Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films

doi:10.1063/1.4979785

Title: Correlating thermoelectric properties with microstructure in Bi _0.8 Sb _0.2 thin films

The room temperature electronic transport properties of 100 nm-thick thermoelectric Bi _0.8Sb _0.2 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. Furthermore, 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. Our resulting values are similar to single crystals and significantly better than previous reports from films and polycrystalline bulk alloys.

Authors:

Siegal, M. P. ^[1] ; Lima-Sharma, A. L. ^[1] ; Sharma, P. A. ^[1] ;

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Publication Date:: 2017-04-03

Report Number(s):: SAND2017-0986J
Journal ID: ISSN 0003-6951; 650830

Grant/Contract Number:: AC04-94AL85000

Type:: Accepted Manuscript

Journal Name:: Applied Physics Letters

Additional Journal Information:: Journal Volume: 110; Journal Issue: 14; Journal ID: ISSN 0003-6951

Publisher:: American Institute of Physics (AIP)

Research Org:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org:: USDOE National Nuclear Security Administration (NNSA)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

OSTI Identifier:: 1357018


                    Siegal, M. P., Lima-Sharma, A. L., Sharma, P. A., and Rochford, C.. Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films.  United States: N. p.,  
        Web.  doi:10.1063/1.4979785.

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                    Siegal, M. P., Lima-Sharma, A. L., Sharma, P. A., & Rochford, C.. Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films.  United States.  doi:10.1063/1.4979785.

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                    Siegal, M. P., Lima-Sharma, A. L., Sharma, P. A., and Rochford, C.. 2017.  
        "Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films".  United States.  
        doi:10.1063/1.4979785.  https://www.osti.gov/servlets/purl/1357018.

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@article{osti_1357018,

  title        = {Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films},

  author       = {Siegal, M. P. and Lima-Sharma, A. L. and Sharma, P. A. and Rochford, C.},

  abstractNote = {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. Furthermore, 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. Our resulting values are similar to single crystals and significantly better than previous reports from films and polycrystalline bulk alloys.},

  doi          = {10.1063/1.4979785},

  journal      = {Applied Physics Letters},

  number       = 14,

  volume       = 110,

  place        = {United States},

  year         = {2017},

  month        = {4}

}

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Free Publicly Accessible Full Text
Accepted Manuscript (DOE)
Publisher's Version of Record
10.1063/1.4979785
https://doi.org/10.1063/1.4979785

Works referenced in this record:

Thermoelectric figure of merit of a one-dimensional conductor
journal, June 1993

Hicks, L. D.; Dresselhaus, M. S.
Physical Review B, Vol. 47, Issue 24, p. 16631-16634
DOI: 10.1103/PhysRevB.47.16631

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Title: Correlating thermoelectric properties with microstructure in Bi 0.8 Sb 0.2 thin films

Access journal articles and accepted manuscripts
resulting from DOE research funding

Title: Correlating thermoelectric properties with microstructure in Bi _0.8 Sb _0.2 thin films