The valence-band offset (DeltaE(V)) has been determined to be similar to2.6
eV at the Ga2O3(Gd2O3) GaAs interface, and similar to1.1 eV at the Ga2O3(G
d2O3)-GaN interface by high-resolution X-ray photoelectron spectroscopy wit
h synchrotron radiation beam. The Pt-Ga2O3(Gd2O3)-GaAs MOS diode exhibits a
current-voltage characteristics dominated by Fowler-Nordheim tunneling. Fr
om the current-voltage data at forward and reverse biases, we have extracte
d a conduction-band offset (DeltaE(C)) of similar to1.4 eV at the Ga2O3(Gd2
O3)-GaAs interface and an electron effective mass m* similar to 0.29m(e) of
the Ga2O3(Gd2O3) layer. Consequently, the energy-band gap of Ga2O3(Gd2O3)
is similar to5.4 eV, while DeltaE(C) for the Ga2O3(Gd2O3)-GaN interface is
similar to0.9 eV. (C) 2001 Elsevier Science Ltd. All rights reserved.