Journal of Vacuum Science & Technology B, Vol.16, No.2, 613-618, 1998
Comparative study of back surface field contact formation using different lamp configurations in rapid thermal processing
In this article, we have studied the role of photoeffects in the formation of aluminum back surface field (BSF) contacts on p-type silicon wafers by using different lamp configurations in rapid thermal processing (RTP). Use of photons of wavelengths less than 800 nm in conjunction with infrared and visible photons in RTP resulted in the reduction of processing time from 202 to 138 s and the processing temperature from 890 to 850 degrees C. The reduction in the overall thermal budget used for BSF contact formation is a direct result of photon assisted RTP. The availability of a large number of high energy photons on the metal surface also resulted in improved electrical, structural and mechanical properties of the processed device.