Improved hot-carrier immunity in submicrometer MOSFETs with reoxidized nitrided oxides prepared by rapid thermal processing

摘要

The fabrication of 0.8- mu m MOSFETs using 7.7-nm-thick nitrided oxides reoxidized by rapid thermal processing at 900-1150 degrees C for 15-200 s is described. The hot-carrier-induced degradation was studied in terms of subthreshold swing, threshold voltage V/sub T/, and transconductance g/sub m/ voltage characteristics. Results indicate that rapid reoxidation markedly improves hot-carrier immunity; lifetimes reaching 30-mV V/sub T/ shift and 10 percent g/sub m/ degradation are improved by 3 and 1.5 orders of magnitude compared with those for thermal oxides, respectively. A degradation characteristic inherent to the (reoxidized) nitrided-oxide system is found, based on the gate-voltage dependence of g/sub m/ degradation.