JPS6298610A - Substrate heating mechanism for crystal growth - Google Patents

Abstract

PURPOSE:To enable the titled substrate heating mechanism to accomplish an excellent temperature distribution on the surface of a growing substrate irrespective of the size of the growing substrate by a method wherein a heat generating body is divided into two or more independent zones, and the temperature of each zone is controlled independently. CONSTITUTION:A heat generating body susceptor 21 consists of a PBN disc, a Ta heat generating body 22 is wound inside and another Ta heat generating body 23 is wound outside independently, they are constructed in such a manner that their temperature is controlled independently. A heat diffusing plate 28 is formed by applying PBN 30, for example, on one half of a carbon plate 29, and said heat diffusing plate 28 performs an additional function as a press- plate to be used for fixing of the heat generating bodies 22 and 23. Moreover, a substrate 32 is formed in such a manner that it can be rotated together with an Mo susceptor 33 in the direction as shown by the arrow 37 in the diagram, and a heat equalizing property an the uniformity in thickness of film when it is formed and the distribution of composition can be secured. Thus, heaters are divided into two zones, their temperature can be controlled separately, and an arbitrary temperature distribution can be accomplished on the plane.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、分子線結晶成長に係り、特に■ｎンルダを用
いない、所謂子Ｉｎレス方式の結晶成長基板の均一な面
内温度分布を実現するに好適な、基板加熱ヒータに関す
る。[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to molecular beam crystal growth, and in particular realizes uniform in-plane temperature distribution of a crystal growth substrate using the so-called In-less method, which does not use n-irradiation. The present invention relates to a substrate heater suitable for heating a substrate.

〔発明の背景〕[Background of the invention]

従来の基板加熱用　−夕の構造は、第１図に示す様に、
Ｔａ、Ｗなどを発熱体１１として用いる。The structure of the conventional substrate heating device is as shown in Figure 1.
Ta, W, or the like is used as the heating element 11.

該発熱体は通常１本のワイヤまたは、リボンで作られて
おり、ヒータ構成としては１グーンとなっている。この
様な１ゾーン惧成のヒータを工ｎレス基板の加熱に用い
る場合、該発熱体と基板１３の間に熱拡散板１２を挿入
し、基板１３０面内温度分布が均一なる様にしているが
実際には、その値は±３〜５°Ｃともめる。発明者らは
、先に熱拡散板に、熱的良導体を、畦気的不導体でくる
んだものを使用した、■ｎレス用ヒータ構造を提案し、
２インチＧａＡＳウェハにおける面内の温度分布を±１
℃まで向上した。しかし、ウェハーサイズが３インチの
場合は、基板面内の温度分布が±２　’Ｃと太きくなっ
てしまった。The heating element is usually made of a single wire or ribbon, and has a single heater configuration. When such a one-zone heater is used to heat a non-contact board, a heat diffusion plate 12 is inserted between the heating element and the board 13 to make the temperature distribution within the plane of the board 130 uniform. However, in reality, the value is estimated to be ±3 to 5°C. The inventors previously proposed a heater structure for nless using a heat diffusion plate wrapped with a thermally good conductor wrapped in a ribbed nonconductor.
In-plane temperature distribution of 2-inch GaAS wafer ±1
It improved to ℃. However, when the wafer size was 3 inches, the temperature distribution within the substrate surface was as wide as ±2'C.

基板加熱方法の従来技術としては、特開昭６０−８１８
２０号公報に記載のものがある。As a conventional technique of substrate heating method, Japanese Patent Application Laid-Open No. 60-818
There is one described in Publication No. 20.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、成長基板のサイズに関係なく艮好な成
長基板面内１品度分布を実現し得る、成長基板加熱装置
を提供することＫある。An object of the present invention is to provide a growth substrate heating device that can realize a good quality distribution within the growth substrate surface regardless of the size of the growth substrate.

