HEAT TREATMENT METHOD AND HEAT TREATMENT APPARATUS FOR HEATING SUBSTRATE BY IRRADIATING SUBSTRATE WITH LIGHT

• US 20120288261A1
• Filed: 05/10/2012
• Published: 11/15/2012
• Est. Priority Date: 05/13/2011
• Status: Active Grant

• Current Assignee: SCREEN Holdings Co., Ltd.
• Original Assignee: SCREEN Holdings Co., Ltd.
• Inventors: HASHIMOTO, Kazuyuki, KUSUDA, Tatsufumi
• Granted Patent: US 9,920,993 B2
• Time in Patent Office: Days
• US Class Current: 392/416
• CPC Class Codes: F27B 17/0025 Especially adapted for treating semiconductor wafers
• CPC Class Codes: F27D 5/0037 Supports specially adapted for semi-conductors
• CPC Class Codes: H01L 21/67115 mainly by radiation
• CPC Class Codes: H01L 21/67248 Temperature monitoring

Abstract

A photodetector element for receiving radiated light from a surface of a semiconductor wafer loses a detection function because the intensity of the received light exceeds a detection limit while a flash lamp emits light. Measurement is not performed during the above-mentioned period, and the intensity of the radiated light from the surface of the semiconductor wafer is measured after the flash lamp stops emitting light and the photodetector element restores the detection function. Then, the temperature of the surface of the semiconductor wafer heated by irradiation with a flash of light is calculated based on the measured intensity of the radiated light. Accordingly, even in a case where intense irradiation is performed in an extremely short period of time, such as flash irradiation, the flash of light does not act as ambient light, which enables to obtain the surface temperature of the semiconductor wafer.

Claims

1. A heat treatment apparatus for heating a substrate by irradiating the substrate with light, comprising:

a chamber for receiving a substrate therein;

a holder for holding the substrate within said chamber;

an irradiation part for irradiating a surface of the substrate held by said holder with light;

a photodetector element provided on the surface side of the substrate held by said holder, for receiving radiated light from said surface;

a radiated light intensity measuring part for measuring an intensity of the radiated light received by said photodetector element; and

a temperature calculating part for calculating a temperature of the surface of said substrate heated by said irradiation based on the intensity of the radiated light from the surface of said substrate, the intensity being measured by said radiated light intensity measuring part after said irradiation part stops irradiation.

2. The heat treatment apparatus according to claim 1, wherein

said temperature calculating part calculates the temperature of the surface of said substrate based on a plurality of intensities of radiated light, the intensities being measured in chronological order by said radiated light intensity measuring part after said irradiation part stops irradiation.

3. The heat treatment apparatus according to claim 2, wherein

said temperature calculating part obtains an approximate expression indicating changes in time of the intensity of the radiated light from said plurality of intensities of radiated light, to thereby calculate the temperature of the surface of said substrate from said approximate expression.

4. The heat treatment apparatus according to claim 1, wherein

said irradiation part comprises a flash lamp for irradiating the substrate with a flash of light.

5. The heat treatment apparatus according to claim 4, wherein

said photodetector element comprises an indium antimonide radiation thermometer.

6. A method of heating a substrate by irradiating the substrate with light, comprising the steps of:

(a) irradiating the substrate with light;

(b) measuring an intensity of radiated light from a surface of said substrate after the irradiation in said step (a) is stopped; and

(c) calculating a temperature of the surface of said substrate heated in said step (a) based on the intensity of the radiated light from the surface of said substrate, the intensity being measured in said step (b).

7. The method according to claim 6, wherein

in said step (b), a plurality of intensities of the radiated light from the surface of said substrate are measured in chronological order after the irradiation in said step (a) is stopped, and

in said step (c), the temperature of the surface of said substrate is calculated based on said plurality of intensities of the radiated light measured in chronological order in said step (b).

8. The method according to claim 7, wherein

in said step (c), an approximate expression indicating changes in time of the intensity of the radiated light is obtained from said plurality of intensities of the radiated light, to thereby calculate the temperature of the surface of said substrate from said approximate expression.

9. The method according to claim 6, wherein

in said step (a), the substrate is irradiated with a flash of light from a flash lamp.