silicon single crystal or silicon polycrystal silicon crystal. The CVD-SiC coated member of the present invention using a silicon crystal as a base material has a particularly excellent adhesion and becomes a thermally stable member.
【０００７】本発明において、上記ＣＶＤ−ＳｉＣ膜中
に含有させる酸素量は、ＳｉＣ膜の厚さ、基材の種類等
によって異なるが、ＣＶＤ−ＳｉＣ被覆部材の表面層、
例えば表面より１０μｍ〜１００μｍの表面域におい
て、酸素濃度を０．０５重量％以下に保持することが好
ましく、さらには、０．０１重量％以下とすることがよ
り好ましい。表面層はＳｉＣ単体の組成とすることによ
り、耐蝕性等ＣＶＤ−ＳｉＣ膜の優れた特性を保持で
き、半導体製造の熱処理工程の各種部材として従来と同
様に好適に使用することができる。本発明においては、
上記のようにＣＶＤ−ＳｉＣ膜表面から少なくとも厚さ
１０μｍは極微量の酸素濃度とする一方、更に、表面層
から膜内部即ち基材方向に酸素濃度を徐々に増加させ、
基材との接合面層において、その基材の熱膨張係数にほ
ぼ一致するような酸素濃度となるように制御することが
好ましい。この場合、酸素濃度は、上記ＣＶＤ−ＳｉＣ
膜表面の濃度から連続的に２５％以下まで増加させるこ
とが好ましく、特に、表面を被覆する基材を上記のシリ
コン結晶体を用いる場合には、接合面層の酸素濃度は５
〜２５重量％が好ましく、更には１０〜２０重量％がよ
り好ましい。尚、上記酸素濃度の増加は、段階的なもの
でも構わない。また、ＣＶＤ−ＳｉＣ膜の基材に向かう
厚さ方向に酸素濃度勾配は、表面層の厚さにより密着性
の良否に大きく影響されるが、一般的には、表面層の厚
さを一定とした場合には１重量％／μｍ以下が好まし
い。より好ましくは１〜０．１重量％／μｍ、更に好ま
しくは０．５〜０．１重量％／μｍである。特に、急激
なヒートサイクルに対する高い耐熱衝撃性を得るために
は酸素濃度勾配を０．５〜０．１重量％／μｍとするの
が好ましい。酸素濃度が２５％を超えたり、酸素濃度勾
配が１重量％／μｍより大きいと、いずれもＳｉＣとＳ
ｉＯ2 との熱膨張係数の差が大きくなりすぎ、膜内部で
の歪みが大きく、膜自体に亀裂や破損が発生するおそれ
が有るためである。また、酸素濃度が５重量％未満であ
ったり、酸素濃度勾配が０．１重量％／μｍ未満で小さ
過ぎると接合面付近から剥離が起こり易い。なお、本発
明のＣＶＤ−ＳｉＣ被覆部材の酸素含有ＳｉＣ層は、２
０〜１２０μｍの厚さで形成され、通常、約６０μｍで
ある。In the present invention, the amount of oxygen contained in the CVD-SiC film varies depending on the thickness of the SiC film, the type of the substrate, etc., but the surface layer of the CVD-SiC coating member,
For example, in the surface region of 10 μm to 100 μm from the surface, the oxygen concentration is preferably maintained at 0.05% by weight or less, and more preferably 0.01% by weight or less. When the surface layer is composed of a simple substance of SiC, excellent characteristics such as corrosion resistance of the CVD-SiC film can be maintained, and the surface layer can be suitably used as various members in the heat treatment step of semiconductor manufacturing as in the conventional case. In the present invention,
As described above, at least a thickness of 10 μm from the surface of the CVD-SiC film has an extremely small amount of oxygen concentration, and further, the oxygen concentration is gradually increased from the surface layer toward the inside of the film, that is, toward the substrate,
It is preferable to control the oxygen concentration in the joint surface layer with the base material so as to approximately match the thermal expansion coefficient of the base material. In this case, the oxygen concentration is the above-mentioned CVD-SiC.
