| III-Nitride Semiconductor Materials are highly promising for the fabrications of optical devices especially in UV region. And Quantum Dots structure is theoretically predicted to have higher quantum efficiency, contrast and signal-to-noise ratio. The research study done in this thesis is part of a Ph.D project. This thesis studies the growth of GaN QDs on Sapphire for the purpose of validating the new MOCVD system. It also studies the growth of AlN film on Sapphire for the preparation to grow GaN QDs on. For the first time, the size and density of GaN QDs grown on Sapphire is studied by changing the growth condition. Techniques were developed for the growth of smooth surface AlN film directly on Sapphire instead of 6H-SiC which is commonly used and expensive. Interlayer structures were grown and characterized. The RMS of local area is reduced as low as 0.436nm. AFM and X-Ray were used to study issues related to surface condition, stain and interlayer effects. The growth of GaN QDs on AlN film is a mid-step. In fulfilling the whole project, GaN QDs are going to be grown on AlGaN for the purpose of fabricating optoelectronic devices. |
