Electrical Activity of Defects in Molecular Beam Epitaxially Grown GaAs on Si and Its Reduction by Rapid Thermal Annealing

The advantages of GaAs on Si technology have now been well recognized, and fabrication of a variety of new device structures in this material has been demonstrated. The efforts thus far have been largely to demonstrate working devices and detailed characterization has been lacking. Although many of the electronic properties of GaAs on Si are quite similar to those on GaAs, reverse leakage currents in p/n and Schottky diodes are somewhat larger. Further, current gains in GaAs/AlGaAs HBTs on Si are found to be much lower than on GaAs. The effects of large dislocation densities and strain on device properties are not clear at this stage.