FORMATION OF SILICON-NITRIDE LAYERS BY NITROGEN ION IRRADIATION OF SILICON BIASED TO A HIGH-VOLTAGE IN AN ELECTRON-CYCLOTRON-RESONANCE MICROWAVE PLASMA

Silicon was pulse biased to -50 kV in a nitrogen plasma generated by m icrowave excitation in electron cyclotron resonance mode. Nitrogen ion s from the plasma were accelerated in the electrical field and implant ed into the silicon. Cross-section transmission electron microscopy sh owed that the resulting surface layer was amorphous. Tempering at 1500 K led to the formation of a 25 nm thick continuous crystalline film o f alpha-Si3N4 buried under a 50 nm thick amorphous surface zone. (C) 1 998 American Institute of Physics. [S0003-6951(98)03610-9].