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Comparison of InGaN-Based LEDs
Grown on Conventional Sapphire and
Cone-Shape-Patterned Sapphire Substrate
Jae-Hoon Lee, Senior Member, IEEE, Dong-Yul Lee, Bang-Won Oh, and Jung-Hee Lee, Senior Member, IEEE
IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 57, NO. 1, JANUARY 2010
D.J. Sun
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Outline
• Introduction
• Experiment
• Results and discussion
• Conclusion
• References
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Introduction
• In this paper, we report a remarkable improvement in
the electrical and optical properties of InGaN/GaN
LEDs grown on a cone-shape-patterned sapphire
substrate (CSPSS) by finding the difference between
the growth mode on a CSPSS and a conventional
sapphire substrate (CSS).
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Experiment
Cr/Au
ITO
p-GaN(150nm)
InGaN：3nm
Si-doped GaN：12nm
Mg-AlGaN/GaN
MQW four-period
Cr/Au
n-GaN
GaN buffer layer at 550℃ (25nm)
Sapphire (2-inch)
chip size：260×690µm²
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Experiment
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Experiment
Diameter：3µm
Interval： 1µm
Height： 1.5µm
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Results and discussion
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Results and discussion
Sapphire
Sapphire
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Results and discussion
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Results and discussion
Dark spot density：7 ×108 cm-2
Dark spot density：2×108 cm-2
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