Enhancing optoelectronic and communication performance of green μ-LEDs using pre-strain layer structures

An efficient pre-strained layer structure is proposed, which combines a pre-layer with a pre-well, to prepare a 2 × 3 InGaN green micro-light-emitting-diode (μ-LED) device array with a diameter of 20 μm. The addition of the pre-layer increases the lateral lattice constant of the bottom layer of the structure. This alleviates the strain accumulation of lattice mismatch, reduces the quantum-confined Stark effect (QCSE) of the green μ-LEDs, improves the crystal quality, and produces better optoelectronic properties. Under stress modulation, the external quantum efficiency and -3 dB modulation of the green μ-LED array reach 16.6% and 411 MHz, respectively, which are 14.8 and 91.2% higher than those of the traditional structure.