Sains Malaysiana 43(10)(2014): 1557–1564

Simulation on the Roles of the Number of Quantum Well and Doping

in InxGa1-xN Multiple Quantum Wells LEDs

(Simulasi Peranan Bilangan Telaga Kuantum dan Pendopan dalam Multi Telaga Kuantum InxGa1-xN LEDs)

N. ZAINAL*, E. AZIMAH, Z. HASSAN, H. ABU HASSAN & M.R. HASHIM

Nano-optoelectronics Research and Technology, School of Physics, Universiti Sains Malaysia, 11800 Penang, Malaysia

Received: 2 August 201/Accepted: 10 February 2014

ABSTRACT

In this work, the emission efficiency of InxGa1-xN based light emitting diodes (LEDs) had been numerically investigated with the variation of the number of quantum well. From our calculation, we found that non-uniformity of carriers distribution (especially electron) in the wells leads to serious inhomogeneity of radiative recombination distribution that would degrade the efficiency of the LED with more wells. However, the problem was minimized when the selected quantum barriers were doped with a reasonable doping level. Comparison with other reported experimental works were also included. At the end of this work, we proposed several types of preferable LEDs designs with optimum structural parameters.

Keywords: Light emitting diodes; numerical simulation; optical properties; III-V semiconductors

ABSTRAK

Dalam kajian ini, kecekapan pancaran daripada diod pemancar cahaya (LED) berasaskan InxGa1-xN telah dikaji secara berangka dengan variasi bilangan telaga kuantum. Daripada pengiraan kami, didapati bahawa ketidakseragaman taburan pembawa (terutamanya elektron) dalam telaga memberi kesan kepada ketidakseragaman taburan penggabungan semula menyinar yang serius dan mengurangkan kecekapan LED yang mempunyai bilangan telaga yang tinggi. Walau bagaimanapun, kecekapan diod tersebut dapat diperbaiki apabila sawar kuantum tertentu didopkan pada tahap yang berpatutan. Perbandingan dengan kerja-kerja experimen lain yang telah dilaporkan turut disertakan. Di akhir kajian ini, kami mencadangkan beberapa jenis reka bentuk LED yang lebih baik dengan parameter struktur yang optimum.

Kata kunci: Diod pemancar cahaya; semikonduktor III-V; sifat optikal; simulasi berangka

REFERENCES

ATLAS Manual. 2003. 1&2, Silvaco Software Inc.

Chang, J.Y., Kuo, Y.K. & Tsai M.C. 2011. Correlation of barrier material and quantum-well number for InGaN/(In)GaN blue light-emitting diodes. Physica Status Solidi (a) 208: 729-734.

Chang, J.Y. & Kuo, Y.K. 2003. Simulation of blue InGaN quantum well lasers. Journal of Applied Physics 93: 4992- 4998.

Egawa, T., Ishikawa, H., Umeno, M., Akutsu, N. & Matsumoto, K. 2002. InGaN LED on sapphire substrate grown by MOCVD. Technical Report at Research Center for Micro-structure Devices 9: 191.

Han, S.H., Cho, C.Y., Lee, S.J., Park, T.Y., Kim, T.H., Park, S.H., Kang, S.W., Kim, J.W., Kim, Y.C. & Park, S.J. 2010.

Effect of Mg doping in the barrier of InGaN/GaN multiple quantum well on optical power of light emitting diodes. Applied Physisc Letters 96: 051113.

Hung, H., Lam, K.T., Chang, S.J., Chen, C.H., Kuan, H. & Sun, Y.X. 2008. InGaN/GaN multiple-quantum well LEDs with Si-doped barriers. Journal of the Electrochemical Society 155: H455-H458.

Jenkins, D.W. & Dow, J.D. 1998. Electronic structures and doping of InN, InxGa1-xN, and InxAl1-xN. Physical Review B 39: 3317-3329.

Mohammad, N., Salvador, A.A. & Morkoc, H. 1995. Emerging GaN based devices. Proceedings of the IEEE 83: 1306-1355.

Mueller-Mach, R., Mueller, G.O., Krames, M.R., Shchekin, O.B., Schmidt, P.J., Bechtel, H., Chen, C.H. & Steigelmann, O. 2009. All-nitride monochromatic amber-emitting phosphor-converted light-emitting diodes. Physica Status Solidi RRL 3: 215-217.

Ryou, J.H., Limb, J., Lee, W., Liu, J., Lochner, Z., Yoo, D. & Dupuis, R.D. 2008. Effect of silicon doping in the quantum well barriers on the electrical and optical properties of visible green light emitting diodes. IEEE Photonics Technology Letters 20: 1769-1771.

Xia, C.S., Simon, Z.M., Li, Z.Q., Sheng, Y. & Zhang, Z.H. 2012. Optimal number of quantum wells for blue InGaN/GaN light emitting diodes. Applied Physisc Letters 100: 263504.

Yoshida, H., Kuwabara, M., Yamashita, Y., Takagi, Y., Uchiyama, K. & Kan, H. 2009. AlGaN-based laser diodes for the short-wavelength ultraviolet region. New Journal of Physics 11: 125013.

Zhou, J.R. & Ferry, D.K. 1992a. Simulation of ultra small GaAs MESFET using quantum moment equations. IEEE Transactions on Electron Devices 39: 473-478.

Zhou, J.R. & Ferry, D.K. 1992b. Simulation of ultra-small GaAs MESFET using quantum moment equations-II: Velocity overshoot. IEEE Transactions on Electron Devices 39: 1793-1796.

*Corresponding author; email: norzaini@usm.my