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Chemical mapping of indium rich quantum dots in InGaN/GaN quantum wells

  • N Sharma (a1), H K Cho (a2), J Y Lee (a2) and C J Humphreys (a1)

Abstract

Indium clustering in InGaN/GaN multiple quantum wells (MQWs) is believed to be responsible for the high luminescent efficiency of GaN based light emitting diodes. In this paper we show that substantial clustering can be induced by reducing to zero the interruption time between growth of the GaN barrier layer on the InGaN quantum well. Photoluminescence (PL) shows that this has the effect of increasing the luminescence intensity and decreasing the band gap energy (higher indium concentration). The clusters or quantum dots were examined and quantified by energy filtered transmission electron microscopy (EFTEM), which was used to form chemical distribution maps of indium, gallium and nitrogen. In this paper we will show that this technique can accurately calculate the indium concentration and distribution in the quantum wells. The calculations show that InxGa1−xN quantum dots (width = 1.3nm) exhibit an In concentration of up to x = 0.5, which are embedded in a quantum well matrix with x = 0.05.

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1. Nakamura, S, Science 281, 956 (1998).
2. Chichibu, S, Azuhata, T, Sota, T and Nakamura, S Appl. Phys. Lett. 69, 4188 (1996).
3. Ho, I-hsui and Stringfellow, G B, Appl. Phys. Lett. 69(18) 2701 (1996).
4. Singh, R, Doppalapudi, D, Moustakas, T D, Romano, L T, Appl. Phys. Lett. 70, 1089 (1997).
5. Gerthsen, D, Hahn, E, Neubauer, B, Rosenaur, A, Schon, O, Heuken, M and Rizzi, A Phys. Stat. Sol. (a) 177, 145 (2000).
6. Narukawa, Y, Kawakami, Y, Funato, M, Fujita, S, Fujita, S, Nakamura, S, Phys. Lett. 70(8), 981 (1997).
7. Chen, H, Feenstra, R M, Northrup, J E, Zyweitz, T, Neugebauer, J, Phys. Rev. Lett. 85, 1902 (2000).
8. Sharma, N, Thomas, P, Tricker, D and Humphreys, C J, Appl. Phys. Lett. 77, 1274 (2000).
9. Sharma, N, Barnard, J, Cho, H Koun, Lee, J Yong and Humphreys, C J, in the proceedings of the Microscopy of Semiconducting Materials XII, Oxford, U.K., 26-30th March, (2001).

Chemical mapping of indium rich quantum dots in InGaN/GaN quantum wells

  • N Sharma (a1), H K Cho (a2), J Y Lee (a2) and C J Humphreys (a1)

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