〔発明の概要〕[Summary of the invention]

成長基板の加熱において、均一な温度分布を得る上で最
も問題となるのはウエノ・面内での熱拡散の状態が異な
ることである。特にエッヂ部分から熱拡散は大きく、ウ
エノ・−周辺部では、例えヒーターからの加熱が一様で
あったとしても、ウエノ・中央部に比較し温度が低くな
る。この様な問題を解決するには基板ウエノ・−加熱用
のヒータの温度分布を任意に設定し得る構造とする必要
がある。When heating a growth substrate, the biggest problem in obtaining a uniform temperature distribution is the difference in the state of thermal diffusion within the surface of the substrate. In particular, heat diffusion is large from the edge portions, and even if the heating from the heater is uniform, the temperature at the periphery will be lower than that at the center. To solve such problems, it is necessary to have a structure in which the temperature distribution of the heater for heating the substrate can be arbitrarily set.

即ち多ゾーンの発熱体構成とし、各々のヒータの温度を
外部より任意に設定し得る様にしなければならない。That is, a multi-zone heating element configuration must be used, and the temperature of each heater must be set arbitrarily from the outside.

〔発明の実施例〕[Embodiments of the invention]

以下本発明を実施例に基づき詳細に説明する。 The present invention will be described in detail below based on examples.

実施例１ 第２図は、本発明の成長基板加熱機構に、被加熱ＧａＡ
Ｓウエノ・を取付だ状態を示す側断面図である。図中２
１は、ＰＢＮの円板で出来た発熱体サセプター、２２，
２３は’ｒａｎ発熱体であり、２２は内１１１１１に、
２３は外側に各々独立して巻いてあり、各々独立に温度
コントロール出来る構造となっている。２４は、内側の
発熱体の電流導入線、２５は外側の発熱体の′−電流導
入線あり、２６．２７は、各々の発熱体の測温のための
熱電対である。Example 1 FIG. 2 shows a growth substrate heating mechanism of the present invention in which a heated GaA
It is a sectional side view showing a state in which S-Ueno is installed. 2 in the diagram
1 is a heating element susceptor made of a PBN disc; 22;
23 is the 'ran heating element, 22 is inside 11111,
23 are wound independently on the outside, and have a structure in which the temperature of each can be controlled independently. 24 is a current lead-in line for the inner heating element, 25 is a current lead-in line for the outer heating element, and 26 and 27 are thermocouples for measuring the temperature of each heating element.

２８は、熱拡散板であり、カーボン板２９０半分を例え
ばＰＢＮ３０でコーティングしたものであり、発熱体２
２．２３の固定用押え板を兼ねている。３１は効率的な
加熱を実現するためのＴａ製熱遮ヘイ板、３２は被加熱
用基板ウニ／・−であり、０．２覇厚さのｈｊ　Ｏで作
ったサセプタ３３に取シ付は加熱される。該サセプター
はｈｔ　ｏ裂のサセプタ取付ロッド３４に、スプリング
３５、押えリング３６で固定して取つけられている。な
お該基板３２ば、ＭＯサセプタ３３と共に例えば３７の
矢印の方向に回転できる球になっており、均熱性と成長
時の暎厚、組成の分布を均一性を確保している。28 is a heat diffusion plate, which is a half of the carbon plate 290 coated with PBN30, for example, and the heating element 2
2. It also serves as a holding plate for fixing 23. 31 is a heat shield plate made of Ta to realize efficient heating, 32 is a substrate to be heated, and a susceptor 33 made of hj O with a thickness of 0.2 mm has a mounting plate. heated. The susceptor is fixedly attached to a susceptor attachment rod 34 with a spring 35 and a retaining ring 36. Note that the substrate 32 is a sphere that can rotate together with the MO susceptor 33, for example, in the direction of the arrow 37, and ensures uniformity in heat uniformity, thickness during growth, and composition distribution.

本加熱＋＆構の岐も大きな′＃徴は加熱ヒータが２つの
ゾーンに分れて各々別々に温度制（２）出来る点にあり
、柾板の温度分布を面内で実現出来ることである。第２
図の実施例では２ゾ一ン例を示したが、ゾーン叙は面積
の匍］約等がなければさらに多く出来ることほぎうまで
もない。A major feature of the main heating+& structure is that the heater is divided into two zones and the temperature can be controlled separately (2) in each zone, making it possible to realize the temperature distribution of a square board within the plane. Second
Although the illustrated embodiment shows a two-zone example, it goes without saying that even more zones can be created if there is no reduction in area.

