Study of electron traps in n-GaAs grown by molecular beam epitaxy

Abstract
Electron trapping centers in n-GaAs grown by molecular beam epitaxy (MBE) have been studied by deep-level transient capacitance spectroscopy (DLTS). At least nine different electron traps are observed with energies ranging from 0.08 to 0.85 eV from the conduction band. Total electron trap concentrations in various samples range from the low 1014 cm−3 range to the mid 1012 cm−3 range. Studies of samples from various growth systems indicate that these traps are most likely due to chemical impurities. A comparison is made with electron traps in n-GaAs grown by vapor- and liquid-phase epitaxy as well as with the electron traps introduced into n-GaAs by 1-MeV electron irradiation.