Properties of C-doped LT-GaAs grown by MBE using CBr4
MBE grown LT-GaAs contains a high concentration of excess As which gives rise to ultra-fast carrier-trapping time and excellent radiation hardness. Thermal annealing can result in a dramatic decrease in AsGaconcentration, accompanied by out-diffusion of excess As into adjacent layers. Doping the LT-GaAs layers with Be can thermally-stabilize AsGa antisite defects but Be is known to be mobile at high temperatures. Carbon has been demonstrated as an attractive p-type dopant in GaAs. In this work, we report on a comparative study of the resistivity and carrier lifetimes of as-grown and annealed LT-GaAs : C and LT-GaAs : Be.
Source: Journal of Crystal Growth