Minority carrier life-time determination from steady state and transient response of a solar cell under illumination

Abstract

A comparative analysis is made of the different methods employed for determination of minority carrier life-time in the base and diffused layers of a p-n junction solar cell. Study of steady state response of the solar cell under monochromatic illumination yields the minority carrier diffusion length, from which the minority carrier life-time can be estimated. Study of transient response of the solar cell, with and without a light bias, and with carrier injection by an electrical pulse or an optical pulse, is made and then used for evaluation of open circuit transient voltage and minority carrier life-time. The transient voltage response of the solar cell leads to the familiar expression for the minority carrier life-time in terms of the slope of the curve, for open circuit voltage versus time. It is shown that there arc correction factors to the commonly used formula for life-time determination and it is expected that these will provide a better agreement between the life-time determination from the vari...