Computer solution of depletion and accumulation layers and analysis of abrupt n - n heterojunctions

Abstract

The digital computer solutions of depletion and accumulation layers are given for doping levels of 10¹⁴, 10¹⁵ and 10¹⁶ cm⁻³ using Ehrenberg's approximation. The interface values of voltage against electric field are plotted and the depletion layer solutions are compared with the parabolic approximation, which is found to give only about 1% error for calculation of interface values although it is not so good for obtaining the actual barrier shape. A new technique is presented for analysing abrupt n-n heterojunctions and the (C, V) characteristic is analysed in detail. The plot of C⁻² against V is in fact linear, in reverse bias only, although the simple formula C²=(eN_d)/2(V_d-V) is not applicable.