Nanometric characterisation of III-nitride semiconductors

An investigation on the optical, composition and surtace properties of the ill-nitride ternary alloys is presented. The structures studied are single quantum wells (SQWs) and epilayers. The effects of various GaN cap thicknesses, well widths, Si doping concentrations in the barriers, InN compositions, epilayer thicknesses and substrates are examined. The techniques used are photoJuminescence (PL) and PL excitation (PLE) spectroscopy for investigating the optical properties, wavelength dispersive x-ray (WDX) and Rutherford backscattering spectrometry (RBS) for measuring InN composition. RBS is also used to study the crystalline quality of the samples; and secondary electron microscopy (SEM) and atomic force nlcroscopy (AFM) for examining the surface quality.EThOS - Electronic Theses Online ServiceGBUnited Kingdo