JP3068914B2 - Vapor phase growth equipment - Google Patents
Vapor phase growth equipmentInfo
- Publication number
- JP3068914B2 JP3068914B2 JP3252354A JP25235491A JP3068914B2 JP 3068914 B2 JP3068914 B2 JP 3068914B2 JP 3252354 A JP3252354 A JP 3252354A JP 25235491 A JP25235491 A JP 25235491A JP 3068914 B2 JP3068914 B2 JP 3068914B2
- Authority
- JP
- Japan
- Prior art keywords
- substrate
- temperature
- heater
- vapor phase
- substrate holder
- 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.)
- Expired - Lifetime
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Description
【０００１】[0001]
【産業上の利用分野】本発明は、半導体等の製造に用い
られる気相成長装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor phase growth apparatus used for manufacturing semiconductors and the like.
【０００２】[0002]
【従来の技術】基板上に半導体等の薄膜を気相成長させ
て半導体等を製造する気相成長装置は、例えば図７に示
すように構成されている。2. Description of the Related Art A vapor phase growth apparatus for producing a semiconductor or the like by vapor-phase growing a thin film of a semiconductor or the like on a substrate is constructed, for example, as shown in FIG.
【０００３】この図に示すように従来の気相成長装置
は、反応炉１００内に、基板１０１を載置する基板ホル
ダ１０２と、基板ホルダ１０２を着脱自在に支持し一端
側に回転駆動装置１０３が接続されている回転軸１０４
と、基板ホルダ１０２および基板１０１を加熱するヒー
タ１０５が配設されている。As shown in FIG. 1, a conventional vapor phase growth apparatus comprises a substrate holder 102 for mounting a substrate 101 in a reaction furnace 100, a substrate holder 102 which is detachably supported, and a rotary driving device 103 at one end. Axis 104 to which is connected
And a heater 105 for heating the substrate holder 102 and the substrate 101 are provided.
【０００４】また、反応炉１００上部には、ガス供給管
１０６を介して反応炉１００内にガス（原料ガス，キャ
リアガス等）を供給するガス供給装置１０７が配設さ
れ、下部には、排気管１０８を介して反応炉１００内の
圧力調整および未反応ガス等を排気する排気装置１０９
が配設されている。A gas supply device 107 for supplying a gas (a raw material gas, a carrier gas, etc.) into the reaction furnace 100 through a gas supply pipe 106 is provided at an upper portion of the reactor 100, and an exhaust gas is provided at a lower portion thereof. Exhaust device 109 for adjusting the pressure in reactor 100 and exhausting unreacted gas and the like through pipe 108
Are arranged.
【０００５】従来の気相成長装置は上記のように構成さ
れており、基板１０１および基板ホルダ１０２をヒータ
１０５の加熱によって所定温度に上昇させると共に、回
転駆動装置１０３の回転駆動によって所定の回転数で回
転させ、ガス供給装置１０７からガス供給管１０６を通
して反応炉１００内に原料ガス（例えばＳi Ｈ2 Ｃ
ｌ2 ）をキャリアガス（例えばＨ2 ）と共に供給し、基
板１０１上に半導体等の薄膜を気相成長させる。[0005] The conventional vapor phase growth apparatus is configured as described above. The substrate 101 and the substrate holder 102 are heated to a predetermined temperature by heating the heater 105, and the rotation speed of the rotation driving device 103 is increased to a predetermined rotation speed. And feed the raw material gas (for example, SiH 2 C) from the gas supply device 107 through the gas supply pipe 106 into the reaction furnace 100.
l 2 ) is supplied together with a carrier gas (for example, H 2 ), and a thin film of a semiconductor or the like is vapor-phase grown on the substrate 101.
【０００６】ところで、上記した従来の気相成長装置で
は図８に示すように、基板ホルダ１０２の基板１０１を
載置する部分にザグリ部１０２ａを設けて、加熱させる
基板１０１の面内温度分布が均一になるようにしてい
る。In the above-mentioned conventional vapor phase growth apparatus, as shown in FIG. 8, a counterbore portion 102a is provided in a portion of the substrate holder 102 on which the substrate 101 is placed, and the in-plane temperature distribution of the substrate 101 to be heated is reduced. I try to make it even.
【０００７】ところが、上記したような基板ホルダ１０
２に基板１０１を載置する場合、基板１０１の基板ホル
ダ１０２と接している周縁部は他の部分（ザグリ部１０
２ａ）よりも温度が高くなり、スリップ等が発生する恐
れがある。特に近年、基板１０１の全面を有効に利用し
たいという要望が強く、上述したように基板１０１の周
縁部を犠牲にすることは効率的ではないと共に、周縁部
での温度差が他の部分に与える悪影響を無視できないほ
ど薄膜の均一性が求められている。However, the substrate holder 10 as described above
When the substrate 101 is placed on the substrate 2, the peripheral portion of the substrate 101 that is in contact with the substrate holder 102 has another portion (counterbore portion 10).
The temperature becomes higher than 2a), and there is a possibility that a slip or the like may occur. In particular, in recent years, there has been a strong demand to effectively use the entire surface of the substrate 101, and as described above, it is not efficient to sacrifice the peripheral portion of the substrate 101, and a temperature difference at the peripheral portion affects other portions. The uniformity of the thin film is required so that the adverse effect cannot be ignored.
【０００８】また、図７に示した従来の気相成長装置で
は、ヒータ１０５で基板ホルダ１０２を加熱して基板１
０１を加熱する構成なので、基板１０１の表側の表面か
ら輻射等による熱の逃げが大きい。Further, in the conventional vapor phase growth apparatus shown in FIG.
