Carbon nanotubes have been grown with a sharply defined zigzag structure by introducing changes in the direction of applied electric field during dc plasma enhanced chemical vapor deposition (PECVD). The nanotubes maintain the same diameter before and after each bend while preserving the catalyst particle at the tip of growing nanotubes. The bends have very sharp radii of curvature of only ∼25 nm. As a simple inclined field direction cannot produce such a zigzag growth due to the tendency of field lines intersecting perpendicular to the local surface, the bending has been introduced primarily by dramatically manipulating the electric field lines through controlled movement of field-concentrating conductor plates.

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Carbon nanotube morphology has been engineered via simple control of applied voltage during dc plasma chemical vapor deposition growth. Below a critical applied voltage, a nanotube configuration of vertically aligned tubes with a constant diameter is obtained. Above the critical voltage, a nanocone-type configuration is obtained. The strongly field-dependent transition in morphology is attributed primarily to the plasma etching and decrease in the size of nanotube-nucleating catalyst particles. A two-step control of applied voltage allows a creation of dual-structured nanotube morphology consisting of a broad base nanocone (ϳ200 nm dia.) with a small diameter nanotube ͑ϳ7 nm͒ vertically emanating from the apex of the nanocone, which may be useful for atomic force microscopy.

Patterned recording media consisting of a vertically aligned array of L10 phase CoPt nanowires embedded in a thin anodized aluminum oxide (AAO) template on silicon has been prepared. A sputter deposited thin film of aluminum on silicon was anodized and a CoPt magnetic alloy was electrodeposited into the pores of the AAO. The vertically aligned arrays of CoPt nanowires were about ∼100nm tall with ∼20nm average diameter. Since the CoPt nanowire array is laterally constrained by the surrounding AAO, the nanowire diameter is maintained without coarsening during the L10 phase conversion heat treatment at 700°C. After annealing and conversion to the L10 phase, the ∼20nm CoPt nanowires exhibit a large coercivity of ∼8kOe measured in the in-plane and perpendicular directions.

Ru thin films were deposited by plasma enhanced atomic layer deposition using MethylCyclopentadienylPyrrolylRuthenium (MeCpPy)Ru and N 2 /NH 3 plasma. The growth characteristics have been studied on titanium nitride or tantalum nitride substrates of various thicknesses. On SiO 2 , a large incubation period has been observed, which can be resolved by the use of a metal nitride layer of $ 0.8 nm. The growth characteristics of Ru layers deposited on ultrathin metal nitride layers are similar to those on thick metal nitride substrates despite the fact that the metal nitride layers are not fully closed. Scaled Ru/metal nitride stacks were deposited in narrow lines down to 25 nm width. Thinning of the metal nitride does not impact the conformality of the Ru layer in the narrow lines. For the thinnest lines the Ru deposited on the side wall showed a more granular structure when compared to the bottom of the trench, which is attributed to the plasma directionality during the deposition process.