Effect of Auger recombination induced by donor and acceptor states on luminescence properties of silicon quantum Dots/SiO₂ multilayers

Impurity doping is a key factor that needs to be addressed to control the optical properties of silicon quantum dots (Si QDs) for their applications in optoelectronic devices. Although there have been several studies to understand the effect on n-type and p-type dopant on the luminescence properties of Si QDs, the exact influence of the dopant impurities on the optical properties and the underlying mechanism are yet to be understood. For this purpose, we investigate the luminescence properties of Si QDs/SiO₂ multilayer structure doped with B and P. Using rf-magnetron sputtering and ion implantation techniques, we prepared three kinds of samples: undoped, B-doped and P-doped. Results from photoluminescence measurements indicate that the significant luminescence suppression in the doped samples can be mainly attributed to the Auger non-radiative process occurring between photoexcited excitons and free carriers. Our interpretation should serve to resolve the controversy around the effect of impurity doping on the luminescence properties of Si QDs.