Abstract
High quality In0.13Ga0.87N/GaN multiple quantum wells (MQWs) on (0001) sapphire substrate were fabricated by MOCVD method. The quantum well thickness is as thin as 10 Å, and the barrier thickness is 50 Å. We have investigated these ultrathin MQWs by continuous wave (cw) and time-resolved spectroscopy in the picosecond time scales in a wide temperature range from 10 to 290 K. In the luminescence spectrum at 10 K, we observed a broad peak at 3.134 eV which was attributed to the quantum wells emission of InGaN. The full width at half maximum of this peak was 129 meV at 10 K and the broadening at low temperatures which was mostly inhomogeneous was thought to be due to compositional fluctuations and interfacial disorder in the alloy. We also observed an intense and narrow peak at 3.471 eV due to the GaN barrier. The temperature dependence of the luminescence was studied and the peak positions and the intensities of the different peaks were obtained. The activation energy of the InGaN quantum well emission peak was estimated as 69 meV. From the measurements of luminescence intensities and lifetimes at various temperatures, radiative and non-radiative recombination lifetimes were deduced. The results were explained by considering only the localization of the excitons due to potential fluctuations.
| Original language | English |
|---|---|
| Pages (from-to) | 4401-4404 |
| Number of pages | 4 |
| Journal | Thin Solid Films |
| Volume | 515 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 2007 Mar 26 |
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All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry
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Luminescence and ultrafast phenomena in InGaN multiple quantum wells. / Viswanath, Annamraju Kasi; Lee, J. I.; Kim, S. T.; Yang, G. M.; Lee, H. J.; Kim, Dongho.
In: Thin Solid Films, Vol. 515, No. 10, 26.03.2007, p. 4401-4404.Research output: Contribution to journal › Article
TY - JOUR
T1 - Luminescence and ultrafast phenomena in InGaN multiple quantum wells
AU - Viswanath, Annamraju Kasi
AU - Lee, J. I.
AU - Kim, S. T.
AU - Yang, G. M.
AU - Lee, H. J.
AU - Kim, Dongho
PY - 2007/3/26
Y1 - 2007/3/26
N2 - High quality In0.13Ga0.87N/GaN multiple quantum wells (MQWs) on (0001) sapphire substrate were fabricated by MOCVD method. The quantum well thickness is as thin as 10 Å, and the barrier thickness is 50 Å. We have investigated these ultrathin MQWs by continuous wave (cw) and time-resolved spectroscopy in the picosecond time scales in a wide temperature range from 10 to 290 K. In the luminescence spectrum at 10 K, we observed a broad peak at 3.134 eV which was attributed to the quantum wells emission of InGaN. The full width at half maximum of this peak was 129 meV at 10 K and the broadening at low temperatures which was mostly inhomogeneous was thought to be due to compositional fluctuations and interfacial disorder in the alloy. We also observed an intense and narrow peak at 3.471 eV due to the GaN barrier. The temperature dependence of the luminescence was studied and the peak positions and the intensities of the different peaks were obtained. The activation energy of the InGaN quantum well emission peak was estimated as 69 meV. From the measurements of luminescence intensities and lifetimes at various temperatures, radiative and non-radiative recombination lifetimes were deduced. The results were explained by considering only the localization of the excitons due to potential fluctuations.
AB - High quality In0.13Ga0.87N/GaN multiple quantum wells (MQWs) on (0001) sapphire substrate were fabricated by MOCVD method. The quantum well thickness is as thin as 10 Å, and the barrier thickness is 50 Å. We have investigated these ultrathin MQWs by continuous wave (cw) and time-resolved spectroscopy in the picosecond time scales in a wide temperature range from 10 to 290 K. In the luminescence spectrum at 10 K, we observed a broad peak at 3.134 eV which was attributed to the quantum wells emission of InGaN. The full width at half maximum of this peak was 129 meV at 10 K and the broadening at low temperatures which was mostly inhomogeneous was thought to be due to compositional fluctuations and interfacial disorder in the alloy. We also observed an intense and narrow peak at 3.471 eV due to the GaN barrier. The temperature dependence of the luminescence was studied and the peak positions and the intensities of the different peaks were obtained. The activation energy of the InGaN quantum well emission peak was estimated as 69 meV. From the measurements of luminescence intensities and lifetimes at various temperatures, radiative and non-radiative recombination lifetimes were deduced. The results were explained by considering only the localization of the excitons due to potential fluctuations.
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U2 - 10.1016/j.tsf.2006.07.110
DO - 10.1016/j.tsf.2006.07.110
M3 - Article
AN - SCOPUS:33847049916
VL - 515
SP - 4401
EP - 4404
JO - Thin Solid Films
JF - Thin Solid Films
SN - 0040-6090
IS - 10
ER -