Work

Controlling compositional homogeneity and crystalline orientation in Bi0.8Sb0.2 thermoelectric thin films

Year: 2015

Type: article

Abstract: Compositional-homogeneity and crystalline-orientation are necessary attributes to achieve high thermoelectric performance in Bi1−xSbx thin films. Following deposition in vacuum, and upon air exposure, we find that 50%–95% of the Sb in 100-nm thick films segregates to form a nanocrystalline Sb2O3 surface layer, leaving the film bulk as Bi-metal. However, we demonstrate that a thin SiN capping layer deposited prior to air exposure prevents Sb-segregation, preserving a uniform film composition. Furthermore, the capping layer enables annealing in forming gas to improve crystalline orientations along the preferred trigonal axis, beneficially reducing electrical resistivity.

Source: APL Materials

DOI: 10.1063/1.4937894

Authors: C. Rochford, D. L. Medlin, K. J. Erickson, M. P. Siegal

Institutions: Sandia National Laboratories California, Sandia National Laboratories

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $2,200