Graphene-Quantum-Dot-Mediated Semiconductor Bonding: A Route to Optoelectronic Double Heterostructures and Wavelength-Converting Interfaces

A semiconductor bonding technique that is mediated by graphene quantum dots is proposed and demonstrated. The mechanical stability, electrical conductivity, and optical activity in the bonded interfaces are experimentally verified. First, the bonding scheme can be used for the formation of double heterostructures with a core material of graphene quantum dots. The Si/graphene quantum dots/Si double heterostructures fabricated in this study can constitute a new basis for next-generation nanophotonic devices with high photon and carrier confinements, earth abundance, environmental friendliness, and excellent optical and electrical controllability via silicon clads. Second, the bonding mediated by the graphene quantum dots can be used as an optical-wavelength-converting semiconductor interface, as experimentally demonstrated in this study. The proposed fabrication method simultaneously realizes bond formation and interfacial function generation and, thereby, can lead to efficient device production. Our bonding scheme might improve the performance of optoelectronic devices, for example, by allowing spectral light incidence suitable for each photovoltaic material in multijunction solar cells and by delivering preferred frequencies to the optical transceiver components in photonic integrated circuits.