本論文主要是探討不同磊晶結構的高亮度氮化鎵發光二極體的光電特性。除了
提升氮化鎵發光二極體的亮度之外，在照明的應用上，發光二極體一直面臨著光電
轉換效率不佳的情形，也就是被稱為“掉落效應“的現象。該現象尤其嚴重發生於高
電流密度時，這樣的現象十分不利於發展照明用的高亮度氮化鎵發光二極體。一般
而言，載子結合率可由輻射結合機制與非輻射結合機制相互竸爭，因此有人認為非輻
射結合機制中的“歐傑效應“是造成掉落效應的主要因素，這種觀點也在現行的復合效
率模型中被考慮到。然而，現行的復合效率模型並不能很好的擬合實驗結果，因此必
然有部份的效率損失機制並未在傳統的復合效率模型被考慮到。為了提高模型的擬合
度，本研究亦針對復合效率模型進行了一些修正與推測以令其更為符合實驗結果。結
果發現，除了歐傑效應的影響之外，電子溢流與極化效應確實可能實際影響復合過
程。電子溢流的影響在於電子不能有效被侷限於量子井進而降低電子電洞的結合率，
尤其於高電流密度時，電子溢流之勢更趨嚴重。而極化效應則是探討材料本身，由於
晶格常數的不匹配，元件充滿著不均勻分佈的電場，因此能帶場被異常的拉扯，載
子的波函數也受到能帶的影響而分離，在高電流密度時，能帶的拉扯會更加嚴重，
因而減少電子電洞對復合的機會。因此本研究主要提出數種針對上述效率損失機制
作改善的結構來提升氮化鎵發光二極體的發光亮度與光電特性，包含磊晶結構的應
力調變、透過結構來減少載子溢流與提升量子井的內部發光效率。另外透過理論推
導，元件耗能也是影響發光效率很重要因素，因此，有效減少元件的順偏電壓必然
能改善整體的元件特性。為了提高氮化鎵發光二極體的發光效率，實驗上以各種具
有目的性的結構來比較其發光效益。具有高電子反射能力的“多重量子能障“結構被
放置於氮化鎵發光二極體用以減少電子溢流的現象。透過有效的提高電子反射率，
電子溢流減少，復合率增加且亮度提升，而由於多重量子能障結構的特殊性，整體結構之電阻值亦減少，明顯的掉落效應改善效果主要是歸因於復合率增加以及順偏
電壓減少的合併效應。除了實驗上的觀察，此實驗亦以數值模擬驗證以強化我們的論
點。另外一種方法是使用”階梯式電子注入層”來減速電子以達成減少電子溢流的效
果。在實驗的觀察上，階梯式電子注入層亦可以改善元件的光電特性，然而電子阻
擋層並不能被其取代，因為氮化鋁材料具有調節氮化鎵發光二極體應力的效果，失去
該層材料會使元件的光電特性受損。另外為了改善整體元件存在的不均勻應力，具
調節應力效果的結構也被導入以解決這個現象。由於應力影響最劇的部份在於主動
區的部份，主因就是來自於氮化銦鎵的晶格大於氮化鎵，故在其材料接面處產生異
常的電場。為了彌補這些變化，我們在其中放入了晶格較小的氮化鋁鎵來產生反向
的鍵結變化，因此預期可以減少原先異常電場的強度而減輕極化效應對元件的影
響。上述的各種實驗，其目的都是為了能讓高亮度氮化鎵發光二極體的光電特性更
加精進，尤其是改善掉落效應。

The different epitaxial structures of the high-brightness gallium nitride (GaN)
based light-emitting diodes (LEDs) are demonstrated in this dissertation. In addition
to enhancing the brightness of the devices in the lighting applications, LEDs face
the poor photoelectric conversion efficiency and this phenomenon is called "Droop
Effect". This phenomenon happens seriously at high current density, it goes against
the development of lighting for high brightness GaN-based LEDs. In general, the
recombination rate is composed of the radiative recombination mechanism and the
non-radiative recombination mechanism. Hence, some researches indicate that
Auger effect belongs to non-radiative recombination mechanism is the main root to
cause the efficiency droop effect. And this aspect is also included in current rate
equation. However, current rate equation does not agree well to experimental
results. Hence, there are must some efficiency loss mechanism not be considered
among traditional rate equation. For enhancing fitness results between model and
experimental data, we modify original rate equation and predict some physical
mechanisms to fit experimental data effectively. It is observed that in additional to
Auger effect, electrons overflow and polarization effect are also affect the carrier
recombination process actually. Electrons overflow may cause electrons not be
confined effectively in the quantum wells well thus reducing the electron-hole
recombination rate. Especially when devices are operated at high current density,
electrons overflow becomes severer. As for polarization effect is about the material
issue. Because of the lattice mismatch between the lattice constants, the device is
filled with non-uniform distribution electric field, so the energy band is bent
abnormally. Hence, wave function of carrier is separated by band bending affect. Especially at high current density, the separation will be more serious. Thus the
electron-hole recombination rate is reduced. For this reason, this research
proposes several epitaxial structures aiming at specific efficiency loss mechanism
to improve the brightness intensity and optical-electrical properties of GaN-based
LEDs. Including stress modulation for the epitaxial structure, mitigating electrons
