Visible photoluminescence originated from various mechanisms during step-by-step annealing

Light emission variated from violet-blue to red-infrared is observed from a-Si:/SiO 2 multilayers during step by step annealing. The peak of photoluminescence (PL) changes in the range between 417nm and 750nm under excitation of 325nm light as a function of annealing temperature, which is strong enough to be observed by naked eyes. Combined with Fourier Transform Infrared (FTIR) measurements, the correlation of the red PL excited by 488nm Ar + laser and the structural evolution during the step by step annealing is detailed studied. The origins of different PL bands and the role of hydrogen and oxygen in microstructures of a-Si:/SiO 2 multilayers are discussed