Measurement of nonequilibrium carrier recombination lifetime in silicon wafers by noncontact microwave technique

摘要

A setup and a noncontact microwave technique for photoconductance relaxation measurement under pulsed illumination of a high-resistance silicon wafer are briefly described. Formulas for calculation of the reflectance and sensitivity in microwave photoconductance relaxation measurement are presented. It is shown that for some combination of the wafer conductance and thickness the sensitivity is zero. Results on microwave lifetime measurement(f = 9.4GHz) for silicon wafers 10 and 0.4 mm thick for different surface recombination velocities are given.