JP2644660B2 - Ceramic heater - Google Patents
Ceramic heaterInfo
- Publication number
- JP2644660B2 JP2644660B2 JP4321921A JP32192192A JP2644660B2 JP 2644660 B2 JP2644660 B2 JP 2644660B2 JP 4321921 A JP4321921 A JP 4321921A JP 32192192 A JP32192192 A JP 32192192A JP 2644660 B2 JP2644660 B2 JP 2644660B2
- Authority
- JP
- Japan
- Prior art keywords
- ceramic heater
- ceramic
- thermocouple
- screw portion
- embedded
- 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
Links
Landscapes
- Resistance Heating (AREA)
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、緻密なセラミックス基
体中に高融点金属からなる抵抗発熱体を埋設してなる好
ましくは半導体ウェハー加熱用のセラミックスヒーター
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic heater for heating a semiconductor wafer, preferably comprising a resistance heating element made of a high-melting metal embedded in a dense ceramic substrate.
【０００２】[0002]
【従来の技術】従来、半導体製造装置等における熱源と
しては、いわゆるステンレスヒーターや間接加熱方式の
ものが一般的であった。しかし、これらの熱源を用いる
と、ハロゲン系腐食ガスの作用によってパーティクルが
発生したり、熱効率が悪いといった問題があった。こう
した問題を解決するため、本発明者らは、緻密質セラミ
ックスからなる円盤状の基体の内部に、高融点金属から
なる抵抗発熱体を埋設したセラミックスヒーターを提案
した。2. Description of the Related Art Conventionally, as a heat source in a semiconductor manufacturing apparatus or the like, a so-called stainless steel heater or an indirect heating system has been generally used. However, when these heat sources are used, there are problems such as generation of particles due to the action of the halogen-based corrosive gas and poor thermal efficiency. In order to solve these problems, the present inventors have proposed a ceramic heater in which a resistance heating element made of a high melting point metal is embedded in a disk-shaped base made of dense ceramics.
【０００３】上述したセラミックスヒーターにおいて
は、加熱時の温度制御のためセラミックスヒーターの温
度を測定する必要があり、そのためセラミックスヒータ
ーに温度測定用の熱電対を設けていた。図６は従来の熱
電対の取り付け方法の一例を示す図である。図６におい
て、２１は窒化珪素等のセラミックスよりなるセラミッ
クス基体、２２はＷ、Ｍｏ等の高融点金属よりなる抵抗
発熱体、２３はウェハー加熱面２１ａ以外の面に設けた
熱電対の取り付け穴、２４は熱電対、２５は熱電対を保
護するためのシース、２６はシース２５を取り付け穴２
３に固定するための接着用ガラスである。In the above-described ceramic heater, it is necessary to measure the temperature of the ceramic heater in order to control the temperature during heating. Therefore, the ceramic heater is provided with a thermocouple for temperature measurement. FIG. 6 is a diagram showing an example of a conventional method of attaching a thermocouple. In FIG. 6, 21 is a ceramic base made of ceramics such as silicon nitride, 22 is a resistance heating element made of a high melting point metal such as W or Mo, 23 is a thermocouple mounting hole provided on a surface other than the wafer heating surface 21a, 24 is a thermocouple, 25 is a sheath for protecting the thermocouple, and 26 is a sheath 25 for attaching the sheath 25.
3 is an adhesive glass for fixing to 3.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、図６に
示す従来の熱電対取り付け方法では、セラミックス基体
２１とシース２５とは接着用ガラス２６を介して接着・
固定されており、接着用ガラス２６の安定性、密着性の
不良や熱接触抵抗の問題により、セラミックスヒーター
の温度を正確かつ安定に測定することができず、セラミ
ックスヒーターの安定した温度制御をすることができな
い問題があった。また、接着用ガラス２６の代わりに、
カーボン接着剤や無機接着剤等の他の材料を使用するこ
ともできるが、やはり同様の問題があった。However, in the conventional thermocouple mounting method shown in FIG. 6, the ceramic base 21 and the sheath 25 are bonded and bonded via the bonding glass 26.
The temperature of the ceramic heater cannot be measured accurately and stably due to the stability of the bonding glass 26, the poor adhesion and the problem of thermal contact resistance. There was a problem that could not be done. Also, instead of the bonding glass 26,
Other materials such as carbon adhesives and inorganic adhesives can be used, but still suffer from similar problems.
