Development of Plasma Based Ion Implantation System using an Electron Cyclotron Resonance Plasma Source with a Mirror Field and Synthesis of Carbon Thin Films

Abstract

A new type of plasma based ion implantation system was developed. An electron cyclotron resonance (ECR) plasma with a mirror field was used to generate a high density plasma with an electron density of 2×1011 cm-3. It was possible to apply negative high voltage pulses to the substrate up to -10 kV/20 A using a tube switch. Carbon films were prepared on Si wafer substrates with or without applying negative high voltage pulses. Diamond-like carbon (DLC) films were formed on each substrate placed on the hexagonal prism holder by the application of negative high voltage pulses to the substrate, though the polymer-like carbon films were formed without applying the pulse bias to the substrate. The mean surface roughness and the hydrogen content in the DLC films were decreased with decreasing the applied voltage. It is considered that the remaining hydrogen atoms were not bonded to the carbon atoms and that existed in the interstitial sites in the film from the results of the IR spectra which showed that the C–H bonds in the film had been terminated by applying the pulse bias. The DLC film prepared by the application of the pulse bias of low voltages such as -2 kV showed excellent tribological property.