Comparison of Minority Carrier Lifetimes Measured by Photoconductive Decay and ac Photovoltaic Method

Abstract

Minority carrier lifetimes measured by both ac photovoltaic and photoconductive decay methods are compared. The calculated results indicate that the maximum measurable lifetime for the ac photovoltaic method is about 7 times larger than that for the photoconductive decay method when surface recombination velocity is assumed to be infinite. The lifetimes for both p-type and n-type silicon rectangular samples measured by the ac photovoltaic method are in good agreement with the lifetimes ranging from 90 µs to 1 ms measured by the photoconductive decay method standardized by the Japanese Industrial Standard Committee. However, lifetimes measured by a noncontact photoconductive decay method using microwaves are far shorter than those measured by the above two methods.