【０００５】本発明の目的は上述した課題を解消して、
セラミックスヒーターの温度を正確かつ安定に測定する
ことのできる温度測定構造を有するセラミックスヒータ
ーを提供しようとするものである。An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a ceramic heater having a temperature measurement structure capable of accurately and stably measuring the temperature of the ceramic heater.
【０００６】[0006]
【課題を解決するための手段】本発明のセラミックスヒ
ーターは、セラミックス基体中に高融点金属からなる抵
抗発熱体を埋設してなるセラミックスヒーターにおい
て、前記セラミックス基体のウェハーを載置するウェハ
ー加熱面以外の面に雌ネジ部を設け、この雌ネジ部に、
熱電対自体の先端部に設けた雄ネジ部を螺合させて固定
したことを特徴とするものである。また、本発明のセラ
ミックスヒーターは、セラミックス基体中に高融点金属
からなる抵抗発熱体を埋設してなるセラミックスヒータ
ーにおいて、前記セラミックス基体のウェハーを載置す
るウェハー加熱面以外の面に塊状埋設体を埋設し、この
塊状埋設体に雌ネジ部を設け、この雌ネジ部に、熱電対
自体の先端部に設けた雄ネジ部を螺合させて固定したこ
とを特徴とするものである。According to the present invention, there is provided a ceramic heater in which a resistance heating element made of a high melting point metal is embedded in a ceramic substrate, except for a wafer heating surface on which a wafer of the ceramic substrate is mounted. The female screw part is provided on the surface of
It is characterized in that a male screw portion provided at the tip of the thermocouple itself is screwed and fixed. Further, the ceramic heater of the present invention is a ceramic heater in which a resistance heating element made of a high melting point metal is embedded in a ceramic substrate, wherein a massive embedded body is formed on a surface other than a wafer heating surface on which a wafer of the ceramic substrate is mounted. The mass buried body is provided with a female screw portion, and a male screw portion provided at the tip of the thermocouple itself is screwed and fixed to the female screw portion.
【０００７】[0007]
【作用】上述した構成において、熱電対をセラミックス
基体にネジ止めして固定しているため、熱電対とセラミ
ックス基体との直接接触する面積が従来の例と比べて大
きくなり、その結果セラミックスヒーター自体の温度を
正確に測定することができる。また、熱電対とセラミッ
クス基体との固定をネジ止めにより行っているため、温
度測定時の接触状態が変化しにくく、セラミックスヒー
ターの温度を安定して測定することができる。In the above construction, since the thermocouple is fixed to the ceramic base by screwing, the area of direct contact between the thermocouple and the ceramic base is larger than that of the conventional example, and as a result, the ceramic heater itself is formed. Temperature can be accurately measured. In addition, since the thermocouple and the ceramic base are fixed by screws, the contact state at the time of temperature measurement hardly changes, and the temperature of the ceramic heater can be stably measured.
【０００８】[0008]
【実施例】図１は本発明のセラミックスヒーターの一例
の構成を示す図である。図１に示す実施例において、１
は窒化珪素等のセラミックスよりなる円盤状のセラミッ
クス基体、２はセラミックス基体１中に埋設したＷ、Ｍ
ｏ等の高融点金属よりなる抵抗発熱体である。この抵抗
発熱体２は好ましくは螺旋状に巻回されるとともに、円
盤状のセラミックス基体２を平面的にみると、抵抗発熱
体２は渦巻形をなすように配置されている。また、セラ
ミックス基体１のウェハー加熱面１ａ以外の面、図１に
示す例ではセラミックス基体１のウェハー加熱面１ａと
反対側の面に、深さｌの雌ネジ部３を設けている。そし
て、先端部にこの雌ネジ部３と螺合する雄ネジ部４を有
するシース５を準備し、シース５の内部に熱電対６を固
定した状態で、シース５の雄ネジ部４とセラミックス基
体１のネジ部３とを螺合して、熱電対６を内部に固定し
たシース５をセラミックス基体１に固定している。FIG. 1 is a view showing the structure of an example of a ceramic heater according to the present invention. In the embodiment shown in FIG.
Is a disk-shaped ceramic substrate made of ceramics such as silicon nitride, and 2 is W, M embedded in the ceramic substrate 1.
