Light-induced degradation in n-type Czochralski silicon by boron-doping and thermal donor compensation

Abstract

In this paper, the behaviors of boron-oxygen complexes related to the light-induced degradation (LID) have been studied in n-type boron-doped Czochralski silicon (Cz-Si) with different levels of thermal donors (TDs) compensation. The degradation is found to have two stages, a fast- and a slow-process, similar to that in p-type boron-doped Cz-Si. In order to compare with the properties of LID in p-type Si, we systematically investigate the dependence of the saturated defect concentration (Nt*) and the defect generation rate constant (Rgen) in our TD-compensated n-type Cz-Si on the carrier concentrations, i.e., the net electron concentration (n0) and the excess hole concentration (Δp). Moreover, we determine the activation energy for the slow-process to be 0.4 eV. Based on our results, we suggest that the LID effect in boron-doped Si, either in p-type case or in n-type case by compensation, should be attributed to the same defects.