overflow and enhancing the efficiency of internal quantum luminescing in the
quantum well. In addition, through theoretical deduction, energy consumption of
device was also a very important factor affects the luminous efficiency. Hence,
effectively reducing forward voltage of devices must be able to improve the overall
device characteristics. In order to improve the luminescing efficiency of GaN-based
LEDs that varies purposive comparisons among several experimental structures
has been achieved. “Multiple Quantum Barriers” (MQBs) structure with high
electron reflection capacity is placed in GaN-based LEDs for reducing the electron
overflow. Through effectively raising electron reflectance, the reducing electron
overflow and the increasing recombination rate enhance the brightness of the
device. On the other hand, special properties for MQBs structure causes lower
overall resistance of the device. Hence, obvious improvement for droop effect is
due to the combining effect of increasing recombination rate and reducing forward
voltage. In addition to the experimental observation, this experiment is also proofed
through theoretical analysis to enhance our arguments. Another way to reduce
electrons overflow effect is using “Staircase Electron Injector” (SEI) structure for
decelerating electrons. In the experimental observation, SEI is useful to enhance
improvement of electrical-optical properties for device. However, SEI can’t replace
electron blocking layer (EBL) in mitigating electrons overflow. Because of aluminum
gallium nitride (AlGaN) material may provide strain-compensation effect on GaN-based LEDs. Removing this material will damage electric and optical
properties of GaN-based devices. Further, in order to improve the non-uniform
stress distributed in whole device. The structure could modulate the stress is also
trying to solve this phenomenon. Because the most violent influence is present in
the active region, the main cause is attribute to the lattice constant of InGaN is
larger than which of GaN. So, abnormal electric field is present in the material
junction. In order to compensate those extra-electric fields, we put AlGaN with
smaller lattice constant in front of active region to produce the inverse change on
stress. It is expected that can reduce the abnormal electric field strength to alleviate
the polarization of GaN-based LEDs. Various experiments mention above all have
aim to achieve more sophisticated optical and electrical properties of
high-brightness GaN LEDs, in particular to improve droop effect.

Chapter 1
[1] S. Nakamura, M. Senoh, N. Iwasa, and S. Nagahama, “High-power InGaN
single-quantum-well-structure blue and violet light-emitting diodes,” Appl. Phys.
Lett., vol. 67, no. 13, pp. 1868–1870, 1995.
[2] S. J. Chang, W. C. Lai, Y. K. Su, J. F. Chen, C. H. Liu, and U. H. Liaw,
“InGaN/GaN multiquantum well blue and green light emitting diodes,” IEEE J.
Sel. Topics Quantum Electron., vol. 8, no. 2, pp. 278–283, Mar./Apr. 2002.
[3] Y. J. Lee, et al., “Enhancing the output power of GaN-based LEDs grown on
wet-etched patterned sapphire substrates, ” IEEE Photon. Technol. Lett., vol. 18,
no. 10, pp. 1152–1154, May 15, 2006.
[4] S. J. Chang, et al., “Nitride-based light emitting diodes with indium tin oxide
electrode patterned by imprint lithography,” Appl. Phys. Lett., vol. 91, no. 1, pp.
013504-1–013504-3, 2007.
[5] S. J. Chang, C. H. Chen, P. C. Chang, Y. K. Su, P. C. Chen, Y. D. Jhou, 317 H.