本実施例の基板加熱機構を用い３インチ径ＧａＡＳ基板
を鉄層したＭＢＥ　（分子線結晶成長）においてその面
内分布を±１　”Ｃ以下にすることが出来た。Using the substrate heating mechanism of this embodiment, the in-plane distribution of MBE (molecular beam crystal growth) on a 3-inch diameter GaAS substrate with an iron layer could be reduced to ±1''C or less.

実施例２ 第３図は、より精密な温度分布を実現するだめの最も簡
単な構造のＭＢＥ用加熱加熱機構断面図で示したもので
ある。図中４１．４２は高純度ＰＢＮ、Ａム０５等で作
られた或気的絶縁板で、Ｔａワイヤ等でなる発熱体４３
，４４．４５のサセプター、である。４６は、旨純度、
高密度のカーボン板の被加熱基板に対する面を除いて、
高純度のＰ　Ｂ　Ｎ　、　ｋ４０ｓ　等で枝長じた発熱
体面定押え板兼熱拡散板、４９は効率的な加熱を行うだ
めの熱シールド板である。本加熱機構の特徴は発熱体を
上下２層に分けであることである。即ち、本実施例では
熱拡散板に接する測に、被加熱ウェハの全面をほぼ同じ
程度面積をカバする様に均一に巻いた均一発熱体を、該
均一発熱体がサセプタ４２に接する面の反対側の面に接
して各々独立した面内温度分布制御用発熱体４４．４５
から成っていることである。これらの発熱体入力は、発
熱４３．５０の端子から行いその温度は熱電対５０で測
定する。発熱体４４．４５も同僚に５１．５２が入力端
子５４．５５が測温用熱電対である。Embodiment 2 FIG. 3 is a sectional view of a heating mechanism for MBE, which has the simplest structure to achieve more precise temperature distribution. In the figure, 41 and 42 are air insulating plates made of high-purity PBN, Am 05, etc., and a heating element 43 made of Ta wire, etc.
, 44.45 susceptors. 46 is umami purity,
Except for the surface of the high-density carbon plate facing the heated substrate,
The heating element surface fixing plate and heat diffusion plate 49 is a heat shield plate for efficient heating, which is made of high-purity PBN, k40s, or the like. The feature of this heating mechanism is that the heating element is divided into two layers, upper and lower. That is, in this embodiment, in contact with the heat diffusion plate, a uniform heating element that is uniformly wound so as to cover almost the same area over the entire surface of the wafer to be heated is placed on the opposite side of the surface where the uniform heating element contacts the susceptor 42. In-plane temperature distribution control heating elements 44 and 45 that are independent of each other in contact with the side surfaces
It consists of These heating element inputs are made from the terminals of the heat generators 43 and 50, and their temperatures are measured with thermocouples 50. The heating elements 44, 45 and 51, 52 are input terminals 54, 55, which are temperature measuring thermocouples.

本実施例では示さなかったが実施２と同様に熱拡散板４
６に対向して成長基板ウェハが置かれることは勿調であ
る。本実施例の基板加熱機構を用いた場合の成長基板面
内の温度分布を±０，７℃まで向上することが出来た。Although not shown in this embodiment, the heat diffusion plate 4 is similar to Embodiment 2.
Of course, a growth substrate wafer is placed opposite 6. When the substrate heating mechanism of this example was used, the temperature distribution within the plane of the growth substrate could be improved to ±0.7°C.

なお本実施例では２層の例について述べたが３層以上の
構成も可能なことは言うまでもない。In this embodiment, an example of two layers has been described, but it goes without saying that a configuration of three or more layers is also possible.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、ＭＢＥ（分子線結晶成長）の成長基板
の温度分布を、多ゾーン分割独立させた発熱体からの発
熱量？変えることにより任意に変えることができるので
、該成長基板面内の温度分布を制御した形で均一に出来
るという効果がある。According to the present invention, the temperature distribution of the growth substrate for MBE (molecular beam crystal growth) is divided into multiple zones and the heat generated by the heating element is made independent. Since the temperature can be changed arbitrarily by changing the temperature, there is an effect that the temperature distribution within the plane of the growth substrate can be made uniform in a controlled manner.

