Some properties of amorphous carbon films deposited on the grounded electrode of a RF-PECVD reactor from Ar–CH4 mixtures

We have studied the transport and optical properties of hydrogenated amorphous carbon materials deposited on the grounded electrode of a rf powered Plasma Enhanced Chemical Vapour Deposition unit. A surprising increase in deposition rate of the materials is reported in the presence of a small amount of solid phase Si in the deposition chamber. Samples have been characterized by optical absorption and Raman spectroscopy. The samples have very low conductivity in dark and under visible light. With UV light (λ ⩽ 250 nm), the photoconductivity of the samples is nearly 10−8 S cm−1 with a photons flux of N ≈ 5 × 1012 photons cm−2 s−1, indicating that these materials are promising candidates for UV sensor.