JPH06310454A - Hot-wall type heat treatment device - Google Patents

Abstract

PURPOSE:To uniformize film thickness by each batch by arranging inner heaters through heat insulating plates for each substrate to be heated in addition to external heaters so as to allow partial temperature increase and compensate gas nonuniformity due to the gas turbulence in a reaction chamber. CONSTITUTION:Inner heaters 11 are arranged vertically by being sandwiched by heat insulators 12 in a boat 6 in a process tube 2 which is surrounded by external heaters 1, and semiconductor substrate 5 are supported horizontally between the sandwiched heaters. The inner heater 11 is held by the frame of the boat 6 and the heat insulating plate 12 is formed of SiC or quartz. Based on the internal temperature distribution measured by the thermocouple 10 of the device, inputs to each zone of the external heater 1 and to each inner heater 11 are controlled and uniform temperature distribution is provided. Temperature range to be controlled can be adjusted by changing the number, thickness and material of the inner heater 11. Thus, partial temperature increase is allowed, steep thermal gradient is formed and uniform reaction of the substrates to be heated is improved.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、バッチ式の減圧ＣＶＤ
および酸化、拡散に用いるホットウォール型熱処理装置
に関する。BACKGROUND OF THE INVENTION The present invention relates to a batch type low pressure CVD.
And a hot wall type heat treatment apparatus used for oxidation and diffusion.

【０００２】[0002]

【従来の技術】半導体基板上への薄膜形成のためのＣＶ
Ｄあるいは半導体基板の酸化、拡散を行うホットウォー
ル型熱処理装置は、反応室の外側から高周波加熱、ヒー
タ加熱等を用いて半導体基板の加熱を行う装置である。
図２は従来のヒータ加熱によるホットウォール型熱処理
装置を示し、複数のゾーンに分割された外部ヒータ１に
囲まれた内径約250mm 、高さ約1000mmのプロセスチュー
ブ２の中に、内部チューブ３を介してキャップ４の上に
半導体基板５を収容するボート６が立てられている。キ
ャップ４は、成膜、熱処理の均一性を得るために、下方
への熱伝搬を防ぐ炭化けい素 (SiＣ) あるいは石英製の
複数の断熱板７の上にかぶせられている。そして、プロ
セスチューブ２の内部は排気口８を通じて排気可能であ
り、またガス導入管９を通じて反応ガスを導入可能であ
る。半導体基板５の温度制御は、予め熱電対10を用いて
炉内の温度プロファイルを測定し、そのときの外部ヒー
タ１の温度を熱電対10を通じて記憶しそれを基にして制
御するプロファイル制御か、あるいは熱電対10を炉内に
入れたまま、絶えず参照しながら制御するカスケード制
御によって行われている。CV for forming a thin film on a semiconductor substrate
The hot wall type heat treatment device for oxidizing or diffusing the semiconductor substrate D or the semiconductor substrate is a device for heating the semiconductor substrate by using high frequency heating, heater heating, or the like from the outside of the reaction chamber.
FIG. 2 shows a conventional hot wall type heat treatment apparatus by heating a heater. An inner tube 3 is placed in a process tube 2 having an inner diameter of about 250 mm and a height of about 1000 mm surrounded by an outer heater 1 divided into a plurality of zones. A boat 6 for housing the semiconductor substrate 5 is erected on the cap 4 via the cap. The cap 4 is placed on a plurality of heat insulating plates 7 made of silicon carbide (SiC) or quartz that prevent downward heat transfer in order to obtain uniform film formation and heat treatment. The inside of the process tube 2 can be exhausted through the exhaust port 8 and the reaction gas can be introduced through the gas introduction pipe 9. The temperature control of the semiconductor substrate 5 may be profile control in which the temperature profile in the furnace is measured in advance using the thermocouple 10 and the temperature of the external heater 1 at that time is stored through the thermocouple 10 and controlled based on the temperature profile. Alternatively, it is carried out by a cascade control in which the thermocouple 10 is kept in the furnace while being constantly referred to.

