Exfoliated single-crystalline GaN films grown on graphene lead to new types of LEDs

Researchers at the IBM T. J. Watson Research Center (Yorktown Heights, NY) have figured out how to use graphene as a template to repeatedly grow and exfoliate entire single-crystalline gallium nitride (GaN) films; the process extends to the creation of GaN-based multi-quantum-well structures that can be (and have been) used to make fully functional LEDs.¹

Reusable graphene template
The graphene, which is epitaxially grown on a silicon carbide substrate, serves as a reusable template for growing III-nitride films. The resulting GaN-based multi-quantum-well structures are quite flexible -- flexible enough, in fact, that the blue-emitting LEDs that researchers fabricated were actually flexible LEDs transferred to plastic tape.

Such exfoliated film heterostructures can be transfered to other types of substrates as well, including silicon; as a result, the technique could become part of the device design and fabrication process for advanced silicon photonics devices.

REFERENCE:

1. Jeehwan Kim et al., Nature Communications (2014); doi: 10.1038/ncomms5836