| Summary: | 博士 === 國防大學中正理工學院 === 國防科學研究所 === 91 === We discuss the effects of lateral wet oxidation and ion implantation on AlGaAs DBRs. The AlxGa1-xAs oxide is stable, amorphous, solid-phase (AlxGa1-x)2O3. For AlxGa1-xAs layers embedded in multi-layer structure, a stable oxidation process is achieved by precisely control the flow rate of carrier gas, oxidation temperature and oxidation period, the thickness of AlxGa1-xAs layers, etc. The oxidation rate of the DBR implanted with oxygen ions will be enhanced at the temperature range of 350~450℃. We thought the enhanced oxidation rate is dominantly resulted from the change of surface energy or strain between oxide layers and epi-layers. In addition, for the DBRs implanted with hydrogen, oxygen, silicon, or phosphorous ions, respectively, the central wavelength of reflectivity spectra will shift toward longer wavelength and the background reflectance is increased. According to our calculation and discussions, those are related to inter-diffusion of aluminum atoms in DBR. Finally, for the surface-emitting LED or RCLED with DBR structure, its optoelectronic properties are improved by additional process of lateral wet oxidation or ion implantation.
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