This letter investigates the chemistry and energy band structure of (Gd2 O3) 1-x (SiO2) x (0≤x≤1) films grown on n -GaAs (001). Dielectric band gap and interfacial band alignment of Gd2 O3 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.
Bibliographical noteFunding Information:
This work was supported by Korea Research Foundation Grant No. KRF-2004-041-D00431. Experiments at PLS were supported in part by MOST and POSTECH.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)