A First-Principle Study of B- and P-Doped Silicon Quantum Dots

Abstract

Doping of silicon quantum dots (Si QDs) is important for realizing the potential applications of Si QDs in the fields of Si QDs-based all-Si tandem solar cells, thin-film transistors, and optoelectronic devices. Based on the first-principle calculations, structural and electronic properties of hydrogen terminated Si QDs doped with single Boron (B) or phosphorus (P) are investigated. It is found out that the structural distortion induced by impurity doping is related to the impurity characteristic, impurity position, and the QD size according to the structural analysis. The relative energetic stability of Si QDs with a single impurity in different locations has been discussed, too Furthermore, our calculations of the band structure and electronic densities of state (DOS) associated with the considered Si QDs show that impurity doping will introduce impurity states within the energy gap, and spin split occurs for some configurations. A detailed analysis of the influences of impurity position and QD size on the impurity levels has been made, too.