FIG. 4. Electroluminescence spectra of (a) Sample A (with shallow TQW), (b) Sample B
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FIG. 4. Electroluminescence spectra of (a) Sample A (with shallow TQW), (b) Sample B (with shallow RQW), (c) Sample C (w/o. shallow QWs) at Various injection currents. (d) The magnitude of the blue-shift and the FWHM of the EL emission peak 1.8 nm 2.1 nm 5.1 nm
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1.8 nm. 2.1 nm. FIG. 4. Electroluminescence spectra of (a) Sample A (with shallow TQW), (b) Sample B (with shallow RQW), (c) Sample C (w/o. shallow QWs) at Various injection currents. (d) The magnitude of the blue-shift and the FWHM of the EL emission peak in the - PowerPoint PPT Presentation
Transcript of FIG. 4. Electroluminescence spectra of (a) Sample A (with shallow TQW), (b) Sample B
FIG. 4. Electroluminescencespectra of (a) Sample A (withshallow TQW), (b) Sample B(with shallow RQW), (c) Sample C (w/o. shallow QWs) at Various injection currents. (d) The magnitude of the blue-shift and the FWHM of the EL emission peak in the three samples as a function of injection current.
1.8 nm 2.1 nm
5.1 nm
The LED devices with shallow TQW gave a 0.35 V lower
turn-on voltage and an 80% higher lighting efficiency than
those of LEDs without shallow QWs.
The improvements were ascribed to the weakening effect
of the inserted shallow TQW on the polarization field in the
c-plane GaN-LEDs, leading to enhanced lighting efficiency
and reduced efficiency-droop.
Conclusion
(1)E. F. Schubert and J. K. Kim, Science 308, 1274 (2005).
(2)S. Huang, Y. Xian, B. Fan, Z. Zheng, Z. Chen, W. Jia, H. Jiang, and G.Wang, J. Appl. Phys. 110, 064511 (2011).
(3)M.-H. Kim, M. F. Schubert, Q. Dai, J. K. Kim, E. F. Schubert, J. Piprek and Y. Park, Appl. Phys. Lett. 91, 183507 (2007).
(4)S. J. Chang, S. C. Wei, Y. K. Su, and W. C. Lai, J. lectrochem. Soc. 154,H871 (2007).
References
