A Simple Graphical Method for Determining Densities and Energy Levels of Donors and Acceptors in Semiconductor from Temperature Dependence of Majority Carrier Concentration

Abstract

The purpose of this study is to propose a simple graphical method for accurately determining the densities and energy levels of donors and acceptors with different energy levels in a semiconductor from the temperature dependence of majority carrier concentration n(T). For this purpose, a function S(T,E ref) is defined as S(T,E ref) ≡n(T) exp (E ref/kT) /kT, where k is the Boltzmann constant and E ref is a parameter which varies a peak temperature of S(T,E ref). Since S(T,E ref) has peaks corresponding to the energy levels of impurities which produce majority carriers, the density and energy level can be evaluated using each peak in the S(T,E ref) curve. This method can be used to investigate how many kinds of impurities, which produce majority carriers, exist in a semiconductor. Moreover, the density of all impurities, which produce minority carriers, can be determined, since we can simulate the dependence of S(T,E ref) on this density.