Controlling A-center concentration in silicon through isovalent doping: Mass action analysis

It has been determined experimentally that doping silicon with large isovalent dopants such as tin can limit the concentration of vacancy-oxygen defects, this in turn, can be deleterious for the materials properties and its application. These results have been supported by recent calculations based on density functional theory employing hybrid functional. In the present study, we employ mass action analysis to calculate the impact of germanium, tin and lead doping on the relative concentrations of vacancy-oxygen defects and defect clusters in silicon under equilibrium conditions. In particular, we calculate how much isovalent doping is required to constrain vacancy-oxygen concentration in silicon and conclude that Sn and Pb doping are the most effective isovalent dopants. The results are discussed in view of recent experimental and computational results

Vacancy-oxygen defects in silicon: the impact of isovalent doping

Silicon is the mainstream material for many nanoelectronic and photovoltaic applications. The understanding of oxygen related defects at a fundamental level is essential to further improve devices, as vacancy-oxygen defects can have a negative impact on the properties of silicon. In the present review we mainly focus on the influence of isovalent doping on the properties of A-centers in silicon. Wherever possible, we make comparisons with related materials such as silicon germanium alloys and germanium. Recent advanced density functional theory studies that provide further insights on the charge state of the A-centers and the impact of isovalent doping are also discussed in detail