Controlled band offset in (Gd2O3)1-x(SiO2)x(0≤x≤1)/n-GaAs(001) structure -: art. no. 022104

This letter investigates the chemistry and energy band structure of (Gd2O3)(1-x)(SiO2)(x)(0 <= x <= 1) films grown on n-GaAs (001). Dielectric band gap and interfacial band alignment of Gd2O3 films were modified by compounding with SiO2. Binding energy shift of core level was observed from different electronegativity of second nearest-neighbor element. Controlled parameters of energy band structure were systematically characterized by valence band, absorption, and energy loss spectra. Assuming no Fermi level pinning in the midgap of n-GaAs, band offset values represent almost linear dependency on the concentration of SiO2. The correlation of band offset with the electrical properties, as probed by capacitance and leakage current measurements, was also discussed. (c) 2005 American Institute of Physics.