Uniform Growth of High-Quality Oxide Thin Films on Graphene Using a CdSe Quantum Dot Array Seeding Layer

Graphene displays outstanding properties as an electrode and a semiconducting channel material for transistors; however, the weak interfacial bond between graphene and an inorganic oxide material-based insulator presents a major constraint on these applications. Here, we report a new approach to improving the interface between the two materials using a CdSe quantum dot (QD)-based seeding layer in an inorganic material-graphene junction. CdSe QDs were electrochemically grown on graphene without degrading the properties of the graphene layer. The graphene structure was then used as the electrode in an oxide semiconductor by depositing a zinc oxide thin film onto the graphene coated with a QD seed layer (QD/G). The zinc oxide film adhered strongly to the graphene layer and provided a low contact resistance. A high-k dielectric layer in the form of an HfO2 film, which is an essential element in the fabrication of high-performance graphene-based field effect transistors, was also uniformly formed on the QD/G sheet using atomic layer deposition. The resulting transistors provided a relatively good performance, yielding hole and electron mobilities of 2600 and 2000 cm(2)/V·s.