氢间隙杂质对CdTe材料电子结构的影响：第一性原理研究

he structural and electronic properties of the interstitial hydrogen impurity in CdTe have been studied by plane-wave pseudopotential method based on the density functional theory. Structural relaxation, density of states(DOS), electron localization function(ELF), bonding-charge density and ionizing-charge density have been computed to investigate the effects of the interstitial hydrogen on the electronic structure and bonding mechanism of CdTe. The results of formation energy indicate that H prefers to occupying the tetrahedral interstitial site and bonding to a host atom. Obvious relaxations occur around monatomic hydrogen. As for the anion tetrahedral interstitial, hydrogen tends to break the bond between TeH(adsorbed by H) and Cdop(opposite Cd). Meanwhile, the interstitial hydrogen behaves an amphoteric impurity. The self-compensating effect of interstitial hydrogen impurity pins the Fermi level just above the mid-gap.