Nanoindentation of polycarbonate using carbon nanotube tip

We have demonstrated nanoindentation by a nanotube tip on a polycarbonate surface. The indentation was performed with a force curve measurement using a tapping-mode atomic force microscope in air at room temperature. A nanotube with high buckling force larger than 1 muN is required for the formation of the indent on the polycarbonate. The indent widths are comparable to the nanotube diameter and their spacing is similar to 50 nm. Although excess force during the indentation induces plastic deformation of the nanotube cap, the body of the nanotube retains its original shape because of the high axial strength of the nanotube. The ability to fabricate a nanometer-scale dot array in air without any chemical reactions demonstrates potential for use in information storage with high density.