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Highly c -axis oriented GaN films were deposited on Cu coated glass substrates using electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition (ECR-PEMOCVD). In-situ reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD) and atomic force microscopy (AFM) were used to systematically analyze the influence of TMGa flux on the crystalline quality of the GaN films. GaN films with strong c -axis preferred orientation were achieved under the optimal TMGa flux of 1.4 sccm. Moreover, a strong near band edge (NBE) emission peak located at 354 nm was observed in the room temperature PL spectrum for the optimized GaN sample. The GaN/Cu/glass structure shows great potential for application in large area low cost GaN-based LED devices.

Annealing studies were performed to investigate the effects of heat treatment on InN thin films by changing the annealing condition from vacuum to high pressure N 2 . A significant variation of ∼400 meV in the surface work function was observed for InN films. The basic principles of Kelvin probe measurement revealed that the surface band bending E SBB is crucial in investigating the significant changes of surface work function on the InN. The stoichiometric ratio imbalance of In and N was indirectly determined to be the main cause of the variation in band bending by analyzing the X-ray diffraction and energy dispersive X-ray measurements. Thus, the annealing treatment could be an effective method to adjust the surface work function of InN by changing the annealing condition from vacuum to high pressure N 2 .

The symplectic geometry approach is introduced for accurate bending analysis of rectangular thin plates with two adjacent edges free and the others clamped or simply supported. The basic equations for rectangular plates are first transferred into Hamilton canonical equations. Using the symplectic approach, the analytic solution of rectangular thin plate with two adjacent edges simply supported and the others slidingly supported is derived. Accurate bending solutions of title problems are then obtained using the superposition method. The approach used in this paper eliminates the need to pre-determine the deformation function and is hence more reasonable than conventional methods. Numerical results are presented to demonstrate the validity and efficiency of the approach as compared with those reported in other literatures.

Exact bending solutions of fully clamped orthotropic rectangular thin plates subjected to arbitrary loads are derived using the finite integral transform method. In the proposed mathematical method one does not need to predetermine the deformation function because only the basic governing equations of the classical plate theory for orthotropic plates are used in the procedure. Therefore, unlike conventional semi-inverse methods, it serves as a completely rational and accurate model in plate bending analysis. The applicability of the method is extensive, and it can handle plates with different loadings in a uniform procedure, which is simpler than previous methods. Numerical results are presented to demonstrate the validity and accuracy of the approach as compared with those previously reported in the bibliography.