Transfer-Free Graphene for High-Quality Wafer-Scale Free-Standing GaN Membrane by Remote Epitaxy

To fabricate universal platforms for electronic and photonic devices with significantly reduced material costs, it is highly essential to realize free-standing membranes with successful separation of active materials from substrates. However, conventional techniques have their own drawbacks considering poor interface quality, difficulty in stack-up, or materials limitations. Recently, remote epitaxy has posed a remarkable potential that can ultimately overcome the existing challenges and produce high crystalline quality even with the simplicity in choosing the materials. 2D material (e.g. graphene) enables remote interaction between two materials and results in the “remote” epitaxial growth of the material (III-N, III-V, or complex oxides). In this study, we demonstrated an ultra-stable and transfer-free 2D platform using pseudo-graphene(pGr)/SiC in remote epitaxy of GaN. Our approach removed the process for fabricating conventional pGr by exfoliation and achieved wafer-scale high-quality free-standing GaN membrane. This can pave the way for realizing multiple wafer-scale GaN free-standing membranes with high-quality using a single SiC.