Electrical isolation of n-type GaAs layers by proton bombardment: Effects of the irradiation temperature

The electrical isolation in n-type GaAs layers produced by proton irradiation at temperatures from -100 to 300 °C was investigated. The threshold dose for the isolation (D_th) was found almost identical for irradiation at temperatures from -100 to 220 °C. At 300 °C, a dose of ≅1.3 times higher is required for the isolation threshold. In samples irradiated to a dose of D_th at -100 °C or nominal room temperature, the isolation is maintained up to a temperature of ≈250 °C. In those samples irradiated at 300 °C it persists up to ≈350 °C. For doses of 3D_th or above, the stability of the isolation is limited to temperatures of 450–650 °C, irrespective of the irradiation temperature (T_i). For practical applications where doses in excess to 5D_th are usually employed, the irradiation temperature (from -100 to 300 °C) has only a minor effect on the formation and thermal stability of the electrical isolation. © 1998 American Institute of Physics.