| In this dissertation, the structural, optical and photoluminescence characteristics of AgxO, GaN and CNX thin films was deeply studied by spectroscopic ellipsometric (SE) technique, combined with other measurement methods, and the experimental results were analyzed and explained by numerical calculation based on the macroscopic model. The enhancement of the magneto-optical Kerr effect in Ag (3nm) /TbFeCo (50nm) bilayer films at short wavelength was also measured and studied by a self-made magneto-optical Kerr system. The main conclusions were listed as follows:1. By using LAB600-SP magnetron-controlled sputtering system, made by Germany Ley-bold Company, a series of AgxO thin film samples were prepared at different O2 gas ratio Po (O2/ (O2+Ar)) by reactive sputtering Then all the samples were annealed at different temperatures and naturally cooled to room temperature in high-vaccum conditions. All the annealed and non-annealed AgxO samples were studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry (SE). Through the study of the optical constants of AgxO sample( X = 632.8 nm) prepared at different O2 gas ratio (Po=0.2,0.3,0.4,0.5,0.57,0.67), it was found out that refractive index and extinctive coefficient gradually changed with Po increasing and changed unconspicuous at the O2 gas ratio between 0.5 and 0.6. The refractive index and extinctive coefficient obtained in this region was slightly different from that reported by Schmidt et al [8] with the complex refractive index of Ag2O (n=2.5 and K=0.11) at a wavelength of 632.8 nm, which might be due to the existence of a small amount of Ag or AgO particles in as-dep AgxO samples mainly made up of Ag2O, as confirmed by XRD and XPS . The AgxO prepared at the O2gas ratio between 0.5 and 0.6 would be suitable for optical and magneto-optical storage application since the optical constants changed unconspicuous in this region and the corresponding magneto-optical disk including AgxO layer could obtain larger signal noise ratio(SNR), which was proved in new magneto-optical disk experiment by Kim etal.According to the structural change of AgxO after annealed, all the as-dep AgxOsamples could be taken into two groups. The amorphous structure of AgxO, prepared at Po smaller than 0.4, would change into the multi-crystalline structure of (Ag +Ag2O) after annealed at high temperature. In the multi-crystalline structure of (Ag +Ag2O), Ag was dominated. While the amorphous structure of AgxO, prepared at Po larger than 0.4, would turn into the multi-crystalline structure of Ag2O after annealed at high temperature. As confirmed by XRD and XPS of two typical groups of AgxO (Po=0.3 and 0.57 respectively), all the as-dep AgxO samples showed amorphous structure where AgO and Ag2O coexisted. During annealing, the as-deposited amorphous structure of AgxO would be crystallized and temperature-dependent decomposition would occur. The threshold of the thermal decomposition temperature for AgO and Ag2O was about 200 C and 300 C respectively, which was in good agreement with the results reported in other work. However, what's different from the results reported in other work was that these two groups of AgxO samples didn't show the multi-crystalline structure of pure silver, and but showed the multi-crystalline structure of (Ag+Ag2O) and Ag2O respectively. The different experimental results could be explained by different density caused by different preparation conditions.2. High-quality GaN thin film sample with a thickness of about 1.5+0.5um was prepared on (0001) sapphire substrate by low pressure metal-organic chemical vapor deposition (LPMOCVD) multi-step growth procedure. Seen by XRD, the as-dep GaN film showed two strong (0001) -oriented Wurtzite GaN characteristic peaks due to the (0002) and (0004) diffractions peaks of the Wurtzite GaN. The existence of the strong (0002) diffraction peak with a very narrow FWHM value of about 0.1 and the high order GaN (0004) diffraction peak confirmed a crystallined quality of the GaN film...
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