Evaluation of diamond-like carbon films electrodeposited on an Al substrate from the liquid phase with pulse-modulated power

Diamond-like carbon (DLC) films with a resistivity of about 10(7) Omega cm and a thickness of about 1 mum were deposited on an Al (99.9%) substrate fr om N,N-dimethylformamide (DMF) and acetonitrile by liquid deposition using a pulse-modulated power. The structure of the films was characterized by X- ray photoelectron spectroscopy (XPS) and Raman spectroscopy. XPS showed tha t the main composition of the films was carbon and Raman spectra showed tha t the films were typical DLC films. The results suggest that a high potenti al is preferential to the formation of sp(3) structure carbon and the methy l group of the solvents has a critical function in the formation of the fil ms. By contrasting the results on Al and on conductive glass from the same solvents we discover that the character of the films, such as appearance, r esistivity, thickness and the formation process are mainly determined by th e nature of the substrate. (C) 2001 Elsevier Science Ltd. All rights reserv ed.