C-V profiling of ultrashallow junctions using a step-like background doping profile

A novel C-V profiling method that enables profiling of ultrashallow and ultra-abrupt junctions is described. The method takes advantage of a peculiar shape of the C-V characteristic that is obtained with a step-like or other abruptly changing background profile. The method is analytically described and confirmed by MEDICI simulations. A step-like background As profile and an ultrashallow and ultra-abrupt p⁺ junction were grown by respectively Si and pure boron RPCVD. Using these techniques, junctions with a doping depth of around 7 nm and with a slope of around 2.5 nm/dec were fabricated and measured.