Improvement of blue InGaN light-emitting diodes with gradually increased barrier heights from n- to p-layers

doi:10.1007/s12200-013-0342-x

Front Optoelec

2013, Vol. 6

Issue (4) : 429-434 https://doi.org/10.1007/s12200-013-0342-x

RESEARCH ARTICLE

Improvement of blue InGaN light-emitting diodes with gradually increased barrier heights from n- to p-layers

Wu TIAN, Xiong HUI(

), Yang LI, Jiangnan DAI, Yanyan FANG, Zhihao WU, Changqing CHEN

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China

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Abstract

The advantages of blue InGaN light-emitting diodes (LED) with the active region of gradually increased barrier heights from n- to p-layers are studied. The energy band diagram, hole concentration, electrostatic field near the electron blocking layer (EBL), and the internal quantum efficiency (IQE) are investigated by Crosslight simulation program. The simulation results show that the structure with gradually increased barrier heights has better performance over the equal one, which can be attributed to the mitigated polarization effect near the interface of the last barrier/EBL due to less interface polarization charges. Moreover, reduced barrier height toward the n-layers is beneficial for holes injection and transportation in the active region. As a result, holes are injected into the active region more efficiently and distributed uniformly in the quantum wells, with which both the IQE and the total lighting power are increased. Although it can lead to the broadening of the spontaneous emission spectrum, the increase is slight such that it has little effect on the application in solid-state lighting.

Keywords InGaN light-emitting diodes (LED) polarization effect gradual barrier height

Corresponding Author(s): HUI Xiong,Email:hsiung.hust@gmail.com

Issue Date: 05 December 2013

Cite this article:

Wu TIAN,Xiong HUI,Yang LI, et al. Improvement of blue InGaN light-emitting diodes with gradually increased barrier heights from n- to p-layers[J]. Front Optoelec, 2013, 6(4): 429-434.

URL:

https://academic.hep.com.cn/foe/EN/10.1007/s12200-013-0342-x
https://academic.hep.com.cn/foe/EN/Y2013/V6/I4/429

Fig.1 Schematic diagrams of structures A and B. In structure A the three pairs of InGaN/GaN quantum wells are of uniform composition, while in structure B barrier heights are gradually increased toward p-AlGaN layer

Tab.1 Important parameters of AlN, GaN and InN used in the programs

Tab.2 Surface fixed charge densities at interfaces of structure B

Fig.2 (a) Energy band diagram of structure A at forward voltage of 3.4 V. The red dash lines indicate the quasi-Fermi levels; (b) distribution of hole concentration in structure A at 3.4 V forward voltage in log scale

Fig.3 (a) Energy band diagram of structure B at forward voltage of 3.4 V. The red dash lines indicate the quasi-Fermi levels; (b) distribution of hole concentration in structure B at forward voltage of 3.4 V in log scale

Fig.4 Electrostatic field in structure A (black dash line) and structure B (red solid line) near the EBL at forward voltage of 3.4 V

Fig.5 Total light power and IQE as function of current for structure A (black dash line) and structure B (red solid line)

Fig.6 Total spontaneous emission rate for structure A (black dash line) and structure B (red solid line)