Hung, C. M. Wang, and B. R. Huang, “Nitride-based LEDs with p-InGaN
capping layer,” IEEE Tran. Electron. Devices, vol. 50, no. 12, pp. 2567–2570,
Dec. 2003. 320
[6] C. F. Shen, S. J. Chang, T. K. Ko, C. T. Kuo, S. C. Shei, W. S. Chen, C. T. Lee, C.
S. Chang, and Y. Z. Chiou, “Nitride-based light emitting diodes with textured
sidewalls and pillar waveguides,” IEEE Photon. Technol. Lett., vol. 18, no. 23,
pp. 2517–2519, Dec. 2006.
[7] K. Akita, T. Kyono, Y. Yoshizumi, H. Kitabayashi, and K.
Katayama,“Improvements of external quantum efficiency of InGaN-based blue
light-emitting diodes at high current density using GaN substrates,” J. Appl. Phys., vol. 101, no. 3, pp. 033104-1–033104-5, 2007.
[8] A. Y. Kim, W. Götz, D. A. Steigerwald, J. J. Wierer, N. F. Gardner, J. Sun, S. A.
Stockman, P. S. Martin, M. R. Krames, R. S. Kern, and F. M. Steranka,
“Performance of high-power AlInGaN light emitting diodes,” Phys. Status Solidi
A, vol. 188, no. 1, pp. 15–21, 2001.
[9] A. A. Efremov, N. I. Bochkareva, R. I. Gorbunov, D. A. Larinovich, Y. T. Rebane,
D. V. Tarkhin, and Y. G. Shreter, “Effect of the joule heating on the quantum
efficiency and choice of thermal conditions for high-power blue InGaN/GaN
LEDs,” Semiconductors, vol. 40, no. 5, pp. 605–610, 2006.
[10] C. H. Wang, D. W. Lin, C. Y. Lee, M. A. Tsai, G. L. Chen, H. T. Kuo, W. H. Hsu,
H. C. Kuo, T. C. Lu, S. C. Wang, and G. C. Chi, “Efficiency and droop
improvement in GaN-based high-voltage light- emitting diodes,” IEEE Electron.
Device Lett., vol. 32, no. 8, pp. 1098–1100, Aug. 2011.
Chapter 2
[1] S. Nakamura, M. Senoh, S. I. Nagahama, N. Iwasa, T. Yamada, T. Matsushita, H.
Kiyoku and Y. Sugimoto, “InGaN-Based Multi-Quantum-Well-Structure Laser
Diodes”, Jpn. J. Appl. Phys., Vol. 35, pp. L74-L76, 1997.
[2] H. Amano, M. Kito, K. Hiramatsu and I. Akasaki, “P-Type Conduction in
Mg-Doped GaN Treated with Low-Energy Electron Beam Irradiation (LEEBI)”,
Jpn. J. Appl. Phys., Vol. 28, pp. L2112-L2114, 1989.
[3] S. Nakamura, T. Mukai, M. Senoh and N. Iwasa, ” Thermal Annealing Effects on
P-Type Mg- Doped GaN Films”, Jpn. J. Appl. Phys., Vol. 31, pp. L139-L141,
1992.
[4] I. Akasaki and Hiroshi, “Breakthroughs in Improving Crystal Quality of GaN and
Invention of the p–n Junction Blue-Light-Emitting Diode”, Jpn. J. Appl. Phys.,Vol.
45, No. 12, 2006, pp. 9001-9010.
[5] S. Nakamura, M. Senoh, N. Iwasa and S.I. Nagahama, “High-Brightness InGaN
Blue, Green and Yellow Light-Emitting Diodes with Quantum Well Structures”,
Jpn. J. Appl. Phys., Vol.34, L797-L799, 1995.
[6] C. H. Ko, Y. K. Su, S. J. Chang, T. M. Kuan, C. I. Chiang, W. H. Lan, W. J. Lin
and J. Webb, “P-Down InGaN/GaN Multiple Quantum Wells Light-Emitting
Diode Structure Grown by Metal-Organic Vapor-Phase Epitaxy”, Jpn. J. Appl.
Phys., Vol. 41, 2489-2492, 2002.
[7] T. C. Wen and W. I. Lee, “Influence of Barrier Growth Temperature on the
Properties of InGaN/GaN Quantum Well”, Jpn. J. Appl. Phys., Vol. 40,
5302-5303, 2001.