Since the configuration is such that the substrate 01 is heated, heat is largely released from the front surface of the substrate 101 by radiation or the like.
【０００９】このため、基板１０１が表面と裏面での温
度差等で反ると、基板１０１と基板ホルダ１０２との接
触状態が変化することによって、基板ホルダ１０２から
基板への伝熱状態が変化して基板１０１の面内温度分布
が不均一になり、スリップ等が発生する恐れがある。Therefore, when the substrate 101 warps due to a temperature difference between the front surface and the back surface, the state of heat transfer from the substrate holder 102 to the substrate changes due to the change in the contact state between the substrate 101 and the substrate holder 102. As a result, the in-plane temperature distribution of the substrate 101 becomes non-uniform, which may cause a slip or the like.
【００１０】スリップは、高温における基板１０１の面
内温度分布の発生により基板の降伏応力を越える応力が
発生することによって結晶格子に沿ってすべり変形を生
じる現象であり、高温になると基板１０１の降伏応力が
低下し、基板１０１の温度分布による熱応力等でスリッ
プが発生し易くなる。[0010] Slip is a phenomenon in which the in-plane temperature distribution of the substrate 101 at a high temperature generates a stress exceeding the yield stress of the substrate, thereby causing slip deformation along the crystal lattice. The stress is reduced, and slip is likely to occur due to thermal stress or the like due to the temperature distribution of the substrate 101.
【００１１】[0011]
【発明が解決しようとする課題】上記したように従来の
気相成長装置においては、基板ホルダ１０２上に載置さ
れる基板１０１の面内温度分布が不均一になるので、高
品質な薄膜を得ることが困難であった。As described above, in the conventional vapor phase growth apparatus, since the in-plane temperature distribution of the substrate 101 mounted on the substrate holder 102 becomes non-uniform, a high-quality thin film can be formed. It was difficult to obtain.
【００１２】本発明は上記した課題を解決する目的でな
され、基板の面内温度分布を均一にすることができる気
相成長装置を提供しようとするものである。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a vapor phase growth apparatus capable of making the in-plane temperature distribution of a substrate uniform.
【００１３】[0013]
【課題を解決するための手段】前記した課題を解決する
ために、本発明の特徴は、反応炉内に原料ガスを供給
し、反応炉内に配置した基板に薄膜を気相成長させる気
相成長装置において、基板の直径よりも小さい貫通孔を
有し、貫通孔の周縁部で基板を支持する基板ホルダと、
基板ホルダ下方で貫通孔の位置に対応して設けられた第
一の加熱手段と、第一の加熱手段とは独立して基板ホル
ダ下方で第一の加熱手段の周囲に設けられた第二の加熱
手段とを具備する気相成長装置であることにある。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a feature of the present invention is to supply a source gas into a reaction furnace and vapor-phase grow a thin film on a substrate arranged in the reaction furnace. In the growth apparatus, a substrate holder having a through-hole smaller than the diameter of the substrate, and supporting the substrate at the periphery of the through-hole,
A first heating unit provided corresponding to the position of the through hole below the substrate holder, and a second heating unit provided around the first heating unit below the substrate holder independently of the first heating unit. The present invention is to provide a vapor phase growth apparatus including a heating means.
【００１４】ここで、基板の第一の加熱手段に対して反
対側に、さらに第三の加熱手段を備えることが望まし
く、これにより、基板加熱効率の向上と基板面内温度分
布の均一化を実現することができる。Here, it is desirable to further provide a third heating means on the side of the substrate opposite to the first heating means, thereby improving the substrate heating efficiency and making the temperature distribution in the substrate surface uniform. Can be realized.
【００１５】また、基板と第一および第二の加熱手段間
に均熱板を配設しても良く、この時、均熱板は加熱手段
と接するようにしても良い。Further, a heat equalizing plate may be provided between the substrate and the first and second heating means. At this time, the heat equalizing plate may be in contact with the heating means.
【００１６】[0016]
【作用】基板の面内温度分布の均一性を実現するために
は、基板と基板ホルダの接触状態が基板が反ること等の
原因により基板ホルダから基板への伝熱状態が変化する
ことを避けるために、基板の一部のみを基板ホルダに接
するようにする必要がある。また、基板ホルダが基板と
接する部分は、基板ホルダが加熱手段からの輻射伝熱の
遮蔽となるため、基板の温度を均一にするためには、基
板ホルダの温度を基板より高温にする必要がある。In order to realize the uniformity of the in-plane temperature distribution of the substrate, it is necessary that the state of heat transfer from the substrate holder to the substrate changes due to the fact that the contact between the substrate and the substrate holder is warped. To avoid this, only part of the substrate needs to be in contact with the substrate holder. Also, where the substrate holder is in contact with the substrate, the substrate holder serves as a shield for radiant heat transfer from the heating means. In order to make the temperature of the substrate uniform, the temperature of the substrate holder must be higher than the substrate. is there.
