JPS61236672A - Pyrolytic boron nitride coated products and manufacture - Google Patents
Pyrolytic boron nitride coated products and manufactureInfo
- Publication number
- JPS61236672A JPS61236672A JP7756485A JP7756485A JPS61236672A JP S61236672 A JPS61236672 A JP S61236672A JP 7756485 A JP7756485 A JP 7756485A JP 7756485 A JP7756485 A JP 7756485A JP S61236672 A JPS61236672 A JP S61236672A
- Authority
- JP
- Japan
- Prior art keywords
- pbn
- boron nitride
- carbon
- pyrolytic boron
- layer
- 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.)
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- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、熱分解窒化ホウ素(以下PBN という)
抜機物品、特に、基材にカーボンを用いた基材カーボン
とPBN被榎膚とが強固に封有したPBN被榎物品およ
びその製法時にGaASやInPなどの化合物手導体単
結晶育成用の谷梱治共およびその製造に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to pyrolytic boron nitride (hereinafter referred to as PBN).
Punched products, especially PBN-covered products in which carbon is used as the base material and the PBN-covered skin is tightly sealed, and valley packaging for growing single crystals of compound conductors such as GaAS and InP during the manufacturing process thereof. Regarding Jikyo and its manufacturing.
PBNは高純度、高品賀の留化ホウ素(BN)として、
半導体や特殊合金製造用のルツボなどに巾広(用いられ
ている材料である。PBN is a high purity boron distillate (BN) from Takashinaga.
It is a wide material used in crucibles for manufacturing semiconductors and special alloys.
たとえば、GaAsなどの化合物牛傳体*U晶の育成法
の−っである液体刺止ナヨクラルスギー法(以下LEC
法という)では、自立型P B Nるっばが現任産業界
で中広(用いられている他、特にIC基板川の半絶縁性
市品實化合物千専体単結晶を育成する際には、結晶中に
カーボンが混入すると、不純物カーボンが不純物準位を
形成し、結晶の電気特性を劣化させるので、単結晶訂成
炉で用いられる各槓カーボン部材の光面にPBN被榎を
施すことで育成結晶へのカーボンの混入を防止すること
が試みられている。For example, the liquid stabilization method (hereinafter referred to as LEC) is a method for growing compound crystals such as GaAs.
In addition to being used in the current industry, free-standing PBN rubber is currently used in the industry, especially when growing semi-insulating commercial compound single crystals for IC substrates. When carbon is mixed into the crystal, the impurity carbon forms an impurity level and deteriorates the electrical properties of the crystal. Therefore, it is necessary to apply PBN coating to the optical surface of each carbon member used in a single crystal refining furnace. Attempts have been made to prevent the incorporation of carbon into grown crystals.
自立型PBNおよびPBN被ai?1品は、たとえば米
国特許第3,152.006号明細豊において開示され
ているように、三塩化ホウ素(B(2g)のようなハロ
ゲン化ホウ累とアンモニアを気体状原料とし、温度14
50〜2300℃、圧力5 Q Torr未滴の条件下
、カーボンなどの適当な基材表凹上にBNを析出させる
いわゆる化学気相蒸着法(以下CVD法という)により
製造され、CVDを施した彼、基材を除去すれが自立型
のPBN層品が、また基材をそのまま残せばPBN被覆
物品が得られるO
ところが、このようにして従来の技術に従って得たPB
N 被覆物品を、化合物半噂体単結晶胃成炉内も柵治
具のように加熱・冷却が繰り返えされる条件下で用いる
と、わずか数回、はなはだしい場合には第一回目の加熱
・冷却サイクルでPBN i&111にクラックが入っ
たり、あるいはPBN被機増が基材から剥離・脱落した
りして使用不能になることがあり、そのイW頼性は着し
い低いという欠陥があった。特に、化合物半導体率結晶
有取炉のカーボン部品にPBN被覆を施したものを用い
る場合、PBN層に発生するクラックが微少であると、
目視ではクラックの発生に気付かず、そのためこの微少
クラックからカーボン不純物がwg結晶中に混入するが
、このような不具合は結晶育成中や、結晶取出し時には
検知されず、擾い工程を通って加工されたウェハーの電
気特性を6(1f定したり、あるいは更にIC化された
後の製品の特性、そのバラツキなどを測足したりして初
めて判明するため、多大の原材料、労力が無駄になると
いう問題があった。Freestanding PBN and PBN covered AI? One product, as disclosed in U.S. Pat. No. 3,152.006, for example, uses a boron halide such as boron trichloride (B (2 g)) and ammonia as gaseous raw materials and is heated at a temperature of 14
Manufactured by the so-called chemical vapor deposition method (hereinafter referred to as CVD method) in which BN is deposited on the surface of an appropriate base material such as carbon under conditions of 50 to 2300 ° C. and a pressure of 5 Q Torr with no drops. However, if the base material is removed, a self-supporting PBN layered product can be obtained, and if the base material is left as is, a PBN coated article can be obtained.
