The Effect of Doping Concentrations on the Thickness of the Depletion Layer on Some Semiconductor Materials

Abstract

In this work, the code “Poisson” written by Silsbee and Drager, developed at Cornell University was used to Simulate band bending and carrier concentrations in the inhomogenous semiconductors: Gallium nitride, Zinc oxide, Cadmium sulfide, Cadmium selenide, Cadmium telluride, Indium phosphide, Gallium arsenide and Silicon. The energy gap for these semiconductors is generally greater than 1eV. Simulation of doping concentrations was run on preset four (4) on the code “Poisson”. The effect of doping concentrations on the thickness of the depletion layer width and charge displacement of the semiconductor materials was obtained. The width of depletion layer decreases with increase in doping concentrations while increase in doping concentrations leads to increase in the charge displacement. The relationship between depletion layer width and the doping concentrations (from 1×10²⁰ to 1×10¹⁶ cm^-3 )   is best described by a power function of the form y=ax^b. On the other hand, wide band gap results in increase in depletion layer width.