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Title: Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition

Abstract

Heterostructuring provides novel opportunities for exploring emergent phenomena and applications by developing designed properties beyond those of homogeneous materials. Advances in nanoscience enable the preparation of heterostructures formed incommensurate materials. Two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides, are of particular interest due to their distinct physical characteristics. There have been recent changes in new research areas related to 2D/2D heterostructures. But, other heterostructures such as 2D/three-dimensional (3D) materials have not been thoroughly studied yet although the growth of 3D materials on 2D materials creating 2D/3D heterostructures with exceptional carrier transport properties has been reported. Here also we report a novel heterostructure composed of Ge and monolayer MoS 2, prepared by chemical vapor deposition. A single crystalline Ge (110) thin film was grown on monolayer MoS 2. The electrical characteristics of Ge and MoS 2 in the Ge/MoS 2 heterostructure were remarkably different from those of isolated Ge and MoS 2. The field-effect conductivity type of the monolayer MoS 2 is converted from n-type to p-type by growth of the Ge thin film on top of it. Undoped Ge on MoS 2 is highly conducting. The observations can be explained by charge transfer in the heterostructure as opposedmore » to chemical doping via the incorporation of impurities, based on our first-principles calculations.« less

Authors:
 [1];  [2]; ORCiD logo [3];  [4];  [5];  [6]; ORCiD logo [3];  [7]; ORCiD logo [7]; ORCiD logo [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Center for Integrated Nanotechnologies
  2. Northeastern Univ., Boston, MA (United States). Dept. of Physics; Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Physics and Applications-11
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Univ. of California, San Diego, CA (United States). Dept. of Electrical and Computer Engineering
  5. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies
  6. Northeastern Univ., Boston, MA (United States). Dept. of Physics
  7. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Physics and Applications-11
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1375868
Report Number(s):
LA-UR-16-22544
Journal ID: ISSN 2040-3364; NANOHL
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nanoscale
Additional Journal Information:
Journal Volume: 8; Journal Issue: 44; Journal ID: ISSN 2040-3364
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Material Science

Citation Formats

Lin, Yung-Chen, Bilgin, Ismail, Ahmed, Towfiq, Chen, Renjie, Pete, Doug, Kar, Swastik, Zhu, Jian-Xin, Gupta, Gautam, Mohite, Aditya, and Yoo, Jinkyoung. Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition. United States: N. p., 2016. Web. doi:10.1039/C6NR03621J.
Lin, Yung-Chen, Bilgin, Ismail, Ahmed, Towfiq, Chen, Renjie, Pete, Doug, Kar, Swastik, Zhu, Jian-Xin, Gupta, Gautam, Mohite, Aditya, & Yoo, Jinkyoung. Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition. United States. doi:10.1039/C6NR03621J.
Lin, Yung-Chen, Bilgin, Ismail, Ahmed, Towfiq, Chen, Renjie, Pete, Doug, Kar, Swastik, Zhu, Jian-Xin, Gupta, Gautam, Mohite, Aditya, and Yoo, Jinkyoung. 2016. "Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition". United States. doi:10.1039/C6NR03621J. https://www.osti.gov/servlets/purl/1375868.
@article{osti_1375868,
title = {Charge transfer in crystalline germanium/monolayer MoS 2 heterostructures prepared by chemical vapor deposition},
author = {Lin, Yung-Chen and Bilgin, Ismail and Ahmed, Towfiq and Chen, Renjie and Pete, Doug and Kar, Swastik and Zhu, Jian-Xin and Gupta, Gautam and Mohite, Aditya and Yoo, Jinkyoung},
abstractNote = {Heterostructuring provides novel opportunities for exploring emergent phenomena and applications by developing designed properties beyond those of homogeneous materials. Advances in nanoscience enable the preparation of heterostructures formed incommensurate materials. Two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides, are of particular interest due to their distinct physical characteristics. There have been recent changes in new research areas related to 2D/2D heterostructures. But, other heterostructures such as 2D/three-dimensional (3D) materials have not been thoroughly studied yet although the growth of 3D materials on 2D materials creating 2D/3D heterostructures with exceptional carrier transport properties has been reported. Here also we report a novel heterostructure composed of Ge and monolayer MoS2, prepared by chemical vapor deposition. A single crystalline Ge (110) thin film was grown on monolayer MoS2. The electrical characteristics of Ge and MoS2 in the Ge/MoS2 heterostructure were remarkably different from those of isolated Ge and MoS2. The field-effect conductivity type of the monolayer MoS2 is converted from n-type to p-type by growth of the Ge thin film on top of it. Undoped Ge on MoS2 is highly conducting. The observations can be explained by charge transfer in the heterostructure as opposed to chemical doping via the incorporation of impurities, based on our first-principles calculations.},
doi = {10.1039/C6NR03621J},
journal = {Nanoscale},
number = 44,
volume = 8,
place = {United States},
year = 2016,
month = 9
}

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