【０００３】[0003]

【発明が解決しようとする課題】しかし上記の装置で
は、プロセスチューブ２の外から加熱しているため、細
かな温度制御が難しい。特に、プロセスチューブ内での
均一性が得にくい原料ガスを用いた減圧ＣＶＤによる成
膜などのように、急峻な温度勾配をつけることによって
ガスの不均一性を補償してバッチ内の膜厚の均一性を得
る場合、対応することができない。However, in the above apparatus, since the process tube 2 is heated from outside, it is difficult to control the temperature in detail. In particular, a film with a steep temperature gradient is used to compensate for the non-uniformity of the gas, such as film formation by low pressure CVD using a source gas in which uniformity in the process tube is difficult to obtain, so If you want to get uniformity, you can't do it.

【０００４】本発明の目的は、上記の問題を解決し、細
かな温度制御と、急峻な温度勾配をつけることもでき、
被処理基板間の反応の均一性が得られるホットウォール
型熱処理装置を提供することにある。The object of the present invention is to solve the above problems, to enable fine temperature control and to provide a steep temperature gradient,
It is an object of the present invention to provide a hot wall type heat treatment apparatus which can obtain a uniform reaction between substrates to be processed.

【０００５】[0005]

【課題を解決するための手段】上記の目的を達成するた
めに、本発明のホットウォール型熱処理装置は、軸方向
が鉛直の筒状反応室内に被処理基板が、複数枚ずつが相
互間および両端に断熱板を介して内部加熱体を備えて水
平に保持され、その筒状反応室を囲んで外部加熱体を備
えたものとする。そして、被処理基板が半導体基板であ
ること、断熱板が炭化けい素あるいは石英からなること
が有効である。In order to achieve the above object, the hot wall type heat treatment apparatus of the present invention comprises a plurality of substrates to be treated, which are arranged in a cylindrical reaction chamber whose axial direction is vertical, and between the substrates. An internal heating element is provided at both ends via a heat insulating plate to be held horizontally, and an external heating element is provided so as to surround the cylindrical reaction chamber. It is effective that the substrate to be processed is a semiconductor substrate and the heat insulating plate is made of silicon carbide or quartz.

【０００６】[0006]

【作用】外部加熱体のほかに、複数枚の被加熱基板ごと
に断熱板を介して内部加熱体を配置することにより、部
分的な昇温が可能になり、反応室内のガスの乱流などに
よって、基板間の成膜膜厚あるいは不純物濃度などの均
一性が得にくい場合も、薄い領域で急峻な温度勾配をつ
けることができ、基板間の反応の均一性が向上する。[Function] In addition to the external heating element, by arranging the internal heating element via the heat insulating plate for each of a plurality of substrates to be heated, it is possible to partially raise the temperature, and turbulent flow of gas in the reaction chamber, etc. By this, even when it is difficult to obtain the uniformity of the film thickness or the impurity concentration between the substrates, a steep temperature gradient can be provided in the thin region, and the uniformity of the reaction between the substrates is improved.

【０００７】[0007]

【実施例】図１は本発明の一実施例のホットウォール型
熱処理装置を示し、図１と共通の部分には同一の符号が
付されている。この装置では、外部ヒータ１に囲まれた
プロセスチューブ２の中のボート６に内部ヒータ11を断
熱板12ではさんで複数段に配置され、半導体基板５はそ
れらの中間に水平に支持されている。図３はその構造の
詳細を示し、内部ヒータ11はボート６の枠体61に保持さ
れている。断熱板12は、SiＣあるいは石英からなる。こ
の装置を用い、熱電対10によって測定した内部温度分布
に基づき、外部ヒータ１の各ゾーンおよび各内部ヒータ
11への入力を制御し、均一な温度分布を得る。内部ヒー
タ11の枚数、厚さ、材質を変えることにより制御する温
度の幅を調整することができる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a hot wall type heat treatment apparatus according to an embodiment of the present invention, and the same parts as those in FIG. In this apparatus, an internal heater 11 is arranged in a plurality of stages in a boat 6 in a process tube 2 surrounded by an external heater 1 with a heat insulating plate 12, and a semiconductor substrate 5 is horizontally supported in the middle thereof. . FIG. 3 shows the details of the structure, and the internal heater 11 is held by the frame 61 of the boat 6. The heat insulating plate 12 is made of SiC or quartz. Using this device, based on the internal temperature distribution measured by the thermocouple 10, each zone of the external heater 1 and each internal heater
Control the input to 11 to get a uniform temperature distribution. By changing the number, thickness, and material of the internal heaters 11, it is possible to adjust the temperature range to be controlled.

