title: DEVICE TECHNOLOGY. Phase patterning for ohmic homojunction contact in MoTe₂.
abstract: Artificial van der Waals heterostructures with two-dimensional (2D) atomic crystals are promising as an active channel or as a buffer contact layer for next-generation devices. However, genuine 2D heterostructure devices remain limited because of impurity-involved transfer process and metastable and inhomogeneous heterostructure formation. We used laser-induced phase patterning, a polymorph engineering, to fabricate an ohmic heterophase homojunction between semiconducting hexagonal (2H) and metallic monoclinic (1T') molybdenum ditelluride (MoTe2) that is stable up to 300°C and increases the carrier mobility of the MoTe2 transistor by a factor of about 50, while retaining a high on/off current ratio of 10(6). In situ scanning transmission electron microscopy results combined with theoretical calculations reveal that the Te vacancy triggers the local phase transition in MoTe2, achieving a true 2D device with an ohmic contact.
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Suyeon
authors.initials: S
authors.lastname: Cho
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Sera
authors.initials: S
authors.lastname: Kim
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Kim
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Jiong
authors.initials: J
authors.lastname: Zhao
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Jinbong
authors.initials: J
authors.lastname: Seok
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Keum
authors.affiliation: Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Jaeyoon
authors.initials: J
authors.lastname: Baik
authors.affiliation: Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
authors.forename: Duk-Hyun
authors.initials: DH
authors.lastname: Choe
authors.affiliation: Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
authors.forename: K J
authors.initials: KJ
authors.lastname: Chang
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan.
authors.forename: Kazu
authors.initials: K
authors.lastname: Suenaga
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea. kimsungwng@skku.edu leeyoung@skku.edu h.yang@skku.edu.
authors.forename: Sung Wng
authors.initials: SW
authors.lastname: Kim
authors.affiliation: IBS Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science, Sungkyunkwan University, Suwon 440-746, Korea. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea. kimsungwng@skku.edu leeyoung@skku.edu h.yang@skku.edu.
authors.forename: Young Hee
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea. kimsungwng@skku.edu leeyoung@skku.edu h.yang@skku.edu.
authors.forename: Heejun
authors.initials: H
authors.lastname: Yang