JP4350322B2

JP4350322B2 - Heat treatment equipment

Info

Publication number: JP4350322B2
Application number: JP2001131572A
Authority: JP
Inventors: 健治大野
Original assignee: Hitachi Kokusai Electric Inc
Current assignee: Hitachi Kokusai Electric Inc
Priority date: 2001-04-27
Filing date: 2001-04-27
Publication date: 2009-10-21
Anticipated expiration: 2021-04-27
Also published as: JP2002329675A

Description

【０００１】
【発明の属する技術分野】
本発明は加熱炉を有する加熱処理装置に関する。
【０００２】
【従来の技術】
図３（ａ）は、従来の加熱炉の水平断面図を示し、図３（ｂ）は支持部材３による抵抗発熱体１の支持部分の垂直断面拡大図を示す。
耐熱壁２の内壁に接するように配された抵抗発熱体１は、耐熱壁２に埋め込まれ（差し込まれ）た支持部材３により支持される。また、抵抗発熱体１と支持部材３は同材質であるが、これらと耐熱壁２の材質は異なっており、特に熱膨張率において、抵抗発熱体１の方が耐熱壁２より大きい。
抵抗発熱体１に与える電力を増減することにより、抵抗発熱体１、耐熱壁２、支持部材３の温度が昇降温し、それに伴い各部材は熱膨張・収縮する。この際、熱膨張、収縮の向きと量が、各部材の材質や形状の差異により異なる。これに起因し、上記図３（ａ）、（ｂ）に示す加熱炉では、昇降温の際、各部材が互いに干渉し、応力が働き、抵抗発熱体１あるいは耐熱壁２や支持部材３に変形や破損が発生する。
ここで、上記した熱膨張・収縮に伴う部材間の干渉を抑制する従来の公知例として、特開平７−１８３２４３号公報が挙げられる。これは、螺旋状の抵抗発熱体に対して、それを支持する支持部材と抵抗発熱体との間に隙間を与えて支持することにより、抵抗発熱体の熱膨張・収縮による水平方向への移動に対する余裕を持たせた構造とするものである。
【０００３】
【発明が解決しようとする課題】
しかしながら、上記の公知例は抵抗発熱体が螺旋状であるが故に、熱膨張・収縮は、水平方向だけでなく、螺旋の展開方向に沿って発生するため、上記公知例が示す構造では、各部材間の干渉を取り去るには不充分であり、応力が働いた場合には、抵抗発熱体あるいは耐熱壁や支持部材に変形や破損が発生して、そのひび割れや破損により発生するパーティクルが半導体製造雰囲気を汚染するなどの問題がある。
また、上記したように、昇降温を繰り返す結果、加熱炉を構成する各部材に変形や破損を引き起こし、炉内の加熱具合が不適切な状態となったり、抵抗発熱体が切断され無通電状態となったり、隣合う抵抗発熱体間の変形により電気的に短絡が生じ異常発熱するなど、発熱体の寿命が短くなるという問題があった。
【０００４】
本発明の目的は、加熱炉の昇降温に伴う抵抗発熱体および保持部、耐熱壁の熱膨張・収縮による変形・破損を抑制すると共に、半導体製造雰囲気を汚染しない加熱炉を有する加熱処理装置を提供することにある。
【０００５】
【課題を解決するための手段】
上記目的を達成するために、本発明は特許請求の範囲に記載のような構成とするものである。すなわち、
請求項１に記載のように、
被処理体を加熱処理する処理空間を形成し、上記処理空間の外側への熱の放熱を和らげるための耐熱壁と、
上記処理空間を形成する耐熱壁の内側に設けられ、上記被処理体を加熱するための発熱体と、
上記発熱体を上記耐熱壁に保持する保持手段を有する加熱処理装置において、
上記耐熱壁に保持する保持手段は、上記発熱体の周方向に対し直角方向に移動でき、かつ上記保持手段は耐熱壁から脱落しないように保持できる空間を有する加熱処理装置とするものである。
本発明は、さらに上記保持手段の発熱体を保持している部分にも上記発熱体が移動できる空間を設けることができる。
【０００６】
【発明の実施の形態】
本発明の加熱処理装置の加熱炉（ヒータ）は、図１（ａ）に示す水平断面図、および図１（ｂ）の発熱体の支持部分の断面拡大図に示すように、被処理体を加熱処理する処理空間５を形成し、処理空間の外側への熱の放熱を和らげるための耐熱壁２を有し、上記耐熱壁２の内側に設けられ、抵抗発熱体１を耐熱壁２に保持する保持手段である支持部材３の一部を耐熱壁２に埋没させるか、また、図２に示すごとく、埋没させることなく耐熱壁２の表面部に抵抗発熱体１を保持する支持部材３を設けた加熱処理装置であって、上記耐熱壁２に設ける支持部材３は、上記抵抗発熱体１の周方向に対し直角方向に移動できる構造にしたものである。さらに、本発明の加熱炉において、上記支持部材３の発熱体を支持している部分にも発熱体の周方向に対し直角方向に移動できる空間を設けることも可能である。
【０００７】
図１（ａ）において、抵抗発熱体１を保持している支持部材３は、耐熱壁２と同等もしくは近似の熱膨張率である材質、例えば碍子を用いる構造にすることが、部材間の干渉を取り去る上で好ましく、図１（ｂ）に示すごとく、耐熱壁２に空間６が設けられ、空間６に支持部材３の基部が挿入され、支持部材３は耐熱壁２に対して抵抗発熱体１の周方向に対して直角方向に移動できる。すなわち、耐熱壁２の支持部材３が埋没している部分に、支持部材３が埋没方向に移動でき、かつ支持部材３が耐熱壁２から脱落しないように保持できる空間６が設けられ、抵抗発熱体１が膨張した際、上記支持部材３が抵抗発熱体１と一緒に動く構造になっている。
抵抗発熱体１は、例えば、帯状の発熱体等を用いることができ、円筒形の耐熱壁２の内壁に沿うように、かつ水平に配している。
また、抵抗発熱体１の両端は、電気絶縁材４を挟み合わせることで、電気的絶縁を保ちながら、構造的にはリング形状をなしている。
【０００８】
図２は、本発明の実施の形態の他の構造の一例を示す水平断面図である。この例では、耐熱壁２に耐熱壁２や支持部材３と同等もしくは近似の熱膨張率を有する材質で形成した移動保持部材７が取り付けられ、移動保持部材７に支持部材３が移動可能に取り付けられ、支持部材３は抵抗発熱体１の周方向に対して直角方向に移動できる構造にしたものであり、上記図１（ａ）、（ｂ）に示す本発明の加熱炉と同等の効果を得ることができる。
本発明の実施の形態で提案した加熱炉を構成する各部材間の熱膨張・収縮に伴う干渉を抑制する効果を得る手段は、上記の実施の形態に限るものではない。
【０００９】
【発明の効果】
本発明の加熱炉を有する加熱処理装置によれば、昇降温時に発生する耐熱壁、抵抗発熱体、支持部材の熱膨張・収縮による応力が起因となる変形や破損を抑制することができるので加熱炉の寿命を延ばすことができる。さらに、上記耐熱壁、支持部材等のひび割れや破損を抑えることにより、半導体製造雰囲気を汚染することなく、製品の歩留まりの向上をはかることができる。
【図面の簡単な説明】
【図１】本発明の実施の形態で例示した加熱炉の構成を示す模式図。
【図２】本発明の実施の形態で例示した加熱炉の構成を示す模式図。
【図３】従来の加熱炉の構成を示す模式図。
【符号の説明】
１…抵抗発熱体
２…耐熱壁
３…支持部材
４…電気絶縁材
５…処理空間
６…空間
７…移動保持部材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat treatment apparatus having a heating furnace.
[0002]
[Prior art]
FIG. 3A shows a horizontal sectional view of a conventional heating furnace, and FIG. 3B shows an enlarged vertical sectional view of a supporting portion of the resistance heating element 1 by the supporting member 3.
The resistance heating element 1 disposed so as to be in contact with the inner wall of the heat-resistant wall 2 is supported by a support member 3 embedded (inserted) in the heat-resistant wall 2. Although the resistance heating element 1 and the support member 3 are made of the same material, they are different from the material of the heat-resistant wall 2, and the resistance heating element 1 is larger than the heat-resistant wall 2 particularly in terms of the coefficient of thermal expansion.