It is preferable to continuously increase the concentration from the surface of the film to 25% or less. Particularly, when the above-mentioned silicon crystal is used as the base material for coating the surface, the oxygen concentration of the bonding surface layer is 5% or less.
-25 wt% is preferable, and 10-20 wt% is more preferable. The oxygen concentration may be increased stepwise. Further, the oxygen concentration gradient in the thickness direction of the CVD-SiC film toward the base material is largely influenced by the quality of the adhesiveness depending on the thickness of the surface layer, but generally, the thickness of the surface layer is constant. In that case, it is preferably 1% by weight / μm or less. It is more preferably 1 to 0.1% by weight / μm, and even more preferably 0.5 to 0.1% by weight / μm. In particular, in order to obtain high thermal shock resistance against a sudden heat cycle, it is preferable to set the oxygen concentration gradient to 0.5 to 0.1% by weight / μm. If the oxygen concentration exceeds 25% or if the oxygen concentration gradient is greater than 1 wt% / μm, both SiC and S
This is because the difference in the coefficient of thermal expansion from iO 2 becomes too large, the strain inside the film is large, and the film itself may be cracked or damaged. Further, when the oxygen concentration is less than 5% by weight or the oxygen concentration gradient is less than 0.1% by weight / μm, which is too small, peeling easily occurs from the vicinity of the joint surface. The oxygen-containing SiC layer of the CVD-SiC coated member of the present invention has 2
It is formed with a thickness of 0 to 120 μm, and is usually about 60 μm.
【０００８】本発明において、酸素含有ＳｉＣ膜を基板
に被覆するＣＶＤ法は、従来のＣＶＤ−ＳｉＣを形成す
る方法とほぼ同様にして行うことができ、ＳｉＣｌ4 等
のクロロシラン系ガス、メタン（ＣＨ4 ）、プロパン
（Ｃ3 Ｈ8 ）等の炭化水素及び水素からなる原料ガスと
共に、酸素ガス（Ｏ2 ）、または、酸素原子を含むガ
ス、例えば、一酸化炭素ガス（ＣＯ）を添加混入してＣ
ＶＤ処理域に流通して行うことができる。また、本発明
のＣＶＤ−ＳｉＣ被覆部材において、被覆膜である酸素
含有ＳｉＣ層は、表面から基材方向に酸素含有量が増加
して酸素濃度に勾配を有するようにするため、原料ガス
中に添加する酸素または酸素原子を含むガスの配合量
は、基材表面でのＣＶＤ膜形成から次第に減少させ、最
終的にはゼロとして、外表面層のＣＶＤ膜がＳｉＣ単層
となるように制御する。通常、原料ガス中の炭化水素と
酸素若しくは酸素を含むガスとを相対的に増減させ、例
えば、炭化水素ガス流量を標準状態で（以下同様）０．
２リットル／分から０．２５リットル／分に連続的に増
加すると共に、ＣＯガス流量を０．２リットル／分から
ゼロへ減少させる。また、基材表面へのＣＶＤ膜の形成
時における酸素を含むガスの配合量は、上記のように基
材の熱膨張係数値に応じて形成されるＣＶＤ膜中の酸素
濃度を２５重量％以下で変化させ、基材の熱膨張係数に
ほぼ合うように適宜選択することができる。例えば、ポ
リシリコンを基材として用いる場合は、単結晶シリコン
に比し熱膨張係数が大きく、ＣＯ等酸素含むガスの配合
量は少なくする。ＣＶＤ処理条件は、上記原料ガス組成
を変化させる以外は従来と同様にして行うことができ
る。通常、温度８００〜１３００℃、圧力３０〜７６０
Ｔｏｒｒで行うことができ、基板の種類によりその溶融
温度等に応じて適宜選択することができる。In the present invention, the CVD method for coating the oxygen-containing SiC film on the substrate can be carried out in substantially the same manner as the conventional method for forming CVD-SiC, and a chlorosilane-based gas such as SiCl 4 or methane (CH 3). 4 ), propane (C 3 H 8 ) and other raw material gas consisting of hydrocarbons and hydrogen, and oxygen gas (O 2 ) or a gas containing oxygen atoms, for example, carbon monoxide gas (CO) is added and mixed. C
It can be distributed to the VD processing area. In addition, in the CVD-SiC coated member of the present invention, the oxygen-containing SiC layer that is the coating film has a higher oxygen content in the direction from the surface to the base material so that the oxygen concentration has a gradient in the source gas. The amount of oxygen or a gas containing oxygen atoms added to is gradually decreased from the formation of the CVD film on the surface of the base material, and finally set to zero so that the CVD film of the outer surface layer is controlled to be a SiC single layer. To do. Usually, the hydrocarbons in the raw material gas and oxygen or a gas containing oxygen are relatively increased / decreased, and, for example, the hydrocarbon gas flow rate is set to 0.
