DIAMOND-LIKE CARBON-FILMS GROWN USING A SADDLE FIELD SOURCE

This article reports the measurement of deposition rate, dark conductivity versus temperature, optical band gap, refractive index, extinction coefficient, hardness, adhesion, and internal stress of diamond-like carbon (DLC) films grown by aspirating hydrocarbon gases (CH4 and C2H2) and C6H6 vapors into a saddle field source. The source operates at 0.7-1.0 kV in the pressure range of 1.0X10(-4)-7.OX10(-4) Torr and is of a modular design to cover increasingly larger areas. DLC films have been grown for the first time using CH4 by this technique. The effect of source to substrate distance on the deposition rate and uniformity of the films has been studied at varying bower to the source using C2H2 gas. The films are found to be hard and they adhere well to 7059 glass, quartz, silicon, Mo, and Mylar substrates. Though the deposition rate increases with increasing power and with increasing carbon to hydrogen ratio of the hydrocarbon feedstock, the material properties are relatively independent of the type of hydrocarbon used. (C) 1995 American Vacuum Society.