2-DIMENSIONAL ALUMINUM DIFFUSION IN SILICON - EXPERIMENTAL RESULTS AND SIMULATIONS

Two-dimensional diffusion of aluminum implanted through a mask in sili con has been measured after furnace or rapid thermal annealings. Chemi cal staining on cross-sectioned samples was used to determine both the vertical and the lateral junction depths. The spreading resistance st andard procedure was adopted to measure the vertical profiles while a new procedure was developed for the determination of the lateral diffu sion profiles. The difference in the measured profile by staining and spreading resistance is related to the spilling phenomenon that distor ts the carrier concentration profile on beveled samples. Moreover, exp erimentally aluminum diffusion parameters and segregation coefficient at the Si/SiO2 interface have been introduced in advanced one-dimensio nal (SUPREM III) and two-dimensional (SUPREM IV) process simulators. T he good agreement between the simulated and the experimental data, for both the lateral and the vertical directions, indicates that these pr ocess simulators can reproduce with accuracy the aluminum diffusion.