ELECTRICAL-PROPERTIES OF SILICON-NITRIDE FILMS GROWN ON A SIGE LAYER BY DISTRIBUTED ELECTRON-CYCLOTRON-RESONANCE PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION

Silicon nitride films have been deposited on relaxed Si0.83Ge0.17 film s using distributed electron resonance plasma-enhanced chemical vapor deposition without intentional substrate heating. The electrical prope rties of metal-insulator-semiconducror structures have been investigat ed. The electrical properties are strong functions of the post-process ing treatment. The hysteresis of C-V curves can be reduced significant ly after 30 min post-metallization annealing at 450 degrees C in formi ng gas. The flat-band voltage is then very low, thereby indicating tha t positive charges retained in the silicon nitride films are compensat ed forby negative charges located at the interface with the SiGe alloy . Conduction properties have also been analyzed from I-V measurements. A critical field of approximate to 2 MV cm(-1) and a high resistivity of approximate to 2 x 10(15) Omega cm have been obtained. For higher electric fields, the leakage current is governed by a Poole-Frenkel co nduction mechanism.