【００１７】また、基板表面からの熱の逃げが大きくな
ると、基板表裏の温度差が大きくなって反りが大きくな
って、基板ホルダと基板との接触状態が変化しやすくな
り、基板ホルダから基板への伝熱状態が基板面内で変化
し、基板の面内温度分布が不均一になり易くなる。この
ため、基板表面からの熱の逃げを小さくすれば、基板の
反りが小さくなり、かつ、基板が反って基板ホルダとの
接触状態が変化しても、伝熱量の変化を小さくすること
が可能になり、基板の温度変化を低下させることが可能
になる。Further, when the escape of heat from the surface of the substrate increases, the temperature difference between the front and back surfaces of the substrate increases, the warpage increases, and the state of contact between the substrate holder and the substrate tends to change. Is changed in the substrate surface, and the in-plane temperature distribution of the substrate tends to be non-uniform. For this reason, if the escape of heat from the substrate surface is reduced, the warpage of the substrate is reduced, and even if the substrate warps and the contact state with the substrate holder changes, the change in the amount of heat transfer can be reduced. And it becomes possible to reduce the temperature change of the substrate.
【００１８】次に、本発明の具体的な作用について説明
する。Next, the specific operation of the present invention will be described.
【００１９】請求項１記載の第１の発明によれば、貫通
孔を形成した基板ホルダの周縁部で基板を支持し、基板
および基板ホルダをそれぞれ別々に温度制御して基板ホ
ルダの温度を基板より高温にして加熱することにより、
基板の反りによる温度変化を防止し、かつ、基板周縁部
の温度変化も防止して、基板の面内温度分布を均一化す
ることができる。According to the first aspect of the present invention, the substrate is supported by the peripheral portion of the substrate holder having the through hole, and the temperature of the substrate holder is controlled by controlling the temperature of the substrate and the substrate holder separately. By heating to a higher temperature,
The temperature change due to the warpage of the substrate is prevented, and the temperature change at the peripheral portion of the substrate is also prevented, so that the in-plane temperature distribution of the substrate can be made uniform.
【００２０】また、請求項２記載の第２の発明によれ
ば、第２の加熱手段の温度を制御して基板表面からの放
熱を制御することにより、基板の面内温度分布を均一化
することができる。According to the second aspect of the present invention, the temperature of the second heating means is controlled to control the heat radiation from the substrate surface, so that the in-plane temperature distribution of the substrate is made uniform. be able to.
【００２１】[0021]
【実施例】以下、本発明を図示の実施例に基づいて詳細
に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
【００２２】＜第１実施例＞図１は、第１実施例に係る
気相成長装置を示す概略図である。この図に示すよう
に、反応炉１内には基板２を載置した基板ホルダ３と、
ヒータ４が配設されている。<First Embodiment> FIG. 1 is a schematic view showing a vapor phase growth apparatus according to a first embodiment. As shown in this figure, a substrate holder 3 on which a substrate 2 is placed is placed in a reaction furnace 1;
A heater 4 is provided.
【００２３】基板ホルダ３には、基板２の直径よりもや
や小さい直径の貫通孔３ａが形成されており、貫通孔３
ａの周縁に形成されている凹部３ｂに基板２が載置され
ている。基板ホルダ３の下部周面には筒状の回転軸５が
着脱自在に接続されており、回転軸５は、回転駆動装置
６に連結されている。The substrate holder 3 is formed with a through hole 3 a having a diameter slightly smaller than the diameter of the substrate 2.
The substrate 2 is placed in a concave portion 3b formed on the periphery of a. A cylindrical rotary shaft 5 is detachably connected to a lower peripheral surface of the substrate holder 3, and the rotary shaft 5 is connected to a rotation driving device 6.
【００２４】ヒータ４は、基板ホルダ３の下方で回転軸
５内に基板２と基板ホルダ３の位置にほぼ対応してヒー
タ４ａ，４ｂに２分割されて同心円状に配置されてお
り、各ヒータ４ａ，４ｂにはそれぞれヒータ電源７ａ，
７ｂが接続されている。各ヒータ４ａ，４ｂには、ヒー
タ電源７ａ，７ｂの出力を制御してヒータ４ａ，４ｂの
温度を制御する温度制御装置８ａ，８ｂと、基板２の温
度を測定する放射温度計等の温度計９ａ，９ｂが接続さ
れている。温度計９ａ，９ｂは、反応炉１の上部側面に
形成した石英等から成る窓１ａ，１ｂの外に配設されて
いる。尚、温度計９ａ，９ｂは反応炉１内に設けてもよ
い。また、温度を測定する手段は、熱電対等の周知の他
の手段で行ってもよい。The heater 4 is divided into two heaters 4a and 4b in a rotary shaft 5 below the substrate holder 3 and corresponding to the positions of the substrate 2 and the substrate holder 3 and arranged concentrically. 4a and 4b have heater power supplies 7a,
7b is connected. Each of the heaters 4a, 4b has a temperature controller 8a, 8b for controlling the output of the heater power supply 7a, 7b to control the temperature of the heaters 4a, 4b, and a thermometer such as a radiation thermometer for measuring the temperature of the substrate 2. 9a and 9b are connected. The thermometers 9a and 9b are disposed outside windows 1a and 1b made of quartz or the like formed on the upper side surface of the reactor 1. Incidentally, the thermometers 9a and 9b may be provided in the reaction furnace 1. Further, the means for measuring the temperature may be performed by other known means such as a thermocouple.
【００２５】反応炉１の上部には、ガス導入管１０を介
して原料ガス，キャリアガス等のガスを反応炉１内に供
給するガス供給装置１１が接続されており、反応炉１の
下部には、ガス排出管１２を介して反応炉１内の圧力調
整および未反応ガス等を排気する排気装置１３が接続さ
れている。A gas supply device 11 for supplying a gas such as a source gas and a carrier gas into the reaction furnace 1 is connected to an upper part of the reaction furnace 1 via a gas introduction pipe 10. Is connected to an exhaust device 13 for adjusting the pressure in the reactor 1 and exhausting unreacted gas and the like via a gas discharge pipe 12.
