NONEXPONENTIAL DEEP LEVEL TRANSIENT SPECTROSCOPY ANALYSIS OF MODERATELY DOPED BULK N-GAAS

A theoretical analysis is carried out of deep level transient spectra (DLTS) obtained on bulk moderately doped n-GaAs. The semiconductor is considered as a disordered one because fluctuations in the concentration of shallow donors and acceptors produce a random potential energy with a root-mean-square (RMS) fluctuation comparable to the mean thermal energy of the electrons. As a result, the energies of the deep levels obey a Gaussian distribution of the same RMS deviation. An original algorithm for the computer simulation of DLTS spectra is presented. The corrections to the peak energy and concentration of deep levels due to the random potential are estimated. Useful theoretical information about the microscopic parameters of the disordered system is presented as well. The degree of compensation of the material is determined.