By increasing or decreasing the power applied to the resistance heating element 1, the temperature of the resistance heating element 1, the heat-resistant wall 2, and the support member 3 is raised and lowered, and each member is thermally expanded and contracted accordingly. At this time, the direction and amount of thermal expansion and contraction differ depending on the material and shape of each member. Due to this, in the heating furnace shown in FIGS. 3 (a) and 3 (b), when the temperature is raised and lowered, the members interfere with each other and stress acts, and the resistance heating element 1, the heat-resistant wall 2 and the support member 3 are affected. Deformation or damage occurs.
Here, JP-A-7-183243 is cited as a conventional example of suppressing interference between members accompanying the above-described thermal expansion / contraction. This is because the resistance heating element is supported in a horizontal direction by thermal expansion / contraction of the resistance heating element by providing a gap between the resistance heating element and the supporting member that supports the spiral resistance heating element. In this structure, a margin is provided.
[0003]
[Problems to be solved by the invention]
However, since the resistance heating element has a spiral shape in the above known example, thermal expansion / contraction occurs not only in the horizontal direction but also in the direction of spiral development. It is not enough to remove the interference between the members. When stress is applied, the resistance heating element, heat-resistant wall, and support member are deformed or damaged, and the particles generated by the cracks and damage are produced by semiconductor manufacturing. There are problems such as polluting the atmosphere.
In addition, as described above, as a result of repeated heating and lowering, each member constituting the heating furnace is deformed or damaged, the heating condition in the furnace becomes inappropriate, or the resistance heating element is cut off and no current is supplied. There is a problem that the life of the heating element is shortened, such as an electrical short circuit due to deformation between adjacent resistance heating elements and abnormal heat generation.
[0004]
An object of the present invention is to provide a heat treatment apparatus having a heating furnace that suppresses deformation and breakage due to thermal expansion and contraction of a resistance heating element and a holding part, and a heat-resistant wall accompanying heating and lowering of the heating furnace, and does not contaminate a semiconductor manufacturing atmosphere It is to provide.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured as described in the claims. That is,
As claimed in claim 1,
Forming a treatment space for heat-treating the object to be treated, and a heat-resistant wall for reducing heat dissipation to the outside of the treatment space;
A heating element provided inside the heat-resistant wall forming the processing space, for heating the object to be processed;
In a heat treatment apparatus having a holding means for holding the heating element on the heat-resistant wall,
The holding means to be held on the heat-resistant wall is a heat treatment apparatus having a space that can move in a direction perpendicular to the circumferential direction of the heating element, and the holding means can be held so as not to fall off the heat-resistant wall.
In the present invention, a space in which the heating element can be moved can be provided in a portion of the holding means that holds the heating element.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The heating furnace (heater) of the heat treatment apparatus according to the present invention comprises a horizontal cross-sectional view shown in FIG. 1 (a) and an enlarged cross-sectional view of a supporting portion of a heating element shown in FIG. 1 (b). A heat treatment wall 5 is formed to form a treatment space 5 for heat treatment, and heat release to the outside of the treatment space. The heat resistance wall 1 is provided inside the heat resistance wall 2 and holds the resistance heating element 1 on the heat resistance wall 2. A supporting member 3 that holds the resistance heating element 1 on the surface portion of the heat-resistant wall 2 without being buried, as shown in FIG. In the heat treatment apparatus provided, the support member 3 provided on the heat-resistant wall 2 has a structure that can move in a direction perpendicular to the circumferential direction of the resistance heating element 1. Furthermore, in the heating furnace of the present invention, it is also possible to provide a space that can move in a direction perpendicular to the circumferential direction of the heating element in the portion of the support member 3 that supports the heating element.
