Optimized NH ₃ Annealing Process for High-Quality HfSiON Gate Oxide

Optimization of fabrication process in obtaining high-quality HfSiON gate-oxide metal-oxide semiconductor field-effect transistors (MOSFETs) by NH/sub 3/ post-deposition anneal (PDA) has been performed. At 600/spl deg/C anneal temperature, a longer anneal duration resulted in reduced leakage current density (J), reduced trapped charges, and lower hysteresis in capacitance-voltage curves, but with a slight increase in effective oxide thickness (EOT). Subsequent interfacial layer growth with longer anneal duration was attributed to the increase in EOT. MOSFET, fabricated by the optimized process of 600/spl deg/C, 40 s NH/sub 3/ PDA, showed superior I/sub d/--V/sub d/ (drain current-drain voltage) and charge-trapping characteristics as compared to control Hf-Silicate.