Determination of Thickness for the Individual Layer of Strained P-Type Al0.11Ga0.89NGaN Superlattice by High Angle Annular Dark Field Scanning Transmission Electron Microscopy
AlGaN/GaN superlattice are the important structure of optoelectronic devices such as light-emitting diodes and laser diodes. The nanostructure of the superlattice can greatly influences the optical electrical properties of final LD and LED . It is impossible to evaluate their thickness by TEM when it’s aluminum component lower than 14%.We investigated the nanostructure of strained p-type Al0.11Ga0.89N/GaN superlattice grown on sapphire by high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM).By an average filtering technique, the thickness of the AlGaN layers and GaN layers were determined to be 2.409±0.092 nm and 2.371±0.062 nm from the HAADF-STEM images, respectively.
Zhengyi Jiang, Jingtao Han and Xianghua Liu
H. Liao et al., "Determination of Thickness for the Individual Layer of Strained P-Type Al0.11Ga0.89NGaN Superlattice by High Angle Annular Dark Field Scanning Transmission Electron Microscopy", Advanced Materials Research, Vols. 152-153, pp. 879-882, 2011