NITRIDED SiO//2 FILMS FOR VLSI APPLICATIONS.

Abstract

Thermal nitridation of SiO//2 films was carried out in the temperature range of 800-1000 degree C for times varying from 30 min to 4 h. The concentration and distribution of nitrogen in the film after nitridation depend on the nitridation temperature and time. For short nitridation time, nitrogen is incorporated at the top surface and at the Si-SiO//2 interface. With continued nitridation, nitrogen is incorporated in the bulk. After 4 h of nitridation, the film becomes uniform in nitrogen content. The relative dielectric constant of the film increases due to nitridation. The I-V characteristics of nitrided SiO//2 films are dominated by the Fowler-Nordheim tunneling mechanism. The fixed charge and interface trapped charge density of nitrided films are essentially the same as that of thermal SiO//2 films. Low field electrical breakdown events in nitrided SiO//2 films are less frequent. (Author abstract. )