Effects of substrate-potential on the growth of diamond films through hot-filament chemical vapour deposition

Variation in substrate bias greatly influences diamond film properties, which may be important in low power optoelectronics devices. In this work, effect of the floating potential (FP) on film uniformity, surface morphology and crystallite orientation was studied. Diamond films deposited on two pieces of silicon substrates, by using the hot-filament chemical vapour deposition technique, with one substrate set at ground potential (GP) while the other at a floating potential (FP). The standard techniques like scanning electron microscope and Raman spectra were used for film characterisation. It was observed that FP leads to increase in the density of {100} oriented grains but at the cost of growth rate and film uniformity.