[8] J. K Sheu, C. J Pan, G. C. Chi, C. H. Kuo, L. W Wu, C. H. Chen, S. J. Chang and Y. K. Su, “White-light emission from InGaN-GaN multi quantum-well
light-emitting diodes with Si and Zn codoped active well layer”, IEEE Photon.
Technol. Lett., Vol. 14, No. 4, pp. 450-452, 2002.
[9] R. Davis, A. Roskowski, E. Preble, J. Speck, B. Heying, J. Freitas, E. Glaser,
and W. Carlos, “Gallium nitride materials - progress, status, and potential
roadblocks “, Proc. IEEE 90, 993, 2002.
[10] C. S. Chang, S. J. Chang, Y. K. Su, C. T. Lee, Y. C. Lin, W. C. Lai, S. C. Shei, J.
C. Ke and H. M. Lo, “Nitride-based LEDs with textured side walls”, IEEE
Photon. Technol. Lett., Vol. 16, pp. 750-752, 2004
[11] S. J. Chang, C. H. Chen, P. C. Chang, Y. K. Su, P. C. Chen, Y. D. Jhou, H.
Hung, S. M. Wang and B. R. Huang, “Nitride-based LEDs with p-InGaN
capping layer”, IEEE Tran. Electron. Dev., Vol. 50, pp. 2567-2370, 2003
[12] C. Y. Chang, S. J. Chang, C. H. Liu, S. G. Li and T. K. Lin, "GaN-based LEDs
with double strain releasing MQWs and Si delta-doping layers", IEEE Photon.
Technol. Lett., Vol. 24, pp. 1809-1811, 2012.
[13] S. J. Chang, C. S. Chang, Y. K. Su, R. W. Chuang, Y. C. Lin, S. C. Shei, H. M.
Lo, H. Y. Lin and J. C. Ke, "Highly reliable nitride based LEDs with SPS+ITO
upper contacts", IEEE J. Quan. Electron., Vol. 39, pp. 1439-1443, 2003.
[14] H.B. Bebb and E.W. Williams, “Photoluminescence I: Theory,” in
Semiconductors and Semimetals (R.K. Willardson and A.C. Beer, eds.)
Academic Press, New York, 8, 181–320, 1972; E.W. Williams and H.B. Bebb,
“Photoluminescence II: Gallium Arsenide,” ibid. 321–392.
[15] P.J. Dean, “Photoluminescence as a Diagnostic of Semiconductors,” Prog.
Crystal Growth Charact. 5, 89–174, 1982.
[16] Q. Zhong, D. Inniss, K. Kjoller, and V.B. Elings, “Fractured Polymer/Silica Fiber Surface Studied by Tapping Mode Atomic Force Microscopy,” Surf. Sci. Lett.
290, L668–L692, 1993.
[17] C.V. Raman and K.S. Krishna, “A New Type of Secondary Radiation,” Nature
121, 501–502, March 1928.
[18] D.A. Long, Raman Spectroscopy, McGraw-Hill, New York, 1977.
[19] K. Y. Zang, Y. D. Wang, S. J. Chua, L. S. Wang, S. Tripathy and C. V.
Thompson, “Nanoheteroepitaxial lateral overgrowth of GaN on nanoporous
Si(111)”, Appl. Phys. Lett., Vol. 88, Art. no. 141925, 2006.
Chapter 3
[1] M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek, and Y.
Park, “Origin of efficiency droop in GaN-based light-emitting diodes”, Appl. Phys.
Lett. 91, 183507, 2007.
[2] Q. Dai, Q. Shan, J. Wang, S. Chhajed, J. Cho, E. F. Schubert, M. H. Crawford, D.
D. Koleske, M.-H. Kim, and Y. Park, “Carrier recombination mechanisms and
efficiency droop in GaInN/GaN light-emitting diodes”, Appl. Phys. Lett. 97,
133507, 2010.
[3] J. Xie, X. Ni, Q. Fan, R. Shimada, Ü . Ö zgür, and H. Morkoç, “On the efficiency
droop in InGaN multiple quantum well blue light emitting diodes and its
reduction with p-doped quantum well barriers”, Appl. Phys. Lett. 93,
121107 ,2008.
