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Characterization study of GaN-based epitaxial layer and light-emitting diode on nature-patterned sapphire substrate

Published online by Cambridge University Press:  06 February 2012

H.Y. Lin ,
Y.J. Chen ,
C.L. Chang ,
X.F. Li ,
C.H. Kuo ,
S.C. Hsu  and
C.Y. Liu
H.Y. Lin
Affiliation:
Department of Chemical and Materials Engineering, National Central University, Jhongli City, Taiwan 32001, Republic of China
Y.J. Chen
Affiliation:
Department of Chemical and Materials Engineering, National Central University, Jhongli City, Taiwan 32001, Republic of China
C.L. Chang
Affiliation:
Department of Chemical and Materials Engineering, National Central University, Jhongli City, Taiwan 32001, Republic of China
X.F. Li
Affiliation:
Department of Chemical and Materials Engineering, National Central University, Jhongli City, Taiwan 32001, Republic of China
C.H. Kuo
Affiliation:
Institute of Lighting and Energy Photonics, National Chiao Tung University, Tainan City, Taiwan 30010, Republic of China
S.C. Hsu
Affiliation:
Department of Chemical and Materials Engineering, Tamkang University, New Taipei City, Taiwan 25137, Republic of China
C.Y. Liu*
Affiliation:
Department of Chemical and Materials Engineering, National Central University, Jhongli City, Taiwan 32001, Republic of China
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Chemical wet etching on c-plane sapphire wafers by three etching solutions (H3PO4, H2SO4, and H3PO4/H2SO4 mixing solution) was studied. Among these etching agents, the mixing H3PO4/H2SO4 solution has the fastest etching rate (1.5 μm/min). Interestingly, we found that H2SO4 does not etch the c-plane sapphire wafer in thickness; instead, a facet pyramidal pattern is formed on the c-plane sapphire wafer. GaN light-emitting diode (LED) epitaxial structure was grown on the sapphire wafer with the pyramidal pattern and the standard flat sapphire wafer. X-ray diffraction and photoluminescence measurement show that the pyramidal pattern on the sapphire wafer improved crystalline quality but augmented the compressive stress level in the GaN LED epilayer. The horizontal LED chips fabricated on the pyramidal-patterned sapphire wafer have a larger light output than the horizontal LED chips fabricated on the standard flat sapphire wafer by 20%.

Keywords

III–VSemiconducting
Type
Articles
Information
Journal of Materials Research , Volume 27 , Issue 6 , 28 March 2012 , pp. 971 - 977
Copyright
Copyright © Materials Research Society 2012

