DEUTERON BEAM ANALYSIS OF RAPID THERMAL NITRIDATION OF SILICON AND THIN SIO2-FILMS

In this paper, we report on the near surface atomic composition of freshly etched silicon, silicon with native oxide and silicon dioxide of a 36 angstrom thickness all thermally nitrided in a lamp-heated furnace. The substrates were nitrided by rapid thermal annealing (RTA) under NH3 at atmospheric pressure for 10, 20, 30, 40, 50, 60, 90 and 120 s at temperatures of 950, 1000 and 1200-degrees-C. The atomic quantities of nitrogen and oxygen in the films were determined by nuclear reaction analysis (NRA), using the nuclear reactions N-14(d, alpha)C-12 and O-16(d, p)O-17. A special study of the cross section of the nuclear reaction O-16(d, p)O-17 as a function of energy was undertaken to define the best measurement conditions. The atomic quantity of nitrogen in the film was found to be dependent on time, temperature and on the initial surface state. The incorporation speed of nitrogen appeared to be slower for the nitridation of silicon dioxide. For a 950-degrees-C nitridation temperature of silicon dioxide, the most important phenomenon seems to be an exchange between oxygen and nitrogen. At higher temperatures, the layer growth occurs along with the atomic exchange.