The CO gas flow rate is reduced from 0.2 l / min to zero with a continuous increase from 2 l / min to 0.25 l / min. Further, the amount of the gas containing oxygen at the time of forming the CVD film on the surface of the base material is set such that the oxygen concentration in the CVD film formed according to the thermal expansion coefficient value of the base material is 25% by weight or less. And can be appropriately selected so as to approximately match the coefficient of thermal expansion of the substrate. For example, when polysilicon is used as the base material, the coefficient of thermal expansion is larger than that of single crystal silicon, and the amount of a gas containing oxygen such as CO is reduced. The CVD treatment conditions can be the same as the conventional one except that the composition of the raw material gas is changed. Usually, temperature is 800-1300 ° C, pressure is 30-760
It can be performed at Torr, and can be appropriately selected according to the melting temperature and the like depending on the type of the substrate.
【０００９】[0009]
【実施例】本発明について実施例に基づき、更に詳細に
説明する。但し、本発明は、下記の実施例に制限される
ものでない。 実施例１ 基材としての単結晶シリコン円盤（１５０ｍｍφ）を、
炉内で１３００℃に加熱し、原料ガスのＳｉＣｌ4 、Ｃ
Ｈ4 、Ｈ2 及びＣＯをそれぞれ標準状態で０．５０、
０．２、２．５及び０．３リットル／分で供給流通させ
た。総処理時間１２０分で単結晶シリコン基材上に６０
μｍの被膜を形成した。この間、ＳｉＣｌ4 及びＨ2 の
流量を一定に保持し、ＣＨ4 流量を０．２から０．３リ
ットル／分に増加させる一方、ＣＯ流量を０．３から
０．０リットル／分に減少させた。得られた単結晶シリ
コン上に形成されたＣＶＤ被覆された酸素含有ＳｉＣ膜
中の酸素濃度をＳＩＭＳ（二次イオン質量分析法）によ
り行った。その結果を図１に示した。図１において、横
軸は被覆膜厚さを示し、０μｍが膜表面に相当し、６０
μｍが膜と基材との接合部に相当する。図１により、酸
素濃度は、表面からの膜厚さ（表面層）が１０μｍを超
えると徐々に増加し、接合部まで（接合層）連続的に２
５％まで増加していることが分かる。この場合、膜中の
接合層の酸素濃度勾配は、０．５重量％／μｍであっ
た。なお、ＳＩＭＳによる酸素測定法においては、予め
酸素濃度を調整したＳｉＣ標準サンプルを準備し、Ｓｉ
Ｃ中のＳｉイオン強度と酸素イオン強度から、相対感度
係数（ＲＳＦ）ＣR を下式（１）により求め、得られた
ＲＳＦを基に下式（２）により試料中の酸素濃度ＤS を
算出した。このＳＩＭＳによる酸素濃度定量測定は、ｐ
ｐｍ以下の感度にて精度１０〜２０％程度で容易に行う
ことができる。但し、式中、ＤO は標準サンプルに注入
した酸素濃度（原子数／ｃｍ2 ）、Ｉr はマトリックス
（Ｓｉまたは炭素（Ｃ））の測定イオン強度、Ｉs は試
料中の酸素元素の測定イオン強度、ｄは測定深さ（ｃ
ｍ）、ｎは測定深さまでのデータ数をそれぞれ表す。 ＣR ＝ＤO ・Ｉr ・ｎ／ｄ・ΣＩs （１） ＤS ＝ＣR ・Ｉs ／Ｉr （２） 本実施例においては、酸素濃度１×１０15原子数／ｃｍ
2 に調整したＳｉＣ標準サンプルを準備し、パーキン・
エルマー・６６００・ＳＩＭＳを用い、一次イオン種Ｃ
s+ 、一次イオン加速電圧５ＫｅＶ、一次イオン電流５
００ｎＡ、ラスター領域２００×３１５（μｍ）、分析
領域９０×１４０（μｍ）の条件で測定した。EXAMPLES The present invention will be described in more detail based on examples. However, the present invention is not limited to the following examples. Example 1 A single crystal silicon disk (150 mmφ) as a base material was
It is heated to 1300 ° C in the furnace and the raw material gas is SiCl 4 , C
H 4 , H 2 and CO are 0.50 in the standard state,
