Rapid Thermal Oxidation and Nitridation of Silicon

Book excerpt: Rapid thermal processing of silicon in oxygen and ammonia reactive ambients was employed to grow thin layers of Silicon dixoide, silicon nitride and nitroxide for high-quality gate insulators of submicron CMOS VLSI. Rapid thermal oxidation of (100) silicon in dry oxygen exhibited a nonlinear growth in the short-time regime. The oxide-growth rate rises as the oxidation time is reduced, and the highest rate occurs for the shortest rapid oxidation time. The formation kinetics of the surface and interface nitrogen-rich layers in rapidly nitrided oxide dielectrics were analyzed and correlated to their electrical performance. Rapid thermal nitridation of approx. 100 A SiO2 on silicon results in a negative shift of flatband voltage, a slight rise in surface-state density, a higher low-field and a lower high field conductivity, an improvement in the dielectric breakdown field, modified trapping characteristics, and a slower generation rate of new surfce states by the high-field electrical stress.