N If the coated article is used under conditions in which heating and cooling are repeated in a single crystal gasification furnace for compound semicircular solids, like a fence jig, the heating and cooling may be repeated only a few times, or in extreme cases, the first heating and cooling may be repeated. During the cooling cycle, PBN i&111 may crack or the PBN cover may peel off or fall off from the base material, making it unusable, and its reliability is extremely low. In particular, when using PBN-coated carbon parts for compound semiconductor crystal furnaces, if the cracks that occur in the PBN layer are minute,
The occurrence of cracks is not noticed visually, and therefore carbon impurities are mixed into the WG crystal through these minute cracks, but such defects are not detected during crystal growth or when taking out the crystal, and are processed through the grinding process. The problem is that a large amount of raw materials and labor are wasted because the electrical characteristics of the wafer cannot be determined until the electrical characteristics of the wafer are determined, or the characteristics of the product after it has been made into an IC, and its variations are determined. was there.
本発明省らは上a己の欠点を解消するためにいろいろ研
究ヲ重ねたところ、付着力にすぐれ、加熱・冷却を繰り
返しても剥がれにくいPBN層で被覆された物品を得る
には、特にその基材(カーボン)の密度と、PBN層の
析出温度、そしてPBN層の厚さを、特定の範囲にする
必要があることを見出し、本発明に到達したものである
。The Ministry of the Invention and others have conducted various studies to overcome the shortcomings of the above, and have found that in order to obtain an article coated with a PBN layer that has excellent adhesion and is difficult to peel off even after repeated heating and cooling, The present invention was achieved by discovering that the density of the base material (carbon), the precipitation temperature of the PBN layer, and the thickness of the PBN layer need to be within specific ranges.
本発明の第1発明は、ノ・ロゲン化ホウ累ガスとアンモ
ニアガスを原料とする化学″気相熱分解法より、基材カ
ーボン表面上にPBNを析出・被覆してなる熱分解窒化
ホウ素抜榎物品であって、しかも
(+)基材カーボンの見掛比重が1.95〜−以下で、
かつ
(II) P B N被覆層が温度1500〜1920
℃で析出されたものであって、しかも ゛
(III) P B N被覆層の厚さが10μm〜3−
であることを特徴とするPB’N被榎物品であり、また
第2発明はハロゲン化ホウ素ガスとアンモニアガスを原
料とするCVD法により基材カーボン表面にPBN被覆
層を形成させる際に、50Torrσ〕圧力下において
、
見掛比重が1.95f/CI4以下の所望形状の基材カ
ーボンを用い、圧力0.5〜50 TorrS温度の条
件下、PBNを析出させ、その被覆層の厚さを10μm
〜3鰭とする
ことを特徴とするPBN被覆物品の製法である。The first invention of the present invention is a pyrolytic boron nitride dehydrogenation method in which PBN is deposited and coated on the surface of a base carbon by a chemical vapor phase pyrolysis method using a borogenide gas and ammonia gas as raw materials. An Enoki article, in which the apparent specific gravity of the (+) base carbon is 1.95 to - or less,
and (II) the PBN coating layer has a temperature of 1500 to 1920
℃, and the thickness of the ゛(III) PBN coating layer is 10 μm to 3-
The second invention is a PB'N coated article characterized in that when a PBN coating layer is formed on the surface of the base carbon by a CVD method using boron halide gas and ammonia gas as raw materials, 50 Torrσ ] Under pressure, PBN is precipitated at a pressure of 0.5 to 50 TorrS using a base carbon having a desired shape with an apparent specific gravity of 1.95 f/CI4 or less, and the thickness of the coating layer is 10 μm.
This is a method for producing a PBN-coated article characterized by having ~3 fins.
以下、さらに本発明を畦しく説明する。The present invention will be explained in more detail below.
本発明において、基材カーボンはその見掛比重が1.9
5 t/−以下のものでなければならない。In the present invention, the base carbon has an apparent specific gravity of 1.9.
It must be less than 5t/-.
