DEEP LEVELS PARAMETERS DETERMINATION IN THE SEMICONDUCTOR BAND GAP BY THE ISOTHERMAL CAPACITY RELAXATION METHOD

Abstract

Deep levels parameters determination by isothermal capacity relaxation in our methodology
is based on three stages of numerical analysis. Firstly we need to carry out a regression analysis
of isothermal capacity relaxation characteristics. The modeling exercise results motivate to carry out
a correlation-cluster analysis of set of points in Arrhenius coordinates. A consistent application of
these two stages provides an opportunity to automatically determine the deep level parameters.
However, applying algorithms are not pure analytic. The third stage uses mathematical statistics and
cluster analysis methods to estimate the validity of obtained deep level parameters. Experimental
investigation of deep levels energies spectrums in n-type gallium arsenide band gap was carried out.
As an important result it should be noted that our method possesses much better resolving power in
comparison with the standard DLTS-method. We can make a conclusion that our method allow to
determine the deep level capture cross sections more precisely in comparison with standard
DLTS-method, especially for deep levels located in the middle of semiconductor band gap. Also one
of the advantages of the method under consideration consists in its almost full automatization.