Strong exciton energy blue shift in annealed Si/SiO2 single quantum wells

Abstract A theoretical study is presented on how the annealing-induced interfacial transition region changes the confined ground state exciton in Si/SiO2 single quantum wells (QWs). The interface thickness and the mean well width confinement depend on the time and temperature of annealing, as well as on the diffusion coefficient of oxygen in silicon. It is shown that an annealing-related interface width increase of a few Angstroms can strongly blue shift (hundreds of milli-electron volts) the confined ground state exciton energy in Si/SiO2 single quantum wells. The results allow to suggest that annealing processes can be used to tune (from red to blue) the light emission in Si/SiO2 single quantum wells.