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References

REFERENCES

1.Koike, M., Shibata, N., Kato, H., and Takahashi, Y.: Development of high efficiency GaN-based multiquantum-well light-emitting diodes and their applications. IEEE J. Sel. Top. Quantum Electron. 8, 271 (2002).CrossRefGoogle Scholar
2.Lydecker, S.H., Leadford, K.F., and Ooyen, C.A.: Lighting industry acceptance of solid state lighting. Proc. SPIE Int. Soc. Opt. Eng. 5187, 22 (2004).Google Scholar
3.LEDs Magazine, December 21, 2006. Available athttp://ledsmagazine.com/news/3/12/19/1.Google Scholar
4.Narukawa, Y., Narita, J., Sakamoto, T., Deguchi, K., Yamada, T., and Mukai, T.: Ultra-high efficiency white light emitting diodes. Jpn. J. Appl. Phys. 45, L1084 (2006).CrossRefGoogle Scholar
5.Lee, Y.J., Kuo, H.C., Lu, T.C., Su, B.J., and Wang, S.C.: Fabrication and characterization of GaN-Based LEDs grown on chemical wet-etched patterned sapphire substrates. J. Electrochem. Soc. 153(12), G1111 (2006).CrossRefGoogle Scholar
6.Wuu, D.S., Wang, W.K., Shih, W.C., Horng, R.H., Lee, C.E., Lin, W.Y., and Fang, J.S.: Enhanced output power of near-ultraviolet InGaN-GaN LEDs grown on patterned sapphire substrates. IEEE Photonics Technol. Lett. 17, 288 (2005).CrossRefGoogle Scholar
7.Yamada, M., Mitani, T., Narukawa, Y., Shioji, S., Niki, I., Sonobe, S., Deguchi, K., Sano, M., and Mukai, T.: InGaN-based near-ultraviolet and blue-light-emitting diodes with high external quantum efficiency using a patterned sapphire substrate and a mesh electrode. Jpn. J. Appl. Phys. 41, L1431 (2002).CrossRefGoogle Scholar
8.Feng, Z.H. and Lau, K.M.: Enhanced luminescence from GaN-based blue LEDs grown on grooved sapphire substrates. IEEE Photonics Technol. Lett. 17, 1812 (2005).CrossRefGoogle Scholar
9.Tadatomo, K., Okagawa, H., Ohuchi, Y., Tsunekawa, T., Imada, Y., Kato, M., and Taguchi, T.: High output power InGaN ultraviolet light-emitting diodes fabricated on patterned substrates using metalorganic vapor phase epitaxy. Jpn. J. Appl. Phys. 40(Pt 2), L583 (2001).CrossRefGoogle Scholar
10.Lee, Y.J., Tseng, H.C., and Kuo, H.C.: Improvement in light-output efficiency of AlGaInP LEDs fabricated on stripe patterned epitaxy. IEEE Photonics Technol. Lett. 17(12), 2532 (2005).CrossRefGoogle Scholar
11.Chen, J.J., Su, Y.K., Lin, C.L., Chen, S.M., Li, W.L., and Kao, C.C.: Enhanced output power of GaN-based LEDs with nano-patterned sapphire substrates. IEEE Photonics Technol. Lett. 20(13), 1193 (2008).CrossRefGoogle Scholar
12.Tsai, P.C., Ricky, W., and Su, Y.K.: Lifetime tests and junction-temperature measurement of InGaN light-emitting diodes using patterned sapphire substrates. J. Lightwave Technol. 25(2), 591 (2007).CrossRefGoogle Scholar
13.Wuu, D.S., Wang, W.K., Wen, K.S., Huang, S.C., Horng, R.H., Yu, Y.S., and Pan, M.H.: Fabrication of pyramidal patterned sapphire substrates for high-efficiency InGaN-based light emitting diodes. J. Electrochem. Soc. 153(8), G765 (2006).CrossRefGoogle Scholar
14.Dwikusuma, F., Saulys, D., and Kuech, T.F.: Study on sapphire surface preparation for III-nitride heteroepitaxial growth by chemical treatments. J. Electrochem. Soc. 149(11), G603 (2002).CrossRefGoogle Scholar
15.Simon, J., Langer, R., Barski, A., and Pelekanos, N.T.: Spontaneous polarization effects in GaN/AlxGa1-xN quantum wells. Phys. Rev. B 61, 7211 (2000).CrossRefGoogle Scholar
16.Li, Y.L., Huang, Y.R., and Lai, Y.H.: Efficiency droop behaviors of InGaN/GaN multiple-quantum-well light-emitting diodes with varying quantum well thickness. Appl. Phys. Lett. 91, 181113 (2007).CrossRefGoogle Scholar
17.Törmä, P.T., Svensk, O., Ali, M., Suihkonen, S., Sopanen, M., Odnoblyudov, M.A., and Bougrov, V.E.: Maskless roughening of sapphire substrates for enhanced light extraction of nitride based blue LEDs. Solid-State Electron. 53, 166 (2009).CrossRefGoogle Scholar
18.Zhao, D.G., Jiang, D.S., Zhu, J.J., Liu, Z.S., Wang, H., Zhang, S.M., Wang, Y.T., and Yang, H.: Role of edge dislocation and Si impurity in linking the blue luminescence and yellow luminescence in n-type GaN films. Appl. Phys. Lett. 95, 041901 (2009).CrossRefGoogle Scholar
19.Lee, J.H., Oh, J.T., Kim, Y.C., and Lee, J.H.: Stress reduction and enhanced extraction efficiency of GaN-based LED grown on cone-shape-patterned sapphire. IEEE Photonics Technol. Lett. 20(18), 1563 (2008).CrossRefGoogle Scholar