Distinct U-shape efficiency-versus-current curves in AlGaN-based deep-ultraviolet light-emitting diodes.
نویسندگان
چکیده
The efficiency of an AlGaN deep-ultraviolet light-emitting diode with peak emission wavelength of 285 nm is investigated as a function of current over a wide range of temperatures (110 K to 300 K). We find that the efficiency-versus-current curve exhibits unique and distinct features over the entire temperature range including three points of inflection. At low temperatures, the change in slope in the efficiency-versus-current curve is particularly pronounced producing a minimum in the efficiency after which the efficiency rises again. Furthermore, at high current density, the low-temperature efficiency exceeds the room-temperature efficiency. The feature-rich efficiency-versus-current curve is consistent with an enhancement in p-type conductivity by field-ionization of acceptors that occurs in the high-injection regime and is particularly pronounced at low temperatures. Differential conductivity measurements show a marked rise in the high-injection regime that is well correlated to the minimum point in the efficiency-versus-current curve.
منابع مشابه
Recent progress and future prospects of AlGaN-based high-efficiency deep-ultraviolet light-emitting diodes
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عنوان ژورنال:
- Optics express
دوره 23 12 شماره
صفحات -
تاریخ انتشار 2015