[4] A. Y. Kim, W. Götz, D. A. Steigerwald, J. J. Wierer, N. F. Gardner, J. Sun, S. A.
Stockman, P. S. Martin, M. R. Krames, R. S. Kern, and F. M. Steranka,
“Performance of High-Power AlInGaN Light Emitting Diodes", Phys. Status
Solidi A 188, 15, 2001.
[5] Y. C. Shen, G. O. Mueller, S. Watanabe, N. F. Gardner, A. Munkholm, and M. R.
Krames, “Auger recombination in InGaN measured by photoluminescence”,
Appl. Phys. Lett. 91, 141101, 2007.
[6] M. Zhang, P. Bhattacharya, J. Singh, and J. Hinckley, “Direct measurement of
auger recombination in In0.1Ga0.9N/GaN quantum wells and its impact on the
efficiency of In0.1Ga0.9N/GaN multiple quantum well light emitting diodes”, Appl.
Phys. Lett. 95, 201108, 2009.
[7] A. David and M. J. Grundmann, “Droop in InGaN light-emitting diodes: A differential carrier lifetime analysis”, Appl. Phys. Lett. 96, 103504, 2010.
[8] J. Hader, J. V. Moloney, B. Pasenow, S. W. Koch, M. Sabathil, N. Linder, and S.
Lutgen, “On the importance of radiative and Auger losses in GaN-based
quantum wells”, Appl. Phys. Lett. 92, 261103, 2008.
[9] K. J. Vampola, M. Iza, S. Keller, S. P. DenBaars, and S. Nakamura,
“Measurement of electron overflow in 450 nm InGaN light-emitting diode
structures”, Appl. Phys. Lett. 94, 061116, 2009.
[10] J. Hader, J. V. Moloney, and S. W. Koch, “Density-activated defect
recombination as a possible explanation for the efficiency droop in
GaN-based diodes”, Appl. Phys. Lett. 96, 221106, 2010.
[11] A. Hangleiter, International Conference on Nitride Semiconductors (ICNS),
Jeju, Korea, 18–23 October 2009.
[12] H. Y. Ryu, K. H. Ha, J. K. Son, S. N. Lee, H. S. Paek, T. Jang, Y. J. Sung, K. S.
Kim, H. K. Kim, Y. Park, and O. H. Nam, “Determination of internal parameters
in blue InGaN laser diodes by the measurement of cavity-length dependent
characteristics”, Appl. Phys. Lett. 93, 011105, 2008.
[13] H.-Y. Ryu, H.-S. Kim, and J.-I. Shim, “Rate equation analysis of efficiency
droop in InGaN light-emitting diodes”, Appl. Phys. Lett. 95, 081114, 2009.
[14] S. L. Chuang and C. S. Chang, “k⋅p method for strained wurtzite
semiconductors”, Phys. Rev. B 54, 2491,1996.
[15] I. Vurgaftman and J. R. Meyer, “Band parameters for nitrogen-containing
semiconductors”, J. Appl. Phys. 94, 3675, 2003.
[16] Y. P. Varshni, “Temperature dependence of the energy gap in semiconductors”,
Physica 34, 149, 1967.
[17] K. Osamura, S. Naka, and Y. Murakami, “Preparation and optical properties of Ga1-xInxN thin films”, J. Appl. Phys. 46, 3432, 1975.
[18] M. E. Aumer, S. F. LeBoeuf, F. G. McIntosh, and S. M. Bedair, “High optical
quality AlInGaN by metalorganic chemical vapor deposition”, Appl. Phys. Lett.
75, 3315, 1999.
[19] C. G. Van de Walle and J. Neugebauer, “Universal alignment of hydrogen
levels in semiconductors, insulators and solutions”, Nature 423, 626, 2003.
[20] V. Fiorentini, F. Bernardini, and O. Ambacher, “Evidence for nonlinear
macroscopic polarization in III–V nitride alloy heterostructures”, Appl. Phys.
Lett. 80, 1204, 2002.
[21] J. P. Ibbetson, P. T. Fini, K. D. Ness, S. P. DenBaars, J. S. Speck, and U. K.
Mishra, “Polarization effects, surface states, and the source of electrons in
AlGaN/GaN heterostructure field effect transistors”, Appl. Phys. Lett. 77, 250,
2000.
