We demonstrated a nanoscale electromechanical actuator operation using an isolated nanoscale spring. The four-turn Si nanosprings were grown using the oblique angle deposition technique with substrate rotation, and were rendered conductive by coating with a 10-nm-thick Co layer using chemical vapor deposition. The electromechanical actuation of a nanospring was performed by passing through a dc current using a conductive atomic force microscope ͑AFM͒ tip. The electromagnetic force leads to spring compression, which is measured with the same AFM tip. The spring constant was determined from these measurements and was consistent with that obtained from a finite element analysis.

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Due to the shadowing effect, the oblique angle deposition technique can produce nanorods tilted toward the incident deposition flux. Periodic posts serving as seeds on a substrate allow the fabrication of nanorod arrays with controllable separations. However, in a conventional oblique angle deposition with no substrate rotation, nanorods grow faster along their widths in the direction perpendicular to the plane of incident flux. This anisotropic growth can result in 'fan-out' shapes of nanorods that touch each other due to the faster growing widths. Asymmetric two-phase substrate rotation was designed to eliminate the side growth in oblique angle deposition. In this method, the growing rods are exposed to the deposition flux from all angles with some portion of a rod surface receiving more flux than the rest. We fabricated well-aligned Si nanorod arrays with uniform sizes from templates arranged in square and triangular lattices using this two-phase substrate rotation method.

Amorphous silicon nanocolumns, square nanospirals, and multilayer spiral/column rods are fabricated on bare Si substrates and monolayer colloid substrates by glancing angle deposition. The grown films are studied by scanning electron microscopy and transmission electron microscopy. The size of the deposited Si columns and spirals increases with the size of colloid particles for fixed incident angle of deposition flux. The feasibility of fabricating separated, well-ordered square spirals provides a cost effective and simple way to fabricate photonic crystals.

The hydrophilicity of vertically aligned metal nanorods with sharp nanotips were investigated experimentally. Ruthenium and platinum nanorod arrays were deposited on flat silicon substrates using oblique angle sputter deposition. We show that the effects of nanotips on nanorods should be considered in the "hemiwicking" model for hydrophilic metallic samples. With the influence of nanotips, we successfully explained the experimental contact angles of water sessile drops on metallic nanorod surfaces. Our experiments confirm that the shape of the nanorods is an important parameter in determining the hydrophilicity of the nanostructured surfaces.