Heat treatment of semi-insulating chromium-doped gallium arsenide substrates with converted surface removed prior to molecular beam expitaxial growth

Abstract

Silicon-doped gallium arsenide molecular beam epitaxy (MBE) layers were grown on chromium-doped semi-insulating GaAs (Bridgeman grown) heat-treated (converted surface removed before growth) or nonheat-treated substrates. Secondary ion mass spectrometric (SIMS) measurements show a marked reduction of outdiffused manganese in layers grown on heat-treated substrates with converted surface removed prior to MBE growth. Secondary ion mass spectrometric studies and capacitance voltage free-carrier profiling indicate a redistribution of Si in layers grown on nonheated substrates not observed in epilayers on heat-treated substrates (converted surface removed prior to MBE growth).