【００２６】本実施例に係る気相成長装置は上記のよう
に構成されており、排気装置１３で反応炉１内を排気し
て反応炉内圧力を調整し、ヒータ４ａ，４ｂの加熱によ
って基板２および基板ホルダ３を所定温度に上昇させる
と共に、回転駆動装置６の回転駆動により基板ホルダ３
および基板２を回転させ、ガス供給装置１１によりキャ
リアガス（例えばＨ2 ）と共に原料ガス（例えばＳiＨ
2 Ｃｌ2 ）を反応炉１内に供給することによって、基板
２上に半導体薄膜が気相成長する。The vapor phase growth apparatus according to the present embodiment is configured as described above. The inside of the reactor 1 is evacuated by the exhaust unit 13 to adjust the pressure in the reactor, and the substrate is heated by the heaters 4a and 4b. 2 and the substrate holder 3 are raised to a predetermined temperature, and the rotation of the substrate holder 3
Then, the substrate 2 is rotated, and a source gas (for example, SiH) is mixed with a carrier gas (for example, H 2 ) by the gas supply device 11.
By supplying 2 Cl 2 ) into the reaction furnace 1, a semiconductor thin film grows on the substrate 2 in a vapor phase.
【００２７】このように本実施例では、基板２は貫通孔
３ａを通して内側のヒータ４ａで、ホルダ３は外側のヒ
ータ４ｂでそれぞれ直接加熱されることにより、加熱効
率がよくなるのでヒータ４ａ，４ｂの加熱温度を低く抑
えることができる。As described above, in this embodiment, the substrate 2 is directly heated by the inner heater 4a through the through hole 3a, and the holder 3 is directly heated by the outer heater 4b, so that the heating efficiency is improved. The heating temperature can be kept low.
【００２８】また、温度計９ａ，９ｂで基板２と基板ホ
ルダ３の温度を測定して、温度制御装置８ａ，８ｂでヒ
ータ電源７ａ，７ｂからヒータ４ａ，４ｂに流すヒータ
電流をそれぞれ制御することによって、基板２と基板ホ
ルダ３は、ヒータ４ａ，４ｂによってそれぞれ別々に加
熱温度が制御されるので、基板２を均一に加熱するため
に必要な基板ホルダ３の温度制御を基板温度との干渉を
小さくして行うことができる。この時、基板ホルダ３の
加熱温度を、基板２の加熱温度よりも少なくとも１０℃
程度以上高い状態に温度制御することにより、基板２の
周縁部が基板ホルダ３に支えられていることにより、ヒ
ータ４ｂからの輻射熱を遮蔽されることによる温度低下
を補償し、基板２の面内温度分布の均一性をより向上さ
せることができる。The temperatures of the substrate 2 and the substrate holder 3 are measured by the thermometers 9a and 9b, and the heater currents flowing from the heater power supplies 7a and 7b to the heaters 4a and 4b are controlled by the temperature controllers 8a and 8b, respectively. Accordingly, the heating temperature of the substrate 2 and the substrate holder 3 are separately controlled by the heaters 4a and 4b. Therefore, the temperature control of the substrate holder 3 necessary for uniformly heating the substrate 2 is performed by controlling the interference with the substrate temperature. It can be made smaller. At this time, the heating temperature of the substrate holder 3 is at least 10 ° C. lower than the heating temperature of the substrate 2.
By controlling the temperature to a level higher than the level, the peripheral portion of the substrate 2 is supported by the substrate holder 3 to compensate for a temperature decrease caused by shielding the radiant heat from the heater 4b. The uniformity of the temperature distribution can be further improved.
【００２９】また、前記実施例では加熱手段としてヒー
タ４を２分割した例であったが、ヒータ４を分割するこ
となく、あるいは２分割以上に分割して基板２と基板ホ
ルダ３を別々に温度制御してもよい。また、加熱手段と
してヒータ以外にも、例えば高周波コイルやランプ等に
よる加熱でもよい。In the above embodiment, the heater 4 is divided into two parts as the heating means. However, the temperature of the substrate 2 and the substrate holder 3 are separately set without dividing the heater 4 or dividing it into two or more parts. It may be controlled. In addition to the heater, the heating means may be, for example, heating using a high-frequency coil or a lamp.
【００３０】また、前記実施例では、基板２を基板ホル
ダ３の貫通孔３ａの周縁に形成した凹部３ｂの全面で支
持したが、凹部３ｂに複数の突起部を形成して、この突
起部で基板２を支持してもよい。また、周縁部に限ら
ず、基板２の中心部や、他の部分を支持してもよい。In the above-described embodiment, the substrate 2 is supported on the entire surface of the concave portion 3b formed on the peripheral edge of the through hole 3a of the substrate holder 3. However, a plurality of protrusions are formed in the concave portion 3b, and these protrusions are used. The substrate 2 may be supported. In addition, not only the peripheral part but also the central part of the substrate 2 and other parts may be supported.
【００３１】＜第２実施例＞図２は、第２実施例に係る
気相成長装置の要部を示す概略図である。本実施例で
は、基板２とヒータ４ａ間に基板２の直径とほぼ同じ径
のカーボン等の熱伝導率のよい部材から成る均熱板１４
を配置した構成であり、均熱板１４は支持棒１５で回転
軸５に支持されている。均熱板１４の固定は、他の部分
にしてもよく、他の方法でもよい。他の構成は図１に示
した第１実施例と同様である。<Second Embodiment> FIG. 2 is a schematic diagram showing a main part of a vapor phase growth apparatus according to a second embodiment. In this embodiment, a heat equalizing plate 14 made of a member having good thermal conductivity, such as carbon, having a diameter substantially equal to the diameter of the substrate 2 is provided between the substrate 2 and the heater 4a.
