Nanopatterning and Devices
We use photo-lithography and e-beam lithography based methods to pattern materials on the nano and micro scale. This top-down approach is used to cut graphene and other 2D crystals into precise nanostructures essential for their application in electronics and opto-electronics.
The active materials in the devices are typically 2D crystals. The nanoelectronic devices are fabricated on a wide variety of substrates including doped Si wafers , quartz, flexible plastics, and specialized Si-based TEM grids for in-situ electron microscopy.
All 2D Electronics and Opto-Electronics (Graphene:TMD:BN stacks)
Lateral geometry devices utilizing monolayer graphene electrodes and 2D WS2 semiconductor. Both materials are grown on 2cm scale using CVD methods and transferred to Si wafers for back gate control. Research involves controlling the graphene:WS2 interface for reduce barriers and understanding the interlayer charge transfer and coupling.
The image below shows the e-beam lithography fabrication procedures and the resulting 2D based devices used as a photodetector.
We use both custom built probe stations for room temperature characterization and vacuum chambers for moisture free analysis. Cryogenic measurements are carrier out to elucidate the thermal activated processes in transport.