It is a resistance heating element made of a high melting point metal such as o. The resistance heating element 2 is preferably spirally wound, and the resistance heating element 2 is arranged so as to form a spiral when the disc-shaped ceramic base 2 is viewed in plan. In addition, on the surface of the ceramic substrate 1 other than the wafer heating surface 1a, in the example shown in FIG. 1, a female screw portion 3 having a depth 1 is provided on the surface of the ceramic substrate 1 opposite to the wafer heating surface 1a. Then, a sheath 5 having an external thread portion 4 screwed to the internal thread portion 3 at the distal end is prepared, and the external thread portion 4 of the sheath 5 and the ceramic base are fixed with the thermocouple 6 fixed inside the sheath 5. The sheath 5 in which the thermocouple 6 is fixed inside is fixed to the ceramic base 1 by screwing the screw portion 3 of the ceramic substrate 1.
【０００９】ここで、図２に示すネジの公式に従って、
ネジ部を設けたことによる接触面積の増大について考え
てみると、Ｍ３のネジで図１に示す深さｌが１０ｍｍの
場合を考えてみると、ピッチがＰ＝０．３５でネジ山は
２８．６個となる。ネジ山一個の接触面積を断面の距離
として求めると２×（Ｈ１／ｃｏｓ３０゜）となり、こ
の２８．６倍が断面の接触距離となる。従って、深さｌ
＝１０ｍｍに対する断面の接触距離ＬはＬ＝２×（０．
５４×０．３５／０．８７）×２８．６＝１２．５ｍｍ
となり、接触面積は約１．２５倍となる。また、Ｍ５の
ネジで同様の条件でピッチがＰ＝０．５のときを考える
と、断面の接触面積はＬ＝２×（０．５４×０．５／ｃ
ｏｓ３０゜）×２０＝１２．５ｍｍとなり、同様に接触
面積が約１．２５倍となる。Here, according to the screw formula shown in FIG.
Considering the increase in the contact area due to the provision of the thread portion, considering the case where the depth l shown in FIG. 1 is 10 mm with the M3 screw, the pitch is P = 0.35 and the thread is 28. .6. If the contact area of one screw thread is calculated as the distance of the cross section, it becomes 2 × (H1 / cos30 °), and 28.6 times this is the contact distance of the cross section. Therefore, the depth l
= 10 mm, the contact distance L of the cross section is L = 2 x (0.
54 × 0.35 / 0.87) × 28.6 = 12.5 mm
And the contact area becomes about 1.25 times. Considering the case where the pitch is P = 0.5 under the same conditions with an M5 screw, the contact area of the cross section is L = 2 × (0.54 × 0.5 / c).
os30 ゜) × 20 = 12.5 mm, and the contact area becomes about 1.25 times as well.
【００１０】図３は本発明のセラミックスヒーターの他
の例の構成を示す図である。図３に示す例において、図
１に示す例と同一の部材には同一の符号を付し、その説
明を省略する。図３に示す例において、図１に示す例と
異なるのは、熱電対自体を直接セラミックス基体にネジ
止め固定した点である。すなわち、熱電対６を、一対の
リード線１１ａ、１１ｂと金属製の先端部１２とから構
成し、リード線１１ａ、１１ｂを先端部１２に溶接する
とともに、先端部１２の外周に雄ネジ部４を形成し、セ
ラミックス基体１に形成した雌ネジ部３と螺合して固定
している。先端部１２の材質としては、高温でも使用で
きる点からＰｔを使用することが好ましい。図３に示す
例では、図１に示す例と比較して、先端部１２がバルク
形状であり熱容量が大であるため、、温度の変動が少な
くできさらに安定してセラミックスヒーターの温度を測
定することができる。FIG. 3 is a view showing the structure of another example of the ceramic heater according to the present invention. In the example shown in FIG. 3, the same members as those in the example shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The example shown in FIG. 3 differs from the example shown in FIG. 1 in that the thermocouple itself is directly screwed and fixed to the ceramic base. That is, the thermocouple 6 is composed of a pair of lead wires 11 a and 11 b and a metal tip 12, and the leads 11 a and 11 b are welded to the tip 12 and a male screw 4 Is formed and screwed and fixed to the female screw portion 3 formed on the ceramic base 1. It is preferable to use Pt as the material of the tip portion 12 because it can be used even at high temperatures. In the example shown in FIG. 3, the temperature of the ceramic heater can be measured more stably since the tip 12 has a bulk shape and a large heat capacity as compared with the example shown in FIG. be able to.