It was supplied and distributed at 0.2, 2.5 and 0.3 l / min. 60 on single crystal silicon substrate with total processing time of 120 minutes
A μm film was formed. During this period, the flow rates of SiCl 4 and H 2 were kept constant, the CH 4 flow rate was increased from 0.2 to 0.3 liter / min, and the CO flow rate was reduced from 0.3 to 0.0 liter / min. It was The oxygen concentration in the obtained CVD-containing oxygen-containing SiC film formed on the obtained single crystal silicon was measured by SIMS (secondary ion mass spectrometry). The results are shown in Fig. 1. In FIG. 1, the horizontal axis represents the coating film thickness, and 0 μm corresponds to the film surface.
μm corresponds to the joint between the film and the base material. According to FIG. 1, the oxygen concentration gradually increases when the film thickness from the surface (surface layer) exceeds 10 μm, and continuously increases to 2 at the bonding portion (bonding layer).
It can be seen that it has increased to 5%. In this case, the oxygen concentration gradient of the bonding layer in the film was 0.5% by weight / μm. In the oxygen measurement method by SIMS, a SiC standard sample whose oxygen concentration is adjusted in advance is prepared.
The relative sensitivity coefficient (RSF) C R is calculated from the Si ion strength and oxygen ion strength in C by the following equation (1), and the oxygen concentration D S in the sample is calculated by the following equation (2) based on the obtained RSF. It was calculated. The oxygen concentration quantitative measurement by SIMS is p
It can be easily performed with a sensitivity of pm or less and an accuracy of about 10 to 20%. Here, in the formula, D O is the oxygen concentration (atoms / cm 2 ) injected into the standard sample, I r is the measured ionic strength of the matrix (Si or carbon (C)), and I s is the measurement of oxygen element in the sample. Ionic strength, d is measurement depth (c
m) and n respectively represent the number of data up to the measurement depth. C R = D O · I r · n / d · ΣI s (1) D S = CR · I s / I r (2) In this embodiment, the oxygen concentration is 1 × 10 15 atoms / cm 2.
Prepare a SiC standard sample adjusted to 2 and
Using Elmer 6600 SIMS, primary ion species C
s + , primary ion acceleration voltage 5 KeV, primary ion current 5
The measurement was performed under the conditions of 00 nA, raster area 200 × 315 (μm), and analysis area 90 × 140 (μm).
