Crack-free InGaN multiple quantum wells (MQWs) light-emitting diodes with embedded electrode structures (EE-LEDs) were transferred from Si (111) substrate onto the electroplating copper submount. Crystalline quality was investigated by the high resolution x-ray diffraction (HR-XRD) measurement, in which no obvious deteriorations were found in the MQWs structure after the LEDs transferred from silicon substrate onto copper except for a partial residual strain relaxation in the film. The strain relaxation after silicon removal leads to a reduction in quantum confined stark effect (QCSE), which results in the enhancement of internal quantum efficiency (IQE). In comparison to the conventional LEDs on silicon substrate, the light output of the EE-LEDs on copper was enhanced by 122% at an injection current of 350 mA. Besides the enhancement of IQE, the improvement is also attributed to the following factors: the removal of the absorptive substrate, the inserting of the metal reflector between the EE-LEDs structure and the copper submount, the elimination of the electrode-shading, and the rough surface of the exposed AlN buffer layer.

Crack-free GaN/InGaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) are transferred from Si substrate onto electroplating Cu submount with embedded wide p-electrodes. The vertical-conducting n-side-up configuration of the LED is achieved by using the through-hole structure. The widened embedded p-electrode covers almost the whole transparent conductive layer (TCL), which could not be applied in the conventional p-side-up LEDs due to the electrode-shading effect. Therefore, the widened p-electrode improves the current spreading property and the uniformity of luminescence. The working voltage and series resistance are thereby reduced. The light output of embedded wide p-electrode LEDs on Cu is enhanced by 147% at a driving current of 350 mA, in comparison to conventional LEDs on Si.

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