| Summary: | 碩士 === 國立交通大學 === 電子研究所 === 98 === In this thesis, we aimed at investigating the selective area quantum well intermixing induced by dielectric capping layers. The InGaAs/GaAs quantum well heterostructures were capped with SiO2 and TiO2 films, and high-temperature rapid thermal annealing was applied subsequently. The optical properties were examined by measuring photoluminescence and micro-photoluminescence spectra at 77 K. When the rapid thermal annealing was processed at 900 ℃, an energy blue-shift as large as 100 meV was observed from the SiO2-enhanced quantum well intermixing, and a meaningful energy red-shift of 9.25 meV was offered with the help of TiO2 as an inhibitor of the thermal-induced atomic interdiffusion. Furthermore, the patterns with circular apertures which are sub-micrometer in diameter were fabricated on the SiO2 capping layers as masks. From the aperture-dependent micro-PL spectra, we suggest that the minimum effective diameter of apertures is limited to a specific value for each RTA temperature. We also demonstrated the distribution of electrons from the points of view both in the real space and in the energy space so as to explain the excitation power-dependent transformation of emission peaks. The controllable selective area InGaAs/GaAs quantum well intermixing was successfully accomplished on the sub-micrometer scale with the assistance of patterned SiO2 capping layer, and this would pave a way to realize the monolithic integration of optoelectronic devices.
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