Accumulation of electrons in GaAs layers grown at low temperatures and containing arsenic clusters

Abstract

Capacitance spectroscopy was used to investigate the properties of Au/GaAs Schottky barriers in structures in which a thin layer of gallium arsenide grown at low temperature (LT-GaAs) and containing As clusters was sandwiched between two uniformly copper-doped layers of n-GaAs grown at standard temperatures. We detected electron accumulation in the LT-GaAs layer surrounded by two depletion regions in the adjacent n-GaAs layers. Emission of electrons from the LT-GaAs layer at 300 K results in an extended plateau in the capacitance-voltage characteristic. It is found that the presence of the 0.1 µm thick LT-GaAs layer sandwiched between the two much thicker n-GaAs layers results in an increase in the breakdown electric field to values as high as 230 kV/cm, which is much higher than typical values for standard Au/n-GaAs structures.