Browsing by Author "Yu, P. C."

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Design of Highly Absorption Structure by Flatted ITO Patterned Substrate for Thin Film a-Si Solar Cells
(2012)
Han, H. V.
;
Shih, H. S.
;
Chen, H. C.
;
Tsai, Y. L.
;
Yu, P. C.
The patterned substrate is a flatted structure which composed with two materials to enhance the absorption of a-Si solar cell. We optimized this structure by simulation method and find it has good omnidirectional antireflection effect. (C) 2012 Optical Society of America
Efficiency enhancement of UV/blue light emitting diodes via nanoscaled epitaxial lateral overgrowth of GaN on a SiO(2) nanorod-array patterned sapphire substrate
(2008-11-15)
Chiu, C. H.
;
Li, Zhen-Yu
;
Chao, C. L.
;
Lo, M. H.
;
Kuo, H. C.
High-quality GaN layer was successfully grown on a SiO(2) nanorod-array patterned sapphire substrate (NAPSS) using metal-organic chemical vapor deposition by a nanoscaled epitaxial lateral overgrowth (NELO) method. From tunneling electron microscope images, well coalescence and turned dislocations are parallel to the surface direction were clearly observed. The Raman shift measurement shows the residual stress in GaN was greatly reduced from 1.359 to 0.652 GPa when compared to a GaN on flat sapphire substrate. Also, a high-efficiency GaN-based light-emitting diodes (LEDs) were demonstrated on the NELO NAPSS GaN, the respective output power and external quantum efficiency of the NELO NAPSS LEDs were estimated to be 22 mW and 40.2% at an injection current of 20 mA, showing an enhancement factor of 52% over conventional LEDs. The significant improvement resulted from both the enhanced light extraction assisted by the NAPSS, and the reduced dislocation densities using the NELO method. (c) 2008 Published by Elsevier B.V.
Efficiency enhancement of UV/blue light emitting diodes via nanoscaled epitaxial lateral overgrowth of GaN on a SiO2 nanorod-array patterned sapphire substrate
(2008-11-15)
Chiu, C. H.
;
Li, Zhen-Yu
;
Chao, C. L.
;
Lo, M. H.
;
Kuo, H. C.
High-quality GaN layer was successfully grown on a SiO2 nanorod-array patterned sapphire substrate (NAPSS) using metal-organic chemical vapor deposition by a nanoscaled epitaxial lateral overgrowth (NELO) method. From tunneling electron microscope images, well coalescence and turned dislocations are parallel to the surface direction were clearly observed. The Raman shift measurement shows the residual stress in GaN was greatly reduced from 1.359 to 0.652 GPa when compared to a GaN on flat sapphire substrate. Also, a high-efficiency GaN-based light-emitting diodes (LEDs) were demonstrated on the NELO NAPSS GaN, the respective output power and external quantum efficiency of the NELO NAPSS LEDs were estimated to be 22 mW and 40.2% at an injection current of 20 mA, showing an enhancement factor of 52% over conventional LEDs. The significant improvement resulted from both the enhanced light extraction assisted by the NAPSS, and the reduced dislocation densities using the NELO method. (c) 2008 Published by Elsevier B.V.
Low cost high-efficiency high-density-plasma Silicon-based thin film solar cells with high light-soaking stability
(2012)
Hsiao, T. H.
;
Shieh, J. M.
;
Yu, P. C.
;
Shen, C. H.
;
Kao, M. H.
We investigate the performance of a single-junction amorphous Si (a-Si) and a-Si/a-Si tandem solar cells fabricated with Inductively Coupled Plasma (ICP) deposition technique. The high-density plasma resulting from high dissociation capacity of ICP enables good-quality hydrogenated Si films to be synthesized at low temperatures. High-density ICP also promotes the diffusion of reactive radicals on substrates and forms a-Si:H films with low defect density. We demonstrate single-junction a-Si solar cells and a-Si/a-Si tandem solar cell with a conversion efficiency of 9.6% and 8.8%, respectively. Highly light-soaking stable high-density plasma-fabricated a-Si and a-Si/a-Si solar cells were demonstrated with photo-induced degradation in conversion-efficiency as low as 7% and 5%, respectively.