title: Thermal stability of 2DEG at amorphous LaAlO3/crystalline SrTiO3heterointerfaces.
abstract: At present, the generation of heterostructures with two dimensional electron gas (2DEG) in amorphous LaAlO3(a-LAO)/SrTiO3(STO) has been achieved. Herein, we analysed thermal stability of 2DEG at a-LAO/STO interfaces in comparison with 2DEG at crystalline LaAlO3(c-LAO)/STO interfaces. To create 2DEG at LAO/STO interface, regardless of growing temperature from 25 to 700 °C, we found that environment with oxygen deficient during the deposition of LAO overlayer is essentially required. That indicates that the oxygen-poor condition in the system is more essential than the crystalline nature of LAO layer. 2DEG at a-LAO/STO interface is depleted upon ex situ annealing at 300 °C under 300 Torr of oxygen pressure, while that in c-LAO/STO interface is still maintained. Our result suggests that the LAO overlayer crystallinity critically affects the thermal-annealing-induced depletion of 2DEG at a-LAO/STO interface rather than the generation of 2DEG. We clearly provide that amorphous TiOxcan efficiently prevent the thermal degradation of 2DEG at the a-LAO/STO interface, which gives a cornerstone for achieving thermal-stable 2DEG at a-LAO/STO interface.
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, 136-791 Republic of Korea.|Department of Materials Science and Engineering, Yonsei University, Seoul, 120-749 Republic of Korea.
authors.forename: Seon Young
authors.initials: SY
authors.lastname: Moon
authors.affiliation: Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744 Republic of Korea.
authors.forename: Cheon Woo
authors.initials: CW
authors.lastname: Moon
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, 136-791 Republic of Korea.|Department of Nanomaterials Science and Technology, Korea University of Science and Technology, Daejeon, 305-350 Republic of Korea.
authors.forename: Hye Jung
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744 Republic of Korea.
authors.forename: Taemin
authors.initials: T
authors.lastname: Kim
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, 136-791 Republic of Korea.|Department of Nanomaterials Science and Technology, Korea University of Science and Technology, Daejeon, 305-350 Republic of Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 136-701 Republic of Korea.
authors.forename: Chong-Yun
authors.initials: CY
authors.lastname: Kang
authors.affiliation: Department of Materials Science and Engineering, Yonsei University, Seoul, 120-749 Republic of Korea.
authors.forename: Heon-Jin
authors.initials: HJ
authors.lastname: Choi
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, 136-791 Republic of Korea.
authors.forename: Jin-Sang
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, 136-791 Republic of Korea.|Department of Nanomaterials Science and Technology, Korea University of Science and Technology, Daejeon, 305-350 Republic of Korea.
authors.forename: Seung-Hyub
authors.initials: SH
authors.lastname: Baek
authors.affiliation: Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 151-744 Republic of Korea.
authors.forename: Ho Won
authors.initials: HW
authors.lastname: Jang
keywords: 2-Dimensional electron gas; Interface; Oxide; Thermal stability