Epitaxial growth using graphene (GR), weakly bonded by van der Waals force, is a subject of interest for fabricating technologically important semiconductor membranes. Such membranes can potentially offer effective cooling and dimensional scale-down for high voltage power devices and deep ultraviolet optoelectronics at a fraction of the bulk-device cost. Here, we report on a large-area β-Ga2O3 nanomembrane spontaneous-exfoliation (1 cm × 1 cm) from layers of compressive-strained epitaxial graphene (EG) grown on SiC, and demonstrated high-responsivity flexible solar-blind photodetectors. The EG was favorably influenced by lattice arrangement of SiC, and thus enabled β-Ga2O3 direct-epitaxy on the EG. The β-Ga2O3 layer was spontaneously exfoliated at the interface of GR owing to its low interfacial toughness by controlling the energy release rate through electroplated Ni layers. The use of GR templates contributes to the seamless exfoliation of the nanomembranes, and the technique is relevant to eventual nanomembrane-based integrated device technology.
KAUST Repository Item: Exported on 2021-03-30
Acknowledged KAUST grant number(s): BAS/1/1614-01-01, KACST TIC R2-FP-008
Acknowledgements: The work was support by King Abdullah University of Science and Technology (KAUST) baseline funding BAS/1/1614-01-01. We acknowledge access to the KAUST Imaging and Characterization Core Lab for optical and electron microscopy measurements, and access to the Nanofabrication Core Lab for fabrication process of Ni stressor and devices. This work was also supported by Ceramic Strategic Research Program (KPP200001) through Korea Institute of Ceramic Engineering and Technology (KICET). J.-W.M., T.K.N., and B.S.O. gratefully acknowledge the funding support from King Abdulaziz City for Science and Technology (grant no. KACST TIC R2-FP-008).