A Chemical/Microwave Technique for the Measurement of Bulk Minority Carrier Lifetime in Silicon Wafers

Abstract

A chemical/microwave technique for the measurement of bulk minority carrier lifetime in silicon wafers is described. This method consists of a wet chemical treatment (surface cleaning, oxidation in solution, and measurement in solution) to passivate the silicon surfaces, a laser diode array for carrier excitation, and a microwave bridge measuring system which is more sensitive than the microwave systems used previously for lifetime measurement. Representative experimental data are presented to demonstrate this technique. The result reveals that this method is useful for the determination of bulk lifetime of commercial silicon wafers.