その理由は、見掛比重が1.95t/cdを越えるカー
ボンを基材として用いると、次に説明する析出温度をど
のように選んでも、PBN層の“カーボン基材への付着
力が不足し□、本発明の目的であるPBNI−の付着力
がすぐれたPBN被S物品が得られないからである。尚
、基材カーボンの見掛比重が1.95f/d以下とそれ
を越えた場合にPBN層の付着力に差が生ずる原因は、
基材カーボンの表向気孔部でのアンカー効果の差による
も力と考えられる。The reason for this is that if carbon with an apparent specific gravity exceeding 1.95 t/cd is used as a base material, the adhesion of the PBN layer to the carbon base material will be insufficient, no matter how you choose the precipitation temperature described below. □This is because it is not possible to obtain a PBN S article with excellent PBNI adhesion, which is the object of the present invention.In addition, when the apparent specific gravity of the base carbon is 1.95 f/d or less and exceeds it, The reason why there is a difference in the adhesion strength of the PBN layer is as follows.
The force is also thought to be due to the difference in anchoring effect in the surface pores of the base carbon.
PBN被覆層の析出温度を1500〜1920℃に限定
したのは、被積層の強度と基材への付着力とを好適なも
のとするためである。部ち、析出温度が1500℃未満
であると生成するPBN層の結晶性が低く、被&層自身
の強度が低いものとなり、加熱、冷却の繰り返しにより
発生する応力によって′4fi&鳩にクランクを生じや
ずくなるからである。また析出温度が1920℃を越え
ると、基材カーボンと被損PBN層の界面でわずかなが
らB4Cの生成が起きるためと思われるが、カーボンと
PBN界面の付着力が急激に低下し又PBN層がカーボ
ン基月から剥がれやすくなる。The reason why the precipitation temperature of the PBN coating layer is limited to 1500 to 1920°C is to optimize the strength of the layer to be laminated and the adhesion to the base material. On the other hand, if the precipitation temperature is less than 1500℃, the crystallinity of the PBN layer formed will be low, and the strength of the coated layer itself will be low, and the stress generated by repeated heating and cooling will cause cracks in the PBN layer. This is because it becomes dark. Furthermore, when the precipitation temperature exceeds 1920°C, the adhesion force between the carbon and PBN interface decreases rapidly and the PBN layer is It becomes easy to peel off from the carbon base.
このようなことから、PBN被a鳩を析出させる温度は
1500−1920℃でなけれはならないが、PBN層
の強度を向く、しかも付層力を籏同かつ安定して得るに
は特に1600〜1900℃の温度で析出させることが
重要である。For this reason, the temperature at which the PBN layer is precipitated must be 1500-1920°C, but in order to increase the strength of the PBN layer and to obtain the same and stable layering force, it is especially necessary to set the temperature at 1600-1920°C. It is important to precipitate at a temperature of °C.
PBN被積層の厚さは10μm〜3111I+でなけれ
はならない。厚さが10μm未満であると被積層の厚さ
が薄いために基材カーボンがPBN被榎被積拡散して外
部に逃散してしまい、PBN被模の効果が十分に得られ
ず、また厚さが3霧を越えると、PBN被a層中の残留
応力が増大してP B N 11の自然剥離が起ぎゃす
(なるからである。後者の現象は、析出したPBN層の
厚さが後に機械的に研削してPBN層の厚さを3W!a
以下にしても、残留応力は太き(、仇って不発ψ」の物
品の製造においては、析出膜厚が3鰭以下となるように
PBNI−の析出栄汗と析出副産を定めなければならな
い。The thickness of the PBN overlay must be between 10 μm and 3111I+. If the thickness is less than 10 μm, the thickness of the layer to be laminated is so thin that the base carbon will diffuse into the PBN layer and escape to the outside, and the effect of the PBN layer will not be sufficiently obtained. When the thickness exceeds 3, the residual stress in the PBN a-layer increases and spontaneous peeling of PBN 11 occurs.The latter phenomenon occurs when the thickness of the precipitated PBN layer increases. Later, the thickness of the PBN layer was reduced to 3W!a by mechanical grinding.
Even if the residual stress is large (and therefore non-explosion ψ), in the manufacture of products, the precipitation and precipitation by-products of PBNI must be determined so that the thickness of the deposited film is 3 fins or less. It won't happen.
本発明の製法によるPBN級後物品は、PBN層の基材
カーボンへの付層力が鍾(、しかもPBN層の強度も高
いので、高崗においてもカーボンが蒸発することがなく
、また加熱・冷却を繰り返してもPBN被機]曽にクラ
ック、坊1岨・脱溶を生じないという%徴を有するもの
である。The PBN-grade product produced by the manufacturing method of the present invention has a high adhesion force of the PBN layer to the base carbon, and the strength of the PBN layer is also high, so the carbon does not evaporate even when heated, and Even after repeated cooling, the PBN material does not exhibit any cracks, cracks or dissolution.
