| 摘要 |
<P>PROBLEM TO BE SOLVED: To extend a temperature range of operation of a transmission pyrometer. <P>SOLUTION: A rapid thermal processing (RTP) system 110 includes a transmission pyrometer 12 for monitoring the temperature dependent absorption of a silicon wafer 32 for radiation from a RTP lamp 46 at a reduced power level. A look-up table is created relating unnormalized values of photodetector photocurrents with wafer and radiant lamp temperatures. A calibrating step measures the photocurrent with known wafer and lamp temperatures and all photocurrents measured thereafter are accordingly normalized. The transmission pyrometer may be used for closed loop control for thermal treatments below 500°C or used in a pre-heating phase for a higher temperature process including radiation pyrometry in the closed loop control. A pre-heating temperature ramp rate may be controlled by measuring an initial ramp rate and readjusting the lamp power accordingly. <P>COPYRIGHT: (C)2012,JPO&INPIT |
