Electronic structure of divacancy–hydrogen complexes in silicon

Abstract

Divacancy–hydrogen complexes(V2H andV2H2)in Si are studied by ab initio modelling using large supercells. Here we payspecial attention to their electronic structure, showing that these defectsproduce deep carrier traps. Calculated electrical gap levels indicate thatV2H2 is an acceptor,whereas V2H is amphoteric, with levels close to those of the well known divacancy. Finally our results arecompared with the available data from deep level transient spectroscopy and electronparamagnetic resonance experiments.