Wafer-bonding AIGalnP light emitting diodes with pyramidally patterned metal reflector

We demonstrate and introduce here a pyramidally patterned metal reflector into wafer-bonding AlGaInP light emitting diodes （LEDs） to improve the light extraction efficiency by using a photo-assisted chemical etched GaP：Mg layer. The pyramid patterns were fabricated employing a HF and H202 mixed solution in combination with a 532 nm laser on a GaP：Mg surface firstly, and then a gold reflector layer was evaporated onto the patterned GaP：Mg surface. After the whole chip process, the patterned gold reflector structure was confirmed to be efficient for light extraction and a 18.55% enhancement of the electroluminescent flux has been obtained by an integrating sphere, compared to the surface textured LEDs with flat reflectors.