Are arranged, and the heat equalizing plate 14 is supported on the rotating shaft 5 by the support rod 15. The fixing of the heat equalizing plate 14 may be performed in another portion or another method. Other configurations are the same as those of the first embodiment shown in FIG.
【００３２】このように本実施例では、基板２とヒータ
４ａ間に均熱板１４を配置することにより、ヒータ４ａ
は均熱板１４の全面を均一に加熱し、均一に加熱された
均熱板１４で基板２全面を均一に加熱することができ
る。よって、基板２を加熱するヒータ４ａの温度が多少
不均一であっても、均熱板１４で温度分布を均一化して
から基板２を加熱することにより、基板２の面内温度分
布の均一性を図ることができる。As described above, in the present embodiment, by disposing the soaking plate 14 between the substrate 2 and the heater 4a, the heater 4a
Can uniformly heat the entire surface of the heat equalizing plate 14 and uniformly heat the entire surface of the substrate 2 with the uniformly heated heat equalizing plate 14. Therefore, even if the temperature of the heater 4a for heating the substrate 2 is somewhat non-uniform, the temperature distribution is made uniform by the heat equalizing plate 14, and then the substrate 2 is heated. Can be achieved.
【００３３】また、基板ホルダ３は、基板２ほどの均熱
性が要求されないので、ヒータ４ｂと基板ホルダ３の間
には上記したような均熱板を設けても設けなくてもよ
い。均熱板を設ける場合は、基板２の径よりも均熱板の
径を大きくして、ヒータ４ｂと基板ホルダ３の間に配設
すればよい。Since the substrate holder 3 is not required to be as uniform as the substrate 2, the above-mentioned heat equalizing plate may or may not be provided between the heater 4b and the substrate holder 3. When providing a soaking plate, the diameter of the soaking plate may be made larger than the diameter of the substrate 2 and disposed between the heater 4 b and the substrate holder 3.
【００３４】＜第３実施例＞図３は、第３実施例に係る
気相成長装置の要部を示す概略図である。本実施例で
は、基板２と基板ホルダ３の下方に位置してヒータ４
ａ，４ｂの表面にほぼ接するようにして均熱板１４を配
置した構成であり、均熱板１４はヒータ上にのってい
る。他の構成は図１に示した第１実施例と同様である。
均熱板１４は、基板２とほぼ同じ径の位置等で２分割以
上に分割されていてもよい。<Third Embodiment> FIG. 3 is a schematic view showing a main part of a vapor phase growth apparatus according to a third embodiment. In this embodiment, the heater 4 is located below the substrate 2 and the substrate holder 3.
The heat equalizing plate 14 is arranged so as to be almost in contact with the surfaces of the heaters a and 4b, and the heat equalizing plate 14 is mounted on the heater. Other configurations are the same as those of the first embodiment shown in FIG.
The heat equalizing plate 14 may be divided into two or more parts at a position having substantially the same diameter as the substrate 2.
【００３５】このように本実施例では、ヒータ４ａ，４
ｂの表面に接するようにして均熱板１４を配置すること
により、前記同様ヒータ４ａ，４ｂに温度の不均一があ
っても均一に加熱された均熱板１４で間接的に基板２，
基板センサ３を加熱することにより、基板２の面内温度
分布の均一性を図ることができる。しかも、均熱板１４
とヒータ４ａ，４ｂが接しているために、均熱板１４と
ヒータ４ａ，４ｂの温度がほぼ等しくなり、ヒータ４
ａ，４ｂの温度を低下させ、ヒータ４ａ，４ｂの寿命を
長くしたり、部材よりの不純物の放出を低減させること
が可能となる。また、均熱部分の構成も単純になる。As described above, in this embodiment, the heaters 4a, 4a
b, the heaters 4a and 4b are indirectly heated by the uniform heating plate 14 even if the heaters 4a and 4b have non-uniform temperatures.
By heating the substrate sensor 3, uniformity of the in-plane temperature distribution of the substrate 2 can be achieved. Moreover, the heat equalizing plate 14
And the heaters 4a and 4b are in contact with each other, so that the temperatures of the heat equalizing plate 14 and the heaters 4a and 4b become substantially equal,
By lowering the temperatures of the heaters 4a and 4b, the life of the heaters 4a and 4b can be prolonged, and the emission of impurities from members can be reduced. In addition, the configuration of the soaking section becomes simple.
【００３６】＜第４実施例＞図４は、第４実施例に係る
気相成長装置の要部を示す概略図である。本実施例で
は、基板２と基板ホルダ３の下方に位置してヒータ４
ａ，４ｂの下側に均熱板１４を配置した構成であり、均
熱板１４は回転軸５の内周面に支持されている。他の構
成は図１に示した第１実施例と同様である。<Fourth Embodiment> FIG. 4 is a schematic diagram showing a main part of a vapor phase growth apparatus according to a fourth embodiment. In this embodiment, the heater 4 is located below the substrate 2 and the substrate holder 3.
The heat equalizing plate 14 is disposed below the a and 4b. The heat equalizing plate 14 is supported on the inner peripheral surface of the rotating shaft 5. Other configurations are the same as those of the first embodiment shown in FIG.
