Comparative study of ZnO and GaN films grown by MOCVD

ZnO and GaN films were grown by MOCVD. AFM, DCXRD and photoluminescence were used to study the surface morphologies, structural and optical properties of the films. By a comparison of the measurement results, it was shown that the structural and optical properties of the ZnO films are superior to the GaN films. The (102) FWHM and the free/bound exciton intensity ratio of the ZnO films are the best results ever reported for ZnO films. To evaluate the overall quality of the GaN films, an InGaN/GaN MQW LED was fabricated and the LED showed good I-V characteristics and its light output power was 6 mW at 20 mA, which indicated the good quality of the GaN layers and then indirectly suggested the high quality of the ZnO films.