実施例1゜
内径10crn%長さ40mの黒鉛製円筒型反応管な、
抵抗加熱式の身空加熱炉内に設け、反応管の一方には2
本のPBNNガス導入管を接続し、各々ガス状のBCl
2とNH3とを流した。ル応管内に天きさ0.5 am
X 5 cm X 5 cmの様々な見州比車の黒鉛
基材を置き、2 Torrの圧力下、1450〜196
0℃の様々の温度で黒鉛基材上にPBNを100μm/
時間の蒸層速度で0.5朝の厚さまで析出させて、PB
N被櫟黒鉛板試利試別た。このようにして得た試料ば、
先ずPBN被S層の状態を調べた後、蒙累逐囲気中で温
度1400℃に加熱した佐、呈龜まで冷却するテストを
繰り返し、毎圓の試料の状態を調べた。その結果を表1
に示す。Example 1 A graphite cylindrical reaction tube with an inner diameter of 10 crn% and a length of 40 m.
It is installed in a resistance heating type hollow heating furnace, and one side of the reaction tube has two
Connect two PBNN gas inlet tubes, each with gaseous BCl
2 and NH3 were flowed. The height in the reactor tube is 0.5 am.
A graphite substrate of various sizes of X 5 cm X 5 cm was placed and heated at 1450 to 196 mm under a pressure of 2 Torr.
100μm/100μm of PBN on graphite substrate at various temperatures of 0°C.
PB was deposited to a thickness of 0.5 hr at a evaporation rate of 0.5 hr.
Testing of graphite plate under N condition was carried out. The sample obtained in this way is
First, the state of the PBN S-covered layer was investigated, and then tests were repeated in which the sample was heated to a temperature of 1400° C. in an ambient atmosphere and then cooled to a temperature of 1,400° C., and the state of each sample was investigated. Table 1 shows the results.
Shown below.
(ハ)実験Nα1〜5は実施例、実験m4〜6は比較例
である。(c) Experiments Nα1 to Nα5 are examples, and experiments m4 to m6 are comparative examples.
実施例2゜
析出時間以外は実施例1の実験随2と同一の条件で、P
BN層の厚さを保々に変えたPBN被櫟被鉛黒鉛板試料
裂した。各試料を1w1JK窒炉内にセットし、10°
’ Torr負空下、崗度1600℃で5時間加熱し
、真空熱処理前後での重量変化を測定した。その結果を
衣2に示す。Example 2゜P under the same conditions as Experiment 2 of Example 1 except for the precipitation time.
PBN and lead-covered graphite plates with varying thicknesses of the BN layer were cracked. Set each sample in a 1w1JK nitrogen furnace and
' It was heated in a negative Torr atmosphere at a gravitas of 1600° C. for 5 hours, and the weight change before and after the vacuum heat treatment was measured. The results are shown in Figure 2.
衣 2
■ 実験N[L7〜8は実施例、実験随9〜10は比較
例である。Cloth 2 ■ Experiment N [L7-8 are examples, Experiments 9-10 are comparative examples.
上記実施例からも明らかなように、本発明のPBN物品
は、PBN被榎I−の強度が畠(、しかも基材カーボン
への付着力が強いので、繰り返しの加熱・冷却によって
もPBNI&al/−にクラックが発′生したり、ある
いはPBNa機層が剥離・脱落したりすることがな(、
長期にわたって熱サイクル下で安定して用いることがで
きる。特に化合物半導体単結晶育成炉のカーボンヒータ
ーやサセプターに本発明のPBN被榎を施した部品を用
いると、PBNl157−がカーボンの蒸発を防止する
ので育成単結晶の電気時性が低下することな(、しかも
畏期にわたり繰り返し便用することができるという効果
が得られる。As is clear from the above examples, in the PBN article of the present invention, the strength of the PBN I- is high (and the adhesion to the base carbon is strong), so even after repeated heating and cooling, the PBNI&al/- There will be no cracking or peeling or falling off of the PBNa layer (
It can be stably used over long periods of time under thermal cycles. In particular, when the PBN-coated parts of the present invention are used in the carbon heater or susceptor of a compound semiconductor single crystal growth furnace, the electrochronicity of the grown single crystal will not deteriorate because PBN157- prevents carbon evaporation ( Moreover, it has the effect of being able to be used repeatedly over a period of time.
