EXAFS studies of novel impulsive hardening in the Be–Zn–Se semiconductor alloys

Abstract

Beryllium doping has been used to harden the inherently soft zinc-selenides semiconductor mixed alloys. Stoichiometric semiconductor ternary alloys of BexZn1-xSe have been synthesized by the Bridgeman technique. Extended X-ray absorption fine structure (EXAFS) spectroscopy — in a state-of-art synchrotron-based method — is performed by varying the dopant Be concentration of Be from 6% to 55% in the zinc–selenide host semiconductor. EXAFS analyses is carried out to study the next neighbor and next nearest neighbor atomic positions, nature of the substitutional doping, extent of bond length homogeneity, presence of involuntary contrast among the path distances, and the cross over from soft to hard character of the ternary on increasing Be concentration. Our results indicate the presence of an impulsive nature of hardening in the ternary with a disparity at the lower and the higher doping levels. The observation of impulsive hardening of the substitutional dopants in the semiconductor lattice is explained by the help of self-accommodative attributes of the host lattice.