Gallium Phosphide High-Temperature Bipolar Junction Transistor

摘要

Preliminary results are reported on the development of a high-temperature (> 350 exp 0 C) gallium phosphide bipolar junction transistor (BJT) for goethermal and other energy applications. This four-layer p exp + n exp - pp exp + structure was fromed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The gallium phosphide BJT is observed to have a common-emitter current gain peaking in the range of 6 to 10 (for temperatures from 20 exp 0 C to 400 exp 0 C) and a room-temperature, punchthrough-limited, collector-emitter breakdown voltage of approximately -6V. Other parameters of interest include an f/sub/ = 400 KHz (at 20 exp 0 C) and a collector base leakage current = 200 mu A (at 350 exp 0 C). (ERA citation 06:012261)