【００１０】実施例２〜４ 原料ガス中のＳｉＣｌ4 及びＨ2 の流量を一定に保持
し、ＣＨ4 流量を０．２から０．３リットル／分に増加
させると共に、ＣＯ流量を次のように変化させた。即
ち、ＣＯ流量を０．２から０．０リットル／分に（実施
例２）、０．０５から０．０リットル／分（実施例
３）、０．２から０．０リットル／分（実施例４）にそ
れぞれ減少させ、また実施例４では接合層の厚さを２５
μｍとして全体のＣＶＤ被覆ＳｉＣ膜厚を３５μｍとし
た以外は、実施例１と同様に単結晶シリコン上に酸素含
有ＳｉＣ膜をＣＶＤ被覆形成した。得られた各ＣＶＤ被
覆ＳｉＣ膜について実施例１と同様に酸素濃度分布をＳ
ＩＭＳで測定し、その表面層と接合面での濃度及び接合
層の酸素濃度勾配を表１に示した。なお、実施例１の結
果も表１に共に示した。Examples 2 to 4 The flow rates of SiCl 4 and H 2 in the source gas were kept constant, the CH 4 flow rate was increased from 0.2 to 0.3 liter / min, and the CO flow rate was as follows. Changed to. That is, the CO flow rate was changed from 0.2 to 0.0 liter / min (Example 2), 0.05 to 0.0 liter / min (Example 3), and 0.2 to 0.0 liter / min (Example). Example 4) respectively, and in Example 4 the thickness of the bonding layer was 25
The oxygen-containing SiC film was CVD-coated on the single crystal silicon in the same manner as in Example 1 except that the entire CVD-coated SiC film thickness was 35 μm. The oxygen concentration distribution of each of the obtained CVD-coated SiC films was changed to S in the same manner as in Example 1.
Table 1 shows the concentrations of the surface layer and the bonding surface, and the oxygen concentration gradient of the bonding layer, which were measured by IMS. The results of Example 1 are also shown in Table 1.
【００１１】比較例１〜５ ＣＶＤ条件を次のように変える以外は実施例１と同様に
してＣＶＤ被覆処理した。即ち、ＣＨ4 流量を０．０か
ら０．３リットル／分に増加し（比較例１）、膜厚を３
５μｍとし（比較例２）、ＣＯ流量を当初０．３５リッ
トル／分とし（比較例３）、ＣＯを全く配合することな
くＣＨ4 流量を０．３リットル／分としてそのまま変化
することなく維持し（比較例４：従来のＣＶＤ−ＳｉＣ
被覆法）、ＣＨ4 及びＣＯ流量をそのまま変化すること
なく維持して（比較例５）、それぞれＣＶＤ−ＳｉＣ膜
を被覆した。得られた各ＣＶＤ被覆膜中の酸素濃度を実
施例１と同様にＳＩＭＳで測定し、その表面層と接合面
での濃度及び酸素濃度勾配を表１に示した。Comparative Examples 1 to 5 CVD coating processing was performed in the same manner as in Example 1 except that the CVD conditions were changed as follows. That is, the CH 4 flow rate was increased from 0.0 to 0.3 liter / min (Comparative Example 1), and the film thickness was 3
5 μm (Comparative Example 2), CO flow rate was initially 0.35 L / min (Comparative Example 3), CH 4 flow rate was 0.3 L / min without adding any CO and maintained unchanged. (Comparative Example 4: Conventional CVD-SiC
Coating method), the CH 4 and CO flow rates were maintained unchanged (Comparative Example 5), and the CVD-SiC films were coated respectively. The oxygen concentration in each obtained CVD coating film was measured by SIMS in the same manner as in Example 1, and the concentration and oxygen concentration gradient in the surface layer and the bonding surface are shown in Table 1.
【００１２】[0012]
【表１】 尚、◎、○、△は耐用回数を示し、◎＞○＞△である。[Table 1] In addition, ⊚, ◯, and Δ indicate the number of times of service, and ⊚>∘> Δ.
【００１３】評価１（不純物拡散防止効果の評価） 上記実施例１〜４及び比較例１〜５で得られた各ＣＶＤ
−ＳｉＣ膜被覆の単結晶シリコン円盤上に、ウエハを載
置し酸化雰囲気炉内で１０００℃で１０時間熱処理し
た。その結果、ウエハ表面に形成された酸化膜中に取り
込まれた不純物Ｎａ、Ａｌ、Ｆｅ及びＣｕの各含有量
（原子数／ｃｍ2 ）レベルを測定した。その結果を表１
に示した。Evaluation 1 (Evaluation of Effect of Impurity Diffusion Prevention) Each of the CVDs obtained in Examples 1 to 4 and Comparative Examples 1 to 5 above.
