Browsing by Author "Huang, Ping-Wei"

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Effect of Ni thin film on the reflectivity of ITO/Ag mirrors of GaN light-emitting diodes
(2008)
Wu, Yew Chung Sermon
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Huang, Ping-Wei
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材料科學與工程學系
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Department of Materials Science and Engineering
The effect of Ni thin film on the reflectivity of the indium tin oxide (ITO)/Ag mirror of GaN light-emitting diodes after annealing at 200 degrees C was investigated. Samples designated as "ITO/Ag" were ITO/Ag films without a Ni layer. "ITO/Ni/Ag" and "ITO/Ag/Ni" were ITO/Ag films with a Ni layer either between the ITO and Ag films, or on the back side of Ag film. "ITO/Ni/Ag/Ni" were ITO/Ag films with Ni layers on both sides of Ag film. It was found that annealed ITO/Ni/Ag/Ni had the highest reflectivity (96.3%) because two Ni layers can retard the agglomeration of Ag and the in-diffusion of Ag into ITO.
Improved Performance of AlGaInP LEDs by a Periodic GaP-Dish Mirror Array
(2009-10-01)
Huang, Ping-Wei
;
Wu, Yew Chung Sermon
;
材料科學與工程學系
;
Department of Materials Science and Engineering
A periodic GaP-dish mirror structure was introduced into AlGaInP light-emitting diodes (LEDs) through wet etching and Si wafer bonding process. It was found that the performance of these GaP-dish LEDs was better than that of conventional LED transferred to Si substrate (LED-C). In addition, the output power of GaP-dish LEDs was increased with the decrease of GaP-dish diameter. When the GaP-dish diameter decreased to 3 mu m, the output power reached 2.2 mW, which was two times higher than that of LED-C.
Output Power of AlGaInP Light Emitting Diode Improved by Double Roughening AlGaInP Surfaces
(2010)
Huang, Ping-Wei
;
Wu, YewChung Sermon
;
材料科學與工程學系
;
Department of Materials Science and Engineering
An AlGaInP-based vertical light emitting diode (LED) comprising double roughened (GaP and n-AlGaInP) surfaces and a bottom metal reflector was fabricated by surface-etching and wafer-bonding technologies. The roughened GaP surface was created by photolithography and wet etching, while the AlGaInP surface was roughened by inductively coupled plasma dry etching. The output power of the double roughened LED could reach 5.88 mW, which was 2.56 times higher than that of the conventional LED. This is because the double roughened surfaces can provide photons multiple chances to escape from the LED surface and can redirect photons.