2024

Vol.31 No.3

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  • Journal of the Microelectronics and Packaging Society
  • Volume 31(1); 2024
  • Article

Review

Journal of the Microelectronics and Packaging Society 2024;31(1):43-48. Published online: May, 10, 2024

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DOI : doi.org/10.6117/kmeps.2024.31.1.043

Electrical Properties of Two-dimensional Electron Gas at the Interface of LaAlO3/SrTiO3 by a Solution-based Process

  • Kyunghee Ryu1 , Sanghyeok Ryou2 , Hyeonji Cho1 , Hyunsoo Ahn3 , Jong Hoon Jung3 , Hyungwoo Lee2,4,†, and Jung-Woo Lee1,†
    1Department of Materials Science and Engineering Hongik University, Sejong 30016 Republic of Korea, 2Department of Energy Systems Research, Ajou University, Suwon 16499 Republic of Korea, 3Department of Physics, Inha University, Incheon 22212 Republic of Korea, 4Department of Physics, Ajou University, Suwon 16499 Republic of Korea
Corresponding author E-mail: jungwoo@hongik.ac.kr, hyungwoo@ajou.ac.kr
Abstract

: The discovery of a two-dimensional electron gas (2DEG) at the interface of LaAlO3 (LAO) and SrTiO3 (STO) substrates has sparked significant interest, providing a foundation for cutting-edge research in electronic devices based on complex oxide heterostructures. However, conventional methods for producing LAO thin films, typically employing techniques like pulsed laser deposition (PLD) within physical vapor deposition (PVD), are associated with high costs and challenges in precisely controlling the La and Al composition within LAO. In this study, we adopted a cost-effective alternative approach—solution-based processing—to fabricate LAO thin films and investigated their electrical properties. By adjusting the concentration of the precursor solution, we varied the thickness of LAO films from 2 to 65 nm and determined the sheet resistance and carrier density for each thickness. After vacuum annealing, the sheet resistance of the conductive channel ranged from 0.015 to 0.020 Ω·sq⁻¹, indicating that electron conduction occurs not only at the LAO/STO interface but also into the STO bulk region, consistent with previous studies. These findings demonstrate the successful formation and control of 2DEG through solution-based processing, offering the potential to reduce process costs and broaden the scope of applications in electronic device manufacturing.

Keywords Complex oxide thin films, SrTiO3, LaAlO3, Two-dimensional electron gas, Solution-based process

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