Determination of the carrier lifetime from the open-circuit voltage decay of p-i-n rectifiers at high-injection levels

The method of finite elements has been used to determine the open-circuit voltage of p-i-n rectifiers at current turn-off from very high forward currents taking into account carrier-carder scattering, Auger recombination, and recombination in the end regions. It has been shown that the evaluation of the linear decay of the open-circuit voltage after Davies gives the true value of the carrier lifetime in the i-region only if the recombination in the end regions is negligible. Under the influence of the recombination in the end regions, the open-circuit voltage shows two linear decay ranges. The Davies formula gives a considerably smaller value for the lifetime, when the first linear decay of the open-circuit voltage is evaluated. However, the true value of the carrier lifetime can be determined, after Davies in the second linear range of the open-circuit voltage decay, with a high accuracy.