Yang Heng

Doubly Clamped Nanobeam as a Piezoresistive Mass Sensor

In this paper, we present a novel technology to realize a doubly clamped nanobeam, which is preferred to cantilever because of its higher natural frequency with a same dimension, as a piezoresistive mass sensor. Ar selective bombardment was applied on a 200 nm thick doubly clamped nanobeam to form a piezoresistor in a Wheaston bridge along with other ordinary resistors. The device was electrostatically actuated and readout piezoresistively. The achieved merit product of Q-factor and f0 in air is as high as 3.5 times 108 , which hints a better mass detection resolution compared with its counterpart of micro cantilever, while our approach is simple and easily controlled.

Graphene Domains Synthesized on Electroplated Copper by Chemical Vapor Deposition

Electroplated Cu, which can be compatible with integrated circuit technology and large-scale silicon wafers, is explored as a substrate to synthesize graphene domains by ambient-pressure chemical vapor deposition. Hexagonal single crystal domains of graphene are synthesized on electroplated Cu under dilute methane gas flow. Scanning electron microscopy images of graphene domains grown on electroplated Cu indicate that the domain size is time-dependent, and the domains can cross Cu grain boundaries and are distributed more uniformly on electroplated Cu surface than those grown on Cu foil.