[0007]
In FIG. 1A, the support member 3 holding the resistance heating element 1 is made of a material having a thermal expansion coefficient equivalent to or similar to that of the heat-resistant wall 2, for example, a structure using an insulator, so that interference between the members is achieved. As shown in FIG. 1 (b), a space 6 is provided in the heat-resistant wall 2, and a base portion of the support member 3 is inserted into the space 6, and the support member 3 is a resistance heating element with respect to the heat-resistant wall 2. It can move in a direction perpendicular to the circumferential direction of 1. That is, a space 6 is provided in the portion of the heat-resistant wall 2 where the support member 3 is buried, and the support member 3 can be moved in the direction of burying and can be held so that the support member 3 does not fall off the heat-resistant wall 2. When the body 1 expands, the support member 3 moves together with the resistance heating element 1.
For example, a belt-like heating element can be used as the resistance heating element 1, and the resistance heating element 1 is disposed horizontally along the inner wall of the cylindrical heat-resistant wall 2.
In addition, both ends of the resistance heating element 1 are structurally ring-shaped while maintaining electrical insulation by sandwiching the electrical insulating material 4 therebetween.
[0008]
FIG. 2 is a horizontal sectional view showing an example of another structure according to the embodiment of the present invention. In this example, a movable holding member 7 made of a material having a thermal expansion coefficient equivalent to or similar to that of the heat resistant wall 2 and the support member 3 is attached to the heat resistant wall 2, and the support member 3 is attached to the movable holding member 7 so as to be movable. The support member 3 has a structure that can move in a direction perpendicular to the circumferential direction of the resistance heating element 1, and has the same effect as the heating furnace of the present invention shown in FIGS. 1 (a) and 1 (b). Obtainable.
Means for obtaining the effect of suppressing interference associated with thermal expansion / contraction between members constituting the heating furnace proposed in the embodiment of the present invention is not limited to the above-described embodiment.
[0009]
【The invention's effect】
According to the heat treatment apparatus having the heating furnace of the present invention, the heat resistant wall, the resistance heating element, and the support member that are generated during the temperature rise and fall can be prevented from being deformed or damaged due to the stress caused by the thermal expansion / contraction. The life of the furnace can be extended. Furthermore, by suppressing cracking and breakage of the heat-resistant wall and the support member, it is possible to improve the product yield without contaminating the semiconductor manufacturing atmosphere.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a configuration of a heating furnace exemplified in an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a configuration of a heating furnace exemplified in the embodiment of the present invention.
FIG. 3 is a schematic diagram showing the configuration of a conventional heating furnace.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Resistance heating element 2 ... Heat-resistant wall 3 ... Support member 4 ... Electrical insulation material 5 ... Processing space 6 ... Space 7 ... Movement holding member

Claims

Forming a treatment space for heat-treating the object to be treated, and a heat-resistant wall for reducing heat dissipation to the outside of the treatment space;
A heating element provided inside the heat-resistant wall forming the processing space, for heating the object to be processed;
In a heat treatment apparatus having a holding means for holding the heating element on the heat-resistant wall,
The heat treatment apparatus characterized in that the holding means has a structure that can move in a direction perpendicular to the circumferential direction of the heating element.