Thermoelectric properties of nanocrystalline Bi3Se2Te thin films grown using pulsed laser deposition

Le Thi Cam Tuyen, Phuoc Huu Le, Chih-Wei Luo*, Jih-Perng Leu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

Abstract

This study reports the material and thermoelectric properties of n-type nanocrystalline Bi-Se-Te thin films grown using pulse laser deposition (PLD) with a Bi2Se2Te single crystal as the target. In order to optimize the transport and thermoelectric properties, Bi-Se-Te thin films are fabricated by maintaining the substrate temperature (TS) between 200 and 350 °C and a helium gas pressure (PHe) from 0.027 to 86.7 Pa. Unlike the target, all deposited films unexpectedly exhibit Bi3Se2Te phase with highly c-axis orientation, because of the high re-evaporation rates of Se and Te at the elevated TS ≥ 200 °C. The estimated grain (crystalline) size ranges between 18.4 and 39.4 nm, and this monotonically increases as TS increases. The Bi3Se2Te films demonstrate excellent electrical conductivities owning to the high carrier concentration in the order of 1020 cm-3. A window of deposition conditions for high thermoelectric power factors (PF) is TS of 250-350 °C and PHe of 40 Pa. The optimal PF is 8.3 μW/cmK2 for the Bi3Se2Te film prepared at 250 °C and 40 Pa.

Original languageEnglish
Pages (from-to)107-114
Number of pages8
JournalJournal of Alloys and Compounds
Volume673
DOIs
StatePublished - 15 Jul 2016

Keywords

  • BiSeTe
  • Nanocrystalline films
  • Power factor
  • Pulse laser deposition
  • Thermoelectric
  • DIRAC FERMIONS
  • GRAIN-SIZE
  • SURFACE
  • BI2TE3
  • MICROSTRAIN
  • OXIDATION
  • ELECTRON
  • FIGURE
  • MERIT
  • POWER

Fingerprint Dive into the research topics of 'Thermoelectric properties of nanocrystalline Bi<sub>3</sub>Se<sub>2</sub>Te thin films grown using pulsed laser deposition'. Together they form a unique fingerprint.

Cite this