【００３７】このように本実施例では、ヒータ４ａ，４
ｂの下側に均熱板１４を配置することにより、ヒータ４
ａ，４ｂの温度の不均一性を緩和することができる。ま
た、ヒータ４ａ，４ｂの熱が直接基板２を加熱するため
に、加熱効率がよくなり、ヒータ４ａ，４ｂの温度を低
く抑えることができる。As described above, in this embodiment, the heaters 4a, 4a
b, the heater 4
The non-uniformity of the temperatures a and 4b can be reduced. Further, since the heat of the heaters 4a and 4b directly heats the substrate 2, the heating efficiency is improved, and the temperatures of the heaters 4a and 4b can be kept low.
【００３８】＜第５実施例＞図５は、第５実施例に係る
気相成長装置を示す概略図である。この図に示すよう
に、反応炉１内の下部には基板２を載置した基板ホルダ
３と、第１のヒータ１６と、均熱板１４とが配設され、
反応炉１内の上部には、複数の孔１７ａが形成されてい
る円盤状の整流板１７が配設されている。<Fifth Embodiment> FIG. 5 is a schematic diagram showing a vapor phase growth apparatus according to a fifth embodiment. As shown in this figure, a substrate holder 3 on which a substrate 2 is placed, a first heater 16, and a heat equalizing plate 14 are provided in a lower portion of the reactor 1.
A disk-shaped current plate 17 having a plurality of holes 17a is provided in an upper portion of the reactor 1.
【００３９】均熱板１４は、基板ホルダ３の下部に複数
の支持棒１５を介して配設されており、均熱板１４の下
部周面には筒状の回転軸５が接続されている。回転軸５
は、回転駆動装置６に連結されている。The heat equalizing plate 14 is disposed below the substrate holder 3 via a plurality of support rods 15, and the cylindrical rotating shaft 5 is connected to the lower peripheral surface of the heat equalizing plate 14. . Rotary axis 5
Is connected to the rotary drive 6.
【００４０】基板ホルダ３には、基板２の直径よりもや
や小さい直径の貫通孔３ａが形成されており、貫通孔３
ａの周縁に形成されている凹部３ｂに基板２が載置され
ている。The substrate holder 3 is formed with a through hole 3 a having a diameter slightly smaller than the diameter of the substrate 2.
The substrate 2 is placed in a concave portion 3b formed on the periphery of a.
【００４１】第１のヒータ１６は、均熱板１４の下方で
回転軸５内に配置されており、第１のヒータ１６にはヒ
ータ電源７と、ヒータ電源７の出力を制御して第１のヒ
ータ１６の温度を制御する温度制御装置８と、基板２の
温度を測定する放射温度計等の温度計１８が接続されて
いる。温度計１８は、反応炉１の上部側面に形成した石
英等からなる窓１ａの外に配設されている。尚、温度計
１８は反応炉１内に設けてもよい。The first heater 16 is disposed below the soaking plate 14 in the rotary shaft 5. The first heater 16 controls the heater power supply 7 and the output of the heater power supply 7 to control the first heater 16. A temperature controller 8 for controlling the temperature of the heater 16 and a thermometer 18 such as a radiation thermometer for measuring the temperature of the substrate 2 are connected. The thermometer 18 is provided outside a window 1 a made of quartz or the like formed on the upper side surface of the reaction furnace 1. Incidentally, the thermometer 18 may be provided in the reaction furnace 1.
【００４２】反応炉１の整流板１７上に位置する上部側
面には、ガス導入管１０を介して原料ガス，キャリアガ
ス等のガスを反応炉１内に供給するガス供給装置１１が
接続されており、反応炉１の下部には、ガス排出管１２
を介して反応炉１内の圧力調整および未反応ガス等を排
気する排気装置１３が接続されている。A gas supply device 11 for supplying a gas such as a raw material gas and a carrier gas into the reaction furnace 1 through a gas introduction pipe 10 is connected to an upper side surface of the reaction furnace 1 located on the straightening plate 17. In the lower part of the reactor 1, a gas discharge pipe 12 is provided.
An exhaust device 13 for adjusting the pressure in the reaction furnace 1 and exhausting the unreacted gas and the like is connected via the.
【００４３】また、反応炉１の上部には、石英等の熱線
を透過する材質から成る窓１９が形成されており、窓１
９の上方には熱板２０と、この熱板２０を加熱する第２
のヒータ２１が配設されている。A window 19 made of a material that transmits heat rays, such as quartz, is formed in the upper part of the reaction furnace 1.
9 and a second heating plate 20 for heating the heating plate 20.
Heater 21 is provided.
【００４４】第２のヒータ２１にはヒータ電源２２と、
ヒータ電源２２の出力を制御して第２のヒータ２１の温
度を制御する温度制御装置２３と、熱板２０の温度を測
定する放射温度計等の温度計２４が接続されている。The second heater 21 has a heater power supply 22,
A temperature controller 23 that controls the output of the heater power supply 22 to control the temperature of the second heater 21 and a thermometer 24 such as a radiation thermometer that measures the temperature of the hot plate 20 are connected.
