Permittivity of GaAs epilayers containing arsenic precipitates

The real part of the permittivity of annealed low temperature grown gallium arsenide (LTG GaAs) has been measured via capacitance measurements taken o n p-i-n devices. The intrinsic region of the devices contained LTG GaAs ann ealed at 700, 800, and 900 degrees C for 30 s. The capacitance trends as a function of frequency for the annealed LTG GaAs samples were compared to th at of GaAs grown at a standard substrate temperature. An increased screenin g of the electric field was observed for the LTG samples as the test freque ncy was lowered. The capacitance measurements were taken at various test te mperatures, enabling the computation of an activation energy of the electri c field screening in the annealed LTG GaAs from Arrhenius plots. (C) 1998 A merican Institute of Physics. [S0003-6951(98)04631-2].