Wafer heating apparatus

• US 6,753,507 B2
• Filed: 04/26/2002
• Issued: 06/22/2004
• Est. Priority Date: 04/27/2001
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Fure, Hiroshi, Uchiyama, Kyoji, Nagasaki, Koichi
• Primary Examiner(s): FUQUA, SHAWNTINA T
• Application Number:
  US10/134,294
• Publication Number:
  US 20030015517A1
• Time in Patent Office: 788 Days
• Field of Search: 219/444.1, 219/465.1, 219/466.1, 219/467.1, 219/543, 219/544, 219/546, 219/547, 219/548, 118/724, 118/725, 118/728
• US Class Current: 219/444.1
• CPC Class Codes: H01L 21/67103 mainly by conduction
• CPC Class Codes: H05B 3/143 applied to semiconductors, e.g. wafers heating H05B3/0047 takes precedence
• CPC Class Codes: H05B 3/265 the insulating base being an inorganic material, e.g. ceramic H05B3/262 takes precedence

Abstract

In a ceramic heater having a plate-like body made of a ceramic, heating element in one main face of the plate like body, and an electric supply portion to be electrically connected with the heating element, it has been a problem that the temperature is uneven if bent portions are formed in heat generating patterns. The ceramic heater simultaneously satisfying the following: 0.15≦S≦0.85, 0.3≦P≦6.71×S²+1.52, and 0.3≦G≦6.71×(1−S)²+1.55, in which the reference character S1 denotes the surface area of the heating element in optional 10 mm square region of the effective heat generation area having the heating element therein; the surface ratio S denotes S=S1/100 mm², the reference character P denotes the width of the heating element: and the reference character G denotes the gap between the heating element.

Claims

1. A wafer heating apparatus comprising:

a heat homogenizing plate of a ceramic having one main face for mounting a wafer;

a heating element composed of a plurality of resister strips which are attached on other main surface or inside thereof; and

electric supply portions electrically connected with the plurality of the resistor strips of the heating element;

wherein the heating element satisfies the following relations;

2. The wafer heating apparatus according to claim 1, wherein the heat homogenizing plate has a thickness of 1 to 8 mm.

3. The wafer heating apparatus according to claim 1, wherein the outer diameter of the circular heating element is within a range of 1.02 to 1.20 times as large as that of the wafer to be mounted on the heat homogenizing plate.

4. The wafer heating apparatus according to claim 1, wherein the temperature coefficient of resistance of the resister strips is 3,000×

10<sup>−

6</sup>/°

C. or less.

5. The wafer heating apparatus according to claim 1, wherein the resister strips of the heating element are partially trimmed for controlling the heating amount.

6. A wafer heating apparatus comprising:

a heat homogenizing plate of a ceramic having one main face for mounting a wafer;

a heating element composed of a plurality of resister strips which are attached on other main surface or inside thereof;

electric supply portions electrically connected with the plurality of the resistor strips of the heating element; and

a casing for supporting the heat homogenizing thereon

wherein said heating element satisfies the following relations;

7. The wafer heating apparatus according to claim 6, wherein the distance between the inner edge of the plate holding part, for holding the heat homogenizing plate, of the casing and the outer edge of the circular heating element is set to be 2 mm or more;

and

the outer diameter of said heating element is set wider than the outer diameter of a wafer by 5 mm or more.

8. The wafer heating apparatus according to claim 6, wherein the outer diameter of the circular heating element is within a range from 1.075 to 1.30 times as large as that of a wafer to be mounted.

9. A wafer heating apparatus comprising:

a heat homogenizing plate of a ceramic having one main face for mounting a wafer;

a heating element composed of a plurality of resister strips which are attached on other main surface or inside thereof; and

electric supply portions electrically connected with the plurality of the resistor strips of the heating element, wherein the heat homogenizing plate has a plurality of supporting pins thereon for supporting the wafer over the mounting surface; and

the heat homogenizing plate has emissivity ε

of 0.8 or higher with respect to infrared rays of wavelength λ

of 8 μ

m at 100°

C. or higher.

10. The wafer heating apparatus according to claim 9, wherein the supporting pins have projection heights of 0.05 to 0.5 mm on the bases of the one main face for mounting the wafer.

11. The wafer heating apparatus according to claim 9, wherein the diameter of the supporting pins is 2 to 10 mm and the contact surface area of the supporting pins with a wafer is 10 mm² or less each supporting pin.