Citation: |
Dongxue Wu, Ping Ma, Boting Liu, Shuo Zhang, Junxi Wang, Jinmin Li. Increased effective reflection and transmission at the GaN-sapphire interface of LEDs grown on patterned sapphire substrates[J]. Journal of Semiconductors, 2016, 37(10): 104003. doi: 10.1088/1674-4926/37/10/104003
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D X Wu, P Ma, B T Liu, S Zhang, J X Wang, J M Li. Increased effective reflection and transmission at the GaN-sapphire interface of LEDs grown on patterned sapphire substrates[J]. J. Semicond., 2016, 37(10): 104003. doi: 10.1088/1674-4926/37/10/104003.
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Increased effective reflection and transmission at the GaN-sapphire interface of LEDs grown on patterned sapphire substrates
DOI: 10.1088/1674-4926/37/10/104003
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Abstract
The effect of patterned sapphire substrate (PSS) on the top-surface (P-GaN-surface) and the bottom-surface (sapphire-surface) of the light output power (LOP) of GaN-based LEDs was investigated, in order to study the changes in reflection and transmission of the GaN-sapphire interface. Experimental research and computer simulations were combined to reveal a great enhancement in LOP from either the top or bottom surface of GaN-based LEDs, which are prepared on patterned sapphire substrates (PSS-LEDs). Furthermore, the results were compared to those of the conventional LEDs prepared on the planar sapphire substrates (CSS-LEDs). A detailed theoretical analysis was also presented to further support the explanation for the increase in both the effective reflection and transmission of PSS-GaN interface layers and to explain the causes of increased LOP values. Moreover, the bottom-surface of the PSS-LED chip shows slightly increased light output performance when compared to that of the top-surface. Therefore, the light extraction efficiency (LEE) can be further enhanced by integrating the method of PSS and flip-chip structure design. -
References
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