A wafer was placed on a single crystal silicon disk coated with a SiC film and heat-treated at 1000 ° C. for 10 hours in an oxidizing atmosphere furnace. As a result, the levels of each of the impurities Na, Al, Fe, and Cu (atoms / cm 2 ) incorporated in the oxide film formed on the wafer surface were measured. The results are shown in Table 1.
It was shown to.
【００１４】評価２及び３（被膜と基材との密着性評
価） 上記実施例１〜４及び比較例１〜５で得られた各ＣＶＤ
−ＳｉＣ膜被覆の単結晶シリコン円盤をヒートサイクル
試験した。ヒートサイクル試験は、１２００℃の炉内に
１０分間保持し、炉外に出して１０分間保持し、再び炉
内に入れるサイクルを炉内外への搬出入速度２００ｍｍ
／分で１０００回繰り返し行った。その結果、本発明の
表面から接合面に増加する濃度勾配を有して所定の酸素
量を含有するＣＶＤ−ＳｉＣ膜が被覆された単結晶シリ
コン円盤部材は、表面が酸化膜が形成された以外は以上
がなく、膜の剥離もなく良好であった。一方、比較例で
得られ接合層で酸素濃度勾配を有さないものは、剥離や
亀裂が発生した。また、実施例１〜４で得られた各ＣＶ
Ｄ−ＳｉＣ膜被覆の単結晶シリコン円盤について水冷ヒ
ートサイクル試験を行った。水冷ヒートサイクル試験
は、上記ヒートサイクルにおいて、１２００℃の炉内に
１０分間保持した後、２０℃の水中に投入し、再び炉内
に入れるサイクルを炉内、水中への搬出入速度２００ｍ
ｍ／分で繰り返し行い、その耐用回数を測定し、その結
果を表１に示した。なお、比較例１〜４で得られたＣＶ
Ｄ−ＳｉＣ膜被覆単結晶シリコン円盤部材は、ヒートサ
イクル試験で膜剥離や亀裂が生じ、水冷ヒートサイクル
試験は行わなかった。また、比較例５のものは、ヒート
サイクルで亀裂や剥離は生じないが、表面層に酸素が含
有されるため半導体プロセス用部材としては適さない。
即ち、例えば、半導体製造用のボートとして用いる場
合、熱処理では酸化膜、ＬＰＣＶＤ処理ではＣＶＤ膜が
付着するため、使用後ボート表面は、通常、ＨＦやＨＦ
−ＨＮＯ3 による酸洗浄が行われる。比較例５の部材の
表面層には、酸素の存在によりＳｉＯ2 が形成されてお
り、そのＳｉＯ2 が酸洗浄において溶出し部材表面が次
第に劣化されパーティクル発生の原因となり、半導体を
汚染するため使用することができない。Evaluations 2 and 3 (Evaluation of Adhesion between Coating and Substrate) Each CVD obtained in the above Examples 1 to 4 and Comparative Examples 1 to 5
The SiC film-coated single crystal silicon disks were heat cycle tested. In the heat cycle test, a cycle of holding in a furnace at 1200 ° C. for 10 minutes, taking out of the furnace and holding for 10 minutes, and then putting it in the furnace again was carried out at an in / out speed of 200 mm.
Repeated 1000 times / min. As a result, the single-crystal silicon disc member of the present invention, which is covered with the CVD-SiC film having a concentration gradient increasing from the surface to the bonding surface and containing a predetermined amount of oxygen, except that an oxide film is formed on the surface. There was no above, and the film was good without peeling. On the other hand, in the joining layer obtained in the comparative example and having no oxygen concentration gradient, peeling or cracking occurred. Moreover, each CV obtained in Examples 1 to 4
A water-cooled heat cycle test was conducted on the single crystal silicon disk coated with the D-SiC film. In the water cooling heat cycle test, in the above heat cycle, after holding in a 1200 ° C. furnace for 10 minutes, it is put in 20 ° C. water and then put in the furnace again.
