Xiao-hang Li

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The fabrication studies of silica/polystyrene (PS) colloidal microlens arrays with various aspect ratios were performed on the III-nitride light-emitting diodes (LEDs). The use of colloidal-based microlens arrays led to significant enhancement in light extraction efficiency for III-nitride LEDs. In varying the aspect ratios of the microlens arrays, the(More)
The epitaxy optimization studies of high-quality n-type AlInN alloys with different indium contents grown on two types of substrates by metalorganic vapor phase epitaxy (MOVPE) were carried out. The effect of growth pressure and V/III molar ratio on growth rate, indium content, and surface morphology of these MOVPE-grown AlInN thin films were examined. The(More)
The enhancement of light extraction efficiency of InGaN quantum well light emitting diodes (LEDs) was achieved by employing the refractive index matched TiO microsphere arrays. The optimization studies of the dipping method and rapid convective deposition (RCD) method were carried out for the deposition of TiO microsphere arrays onto LEDs. The(More)
Metalorganic vapor phase epitaxy (MOVPE) nucleation studies of GaN on planar sapphire and nanopatterned AGOG (Deposition of Aluminum, Growth of Oxide, and Grain growth) sapphire substrates were conducted. The use of abbreviated GaN growth mode, which utilizes a process of using 15 nm low-temperature GaN buffer and bypassing etch-back and recovery processes(More)
The band structure of dilute-As GaNAs alloy with the As composition range from 0% to 12.5% is studied by using FirstPrinciple density-functional calculation. Our analysis shows that the dilute-As GaNAs alloy exhibits the direct band gap properties. The dilute-As GaNAs alloy shows a band gap range from 3.645 eV down to 2.232 eV with As content varying from(More)
Abbreviated growth mode of InGaN-based light-emitting diodes on nano-patterned sapphire leads to reduction in dislocation density and non-radiative recombination rate, and 37% increase in internal quantum efficiency.
The typical region of the Ebinur Lake Basin was chosen as study area. Landsat TM/OLI images for 1998, 2011 and 2013 were obtained. In the study area, landscape was classified into six types, including cropland, woodland, grassland, water body, bare lake bed, salinized land and unutilized land. Landscape indices and ecological risk index were calculated and(More)
The growths and characteristics of staggered InGaN quantum wells (QWs) and type-II InGaN-GaNAs QWs are presented for high-efficiency green-emitting light-emitting diodes (LEDs). Approaches for enhancing internal-quantum-efficiency, light-extraction-efficiency, and efficiency-droop in nitride LEDs are discussed.
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