A thin film preparation using focused high power ion beam

Abstract

The advantages of the method of precipitation of evaporated target material with short pulse and high power ion beam are: high precipitation velocity (1 /spl mu/m per shot); possibility of film formation at high area substrate( 100 cm/sup 2/); moderate vacuum conditions needed (10/sup -4/-10/sup -5/ Torr)-two orders higher compared to other methods; and high melting temperature target usage. These advantages are provided by action of pulsed ion beam at the target, when the effective energy transfer into target occurs, but irradiation energy losses are minimal. The thickness of the evaporated layer of the target is determined by ion range in material (usually 1-10 /spl mu/m) providing high velocity precipitation. Pulsed action of target plasma results in thermal and mechanical dynamic loading, that is important for film properties. The usage of the described method for formation of diamond like film is of the most interest. In order to precipitate the carbon films we used high power ion beam with the following parameters: E=600 keV, I=60 kA, t=80 ns. The ion beam was generated in a focusing B-applied diode at GIMN accelerator. The ion beam consisted of approximately 70% of protons and 30% of carbon ions. The ion current density in the focal plane reached 9 kA/cm/sup 2/ that corresponds to 300 J/cm/sup 2/. Thickness of the precipitated films made up to 100 nm per shot at the distance between target and substrate of 4 cm. In the case of glass substrate, its surface layer was strongly destroyed. The electrical resistance of film was at the level of 100 Ohm.