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.

The mechanical properties of benzocyclobutene film are investigated at the nanoscale by nano-indentation using atomic force microscopy (AFM). The force versus indentation depth data were collected with two different AFM tips of radii ϳ20 and ϳ380 nm. A strong size effect of the plastic flow stress was observed as the radius of the indenter tip was reduced. More important, the material exhibited pronounced strain rate sensitivity when probed at the nanoscale, while it was rate insensitive at larger scales. These two size effects were quantified by analytic and finite element modeling.

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