Repeatedly at m / min, the number of times of service was measured, and the results are shown in Table 1. The CVs obtained in Comparative Examples 1 to 4
The D-SiC film-coated single crystal silicon disk member suffered film peeling and cracks in the heat cycle test, and was not subjected to the water cooling heat cycle test. Further, the sample of Comparative Example 5 is not suitable as a semiconductor process member because the surface layer contains oxygen although cracks and peeling do not occur in the heat cycle.
That is, for example, when used as a boat for semiconductor manufacturing, an oxide film is attached by heat treatment and a CVD film is attached by LPCVD treatment, so that the boat surface after use is usually HF or HF.
An acid wash with HNO 3 is performed. In the surface layer of the member of Comparative Example 5, SiO 2 was formed due to the presence of oxygen, and the SiO 2 was eluted during acid cleaning to gradually deteriorate the member surface and cause particles to be generated, which was used for contaminating the semiconductor. Can not do it.
【００１５】[0015]
【発明の効果】本発明のＣＶＤ−ＳｉＣ被覆部材は、Ｃ
ＶＤ−ＳｉＣ膜中に、基材方向に所定の増加する濃度勾
配で酸素を含有させ、その外表面は従来のＣＶＤ−Ｓｉ
Ｃ膜と同様に保持することにより、従来、熱膨張係数が
小さく、ＣＶＤ−ＳｉＣ被覆用基材としては適さないと
されていた高純度材のシリコン結晶体等を基材に用いる
ことができ、膜の剥離もなく、且つ、不純物の拡散を著
しく防止できる。そのため、半導体製造における熱処理
工程等で用いる各種部材として好適である。The CVD-SiC coated member of the present invention is C
Oxygen is contained in the VD-SiC film at a predetermined increasing concentration gradient in the direction of the substrate, and the outer surface thereof is formed by conventional CVD-Si.
By holding in the same manner as the C film, a high-purity material such as a silicon crystal body, which has been conventionally considered to have a small thermal expansion coefficient and is not suitable as a CVD-SiC coating base material, can be used as the base material. There is no peeling of the film, and the diffusion of impurities can be significantly prevented. Therefore, it is suitable as various members used in a heat treatment step or the like in semiconductor manufacturing.
【図１】本発明の一実施例のＣＶＤ法で形成した酸素含
有ＳｉＣ膜の厚さと酸素濃度との関係図である。FIG. 1 is a relationship diagram between the thickness and oxygen concentration of an oxygen-containing SiC film formed by a CVD method according to an embodiment of the present invention.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 市島 雅彦 山形県西置賜郡小国町大字小国町378 東 芝セラミックス株式会社小国製造所内 (72)発明者 佐藤 勝憲 山形県西置賜郡小国町大字小国町378 東 芝セラミックス株式会社小国製造所内 (72)発明者 伊藤 幸夫 山形県西置賜郡小国町大字小国町378 東 芝セラミックス株式会社小国製造所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiko Ichijima 378 Oguni-machi, Oguni-cho, Nishiokitama-gun, Yamagata Prefecture Inside the Oguni Factory of Toshiba Ceramics Co., Ltd. (72) Katsunori Sato 378 Oguni-machi, Oguni-cho, Nishiokitama-gun, Yamagata (72) Inventor Yukio Ito Oguni-machi, Nishikitama-gun, Yamagata Prefecture 378 Oguni-machi, Toshiba Ceramics Co., Ltd.
Claims (4)
有する基材表面をＣＶＤにより酸素含有ＳｉＣ膜で被覆
してなり、該酸素含有ＳｉＣ膜の酸素濃度が膜表面から
基材方向に連続的にまたは段階的に増加すると共に、表
面層で０．０５重量％以下で、且つ、該基材との接合面
層で２５重量％以下であることを特徴とするＣＶＤ−Ｓ
ｉＣ被覆部材。1. A substrate surface having a thermal expansion coefficient smaller than that of CVD-SiC is coated with an oxygen-containing SiC film by CVD, and the oxygen concentration of the oxygen-containing SiC film is continuous from the film surface toward the substrate. Alternatively, the CVD-S is characterized by gradually increasing and being 0.05% by weight or less in the surface layer and 25% by weight or less in the bonding surface layer with the base material.
iC coating member.