1	Oh J H, Oh J R, Park H K, Sung Y G, Do Y R. New paradigm of multi-chip white LEDs: combination of an InGaN blue LED and full down-converted phosphor-converted LEDs. Optics Express , 2011, 19(Suppl 3): A270-A279 doi: 10.1364/OE.19.00A270 pmid:21643368
2	Li J, Lin J Y, Jiang H X. Growth of III-nitride photonic structures on large area silicon substrates. Applied Physics Letters , 2006, 88(17): 171909 doi: 10.1063/1.2199492
3	Liao C T, Tsai M C, Liou B T, Yen S H, Kuo Y K. Improvement in output power of a 460 nm InGaN light-emitting diode using staggered quantum well. Journal of Applied Physics , 2010, 108(6): 063107 doi: 10.1063/1.3471804
4	Gao H Y, Yan F W, ZhangY, Li J M, Zeng Y P, Wang G H. Enhancement of the light output power of InGaN/GaN light-emitting diodes grown on pyramidal patterned sapphire substrates in the micro- and nanoscale. Journal of Applied Physics , 2008, 103(1): 014314 doi: 10.1063/1.2830981
5	Lee J H, Lee D Y, Oh B W, Lee J H. Comparison of InGaN-based LEDs grown on conventional sapphire and cone-shape-patterned sapphire substrate. IEEE Transactions on Electron Devices , 2010, 57(1): 157-163 doi: 10.1109/TED.2009.2034495
6	Tansu N, Mawst L J. Current injection efficiency of InGaAsN quantum-well lasers. Journal of Applied Physics , 2005, 97(5): 054502 doi: 10.1063/1.1852697
7	Choi S, Ji M H, Kim J, Kim H J, Satter M M, Yoder P D, Ryou J H, Dupuis R D, Fischer A M, Ponce F A. Efficiency droop due to electron spill-over and limited hole injection in III-nitride visible light-emitting diodes employing lattice-matched InAlN electron blocking layers. Applied Physics Letters , 2012, 101(16): 161110 doi: 10.1063/1.4759044
8	Hori A, Yasunaga D, Satake A, Fujiwara K. Temperature and injection current dependence of electroluminescence intensity in green and blue InGaN single-quantum-well light-emitting diodes. Journal of Applied Physics , 2003, 93(6): 3152-3157 doi: 10.1063/1.1554475
9	Wang C H, Chang S P, Ku P H, Li J C, Lan Y P, Lin C C, Yang H C, Kuo H C, Lu T C, Wang S C, Chang C Y. Hole transport improvement in InGaN/GaN light-emitting diodes by graded-composition multiple quantum barriers. Applied Physics Letters , 2011, 99(17): 171106 doi: 10.1063/1.3655903
10	Otsuji N, Fujiwara K, Sheu J K. Electroluminescence efficiency of blue InGaN/GaN quantum-well diodes with and without an n-InGaN electron reservoir layer. Journal of Applied Physics , 2006, 100(11): 113105 doi: 10.1063/1.2398690
11	Zhao H P, Liu G Y, Arif R A, Tansu N. Current injection efficiency induced efficiency-droop in InGaN quantum well light-emitting diodes. Solid-State Electronics , 2010, 54(10): 1119-1124 doi: 10.1016/j.sse.2010.05.019
12	Zhao H P, Liu G Y, Zhang J, Arif R A, Tansu R. Analysis of internal quantum efficiency and current injection efficiency in III-nitride light-emitting diodes. Journal of Display Technology , 2013, 9(4): 212-225 doi: 10.1109/JDT.2013.2250252
13	Titkov I E, Sannikov D A, Park Y M, Son J K. Blue light emitting diode internal and injection efficiency. AIP Advances , 2012, 2(3): 032117 doi: 10.1063/1.4739409
14	Xu L F, Patel D, Menoni C S, Yeh J Y, Mawst L J, Tansu N. Experimental evidence of the impact of nitrogen on carrier capture and escape times in InGaAsN/GaAs single quantum well. IEEE Photonics Journal , 2012, 4(6): 2262-2271 doi: 10.1109/JPHOT.2012.2230251
15	Tansu N, Mawst L J. The role of hole leakage in 1300-nm InGaAsN quantum-well lasers. Applied Physics Letters , 2003, 82(10): 1500-1502 doi: 10.1063/1.1558218
16	Chang J Y, Tsai M C, Kuo Y K. Advantages of blue InGaN light-emitting diodes with AlGaN barriers. Optics Letters , 2010, 35(9): 1368-1370 doi: 10.1364/OL.35.001368 pmid:20436572
17	Liu G Y, Zhang J, Tan C K, Tansu N. Efficiency-droop suppression by using large-bandgap AlGaInN thin barrier layers in InGaN quantum-well light-emitting diodes. IEEE Photonics Journal , 2013, 5(2): 2201011 doi: 10.1109/JPHOT.2013.2255028
18	Delaney K T, Rinke P, Van de Walle C G. Auger recombination rates in nitrides from first principles. Applied Physics Letters , 2009, 94(19): 191109 doi: 10.1063/1.3133359
19	Tan C K, Zhang J, Li X H, Liu G Y, Tayo B O, Tansu N. First-principle electronic properties of dilute-As GaNAs alloy for visible light emitters. Journal of Display Technology , 2013, 9(4): 272-279 doi: 10.1109/JDT.2013.2248342