【０００８】[0008]

【発明の効果】本発明によれば、ホットウォール型熱処
理装置に外部ヒータのほかにボート内蔵の補助ヒータを
備え、併せて制御することにより、部分的な昇温が可能
になり、急峻な熱勾配も形成でき、被加熱基板間の反応
の均一性を向上させることが可能になり、特にガス流中
での半導体基板上の成膜あるいは酸化、拡散における、
成膜膜圧あるいは不純物濃度の均一化に有効に使用でき
る。According to the present invention, a hot wall type heat treatment apparatus is provided with an auxiliary heater built into a boat in addition to an external heater, and by controlling it together, a partial temperature rise becomes possible and a steep heat is generated. A gradient can also be formed, which makes it possible to improve the homogeneity of the reaction between the heated substrates, particularly in the film formation on the semiconductor substrate in the gas flow or the oxidation and diffusion.
It can be effectively used for uniforming film formation film pressure or impurity concentration.

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

【図１】本発明の一実施例の熱処理装置の縦断面図FIG. 1 is a vertical sectional view of a heat treatment apparatus according to an embodiment of the present invention.

【図２】従来のホットウォール型熱処理装置の縦断面図FIG. 2 is a vertical sectional view of a conventional hot wall type heat treatment apparatus.

【図３】本発明の一実施例の熱処理装置のボート部縦断
面図FIG. 3 is a vertical sectional view of a boat portion of the heat treatment apparatus according to the embodiment of the present invention.

【符号の説明】[Explanation of symbols]

１ 外部ヒータ ２ プロセスチューブ ４ キャップ ５ 半導体基板 ６ ボート ８ 排気口 ９ ガス導入管 １０ 熱電対 １１ 内部ヒータ ７、１２ 断熱板 1 External Heater 2 Process Tube 4 Cap 5 Semiconductor Substrate 6 Boat 8 Exhaust Port 9 Gas Inlet Pipe 10 Thermocouple 11 Internal Heater 7, 12 Insulation Plate

Claims (4)

【特許請求の範囲】[Claims] 【請求項１】軸方向が鉛直の筒状反応室内に被処理基板
が、複数枚ずつが相互間および両端に断熱板を介して内
部加熱体を備えて水平に保持され、その筒状加熱体を囲
んで外部加熱体を備えたことを特徴とするホットウォー
ル型熱処理装置。1. A cylindrical reaction chamber having a vertical axial direction in which a plurality of substrates to be treated are held horizontally by an internal heating element provided between each of the substrates and at both ends thereof via heat insulating plates. A hot-wall type heat treatment apparatus characterized by comprising an external heating body surrounding the. 【請求項２】被処理基板が半導体基板である請求項１記
載のホットウォール型熱処理装置。2. The hot wall heat treatment apparatus according to claim 1, wherein the substrate to be processed is a semiconductor substrate. 【請求項３】断熱板が炭化けい素からなる請求項１ある
いは２記載のホットウォール型熱処理装置。3. The hot wall type heat treatment apparatus according to claim 1, wherein the heat insulating plate is made of silicon carbide. 【請求項４】断熱板が石英からなる請求項１あるいは２
記載のホットウォール型熱処理装置。4. The heat insulating plate is made of quartz.
The hot wall type heat treatment apparatus described.