Electrically driven on-chip transferrable micro-LEDs

In this study, we report the experimental demonstration of electrically driven on-chip transferrable microdisk light-emitting diodes (LEDs). A vertical p– i– n doped AlGaInP microdisk, including multi-quantum-well structures, is top-down-fabricated, on-chip micro-transferred, and converted into single micro-LEDs. Optically transparent and mechanically flexible multilayered graphene sheets are judiciously designed and introduced to the top and bottom surfaces of a single microdisk, thereby forming the top and bottom contacts. Using electroluminescence measurements, the fabricated micro-LEDs are characterized; they exhibit diode-like transport behaviors, spectroscopic light-out vs current ( L– I) characteristics, and polarization-resolved emission properties. We believe that the proposed all-graphene-contact approach offers a direct and easy current injection scheme and further helps electrify various on-chip transferrable microarchitectures.