XPS-Analysis of GaAs-Surface Quality Affecting Interelectrode Material Migration

XPS-studies of differently treated (100)-GaAs-surfaces were undertaken and correlated with the threshold for material migration across the GaAs-surface between neighbouring Al-electrodes. 5 surface conditions based on various etching and cleaning processes as commonly employed for the manufacture of GaAs devices have been investigated. The XPS-spectra show that high threshold values can be obtained by treatments resulting in a strongly reduced surface oxygen content.