Vertical Pillar-Superlattice Array and Graphene Hybrid Light Emitting Diodes

Abstract

We report a type of device that combines vertical arrays of one-dimensional (1D) pillar-superlattice (PSL) structures with 2D graphene sheets to yield a class of light emitting diode (LED) with interesting mechanical, optical, and electrical characteristics. In this application, graphene sheets coated with very thin metal layers exhibit good mechanical and electrical properties and an ability to mount, in a freely suspended configuration, on the PSL arrays as a top window electrode. Optical characterization demonstrates that graphene exhibits excellent optical transparency even after deposition of the thin metal films. Thermal annealing of the graphene/metal (Gr/M) contact to the GaAs decreases the contact resistance, to provide enhanced carrier injection. The resulting PSL-Gr/M LEDs exhibit bright light emission over large areas. The result suggests the utility of graphene-based materials as electrodes in devices with unusual, nonplanar 3D architectures.

Improved heat dissipation in gallium nitride light-emitting diodes with embedded graphene oxide pattern

“…Graphene has attracted a tremendous amount of attention over the past few years because of its two dimensionality and unique physical properties 14,15 , which advance the graphene a promising next-generation material of widespread technological applications such as high-speed transistors 16 , flexible transparent heaters 17 , electrical interconnects 18 and transparent conducting electrodes in optoelectronic devices [19][20][21][22] . Despite graphene's many other remarkable properties, the high intrinsic thermal conductivity, largely contributed by phonon component as a result of strong bonding of the light carbon atoms, has been focused to be a key advantage for applications in microelectronics and optoelectronic and photonic devices to alleviate the heat dissipation problems [23][24][25] .…”

Plasmon-polaritons on graphene-metal surface and their use in biosensors

“…3,5,7 Although the main research focus is concentrated on the conventional electronics, many unusual applications of graphene emerge. Graphene based macroelectronics, 8 photonics, 9,10 and optoelectronics 11,12 are promising research areas where unusual properties of graphene can provide new perspectives.…”

Graphene-contact electrically driven microdisk lasers

“…The graphene sheet is well-attached to the surface of the microdisk and suspended freely in air between the microdisk and the outside dielectric material, which is not usually feasible in conventional metal electrodes. Owing to the excellent flexibility and mechanical strength of graphene 8,9 , the graphene electrode can be mounted conformally on the complex surface of the non-planar threedimensional (3D) nanostructure, which has a large height variation of 550 nm from the dielectric ring to the microdisk ( Supplementary Fig. S1h).…”