STUDY ON FORMATION OF CARBON NANOTIPS BY NEGATIVE BIAS-ENHANCED HOT FILAMENT CHEMICAL VAPOR DEPOSITION WITHOUT CATALYST

Carbon nanotips were grown on a silicon substrate by negative bias-enhanced hot filament chemical vapor deposition without catalyst, using a mixture of methane, ammonia and hydrogen as the reaction gases. It was evidenced that the plasma caused by the bias played a key role in the formation of the carbon nanotips. Due to occurrence of plasma during growing carbon nanotips, the gases were ionized into various ions. Based on different effects of the ions, a growth mechanism of the carbon nanotips was put forward.