20	Kuo Y K, Chang J Y, Tsai M C. Enhancement in hole-injection efficiency of blue InGaN light-emitting diodes from reduced polarization by some specific designs for the electron blocking layer. Optics Letters , 2010, 35(19): 3285-3287 doi: 10.1364/OL.35.003285 pmid:20890361
21	Kuo Y K, Tsai M C, Yen S H. Numerical simulation of blue InGaN light-emitting diodes with polarization-matched AlGaInN electron-blocking layer and barrier layer. Optics Communications , 2009, 282(21): 4252-4255 doi: 10.1016/j.optcom.2009.07.036
22	Zhang Y Y, Yin Y A. Performance enhancement of blue light-emitting diodes with a special designed AlGaN/GaN superlattice electron-blocking layer. Applied Physics Letters , 2011, 99(22): 221103 doi: 10.1063/1.3653390
23	Vampola K J, Iza M, Keller S, DenBaars S P, Nakamura S. Measurement of electron overflow in 450 nm InGaN light-emitting diode structures. Applied Physics Letters , 2009, 94(6): 061116-1- 061116-3 doi: 10.1063/1.3081059
24	Liou B T, Tsai M C, Liao C T, Yen S H, Kuo Y K. Numerical investigation of blue InGaN light-emitting diodes with staggered quantum wells. Proceedings of the Society for Photo-Instrumentation Engineers , 2009, 7211: 72111D-1-72111D-8 doi: 10.1117/12.808880
25	Jain S C, Willander M, Narayan J, Overstraeten R V. III-nitrides: growth, characterization, and properties. Journal of Applied Physics , 2000, 87(3): 965-1006 doi: 10.1063/1.371971
26	Yen S H, Kuo Y K. Polarization-dependent optical characteristics of violet InGaN laser diodes. Journal of Applied Physics , 2008, 103(10): 103115-1-103115-6 doi: 10.1063/1.2937247
27	Kuo Y K, Yen S H, Wang Y W. Simulation of deep ultraviolet light-emitting diodes. Proceedings of the Society for Photo-Instrumentation Engineers, 2007, 6669: 66691J
28	Ambacher O, Foutz B, Smart J, Shealy J R, Weimann N G, Chu K, Murphy M, Sierakowski A J, Schaff W J, Eastman L F, Dimitrov R, Mitchell A, Stutzmann M. Two dimensional electron gases induced by spontaneous and piezoelectric polarization in undoped and doped AlGaN/GaN hetero-structures. Journal of Applied Physics , 2000, 87(1): 334-344 doi: 10.1063/1.371866
29	Fiorentini V, Bernardini F, Ambacher O. Evidence for nonlinear macroscopic polarization in III-V nitride alloy heterostructures. Applied Physics Letters , 2002, 80(7): 1204-1206 doi: 10.1063/1.1448668
30	Ridley B K, Schaff W J, Eastman L F. Theoretical model for polarization superlattices: Energy levels and intersubband transitions. Journal of Applied Physics , 2003, 94(6): 3972-3978 doi: 10.1063/1.1601686
31	Vurgaftman I, Meyer J R. Band parameters for nitrogen-containing semiconductors. Journal of Applied Physics , 2003, 94(6): 3675-3696 doi: 10.1063/1.1600519
32	Vurgaftman I, Meyer J R, Ram-Mohan L R. Band parameters for III-V compound semiconductors and their alloys. Journal of Applied Physics , 2001, 89(11): 5815-5875 doi: 10.1063/1.1368156
33	Chichibu S F, Abare A C, Minsky M S, Keller S, Fleischer S B, Bowers J E, Hu E, Mishra U K, Coldren L A, DenBaars S P, Sota T. Effective band gap inhomogeneity and piezoelectric field in InGaN/GaN multiquantum well structures. Applied Physics Letters , 1998, 73(14): 2006-2008 doi: 10.1063/1.122350
34	Feezell D F, Speck J S, DenBaars S P, Nakamura S. Semipolar (20-2-1) InGaN/GaN light-emitting diodes for high-efficiency solid-state lighting. Journal of Display Technology , 2013, 9(4): 190-198 doi: 10.1109/JDT.2012.2227682
35	Farrell R M, Haeger D A, Fujito K, DenBaars S P, Nakamura S, Speck J S. Morphological evolution of InGaN/GaN light-emitting diodes grown on free-standing m-plane GaN substrates. Journal of Applied Physics , 2013, 113(6): 063504 doi: 10.1063/1.4790636
36	Zhang J, Tansu N. Optical gain and laser characteristics of InGaN quantum wells on ternary InGaN substrates. IEEE Photonics Journal , 2013, 5(2): 2600111 doi: 10.1109/JPHOT.2013.2247587
37	Zhao H P, Liu G Y, Zhang J, Poplawsky J D, Dierolf V, Tansu N. Approaches for high internal quantum efficiency green InGaN light-emitting diodes with large overlap quantum wells. Optics Express , 2011, 19(Suppl 4): A991-A1007 doi: 10.1364/OE.19.00A991 pmid:21747571

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