LAYER AND INTERFACE ANALYSIS OF ULTRA-THIN ION-BEAM PRODUCED SILICON-NITRIDE LAYERS BY NRA AND TEM

Ultra thin silicon nitride layers with stoichiometric N/Si ratios in t he maximum of the depth distributions were produced by implanting 10 k eV N-15(2)+ ions into single-crystal silicon at RT under high vacuum c onditions. The N-15 depth distributions were measured by the resonant nuclear reaction N-15(p,alpha gamma)C-12 (NRA). The depth resolution a t the surfaces of the specimens is 3 nm, if the tilt angle is 55 degre es. The layer structure of the implanted region and the relevant real geometry was characterized by high resolution TEM. High-temperature st ability of the N-15 depth distribution in the implanted specimens was proved by electron beam rapid thermal annealing (EB-RTA) at 1100 degre es C. The results obtained by NRA and TEM are in agreement.