Quenching of photoluminescence from Si nanocrystals caused by boron doping

Abstract

Boron-doped Si nanocrystals (nc-Si) as small as 2.7–3.8 nm in diameter were prepared and their photoluminescence (PL) properties were studied as functions of B concentration, size and excitation power. As the B concentration increased, the PL intensity decreased rapidly. The degree of PL quenching was found to increase with increasing size. In the case of undoped nc-Si, saturation and blue shift of PL peak were observed with increasing excitation power. However, these effects were not observed for heavily B-doped samples. The importance of the nonradiative Auger recombination process in B-doped nc-Si is discussed.