Determination of aluminum diffusion parameters in silicon

Aluminum as the fastest diffusing acceptor dopant in silicon is commonly used for the fabrication of power semiconductors with p-n junction depths ranging from some microns to more than hundred microns. Although used since long, its diffusion behavior was not sufficiently characterized to support computer-aided design of new devices. In this work, the intrinsic diffusion of aluminum was investigated in the temperature range from 850 to 1290°C. Combining nitridation and oxidation experiments, the fractional diffusivity via self-interstitials was determined. By diffusion in high-concentration boron- and phosphorus-doped silicon the behavior of aluminum under extrisic conditions was investigated.