Determination of aluminum diffusion parameters in silicon

Abstract

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 a hundred microns. Although long used, its diffusion behavior was not sufficiently characterized to support computer–aided design of 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 extrinsic conditions was investigated.