【００１１】図４は本発明のセラミックスヒーターのさ
らに他の例の構成を示す図である。図４に示す例におい
ては、セラミックス基体３１に、抵抗発熱体３２を埋設
するとともに、金属またはセラミックスからなる塊状埋
設体３４を一体となして、この塊状埋設体３４に雌ネジ
部３６を設け、熱電対先端３５をネジ込み固定してい
る。また、熱電対先端３５より、リード線３３ａ，３３
ｂを取り出している。図４に示す構造のメリットは、塊
状埋設体３４を加工しやすい材質（例えばＷ、Ｍｏ、Ｓ
ｉＣ）にすることによって、安価なセラミックスヒータ
ーを提供できることである。FIG. 4 is a view showing the structure of still another example of the ceramic heater according to the present invention. In the example shown in FIG. 4, a resistance heating element 32 is embedded in a ceramic base 31, and a massive embedded body 34 made of metal or ceramics is integrally formed, and a female screw portion 36 is provided in the massive embedded body 34. The thermocouple tip 35 is screwed and fixed. Also, lead wires 33a, 33
b is taken out. The advantage of the structure shown in FIG. 4 is that materials (eg, W, Mo, S
By using iC), an inexpensive ceramic heater can be provided.
【００１２】図５は本発明のセラミックスヒーターのさ
らに他の例の構成を示す図である。図５に示す例におい
ては、熱電対先端４４とセラミックス基材４１との間に
インサート金具４７を入れ、外周の雄ネジ部４５にてセ
ラミックス基体４１と結合するとともに、内周の雌ネジ
部４６にて熱電対先端４４と結合している。また、熱電
対先端４４より、リード線４３ａ，４３ｂを取り出して
いる。図５に示す構造のメリットは、セラミックスから
なる基体４１に小さな雌ネジの加工は困難であるため
に、一回り大きなネジとすることが可能であり、安価な
セラミックスヒーターを提供できることである。FIG. 5 is a view showing the structure of still another example of the ceramic heater of the present invention. In the example shown in FIG. 5, an insert fitting 47 is inserted between the thermocouple tip 44 and the ceramic base material 41, and is connected to the ceramic base 41 at the outer male screw part 45 on the outer circumference, and the inner female screw part 46 on the inner circumference is provided. At the thermocouple tip 44. Further, lead wires 43a and 43b are taken out from the thermocouple tip 44. An advantage of the structure shown in FIG. 5 is that, since it is difficult to form a small female screw on the base body 41 made of ceramics, it is possible to use a slightly larger screw and provide an inexpensive ceramic heater.
【００１３】本発明は上述した実施例にのみ限定される
ものではなく、幾多の変形、変更が可能である。例え
ば、上述した実施例では、ネジ部をセラミックス基体１
のウェハー加熱面１ａの反対側に設けたが、この位置は
ウェハー加熱面１ａ以外の面であればどこでも良く、例
えば側面にネジ部を設けても同様の効果を得ることがで
きることは明かである。また、ネジ部の径および深さも
上述した実施例に限定されるものではなく、セラミック
ス基体の大きさ等に応じて適宜選べば良いことはいうま
でもない。The present invention is not limited to the above-described embodiment, but can be variously modified and changed. For example, in the above-described embodiment, the screw portion is connected to the ceramic base 1.
Is provided on the opposite side of the wafer heating surface 1a, but it is clear that this position may be any position other than the wafer heating surface 1a. For example, it is apparent that the same effect can be obtained by providing a screw portion on the side surface. . Further, the diameter and depth of the thread portion are not limited to those in the above-described embodiment, and it goes without saying that the thread portion may be appropriately selected according to the size of the ceramic base.
【００１４】[0014]
【発明の効果】以上の説明から明かなように、本発明に
よれば、熱電対をセラミックス基体にネジ止めして固定
しているため、熱電対とセラミックス基体との直接接触
する面積が従来の例と比べて大きくなり、その結果セラ
ミックスヒーター自体の温度を正確に測定することがで
きるとともに、熱電対とセラミックス基体との固定をネ
ジ止めにより行っているため、温度測定時の接触状態が
変化しにくく、セラミックスヒーターの温度を安定して
測定することができる。As is clear from the above description, according to the present invention, since the thermocouple is fixed to the ceramic base by screwing, the area of direct contact between the thermocouple and the ceramic base is reduced. As a result, the temperature of the ceramic heater itself can be measured accurately, and since the thermocouple and the ceramic base are fixed by screws, the contact state during temperature measurement changes. It is difficult to measure the temperature of the ceramic heater stably.
