| Summary: | 碩士 === 中原大學 === 電子工程研究所 === 86 === The main purpose of this study identified and resolved some significant problems of InP Liquid-phase Epitaxial Lateral Overgrowth (LPELO) technique. Further, it enables us to provide a deeper point of view to applications. First, we have grown by liquid phase epitaxial lateral overgrowth high quality InP using two different Crystal-oriented (100) and (111)B InP substrates. The choice for two substrates forms {111} and {100} facets easily. The patterned substrates especially lead to an extremely flat and high quality InP epilayer by LPELO technique. The Oxide layer (SiO2) Served as seed by exposing strips of the patterns constructs mechanism of LPELO. In other point of this study, the aim is to present a comprehensive and detailed variation of InP LPELO layers doped with rare-earth element Er. The nearly lattice match between the InP lateral epilayer and the InP substrate can be obtained. However, he lattice mismatch varies increasing gradually with the amount of Er element in the growth solution. All the Er-doped materials still exhibit the n-type conduction and the carrier concentrations of the Er-doped InP lateral layers are one or two orders of magnitude lower than those of undoped layers. This result implies that the high purity InP lateral layers can be easily obtained with doping Er element because of their donor-gettering effect. For LPELO layers grown with Er wt% in the range of 0-0.2 wt% in the growth solution, they have shining and mirror-like surface morphology. Mask patterns are the most important growth effect on high quality and large flat InP LPELO layer. Long parallel stripe pattern with line spacing 10-100um and line width 1um was formed by SiO2 film, i.e. an opening of protection mask by photolithographical exposure is used as a seed for lateral overgrowth. The line direction of the stripe pattern is aligned about 15 to 30 degree off <011> orientation. In our study, Crystallinity was characterized by X-ray diffraction (XRD), this datum showed that improved quality of InP lateral layer was observed upon the (100),(111)-oriented InP substrate. Both doping amount and baking process of Er affect the XRD intensity and full width at half-maximum (FWHM) of x-ray data that implies the two on growth conditions in the process. The contents of impurities of grown InP layers were moreover studied by energy dispersive x-ray spectroscopy (EDS). Optical property was measured by photoluminescence (PL), which showed strongly dependence on the amount of Er. From the measured PL spectra, a red shift of the Er:InP lateral epilayer with increasing amount of Er element can be observed.
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