Fig. 1.
(Color online) The SEM and AFM images of nucleation layers grown on sapphire. (a, c) The 25-nm-thick in-situ NL. (b, d) The 25-nm-thick SNL.
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Zejie Du, Ruifei Duan, Tongbo Wei, Shuo Zhang, Junxi Wang, Xiaoyan Yi, Yiping Zeng, Junxue Ran, Jinmin Li, Boyu Dong. Producing deep UV-LEDs in high-yield MOVPE by improving AlN crystal quality with sputtered AlN nucleation layer[J]. Journal of Semiconductors, 2017, 38(11): 113003. doi: 10.1088/1674-4926/38/11/113003
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Z J Du, R F Duan, T B Wei, S Zhang, J X Wang, X Y Yi, Y P Zeng, J X Ran, J M Li, B Y Dong. Producing deep UV-LEDs in high-yield MOVPE by improving AlN crystal quality with sputtered AlN nucleation layer[J]. J. Semicond., 2017, 38(11): 113003. doi: 10.1088/1674-4926/38/11/113003.
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Producing deep UV-LEDs in high-yield MOVPE by improving AlN crystal quality with sputtered AlN nucleation layer
DOI: 10.1088/1674-4926/38/11/113003
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Abstract
High-quality AlN layers with low-density threading dislocations are indispensable for high-efficiency deep ultraviolet light-emitting diodes (UV-LEDs). In this work, a high-temperature AlN epitaxial layer was grown on sputtered AlN layer (used as nucleation layer, SNL) by a high-yield industrial metalorganic vapor phase epitaxy (MOVPE). The full width half maximum (FWHM) of the rocking curve shows that the AlN epitaxial layer with SNL has good crystal quality. Furthermore, the relationships between the thickness of SNL and the FWHM values of (002) and (102) peaks were also studied. Finally, utilizing an SNL to enhance the quality of the epitaxial layer, deep UV-LEDs at 282 nm were successfully realized on sapphire substrate by the high-yield industrial MOVPE. The light-output power (LOP) of a deep UV-LED reaches 1.65 mW at 20 mA with external quantum efficiency of 1.87%. In addition, the saturation LOP of the deep UV-LED is 4.31 mW at an injection current of 60 mA. Hence, our studies supply a possible process to grow commercial deep UV-LEDs in high throughput industrial MOVPE, which can increase yield, at lower cost. -
References
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