High Thermal Dissipation of Ultra High Power Light-Emitting Diodes by Copper Electroplating
The thermal management has become increasingly important when comes to device applications using ultra high power light emitting diodes (UHPLEDs). To thermally manage the devices in a most effective fashion, we report a novel packaging technique in which a copper electroplating process is directly applied over the red, green, and blue LED chips. With the copper-encapsulated layer, the operation current subsequently administered to these LED chips can be increased easily from a conventional 350 mA to more than 1050 mA stable at room temperature. This process can be well adapted to AlInGaP-based red LED when its working current can be driven all the way up to 1650 mA. At 350 mA, the relative luminous intensity of these specially packaged red, green, and blue LEDs (RGB LEDs) clearly demonstrate a corresponding enhancement of 53%, 69%, and 23% when compared to those of conventionally packaged LEDs. Furthermore, as the injection current of these LED chips increases to 850 mA, the respective improvement in relative luminous intensity of these RGB LEDs chips becomes 431 %, 83%, and 18%, when compared to those of the conventional packaged devices.