【００４５】本実施例に係る気相成長装置は上記のよう
に構成されており、排気装置１３で反応炉１内を排気し
て反応炉内圧力を調整し、第１のヒータ１６の加熱によ
って下方（裏側）から基板２および基板ホルダ３を所定
温度に上昇させると共に、第２のヒータ２１により熱板
２０を加熱し、熱板２０によって基板２および基板ホル
ダ３よりの放熱量を制御する。そして、回転駆動装置６
の回転駆動により基板ホルダ３および基板２を所定の回
転速度で回転させ、ガス供給装置１１によりキャリアガ
ス（例えばＨ2 ）と共に原料ガス（例えばＳiＨ2 Ｃｌ
2 ）を反応炉１内に供給することによって、基板２上に
半導体薄膜が気相成長する。The vapor phase growth apparatus according to the present embodiment is configured as described above. The inside of the reaction furnace 1 is evacuated by the exhaust device 13 to adjust the pressure in the reaction furnace. The temperature of the substrate 2 and the substrate holder 3 is raised from below (back side) to a predetermined temperature, the heating plate 20 is heated by the second heater 21, and the amount of heat radiation from the substrate 2 and the substrate holder 3 is controlled by the heating plate 20. And the rotation drive device 6
The substrate holder 3 and the substrate 2 are rotated at a predetermined rotation speed by the rotational driving of the source gas, and the source gas (eg, SiH 2 Cl) together with the carrier gas (eg, H 2 ) is supplied by the gas supply device 11.
2 ) is supplied into the reaction furnace 1 so that a semiconductor thin film grows on the substrate 2 in vapor phase.
【００４６】この時、温度計１８で基板２の温度を測定
して基板２が所定の温度（例えば１０００℃）に制御さ
れるように、温度制御装置８によってヒータ電源７から
第１のヒータ１６に流すヒータ電流を制御する。また、
第２のヒータ２１によって加熱される熱板２０の温度が
所定の温度（例えば基板２の温度と同じ１０００℃）に
制御されるように、温度制御装置２３によってヒータ電
源２２から第２のヒータ２１に流すヒータ電流を制御す
る。At this time, the temperature of the substrate 2 is measured by the thermometer 18 so that the temperature of the substrate 2 is controlled to a predetermined temperature (for example, 1000 ° C.) by the temperature controller 8 from the heater power supply 7 to the first heater 16. To control the heater current flowing through the heater. Also,
The temperature control device 23 controls the second heater 21 from the heater power supply 22 so that the temperature of the hot plate 20 heated by the second heater 21 is controlled to a predetermined temperature (for example, 1000 ° C. which is the same as the temperature of the substrate 2). To control the heater current flowing through the heater.
【００４７】図６は、熱板２０の温度と基板２の面内温
度分布の関係を示す実験結果であり、基板２の中心部の
温度を１０００℃に制御した際の基板２の周縁部の温度
を熱板温度に対してプロットしてある。FIG. 6 is an experimental result showing the relationship between the temperature of the hot plate 20 and the in-plane temperature distribution of the substrate 2. The temperature at the center of the substrate 2 is controlled to 1000.degree. Temperature is plotted against hot plate temperature.
【００４８】この実験結果から明らかなように、基板２
の温度がほぼ１０００℃の場合には、熱板２０の温度を
９００〜１２００℃の範囲に設定した場合（即ち、熱板
２０の温度を基板２の温度に対して−１００〜２００℃
の範囲に設定する）に、基板２の面内温度分布の均一性
が良好になった。As is clear from the experimental results, the substrate 2
Is approximately 1000 ° C., the temperature of the hot plate 20 is set in the range of 900 to 1200 ° C. (that is, the temperature of the hot plate 20 is −100 to 200 ° C. with respect to the temperature of the substrate 2).
In this case, the uniformity of the in-plane temperature distribution of the substrate 2 was improved.
【００４９】このように、基板２をその下側から第１の
ヒータ１６によって加熱する以外に、基板２をその上方
から第２のヒータ２１で加熱される熱板２０で加熱する
ことによって、基板２の表面からの輻射等による放熱を
大幅に低減することができるので、基板加熱効率の向上
と基板面内温度分布の均一化を図ることができる。As described above, in addition to the substrate 2 being heated from below by the first heater 16, the substrate 2 is heated from above by the heating plate 20 which is heated by the second heater 21. Since heat radiation due to radiation or the like from the surface of the substrate 2 can be significantly reduced, the substrate heating efficiency can be improved and the temperature distribution in the substrate surface can be made uniform.
【００５０】また、前記実施例では、第２のヒータ２１
と熱板２０を反応炉１の外に配設したが、反応炉１内の
基板２の上方に配設してもよく、また、熱板２０を使用
してもしなくてもよい。In the above embodiment, the second heater 21
Although the heating plate 20 and the heating plate 20 are provided outside the reaction furnace 1, the heating plate 20 may be provided above the substrate 2 in the reaction furnace 1, and the heating plate 20 may or may not be used.
【００５１】また、前記実施例では第２の加熱手段とし
てヒータを用いたが、これ以外にも例えば高周波コイル
等による加熱でもよい。In the above-described embodiment, a heater is used as the second heating means. Alternatively, heating using a high-frequency coil or the like may be used.
【００５２】[0052]
【発明の効果】以上、実施例に基づいて具体的に説明し
たように本発明によれば、基板の面内温度分布の均一化
を図ることができるので、基板にスリップ等が発生する
ことが防止され、高品質の薄膜を得ることができる。As described above, according to the present invention, the in-plane temperature distribution of the substrate can be made uniform, so that a slip or the like occurs on the substrate. A high quality thin film can be obtained.
【００５３】また、加熱効率が向上することにより加熱
手段の温度を下げることができるので、反応炉内で不純
物が発生することが抑制され、高品質の薄膜を成長させ
ることができる。Further, since the temperature of the heating means can be lowered by improving the heating efficiency, generation of impurities in the reaction furnace is suppressed, and a high quality thin film can be grown.
