Modelling of intrinsic aluminum diffusion for future power devices

Aluminum as the fastest diffusing acceptor dopant is commonly used for the fabrication of silicon-based power semiconductors with p/n-junctions depths ranging from microns to more than hundred micron. Although used since long, its diffusion behavior is not sufficiently characterized to support computer-aided-design of new devices. Since modern processes are rather based on low temperatures, the inert diffusion of aluminum was investigated in the temperature range from 850 to 1100 °C. Combining nitridation and oxidation experiments, the fractional diffusivity via self-interstitials was determined.