Direct Probing of Cross-Plane Thermal Properties of Atomic Layer Deposition Al 2 O 3 /ZnO Superlattice Films with an Improved Figure of Merit and Their Cross-Plane Thermoelectric Generating Performance

No Won Park, Won Yong Lee, Yo Seop Yoon, Jay Young Ahn, Jung Hoon Lee, Gil Sung Kim, Tae Geun Kim, Chel Jong Choi, Jin Seong Park, Eiji Saitoh, Sang Kwon Lee

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)

Abstract

There is a recent interest in semiconducting superlattice films because their low dimensionality can increase the thermal power and phonon scattering at the interface in superlattice films. However, experimental studies in all cross-plane thermoelectric (TE) properties, including thermal conductivity, Seebeck coefficient, and electrical conductivity, have not been performed from these semiconducting superlattice films because of substantial difficulties in the direct measurement of the Seebeck coefficient and electrical conductivity. Unlike the conventional measurement method, we present a technique using a structure of sandwiched superlattice films between two embedded heaters as the heating source, and electrodes with two Cu plates, which directly enables the investigation of the Seebeck coefficient and electrical conductivity across the Al 2 O 3 /ZnO superlattice films, prepared by the atomic layer deposition method. Used in combination with the promising cross-plane four-point probe 3-ω method, our measurements and analysis demonstrate all cross-plane TE properties of Al 2 O 3 /ZnO superlattice films in the temperature range of 80 to 500 K. Our experimental methodology and the obtained results represent a significant advancement in the understanding of phonons and electrical transports in nanostructured materials, especially in semiconducting superlattice films in various temperature ranges.

Original languageEnglish
Pages (from-to)44472-44482
Number of pages11
JournalACS Applied Materials and Interfaces
Volume10
Issue number51
DOIs
Publication statusPublished - 2018 Dec 26

Bibliographical note

Funding Information:
This study was supported by the Priority Research Centers Program and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2016R1A2B2012909 and 2016R1A3B1908249).

Publisher Copyright:
Copyright © 2018 American Chemical Society.

Keywords

  • 3-ω measurement
  • Seebeck coefficient
  • cross-plane thermoelectric properties
  • phonon scattering
  • phonon transport
  • superlattice films
  • thermal conductivity

ASJC Scopus subject areas

  • General Materials Science

Fingerprint

Dive into the research topics of 'Direct Probing of Cross-Plane Thermal Properties of Atomic Layer Deposition Al 2 O 3 /ZnO Superlattice Films with an Improved Figure of Merit and Their Cross-Plane Thermoelectric Generating Performance'. Together they form a unique fingerprint.

Cite this