Nitride deep-ultraviolet light-emitting diodes with microlens array
نویسندگان
چکیده
We report on the fabrication of 280-nm AlGaN-based deep-ultraviolet light-emitting diodes sUV LEDsd on sapphire substrates with an integrated microlens array. Microlenses with a diameter of 12 mm were fabricated on the sapphire substrate by resist thermal reflow and plasma dry etching. LED devices were flip-chip bonded on high thermal conductive AlN ceramic submounts to improve the thermal dissipation, and the emitted UV light was extracted through the sapphire substrates. With the integrated microlens array, a 55% enhancement in the output power at 20-mA dc driving was achieved compared with the same LED without microlens. The light extraction enhancement is the result of the reduced internal reflections of the light caused by the microlens surface profile. © 2005 American Institute of Physics. fDOI: 10.1063/1.1914960g
منابع مشابه
Recent progress and future prospects of AlGaN-based high-efficiency deep-ultraviolet light-emitting diodes
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