Comparative Study of HgCdTe Etchants: An Electrical Characterization

Abstract

A comparative study of wet etchants for both molecular beam epitaxy (MBE) and liquid phase epitaxy (LPE) grown n-and p-type samples was performed using capacitance-voltage (C-V) characteristics and surface recombination velocity (SRV) extracted from photoconductive decay (PCD) measurements. Different wet etchants were divided in two categories, (i) where bromine is a direct reagent in the etching solution and (ii) where bromine is a byproduct after reaction among different reagents. Negative shift of the flat-band voltages were observed for both n-and p-type samples treated with second category of etchants. A decrease in minority carrier lifetimes and an increase in the surface recombination velocities were also observed for the n-type samples treated with second category of etchants.