このことは、ＩｎｘＧａ１−ｘＡ”＋　Ｉ”＋−８Ｇａ
ｘ　ＡＳｙ　Ｐｌ−Ｆ＋　ＩｎｘＡｔ１−ｘ　ＡＳ等に
の材料の様に格子定数の整合が基板温度に大きく影響さ
れる系の基板加熱方法としてはほぼ理相に近いものであ
り、従来困−視されて。This means that InxGa1-xA"+I"+-8Ga
x ASy Pl-F+ InxAt1-x This method is almost logical as a substrate heating method for systems where lattice constant matching is greatly affected by substrate temperature, such as materials such as AS, and has been considered difficult in the past. .

いたＭＢＥにおける４元系化合物半導体の成長に大きな
見通しを与えるものである。なお先に述べた実施例では
Ｉｎソルダーを使用せず基板を支持する所謂る工ｎレス
方式についてのみ述べたが、ｌｎソルダーを使用する方
法でも適用ｑＷＱなことは言うまでもない。また発熱体
に関しても実施例では同じ円上に配置したものについて
述べたがこれもその様な配置に限定されるものでないこ
とも勿論である。更にゴえば、本発明の加熱機構はＭＢ
Ｅに限定されるものでなく例えばＭＯＣＶＤの成長基板
加熱にも使えることは言うまでもない。This provides great prospects for the growth of quaternary compound semiconductors in MBE. In the above-mentioned embodiments, only the so-called engineering-less method in which the substrate is supported without using In solder has been described, but it goes without saying that the qWQ method can also be applied to a method using In solder. Furthermore, in the embodiment, the heating elements are arranged on the same circle, but it is needless to say that the heating elements are not limited to such an arrangement. Furthermore, the heating mechanism of the present invention
Needless to say, the present invention is not limited to E, and can also be used, for example, to heat a growth substrate of MOCVD.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は、従来の単１ｆｌｉ均−巻き発熱体を袋層した
成長基板加熱機構の測定面図、第２図は、本発明の単層
２ゾーンの発熱体を袋層した成長基板加熱機構の側断面
図、第３図は、２層、３ゾーンの発熱体を袋層した成長
基板加ＰＡ機構の側断面図である。 １１．２２，２３，４３，４４，４５はＴａ、Ｗ等から
なる発熱体、１２，２８，４６は熱拡散板兼発熱体固疋
板、１４，２１，４１，４２は発熱体サセプタ。 啼１＼ 、　　　　　＼ 代理人　弁理士　高橋明夫〜　　） ゝ−７ 第　１　目 ￥Ｉ　２　図 μFig. 1 is a measured side view of a growth substrate heating mechanism in which a conventional single-layer uniformly-wound heating element is layered in a bag, and Fig. 2 is a growth substrate heating mechanism in which a single-layer, two-zone heating element of the present invention is layered in a bag. FIG. 3 is a side sectional view of a growth substrate processing PA mechanism in which heating elements in two layers and three zones are layered. 11. 22, 23, 43, 44, and 45 are heating elements made of Ta, W, etc.; 12, 28, and 46 are heat diffusion plates and heating element rigid plates; and 14, 21, 41, and 42 are heating element susceptors.啼１＼、＼Representative Patent Attorney Akio Takahashi～） ゝ-7 1st item￥I 2 Figure μ

Claims (1)

【特許請求の範囲】 １、結晶成長用基板の加熱において、発熱体が２個以上
のゾーンに独立分割され、且つ各々のゾーンを独立に温
度制御することを特徴とする結晶成長基板加熱機構。 ２、前記分割された発熱体を多層に分割して配置したこ
とを特徴とする特許請求の範囲第１項記載の結晶成長基
板加熱機構。[Scope of Claims] 1. A crystal growth substrate heating mechanism for heating a crystal growth substrate, characterized in that a heating element is independently divided into two or more zones, and the temperature of each zone is independently controlled. 2. The crystal growth substrate heating mechanism according to claim 1, wherein the divided heating elements are arranged in multiple layers.