GAASSB FOR HETEROJUNCTION BIPOLAR-TRANSISTORS

The advantages of using GaAsSb in Heterojunction Bipolar Transistors ( HBT's) are discussed with emphasis on two recent experimental results in the AlGaAs/GaAsSb material system. The performance of a prototype n -p-n AlGaAs/GaAsSb/GaAs double HBT (DHBT) that exhibits stable current gain with maximum collector current density of 5 x 10(4) A/cm2, and a p-n-p AlGaAs/GaAs HBT with a superlattice GaAsSb emitter ohmic contac t which has a specific contact resistivity of 5 +/- 1 X 10(-7) OMEGA . cm2 across the sample, are examined.