ABSTRACTThe surface chemical states of MOCVD grown GaN, AlGaN and InGaN, and the influence of different dopants have been studied with x-ray photoelectron spectroscopy (XPS). The results show that for most of the samples the N 1s peak can be fitted with a dominant GaN peak at the binding energy of 397.2 ± 0.2 eV and a small N-H peak at the binding energy of 398.5 ± 0.2 eV, while Ga 3d can be deconvoluted into three peaks, i.e., elemental Ga at 18.5 ± 0.1 eV, GaN at 19.7 ± 0.1 eV, and Ga2O3 at 20.4 ± 0.1 eV. Si-doping appears to have small influence on the surface chemical states of GaN. Compared with Si-doping, the influence of Mg-doping appears -to be larger. In addition to a change in the component intensities, Mg-doping also causes the N ls and Ga 3d peaks to broaden. The ternary AlxGa1−xN (x ∼ 0.025) sample shows aluminum surface segregation, while the undoped InxGa1−xN(x ∼0.12) shows indium surface deficiency
Surface Chemical States of Sizing Agents on AKD/Cellulose Blends by X-Ray Photoelectron Spectroscopy