Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (49권1호 40-45)

Study on Thermoelectric Properties of Cu Doping of Pulse-Electrodeposited n-type Bi2(Te-Se)3 Thin Films

펄스 전기도금법에 의해 제조된 n형 Bi2(Te-Se)3 박막의 Cu 도핑에 따른 열전특성에 관한 연구

허나리;김광호;임재홍;
Heo, Na-Ri;Kim, Kwang-Ho;Lim, Jae-Hong;

부산대학교, 재료공학부;한국재료연구소, 표면기술본부;
Pusan National University, Department of Materials Science and Engineering;Korea Institute of Materials Science(KIMS), Surface Technology Division;

DOI : 10.5695/JKISE.2016.49.1.40

Abstract

Recently, $Bi_2Te_3$-based alloys are the best thermoelectric materials near to room temperature, so it has been researched to achieve increased figure of merit(ZT). Ternary compounds such as Bi-Te-Se and Bi-Sb-Te have higher thermoelectric property than binary compound Bi-Te and Sb-Te, respectively. Compared to DC plating method, pulsed electrodeposition is able to control parameters including average current density, and on/off pulse time etc. Thereby the morphology and properties of the films can be improved. In this study, we electrodeposited n-type ternary Cu-doped $Bi_2(Te-Se)_3$ thin film by modified pulse technique at room temperature. To further enhance thermoelectric properties of $Bi_2(Te-Se)_3$ thin film, we optimized Cu doping concentration in $Bi_2(Te-Se)_3$ thin film and correlated it to electrical and thermoelectric properties. Thus, the crystal, electrical, and thermoelectric properties of electrodeposited $Bi_2(Te-Se)_3$ thin film were characterized the XRD, SEM, EDS, Seebeck measurement, and Hall effect measurement, respectively. As a result, the thermoelectric properties of Cu-doped $Bi_2(Te-Se)_3$ thin films were observed that the Seebeck coefficient is $-101.2{mu}V/K$ and the power factor is $1412.6{mu}W/mK^2$ at 10 mg of Cu weight. The power factor of Cu-doped $Bi_2(Te-Se)_3$ thin film is 1.4 times higher than undoped $Bi_2(Te-Se)_3$ thin film.

Keywords

Electrodeposition;$Bi_2(Te-Se)_3$;modified Pulse electrodeposition;Cu;Doping;n-type thin film;