Electrical properties and thermal stability of Be-doped nonstoichiometric GaAs

Abstract

Beryllium doping of arsenic rich GaAs grown by MBE at low temperatures (LT-GaAs) allows one to grow GaAs with ultrashort carrier lifetimes at growth temperatures of 250/spl deg/ to 300/spl deg/C. Hall effect and resistivity measurements showed that in as-grown samples hopping conduction can be suppressed in this growth temperature range. Semi-insulating behavior of as-grown LT-GaAs:Be can be achieved by careful adjustment of temperature and Be-doping. In addition, Be-doped LT-GaAs grown in this temperature range shows increased thermal stability of the arsenic antisite defects (As/sub Ga/).