Precision of Non-invasive Temperature Measurement by Diffuse Reflectance Spectroscopy

Abstract

We demonstrate the use of diffuse reflectance spectroscopy as a non-invasive probe for measurement of temperature in real time on Si and GaAs substrates during semiconductor processing. Our results show that the standard deviation of the non-invasive optical technique is less than 0.7 'C for GaAs over the temperature range 50 OC < T< 600 °C with 5-second updates. These results support the notion that non-invasive optical temperature measurement can be used in semiconductor processing with a precision exceeding that of a thermocouple.INTRODUCTION:

Monitoring and Control in Vapor phase Epitaxy

“…Some of the technology areas where process control can be expected to have an important impact are: temperature measurement, flux measurement both for chemical composition and concentration, growth / etch rates, surface composition, and particle detection. [2][3] …”