3D Nanorobotic Manipulations of Multi-Walled Carbon Nanotubes

Multi-walled carbon nanotubes (MWNTs) are manipulated in 3D space with a 10-DOF nanorobotic manipulator, which is actuated with PZTs and Picomotors (New Focus Inc.) and operated inside a scanning electronic microscope (SEM). The coarse linear resolutions of the manipulator are better than 30nm (X, Y, Z stages actuated by Picomotors) and the rotary one 2mrad, while the resolutions of fine motions (actuated by PZTs) are within nano-order. AFM cantilevers are used as the end-effector. Several kinds of manipulations of MWNTs are performed with the developed manipulators in the assistance of dielectrophoresis and van der Waals forces. A single MWNT with estimated dimensions of φ40nm×7μm has been picked up on an AFM cantilever. Another φ50nm×6μm MWNT is placed between two cantilevers, and still another φ40nm×8μm MWNT is bent between a cantilever and sample substrate. Carbon nanotube (CNT) junctions are basic building blocks for more complex devices based on CNTs. A cross-junction was constructed with two MWNTs of dimensions of ~φ40nm×6μm and ~φ50nm×7μm, and a T-junction was made of two MWNTs with the dimensions of ~φ40nm×3μm and ~φ50nm×2μm. Force measurements are performed and the flexural rigidity and Young’s Modulus of an ~φ30nm×7μm MWNT are estimated to be 8.641×10Nm and 2.17TPa respectively. Such manipulations are essential for both the property research of CNTs and the fabrication of CNT-based NEMS.