Determining Mechanical Properties of Carbon Microcoils Using Lateral Force Microscopy

Mechanical properties of amorphous carbon microcoil (CMC) synthesized by thermal chemical vapor deposition method were examined in compression and tension tests, using the lateral force mode of atomic force microscope (AFM). The AFM cantilever tip was manipulated by a piezoelectric scanner to contact, pull, and push an individual CMC. The lateral force that was exerted by the CMC deformation causes the twist of the AFM cantilever. It was monitored by the laser and photodetector of the AFM during the experiments. A linear response of the CMC was observed in the range of 25 nm to 5 mum of tension experiments. The results show that the spring constant of the CMC is reasonably proportional to the coil number. The shear modulus of the amorphous CMC is estimated to be 3 plusmn 0.2 GPa. The proposed method is promising to manipulate the compression and tension of the CMC and to measure the lateral force exerted in an ambient environment.