Post-Doping of Si Quantum-Dot Thin Films with Phosphorus via a Spin-on-Dopant Process for Photovoltaic Applications

High Resolution Image Download MS PowerPoint Slide In this report, we propose a post-doping process for silicon quantum-dot (Si QD) thin films that preserves their crystallinity while enhancing their electrical and optical properties. The process primarily involves a spin-on-dopant (SOD) technique, whereby a mixture of phosphorus pentoxide and silicon dioxide solutions is coated onto the Si QD thin film followed by a crucial diffusion process. Across various doping levels, the Si QD thin films exhibit a uniformly high crystallinity and substantial light absorption. By optimization of the P 2 O 5 concentration in the dopant solution and diffusion conditions of phosphorus atoms within the Si QD thin films, a high photovoltaic conversion efficiency of approximately 11.68% is achieved. These results strongly demonstrate the feasibility of doping Si QD thin films through a simple and cost-effective SOD process and highlight their potential for photovoltaic applications based on Si QD thin films.