Low-Energy Ion Technique for Semiconductor Surface Preparation

Abstract

We proposed an experimental technique for determining the sputtering yields of two-component semiconductors – gallium arsenide and indium arsenide by low-energy argon ions. It was suggested to measure the volume of a crater formed by inert ions bombarding on the target surface using the method of scanning laser confocal microscopy. It was demonstrated that in the energy range from 100 to 300 eV, the energy dependence of sputtering yields for these materials is practically linear. It is established that the sputtering yields for normal bombardment by argon ions at optimum energy of 150 eV are equal to Y(GaAs) = 0.41 and Y(InAs) = 0.73. It is found that an increase in the etching time of the surface of gallium arsenide and indium arsenide leads to a characteristic transformation of the surface relief. The studies of the sputtering of two-component targets indicate the initial strong non-stechiometry. Etching for a certain period of time leads to an equalization of the concentrations of the sputtered components. It was found that to obtain a uniform composition of the mass flow it is necessary to pre-sputter the targets with shielded substrates.