High temperature cross-plane Seebeck coefficient measurement of ErAs:InGaAs/InGaAlAs superlattice

ORAL

Abstract

The 3$\omega $ technique is used to measure the Seebeck coefficient across 2.4 micron superlattices made of 80$\times $((InGaAs)$_{0.6}$(lnAlAs)$_{0.4}$ -10nm / InGaAs-20 nm) films lattice matched to InP substrate. ErAs nanoparticles are randomly distributed inside the 20 nm InGaAs layer. We characterized 4 samples with different doping concentrations (from 2$\times $10$^{18}$ cm$^{-3}$ to 10$^{19}$cm$^{-3})$ in a temperature range of 300K to 600 K. A significant increase in the cross plane Seebeck coefficient compared to the in plane one is observed. Comparison with DC measurement shows that the 3$\omega $ method is more accurate especially at high temperatures. Theoretical analysis based on the solution of the coupled Schr\"{o}dinger and Poisson equations, together with modified Boltzmann transport equation is used to explain the experimental results.

*This work is supported by ONR MURI Thermionic Energy Conversion Center.

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Authors

  • Zhixi Bian

    • Electrical Engineering Department, University of California, Santa Cruz, California 95064
    • Electrical Engineering Department, University of California, Santa Cruz
    • University of California, Santa Cruz

  • Mona Zebarjadi

    • Electrical Engineering Department, University of California, Santa Cruz, California 95064
    • University of California, Santa Cruz

  • Ali Shakouri

    • Electrical Engineering Department, University of California, Santa Cruz, California 95064
    • University of California,Santa Cruz
    • Electrical Engineering Department, University of California, Santa Cruz
    • University of California, Santa Cruz
    • University of California Santa Cruz

  • Gehong Zeng

    • Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106
    • Department of Electrical and Computer Engineering, University of California, Santa Barbara
    • University of California, Santa Barbara

  • John Bowers