FTIR dosimetry mapping of as-implanted SIMOX wafers

This report summarizes recent advances in the application of the On-Line's FTIR FilmExpert/sup TM/ metrology tool for the characterization and uniformity control of SIMOX wafers. The SOI buried layer needs to be uniform within +/5%. This translates to +/- 25 A for 500 A SOI films and respectively less for 200 A SOI films over the large diameter wafers. The criterion is related to the requirement for the uniformity of threshold voltage and corresponding doping levels. The advanced FTIR measurements demonstrated the capability to perform fast mapping of oxygen implant dose with high precision (better than 0.5%) and excellent spatial resolution on as-implanted wafers. i.e. before time-consuming annealing which,finalizes SIMOX fabrication. The results illustrate the potential of the FilmExpert/sup TM/ as a process control tool for optimizing low-dose and ultra low-dose SIMOX manufacturing.