논문 해외 국제전문학술지(SCI급) Antisite defects in n-type Bi-2(Te,Se)(3): Experimental and theoretical studies
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2014-04
- 저자명 오민욱
- 학술지명 JOURNAL OF APPLIED PHYSICS
- 발행처명 AMER INST PHYSICS
- 발행국가 해외
- 논문언어 외국어
- 전체저자수 6
홈페이지논문 초록 (Abstract)
Intrinsic defects in Bi2Te3 were analyzed using first-principles density functional theory calculations. The results demonstrated that antisite defects were dominant in both p- and n-type Bi2Te3. To investigate the characteristics of these defects, n-type Bi-2(Te,Se)(3) compounds were fabricated using powder prepared by high-energy ball milling and their electrical properties were examined. Electrical resistivity and the Seebeck coefficient increased with ball milling time. These changes in both properties were attributed to a reduction in the carrier concentration, which was supported by the Hall coefficient measurement. The antisite defects were found to be responsible for the changes in carrier concentration. Lattice parameter analysis supported the postulate that variations in the concentration of antisite defects were responsible for the changes in carrier concentration. These findings suggest that optimization of carrier concentration should be considered in the high-energy ball milling process, in which reductions in grain size are expected to improve thermoelectric properties. (C) 2014 AIP Publishing LLC.