EFFECTS OF HYDROGEN AND RF POWER ON THE STRUCTURAL AND ELECTRICAL-PROPERTIES OF RF-SPUTTERED HYDROGENATED AMORPHOUS-SILICON CARBIDE FILMS

The effects of the rf power (100 to 600 W) and the hydrogen partial pr essure (P-H=0.15 to 0.6 Pa.) on the deposition rate and the structural and electrical properties of rf sputtered hydrogenated amorphous sili con carbide (a-Si1-xCx:H) films were investigated. The films were depo sited in an argon plus hydrogen ambient. The deposition rate increased with increasing rf power, but decreased with increasing P-H. The refr active index increases from 1.85-3.6 as the rf power increases from 10 0-600 W and from 2.8 to 3.5 as P-H increases from 0.15-0.6 Pa. The opt ical gap increases from 1.5 to 2.15 eV as P-H increases from 0.15-0.6 Pa, but decreases from 2.8-1.38 eV as the rf power increases from 100- 600 W. The Si-C bond gave the most prominent absorption peak in the in frared spectra, and increased with increasing rf power but not affecte d by changes in P-H. The Si-H bonds increases from 3.06X10(21) to 1.64 X10(22) cm(-3) as P-H was increased from 0.15-0.6 Pa. The optical gap increases from 1.5-2.15 eV and the conductivity reduces from 7.3X10(-9 ) to 1.9X10(-11) Ohm(-1) cm(-1) accordingly. No C-H-n stretching mode was detected in all the films and this was attributed to the low carbo n content of the films, We conclude that rf sputtering technique is no t effective in varying the carbon content in a-Si1-xCx:H films. (C) 19 96 American Institute of Physics.