Investigation of Electrical Properties of InGaN‐Based Micro‐Light‐Emitting Diode Arrays Achieved by Direct Epitaxy

A systematic study has been conducted on a series of InGaN‐based micro‐light‐emitting diode (μLED) array samples which are achieved using the direct epitaxy overgrown approach on patterned templates by metalorganic chemical vapor deposition technique, where the diameters of the μLEDs are 40, 5, and 3.6 μm, respectively. The selective epitaxy approach allows to circumvent the major limitations of conventional fabrication methods of μLEDs which unavoidably introduce dry‐etching‐induced damages. Electrical characterizations are performed on the selective epitaxy overgrown μLEDs as well as conventional μLEDs fabricated using a standard dry‐etching method. For the overgrown μLEDs, the leakage current per μLED is smaller than those of the conventionally mesa‐etched μLEDs. It is worth highlighting that the single 3.6 μm μLED exhibits as low as a leakage current of 14.1 nA at a bias of −5 V. Moreover, in terms of leakage current density, the overgrown μLEDs exhibit much smaller and more consistent leakage than their mesa‐etched counterparts. Operational voltage RC constants also show more favorable to the overgrown devices than the conventionally mesa‐etched μLEDs.