Effects of phosphorus doping on the optical and electronic properties of Si-quantum-dots/SiO2 multilayer films

• Phosphorus doped Si-quantum-dots/SiO2 films have been prepared.
• Carrier capture centers at the interface were filled by phosphorus doping.
• The optoelectronic properties of films were enhanced by proper doping.

Phosphorus (P) doped Si-quantum-dots/SiO2 multilayer films have been deposited by plasma enhanced chemical vapor deposition (PECVD) technique, and Si quantum dots (Si-QDs) are obtained by the following annealing treatment. Raman and transmission electron microscopy (TEM) results show that P doping prevents the growth of Si-QDs. The photoluminescence (PL) intensity can be enhanced by proper P doping, and a maximal PL intensity is obtained when the doping flow ratio of phosphine and silicane is 0.75%. The resistivity of the films is reduced by P doping, and proper doping leads two orders of magnitude lower than that of the intrinsic films. Analysis shows that proper P doping in the multilayer films could fill the carrier capture center in interface and suppress the non-radiative recombination of carriers.