【図１】本発明のセラミックスヒーターの一例の構成を
示す図である。FIG. 1 is a diagram showing a configuration of an example of a ceramic heater according to the present invention.
【図２】本発明のネジ部により接触面積が増大する例を
説明するための図である。FIG. 2 is a diagram for explaining an example in which a contact area is increased by a screw portion according to the present invention.
【図３】本発明のセラミックスヒーターの他の例の構成
を示す図である。FIG. 3 is a diagram showing a configuration of another example of the ceramic heater of the present invention.
【図４】本発明のセラミックスヒーターのさらに他の例
の構成を示す図である。FIG. 4 is a view showing a configuration of still another example of the ceramic heater of the present invention.
【図５】本発明のセラミックスヒーターのさらに他の例
の構成を示す図である。FIG. 5 is a view showing a configuration of still another example of the ceramic heater of the present invention.
【図６】従来のセラミックスヒーターの一例の構成を示
す図である。FIG. 6 is a diagram showing a configuration of an example of a conventional ceramic heater.
１ セラミックス基体 １ａ ウェハー加熱面 ２ 抵抗発熱体 ３ 雌ネジ部 ４ 雄ネジ部 ５ シース ６ 熱電対 DESCRIPTION OF SYMBOLS 1 Ceramic base 1a Wafer heating surface 2 Resistance heating element 3 Female screw part 4 Male screw part 5 Sheath 6 Thermocouple
Claims (2)
抵抗発熱体を埋設してなるセラミックスヒーターにおい
て、前記セラミックス基体のウェハーを載置するウェハ
ー加熱面以外の面に雌ネジ部を設け、この雌ネジ部に、
熱電対自体の先端部に設けた雄ネジ部を螺合させて固定
したことを特徴とするセラミックスヒーター。1. A ceramic heater having a resistance heating element made of a high melting point metal embedded in a ceramic substrate, wherein a female screw portion is provided on a surface of the ceramic substrate other than a wafer heating surface on which a wafer is mounted. In the screw part,
A ceramic heater characterized in that a male screw portion provided at the tip of the thermocouple itself is screwed and fixed.
抵抗発熱体を埋設してなるセラミックスヒーターにおい
て、前記セラミックス基体のウェハーを載置するウェハ
ー加熱面以外の面に塊状埋設体を埋設し、この塊状埋設
体に雌ネジ部を設け、この雌ネジ部に、熱電対自体の先
端部に設けた雄ネジ部を螺合させて固定したことを特徴
とするセラミックスヒーター。2. A ceramic heater in which a resistance heating element made of a high melting point metal is embedded in a ceramic substrate, wherein a massive embedded body is embedded on a surface other than a wafer heating surface on which a wafer of the ceramic substrate is mounted. A ceramic heater characterized in that a female screw portion is provided in a massive buried body, and a male screw portion provided at the tip of the thermocouple itself is screwed to the female screw portion and fixed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4321921A JP2644660B2 (en) | 1992-12-01 | 1992-12-01 | Ceramic heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4321921A JP2644660B2 (en) | 1992-12-01 | 1992-12-01 | Ceramic heater |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06176855A JPH06176855A (en) | 1994-06-24 |
| JP2644660B2 true JP2644660B2 (en) | 1997-08-25 |
Family
ID=18137901
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4321921A Expired - Lifetime JP2644660B2 (en) | 1992-12-01 | 1992-12-01 | Ceramic heater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2644660B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7090394B2 (en) | 2002-10-08 | 2006-08-15 | Sumitomo Electric Industries, Ltd. | Temperature gauge and ceramic susceptor in which it is utilized |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59171989A (en) * | 1983-03-18 | 1984-09-28 | 株式会社東芝 | Extra character display control system |
| JPH07104212B2 (en) * | 1990-07-27 | 1995-11-13 | 日本碍子株式会社 | Heating device and manufacturing method thereof |
-
1992
- 1992-12-01 JP JP4321921A patent/JP2644660B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7090394B2 (en) | 2002-10-08 | 2006-08-15 | Sumitomo Electric Industries, Ltd. | Temperature gauge and ceramic susceptor in which it is utilized |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06176855A (en) | 1994-06-24 |
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