[22] S. F. Chichibu, A. C. Abare, M. S. Minsky, S. Keller, S. B. Fleischer, J. E.
Bowers, E.Hu,U. K. Mishra, L. A. Coldren, S. P. DenBaars, and T. Sota,
“Effective band gap inhomogeneity and piezoelectric field in InGaN/GaN
multiquantum well structures”, Appl. Phys. Lett. 73, 2006, 1998.
[23] C. M. Caughey and R. E. Thomas, Proc. “Carrier mobilities in silicon
empirically related to doping and field”,IEEE 55, 2192, 1967.
[24] M. Farahmand et al. “Monte Carlo simulation of electron transport in the
III-nitride wurtzite phase materials system: binaries and ternaries”, IEEE Trans.
Electron Devices 48, 535, 2001.
Chapter 4
[1] S. Grzanka, et al., “Role of the electron blocking layer in the lowtemperature
collapse of electroluminescence in nitride light-emitting diodes,” Appl. Phys.
Lett., vol. 90, no. 10, pp. 103507-1–103507-3, 2007.
[2] K. Iga, H. Uenohara, and F. Koyama, “Electron reflectance of multiquantum
barrier (MQB),” Electron. Lett., vol. 22, no. 19, pp. 1008–1009, 1986.
[3] T. Takagi, F. Koyama, and K. Iga, “Modified multiquantum barrier for 600nm
range AlGaInP lasers”, Electron Lett., vol. 27, pp. 1081-1082, 1991.
[4] T. Takagi, F. Koyama, and K. Iga, “Design and photoluminescence study on a
multiquantum barrier”, IEEE J. quantum Electron., vol. 27, pp. 1511-1519,
1991.
[5] S. T. Yen, C. M. Tsai, C. P. Lee, and D. C. Liu, “Enhancement of electron-wave
reflection by superlattices with multiple stacks of multiquantum barriers”, Appl.
Phys. Lett., vol. 64, pp. 1108-1110, 1994.
[6] F. Capasso, in Semiconductors and semimetals, R. K. Willardson and A. C.
Beer, Ed. New Yoke: Academic, vol. 24, pp.319, 1987.
[7] K. K. urihara, T. Numai, I. Ogura, A. Yasuda, M. Sugimoto, and K. Kasahara,
“Reduction of series resistance of the distributed Bragg reflector in vertical
cavities by using quasi-graded superlattices at the heterointerfaces”, J. Appl.
Phys., vol. 73, pp.21-27, 1993.
[8] F. Y. Huang, T. C. Shen, and H. Morkoc, “Quantum tunneling of electrons
through superlattices in metal-semiconductor ohmic contacts”, Solid State
Electron., vol. 36, pp. 1375-1378, 1993.
[9] T. Takagi, F. Koyama, and K. Iga, “Electron-wave reflection by multi-quantum barrier in n-GaAs/i-GaAs/i-AlGaAs/n-GaAs tunneling diode”, Appl. Phys. Lett.,
vol. 59, pp. 2877-2879, 1991.
[10] S. T. Yen, C. P. Lee, C. M. Tsai, and D. C. Liu, “Influence of X-valley
superlattice on electron blocking by multiquantum barrier”, Appl. Phys. Lett.,
vol.65, pp. 2720-2722, 1994.
[11] K. Iga, H. Uenohara, and F. Koyama, “Electron reflectance of multiquantum
barrier (MQB)”, Electron. Lett., vol. 22, no. 19, pp. 1008-1010, Sept. 1986
[12] S. H. Yen, M. C. Tsai, M. L. Tsai, Y. J. Shen, T. C. Hsu, and Y. K. Kuo, “Effect
of N-type AlGaN layer on carrier transportation and efficiency droop of blue
InGaN light-emitting diodes,” IEEE Photon. Technol. Lett., vol. 21, no. 14, pp.
975–977, Jul. 2009.
[13] A. David, M. J. Grundmann, J. F. Kaeding, N. F. Gardner, T. G. Mihopoulos,
and M. R. Krames, “Carrier distribution in (0001)InGaN/GaN multiple quantum
well light-emitting diodes,” Appl. Phys. Lett., vol. 92, no. 5, pp.
053502-1–053502-3, 2008.
[14] C. S. Chang, Y. K. Su, S. J. Chang, P. T. Chang, Y. R. Wu, K. H. Huang, and T.
