THE ABSORPTION AND CONDUCTIVITY FOR MICROSTRUCTURED SILICON IN THE IMPURITY-DEFECT MODEL

Abstract

In this paper, a model for the optical absorption and carrier concentration in microstructured silicon is presented based on Gaussian energy distribution of defect and impurity, as well as the Boltzmann distribution of carriers. The parameters of the impurity and defect model contributing to the absorption and carrier concentration are investigated. The simulation results show that the absorption in the single level impurity-defect model ranges from 64% to 68%; larger than that in the single level impurity model (55%–65%); as well as that in the defect model (50%–66%). It also indicates that the absorption increases with bigger correlation energy (U) and the best bandwidth (d) is 0.92 eV. However, the carrier concentration gets stronger with bigger bandwidth, smaller correlation energy and higher temperature. Thus, these calculations would play an important role in the applications of microstructured silicon.