Jia Research Institute claims to find the main cause of decline in nitride-based LED light efficiency

OFweek Semiconductor Lighting Network: According to reports, the University of California, Santa Barbara Institute said they found the root cause of the inefficiency of LED lighting technology for general lighting. Their findings help engineers develop a new generation of high-performance, high-performance lighting solutions that replace existing incandescent and fluorescent lights.

Professor Van de Walle and his colleagues are improving the performance of high-performance, non-toxic and long-life nitride-based LEDs . They delved into the phenomenon of LED light decay under long-term high-power driving. The cause of this phenomenon has caused a lot of controversy, but researchers at the University of California, Santa Barbara, said they used quantum mechanical calculations to find the mechanism for the formation of this phenomenon.

They concluded that LED droop is caused by Auger recombination. Auger recombination is a phenomenon that occurs in a semiconductor where three charged particles react with each other but do not emit photons. The researchers also found that the indirect Auger effect involving the scattering mechanism is very significant. This finding is explained by the fact that in the previous theoretical studies, the direct Auger process was used to predict the inconsistency between LED light decay and actual measurement results.

In nitride-based LEDs, these indirect processes form the main Auger recombination. Emmanouil Kioupakis, a postdoctoral researcher at the University of California, Santa Barbara, said the first author of the article published in the April 19th issue of Applied Physics. The other authors of this article are Van de Walle, Patrick Rinke, who works at the Fritz Haber Institute in Germany, and Kris Delaney is a scientist at the University of California, Santa Barbara.

Researchers believe that because the Auger effect is an internal mechanism, LED light decay cannot be eliminated, but it can be minimized. Carrier density can be reduced by using a wider quantum well and growing the device in a non-polarized or semi-polarized direction.

Leading the research, Professor Van de Walle of the Department of Materials at the University of California, Santa Barbara, said, "Discovering problems is a prerequisite for resolution. After finding out that Auger recombination is the main cause, we can focus on inhibiting or avoiding this. An innovative approach to the mechanism."

The research was funded by the Center for Energy Efficient Materials. The Energy Efficient Materials Research Center is co-financed by the US Department of Energy and the University of California, Santa Barbara Semiconductor Lighting and Energy Center. The calculations were provided by the US Department of Energy's National Energy Research Scientific Computing Center at the University of California at Berkeley, at the California Nanosystems Research Center at the University of California, Santa Barbara, and the National Science Foundation project TeraGrid.

Article source: China Light Network