Claims (2)
とする化学気相熱分解法により基材カーボン表面上に窒
化ホウ素を被覆してなる熱分解窒化ホウ素被覆物品であ
つて、しかもその基材カーボンの見掛比重が1.95g
/cm^3以下で、かつ熱分解窒化ホウ素被覆層が温度
1500〜1920℃で析出されたもので、その熱分解
窒化ホウ素被覆層の厚さが10μm〜3mmであること
を特徴とする熱分解窒化ホウ素被覆物品。(1) A pyrolytic boron nitride-coated article obtained by coating the surface of a base carbon with boron nitride by a chemical vapor phase pyrolysis method using boron halide gas and ammonia gas as raw materials, and the base carbon The apparent specific gravity of
/cm^3 or less, and the pyrolytic boron nitride coating layer is deposited at a temperature of 1500 to 1920°C, and the pyrolytic boron nitride coating layer has a thickness of 10 μm to 3 mm. Boron nitride coated articles.
とする化学気相熱分解法により基材カーボン表面に熱分
解窒化ホウ素被覆層を形成させる際に、見掛比重が1.
95g/cm^3以下の所望形状のカーボン基材を用い
、圧力0.5〜50Torr、温度1500〜1920
℃の条件下、(a)熱分解窒化ホウ素を析出被覆させ、
その被覆層の厚さを10μm〜3mmとする ことを特徴とする熱分解ホウ素被覆物品の製法。(2) When a pyrolytic boron nitride coating layer is formed on the surface of the base carbon by a chemical vapor phase pyrolysis method using boron halide gas and ammonia gas as raw materials, an apparent specific gravity of 1.
Using a carbon base material with a desired shape of 95 g/cm^3 or less, pressure 0.5 to 50 Torr, temperature 1500 to 1920
℃ conditions, (a) depositing pyrolytic boron nitride;
A method for producing a pyrolytic boron coated article, characterized in that the thickness of the coating layer is 10 μm to 3 mm.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7756485A JPS61236672A (en) | 1985-04-13 | 1985-04-13 | Pyrolytic boron nitride coated products and manufacture |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7756485A JPS61236672A (en) | 1985-04-13 | 1985-04-13 | Pyrolytic boron nitride coated products and manufacture |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS61236672A true JPS61236672A (en) | 1986-10-21 |
Family
ID=13637505
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP7756485A Pending JPS61236672A (en) | 1985-04-13 | 1985-04-13 | Pyrolytic boron nitride coated products and manufacture |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS61236672A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1990004574A1 (en) * | 1988-10-21 | 1990-05-03 | Kawasaki Steel Corporation | Composite boron nitride material and process for its production |
JPH0316994A (en) * | 1989-06-12 | 1991-01-24 | Nippon Mining Co Ltd | Growth of compound semiconductor single crystal |
WO1995014645A1 (en) * | 1993-11-26 | 1995-06-01 | Commissariat A L'energie Atomique | Method for densifying a porous structure using boron nitride, and porous structure densified with boron nitride |
JP2011507795A (en) * | 2007-12-31 | 2011-03-10 | モーメンティブ パフォーマンス マテリアルズ インコーポレイテッド | Low thermal conductivity low density pyrolytic boron nitride material, manufacturing method and article manufactured therefrom |
JP2015074573A (en) * | 2013-10-08 | 2015-04-20 | 株式会社村田製作所 | Sagger for firing and method for producing electronic component |
-
1985
- 1985-04-13 JP JP7756485A patent/JPS61236672A/en active Pending
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1990004574A1 (en) * | 1988-10-21 | 1990-05-03 | Kawasaki Steel Corporation | Composite boron nitride material and process for its production |
JPH0316994A (en) * | 1989-06-12 | 1991-01-24 | Nippon Mining Co Ltd | Growth of compound semiconductor single crystal |
WO1995014645A1 (en) * | 1993-11-26 | 1995-06-01 | Commissariat A L'energie Atomique | Method for densifying a porous structure using boron nitride, and porous structure densified with boron nitride |
FR2712884A1 (en) * | 1993-11-26 | 1995-06-02 | Commissariat Energie Atomique | Process for densifying a porous structure with boron nitride and porous structure densified with boron nitride |
JP2011507795A (en) * | 2007-12-31 | 2011-03-10 | モーメンティブ パフォーマンス マテリアルズ インコーポレイテッド | Low thermal conductivity low density pyrolytic boron nitride material, manufacturing method and article manufactured therefrom |
JP2015074573A (en) * | 2013-10-08 | 2015-04-20 | 株式会社村田製作所 | Sagger for firing and method for producing electronic component |
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