It is demonstrated that thin oxynitride (SiON) films can be grown on single crystal (100) silicon substrates at a growth temperature of 400 °C, yielding high-quality electrical insulating and reliability properties which are compatible with the IC industry requirements. This is a drastic reduction in the growth temperature with respect to thermally grown SiO2 films at 1000 °C, which are conventionally used in semiconductor device fabrications. The realization of this growth method is made through the employment of high-density Kr/O2/N2 microwave-excited (2.45 GHz) plasma techniques. It is found that the electrical properties of the oxynitride films are strongly affected by the amount of the N2 added to the process gas mixture. For a properly selected mixture, the characteristics of the plasma-grown oxynitride films are shown to exhibit clear advantages with respect to those of SiO2 gate insulator films, grown by a conventional dry oxidation at 1000 °C, presently used in the IC industry. They demonstrate higher charge-to-breakdown (QBD) values, lower stress-induced leakage currents, and significantly lower gate voltage shifts (δVG). Accordingly, it is suggested that oxynitride films grown by the Kr/O2/N2 plasma technique are promising candidates for gate insulator films in scaled down MOS devices for the realization of future ultralarge-scale integration.
- Low temperature
- Oxynitride film
- Stress-induced leakage current (SILC)
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Condensed Matter Physics