標題: Thermoelectric properties of nanocrystalline Bi3Se2Te thin films grown using pulsed laser deposition
作者: Tuyen, Le Thi Cam
Phuoc Huu Le
Luo, Chih Wei
Leu, Jihperng
材料科學與工程學系
電子物理學系
Department of Materials Science and Engineering
Department of Electrophysics
關鍵字: Bi3Se2Te;Thermoelectric;Nanocrystalline films;Power factor;Pulse laser deposition
公開日期: 15-七月-2016
摘要: 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 (T-S) between 200 and 350 degrees C and a helium gas pressure (P-He) from 0.027 to 86.7 Pa. Unlike the target, all deposited films unexpectedly exhibit Bi2Se2Te phase with highly c-axis orientation, because of the high re-evaporation rates of Se and Te at the elevated T-S >= 200 degrees 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 10(20) cm(-3). A window of deposition conditions for high thermoelectric power factors (PF) is T-S of 250-350 degrees C and P-He of 40 Pa. The optimal PF is 8.3 mu W/cmK(2) for the Bi3Se2Te film prepared at 250 degrees C and 40 Pa. (C) 2016 Elsevier B.V. All rights reserved.
URI: http://dx.doi.org/10.1016/j.jallcom.2016.03.006
http://hdl.handle.net/11536/133397
ISSN: 0925-8388
DOI: 10.1016/j.jallcom.2016.03.006
期刊: JOURNAL OF ALLOYS AND COMPOUNDS
Volume: 673
起始頁: 107
結束頁: 114
顯示於類別:期刊論文