TY - GEN
T1 - Fabrication of sub-micrometer surface structures on sapphire substrate for GaN-based light-emitting diodes by metal contact printing method
AU - Hsieh, Yi Ta
AU - Chen, Wei Ru
AU - Lin, An Ru
AU - Lee, Yung-Chun
AU - Lin, Hung Yi
PY - 2011/10/4
Y1 - 2011/10/4
N2 - Nano-scale pattern sapphire substrate (NPSS) used in light-emitting diodes (LEDs) was reported that could enhance their light extraction efficiency. This paper describes a novel method to fabricate sub-micrometer surface structures on sapphire substrate. This metal contact printing method can directly transferred a metal film pattern from a silicon mold to a sapphire substrate, and subsequently use the transferred metal film pattern as the etching mask for inductively coupled plasma (ICP) etching on the sapphire substrate. Because of excellent etching selectivity of the metal films, it is easy to obtain deeper etching depth on sapphire. Experimental tests have been successfully fabricated six different feature size hexagon surface structures on a 2 inch sapphire substrate and the etching depth is about 400 nm. The LED structures were grown on the patterned sapphire substrate by metal-organic chemical vapor deposition (MOCVD). The measurement forward voltages of the LEDs grown on different pattern size of the PSS were similar, and it is found that the luminous intensity was increasing with decreasing pattern size. It indicates that the pattern size of the PSS is related to the capability of light extraction, and the maximum increase intensity is 84.7% higher than conventional LEDs.
AB - Nano-scale pattern sapphire substrate (NPSS) used in light-emitting diodes (LEDs) was reported that could enhance their light extraction efficiency. This paper describes a novel method to fabricate sub-micrometer surface structures on sapphire substrate. This metal contact printing method can directly transferred a metal film pattern from a silicon mold to a sapphire substrate, and subsequently use the transferred metal film pattern as the etching mask for inductively coupled plasma (ICP) etching on the sapphire substrate. Because of excellent etching selectivity of the metal films, it is easy to obtain deeper etching depth on sapphire. Experimental tests have been successfully fabricated six different feature size hexagon surface structures on a 2 inch sapphire substrate and the etching depth is about 400 nm. The LED structures were grown on the patterned sapphire substrate by metal-organic chemical vapor deposition (MOCVD). The measurement forward voltages of the LEDs grown on different pattern size of the PSS were similar, and it is found that the luminous intensity was increasing with decreasing pattern size. It indicates that the pattern size of the PSS is related to the capability of light extraction, and the maximum increase intensity is 84.7% higher than conventional LEDs.
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U2 - 10.1109/NEMS.2011.6017451
DO - 10.1109/NEMS.2011.6017451
M3 - Conference contribution
AN - SCOPUS:80053304529
SN - 9781612847757
T3 - NEMS 2011 - 6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems
SP - 703
EP - 706
BT - NEMS 2011 - 6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems
T2 - 6th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, NEMS 2011
Y2 - 20 February 2011 through 23 February 2011
ER -