Electrodeposition of nanowire array in porous anodic alumina (PAA) templates combine the performance benefits offered by crystallographic texture control, lattice thermal conductivity suppression through boundary scattering of phonons, elastic relaxation of misfit strain, and scalablity essential for high efficiency thermoelectric devices. The template material, however, can serve as a thermal shunt thereby reducing the effective thermoelectric performance. Here, we demonstrate a process of minimizing the parasitic thermal conduction by replacing the PAA matrix with SU-8 (κ∼0.2 W/m K). We report a reduction in the performance penalty from 27% for Bi2Te3/PAA to ∼5% for Bi2Te3/SU-8 nanocomposite by thermal conductivity measurements using a photoacoustic technique.

A procedure to fabricate a highly ordered electrodeposited nanowire array in a porous anodic alumina template with nanowires of uniform length and exposed tips for establishing low‐resistance ohmic contacts has been demonstrated. In this work, contacts to Au nanowire arrays have been investigated as a model system. The structural, topographical and electrical characteristics of the nanowire array have been studied using field emission scanning electron microscopy and conductive atomic force microscopy. Measurements showed that an electrical contact between the conducting AFM probe and the exposed Au nanowire tips was initiated only after a force of 14.4 ± 2 nN was applied. The I –V characteristics were linear up to the maximum applied current density of 1.5 × 1012 A/m2, and the resistivity of the individual Au nanowires in the template was estimated to be between 1.4 and 7 times the resistivity of large grained bulk Au. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

A scalable electrochemical process for addressing the thermomechanical compliance and contact resistance at metal/thermoelectric (M/TE) interfaces by integrating TE films with carbon nanotube (CNT) arrays is presented. Thermomechanical compliance and thermal contact characteristics of TE/CNT/M and TE/M contacts are compared. A process‐flow for patterned electrodeposition of TE films on CNT arrays coated surfaces is also demonstrated.

Templated synthesis of thermoelectric nanowires in porous anodic alumina (PAA) have potential for enhanced performance relative to bulk materials. A significant challenge is the template material, which can serve as a thermal shunt. In this work, an approach for creating a branched PAA template is described. The process utilizes localized self-heating to destabilize the planar anodization front, yielding branched and interconnected pores growing at a rate of 300 μm/h. The template is selectively etched after electrodeposition of desired materials, yielding self-supporting nanowire arrays with thicknesses up to about 300 μm, thereby eliminating the thermal shunt through the template.