P. Chen, “High-brightness AlGaInP 537-nm light-emitting diode with a chirped
multi- quantum barrier,” IEEE J. Quantum Electon., vol. 34, no. 1, pp. 77–83,
Jan. 1988.
[15] X. Ni, X. Li, J. Lee, S. Liu, Ü . Ö zgür, H. Morkoç, A. Matulionis, T. Paskova, G.
Mulholland, and K. R. Evans, “The effect of ballistic and quasi-ballistic
electrons on the efficiency droop of InGaN light emitting diodes”, Phys. Status
Solidi (RRL) 4, 194, 2010.
[16] C. S. Chang, et al., “Nitride-based LEDs with textured side walls,” IEEE
Photon. Technol. Lett., vol. 16, no. 3, pp. 750–752, Mar. 2004.
[17] S. J. Chang, C. H. Chen, P. C. Chang, Y. K. Su, P. C. Chen, Y. D. Jhou, H.
Hung, S. M. Wang and B. R. Huang, “Nitride-based LEDs with p-InGaN
capping layer”, IEEE Tran. Electron. Dev., Vol. 50, pp. 2567-2370, 2003
[18] C. Y. Chang, S. J. Chang, C. H. Liu, S. G. Li and T. K. Lin, "GaN-based LEDs
with double strain releasing MQWs and Si delta-doping layers", IEEE Photon.
Technol. Lett., Vol. 24, pp. 1809-1811, 2012.
[19] S. J. Chang, C. S. Chang, Y. K. Su, R. W. Chuang, Y. C. Lin, S. C. Shei, H. M.
Lo, H. Y. Lin and J. C. Ke, "Highly reliable nitride based LEDs with SPS+ITO
upper contacts", IEEE J. Quan. Electron., Vol. 39, pp. 1439-1443, 2003.
[20] J. K. Sheu, G. C. Chi and M. J. Jou, "Enhanced output power in an InGaN-GaN
multiquantum-well light-emitting diode with an InGaN current-spreading layer",
IEEE Photon. Technol. Lett., Vol. 13, pp. 1104-1106, 2001.
[21] C. H. Chen, Y. K. Su, S. J. Chang, G. C. Chi, J. K. Sheu, J. F. Chen, C. H. Liu
and U. H. Liaw, "High brightness green light emitting diode with charge
asymmetric resonance tunneling structure", IEEE Electron. Dev. Lett., Vol. 23,
pp. 130-132, 2002.
[22] C. H. Chen, S. J. Chang, Y. K. Su, G. C. Chi, J. K. Sheu and J. F. Chen, "High
efficient InGaN/GaN MQW green light emitting diodes with CART and DBR
structures", IEEE J. Sel. Top. Quan. Electron., Vol. 8, pp. 284-288, 2002.
[23] W. C. Lai, S. J. Chang, M. Yokoyama, J. K. Sheu and J. F. Chen,
"InGaN/AlInGaN light emitting diodes", IEEE Photon. Technol. Lett., Vol. 13,
pp. 559-561, 2001.
[24] S. C. Ling, T. C. Lu, S. P. Chang, J. R. Chen, H. C. Kuo and S. C. Wang, “Low
efficiency droop in blue-green m-plane InGaN/GaN light emitting diodes”, Appl.
Phys. Lett., Vol. 96, Art. no. 231101, 2010.
[25] H. P. Zhao, R. A. Arif, Y. K. Ee and N. Tansu, “Self-consistent analysis of
strain-compensated InGaN-AlGaN quantum wells for lasers and light-emitting
diodes”, IEEE J. Quan. Electron., Vol. 45, pp. 66-78, 2009.
[26] http://222.66.64.131:8080/sdzg_admin/upload/myupload_2115.pdf
[27] L. A. Falkovsky, W. Knap, J. C. Chervin and P. Wisniewski, “Phonon modes
and metal-insulator transition in GaN crystals under pressure”, Phys. Rev. B,
Vol. 57, pp. 11349-11355, 1998.
[28] K. Y. Zang, Y. D. Wang, S. J. Chua, L. S. Wang, S. Tripathy and C. V.
Thompson, “Nanoheteroepitaxial lateral overgrowth of GaN on nanoporous
Si(111)”, Appl. Phys. Lett., Vol. 88, Art. no. 141925, 2006.