【図１】本発明の第１実施例に係る気相成長装置を示す
概略図である。FIG. 1 is a schematic diagram showing a vapor phase growth apparatus according to a first embodiment of the present invention.
【図２】本発明の第２実施例に係る気相成長装置の要部
を示す概略図である。FIG. 2 is a schematic view showing a main part of a vapor phase growth apparatus according to a second embodiment of the present invention.
【図３】本発明の第３実施例に係る気相成長装置の要部
を示す概略図である。FIG. 3 is a schematic view showing a main part of a vapor phase growth apparatus according to a third embodiment of the present invention.
【図４】本発明の第４実施例に係る気相成長装置の要部
を示す概略図である。FIG. 4 is a schematic view showing a main part of a vapor phase growth apparatus according to a fourth embodiment of the present invention.
【図５】本発明の第５実施例に係る気相成長装置を示す
概略図である。FIG. 5 is a schematic view showing a vapor phase growth apparatus according to a fifth embodiment of the present invention.
【図６】熱板温度と基板面内温度分布の関係を示す図で
ある。FIG. 6 is a diagram showing a relationship between a hot plate temperature and a temperature distribution in a substrate surface.
【図７】従来の気相成長装置を示す概略図である。FIG. 7 is a schematic view showing a conventional vapor phase growth apparatus.
【図８】従来の気相成長装置の基板ホルダを示す概略図
である。FIG. 8 is a schematic view showing a substrate holder of a conventional vapor phase growth apparatus.
１ 反応炉 ２ 基板 ３ 基板ホルダ ３ａ 貫通孔 ４，４ａ，４ｂ ヒータ ８，８ａ，８ｂ，２３ 温度制御装置 ９ａ，９ｂ，１８，２４ 温度計 １０ ガス供給装置 １４ 均熱板 １５ 整流板 １６ 第１のヒータ ２０ 熱板 ２１ 第２のヒータ DESCRIPTION OF SYMBOLS 1 Reaction furnace 2 Substrate 3 Substrate holder 3a Through hole 4, 4a, 4b Heater 8, 8a, 8b, 23 Temperature control device 9a, 9b, 18, 24 Thermometer 10 Gas supply device 14 Heat equalizing plate 15 Straightening plate 16 First Heater 20 hot plate 21 second heater
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) H01L 21/205 ──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. 7 , DB name) H01L 21/205
Claims (4)
炉内に配置した基板に薄膜を気相成長させる気相成長装
置において、 前記基板の直径よりも小さい貫通孔を有し、当該貫通孔
の周縁部で当該基板を支持する基板ホルダと、 前記基板ホルダ下方で前記貫通孔の位置に対応して設け
られた第一の加熱手段と、 前記第一の加熱手段とは独立して前記基板ホルダ下方で
前記第一の加熱手段の周囲に設けられた第二の加熱手段
とを具備することを特徴とする気相成長装置。1. A vapor growth apparatus for supplying a source gas into a reaction furnace and vapor-growing a thin film on a substrate arranged in the reaction furnace, wherein the apparatus has a through hole smaller than the diameter of the substrate. A substrate holder that supports the substrate at the periphery of the through hole, a first heating unit provided corresponding to the position of the through hole below the substrate holder, and the first heating unit is independently provided. A second heating means provided around the first heating means below the substrate holder.
反対側に配設した第三の加熱手段を具備することを特徴
とする請求項１に記載の気相成長装置。2. The vapor phase growth apparatus according to claim 1, further comprising a third heating means disposed on the substrate on a side opposite to the first heating means.
段間に配設された均熱板を具備することを特徴とする請
求項１又は請求項２に記載の気相成長装置。3. The vapor phase growth apparatus according to claim 1, further comprising a heat equalizing plate disposed between said substrate and said first and second heating means.
れた均熱板を具備することを特徴とする請求項１、請求
項２又は請求項３に記載の気相成長装置。4. The vapor phase growth apparatus according to claim 1, further comprising a heat equalizing plate disposed so as to be in contact with said heating means.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3252354A JP3068914B2 (en) | 1991-09-30 | 1991-09-30 | Vapor phase growth equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3252354A JP3068914B2 (en) | 1991-09-30 | 1991-09-30 | Vapor phase growth equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0590165A JPH0590165A (en) | 1993-04-09 |
| JP3068914B2 true JP3068914B2 (en) | 2000-07-24 |
Family
ID=17236126
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3252354A Expired - Lifetime JP3068914B2 (en) | 1991-09-30 | 1991-09-30 | Vapor phase growth equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3068914B2 (en) |
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|---|---|---|---|---|
| US8809086B2 (en) | 2000-10-17 | 2014-08-19 | Osram Gmbh | Method for fabricating a semiconductor component based on GaN |
| US7700959B2 (en) | 2004-04-27 | 2010-04-20 | Sony Corporation | Semiconductor light-emitting device, semiconductor light-emitting apparatus, and method of manufacturing semiconductor light-emitting device |
| US9231159B2 (en) | 2011-04-27 | 2016-01-05 | Nichia Corporation | Method of manufacturing nitride semiconductor light emitting element having thick metal bump |
| US9530950B2 (en) | 2011-04-27 | 2016-12-27 | Nichia Corporation | Method of manufacturing nitride semiconductor light emitting element having thick metal bump |
| US8658441B2 (en) | 2011-05-19 | 2014-02-25 | Nichia Corporation | Method of manufacturing nitride semiconductor light emitting element |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0590165A (en) | 1993-04-09 |
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