Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
권호 표지
DOI QR코드

DOI QR Code

Dependence of LaAlO3/SrTiO3 Interfacial Conductivity on the Thickness of LaAlO3 Layer Investigated by Current-voltage Characteristics

LaAlO3 두께에 따른 LaAlO3/SrTiO3 계면에서의 전류-전압 특성을 이용한 전도성 변화 연구

  • Moon, Seon-Young (Electronic Materials Center, Korea Institute of Science and Technology (KIST)) ;
  • Baek, Seung-Hyub (Electronic Materials Center, Korea Institute of Science and Technology (KIST)) ;
  • Kang, Chong-Yun (Electronic Materials Center, Korea Institute of Science and Technology (KIST)) ;
  • Choi, Ji-Won (Electronic Materials Center, Korea Institute of Science and Technology (KIST)) ;
  • Choi, Heon-Jin (Department of Materials Science and Engineering, Yonsei University) ;
  • Kim, Jin-Sang (Department of Materials Science and Engineering, Yonsei University) ;
  • Jang, Ho-Won (Department of Materials Science and Engineering, Seoul National University)
  • 문선영 (한국과학기술연구원 전자재료연구센터) ;
  • 백승협 (한국과학기술연구원 전자재료연구센터) ;
  • 강종윤 (한국과학기술연구원 전자재료연구센터) ;
  • 최지원 (한국과학기술연구원 전자재료연구센터) ;
  • 최헌진 (연세대학교 신소재공학과) ;
  • 김진상 (연세대학교 신소재공학과) ;
  • 장호원 (서울대학교 재료공학과)
  • Received : 2012.07.05
  • Accepted : 2012.07.24
  • Published : 2012.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

Oxides possess several interesting properties, such as ferroelectricity, magnetism, superconductivity, and multiferroic behavior, which can effectively be used oxide electronics based on epitaxially grown heterostructures. The microscopic properties of oxide interfaces may have a strong impact on the electrical transport properties of these heterostructures. It was recently demonstrated that high electrical conductivity and mobility can be achieved in the system of an ultrathin $LaAlO_3$ film deposited on a $TiO_2$-terminated $SrTiO_3$ substrate, which was a remarkable result because the conducting layer was at the interface between two insulators. In this study, we observe that the current-voltage characteristics exhibit $LaAlO_3$ thickness dependence of electrical conductivity in $TiO_2$-terminated $SrTiO_3$. We find that the $LaAlO_3$ layers with a thickness of up 3 unit cells, result in highly insulating interfaces, whereas those with thickness of 4 unit cells and above result in conducting interfaces.

Keywords

References

  1. H. Iwai, Microelectron. Eng., 86, 1520 (2009). https://doi.org/10.1016/j.mee.2009.03.129
  2. Ian Osborne, M. Laving, and R. Coontz, Science, 327, 1595 (2010). https://doi.org/10.1126/science.327.5973.1595
  3. H. Takagi and H. Y. Hwang, Science, 327, 601 (2010).
  4. M. Baibich, J. Broto, A. Fert, F. Vandau, F. Petroff, P. Eitenne, G. Creuzet, A. Frederich, and J. Chazelas, Phys. Rev. Lett., 61, 2472 (1988). https://doi.org/10.1103/PhysRevLett.61.2472
  5. G. Rijnders and D. H. A. Blank, Nature, 433, 369 (2005). https://doi.org/10.1038/433369a
  6. A. Ohtomo and H. Y. Hwang, Nature, 427, 423 (2004). https://doi.org/10.1038/nature02308
  7. G. Koster, B. L. Kropman, G. J. H. M. Rijnders D. H. A. Blank, and H. Rogalla, Appl. Phys. Lett., 73, 2920 (1998). https://doi.org/10.1063/1.122630
  8. N. Nakagawa, H. Y. Hwang, and A. Muller, Nature, 5, 204 (2006). https://doi.org/10.1038/nmat1569
  9. S. Thiel, G. Hammerl, A. Schmehl, C. W. Schneider, and J. Mannhart, Science, 313, 1942 (2006). https://doi.org/10.1126/science.1131091