Elucidating the Physical Property of the InGaN Nanorod Light-Emitting Diode: Large Tunneling Effect

The current-voltage (I- V) characteristics of the InGaN nanorod light-emitting diode (LED) are evaluated using nanoprobes installed on a field-emission scanning electron microscope. The saturated current of the InGaN nanorod LED (IO = 2 × 10^-9A) is found to be orders of magnitude higher than those obtained by downscaling a conventional InGaN LED to a chip size of 300 × 300 μm² (IO1 = 1 × 10^-25 A; IO2 = 1 × 10^-14 A). This observation is explained by the fact that the nanorod LED is associated with enhanced tunneling of injected carriers and, therefore, reduction of the defect-assisted leakage current and the diffusion-recombination process that normally occurs in InGaN LEDs.