Year: 2017
Type: article
Abstract: The room temperature electronic transport properties of 100 nm-thick thermoelectric Bi0.8Sb0.2 films, sputter-deposited onto quartz substrates and post-annealed in an ex-situ furnace, systematically correlate with the overall microstructural quality, improving with increasing annealing temperature until close to the melting point for the alloy composition. The optimized films have high crystalline quality with ∼99% of the grains oriented with the trigonal axis perpendicular to the substrate surface. Film resistivities and Seebeck coefficients are accurately measured by preventing deleterious surface oxide formation via a SiN capping layer and using Nd-doped Al for contacts. The resulting values are similar to single crystals and significantly better than previous reports from films and polycrystalline bulk alloys.
Source: Applied Physics Letters
DOI: 10.1063/1.4979785
Institution: Sandia National Laboratories
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2604415056