面層から膜厚方向に１重量％／μｍ以下の濃度勾配を有
する請求項１記載のＣＶＤ−ＳｉＣ被覆部材。2. The CVD-SiC coated member according to claim 1, wherein the contained oxygen concentration of the SiC film has a concentration gradient of 1% by weight / μm or less from the surface layer in the film thickness direction.
る請求項１または２記載のＣＶＤ−ＳｉＣ被覆部材。3. The CVD-SiC coated member according to claim 1, wherein the surface layer has a thickness of 10 μm or more.
項１、２または３記載のＣＶＤ−ＳｉＣ被覆部材。4. The CVD-SiC coated member according to claim 1, 2 or 3, wherein the base material is a silicon crystal body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14818795A JP3698372B2 (en) | 1995-05-23 | 1995-05-23 | CVD-SiC coated member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14818795A JP3698372B2 (en) | 1995-05-23 | 1995-05-23 | CVD-SiC coated member |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08319186A true JPH08319186A (en) | 1996-12-03 |
| JP3698372B2 JP3698372B2 (en) | 2005-09-21 |
Family
ID=15447195
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|---|---|---|---|
| JP14818795A Expired - Fee Related JP3698372B2 (en) | 1995-05-23 | 1995-05-23 | CVD-SiC coated member |
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| Country | Link |
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| JP2002222768A (en) * | 2001-01-24 | 2002-08-09 | Ibiden Co Ltd | Jig for semiconductor |
| JP2003045812A (en) * | 2001-07-31 | 2003-02-14 | Tokai Carbon Co Ltd | Component for apparatus for manufacturing silicon carbide semiconductor and method for manufacturing the same |
| US6737746B2 (en) | 2001-11-14 | 2004-05-18 | Renesas Technology Corp. | Semiconductor device containing copper diffusion preventive film of silicon carbide |
| JPWO2007139015A1 (en) * | 2006-05-31 | 2009-10-08 | コニカミノルタオプト株式会社 | Film forming method, mold and mold manufacturing method |
| JP2014114509A (en) * | 2012-12-06 | 2014-06-26 | Industry-Academic Cooperation Foundation Yonsei Univ | FORMATION METHOD AND DEVICE OF C/SiC INCLINATION COATING FILM |
| US9062370B2 (en) | 2009-04-02 | 2015-06-23 | Spawnt Private S.A.R.L. | Bodies coated by SiC and method for creating SiC-coated bodies |
-
1995
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Cited By (8)
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| JP2002222768A (en) * | 2001-01-24 | 2002-08-09 | Ibiden Co Ltd | Jig for semiconductor |
| JP2003045812A (en) * | 2001-07-31 | 2003-02-14 | Tokai Carbon Co Ltd | Component for apparatus for manufacturing silicon carbide semiconductor and method for manufacturing the same |
| JP4556090B2 (en) * | 2001-07-31 | 2010-10-06 | 東海カーボン株式会社 | Member for silicon carbide semiconductor manufacturing apparatus and method for manufacturing the same |
| US6737746B2 (en) | 2001-11-14 | 2004-05-18 | Renesas Technology Corp. | Semiconductor device containing copper diffusion preventive film of silicon carbide |
| JPWO2007139015A1 (en) * | 2006-05-31 | 2009-10-08 | コニカミノルタオプト株式会社 | Film forming method, mold and mold manufacturing method |
| US9062370B2 (en) | 2009-04-02 | 2015-06-23 | Spawnt Private S.A.R.L. | Bodies coated by SiC and method for creating SiC-coated bodies |
| JP2014114509A (en) * | 2012-12-06 | 2014-06-26 | Industry-Academic Cooperation Foundation Yonsei Univ | FORMATION METHOD AND DEVICE OF C/SiC INCLINATION COATING FILM |
| KR101469713B1 (en) * | 2012-12-06 | 2014-12-05 | 연세대학교 산학협력단 | METHOD AND APPARATUS FOR FORMING C/SiC FUNCTIONALLY GRADED COATING |
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| Publication number | Publication date |
|---|---|
| JP3698372B2 (en) | 2005-09-21 |
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