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Title: Characterization of electrical properties in axial Si-Ge nanowire heterojunctions using off-axis electron holography and atom-probe tomography

Abstract

Doped Si-Ge nanowire (NW) heterojunctions were grown using the vapor-liquid-solid method with AuGa and Au catalyst particles. Transmission electron microscopy and off-axis electron holography (EH) were used to characterize the nanostructure and to measure the electrostatic potential profile across the junction resulting from electrically active dopants, while atom-probe tomography (APT) was used to determine the Si, Ge and total (active and inactive) dopant concentration profiles. A comparison of the measured potential profile with simulations indicated that Ga dopants unintentionally introduced during AuGa catalyst growth were electronically inactive despite APT results that showed considerable amounts of Ga in the Si region. 10% P in Ge and 100% B in Si were estimated to be activated, which was corroborated by in situ electron-holography biasing experiments. This combination of EH, APT, in situ biasing and simulations allows a better knowledge and understanding of the electrically active dopant distributions in NWs.

Authors:
 [1];  [2];  [3];  [4];  [2];  [2];  [2];  [4];  [2]; ORCiD logo [3];  [1];  [1]
  1. Department of Physics, Arizona State University, Tempe, Arizona 85287, USA
  2. Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
  3. Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
  4. Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pennsylvania 15261, USA
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1340784
Report Number(s):
PNNL-SA-106309
Journal ID: ISSN 0021-8979; JAPIAU; 47607; KP1704020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 10
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Gan, Zhaofeng, Perea, Daniel E., Yoo, Jinkyoung, He, Yang, Colby, Robert J., Barker, Josh E., Gu, Meng, Mao, Scott X., Wang, Chongmin, Picraux, S. T., Smith, David J., and McCartney, Martha R.. Characterization of electrical properties in axial Si-Ge nanowire heterojunctions using off-axis electron holography and atom-probe tomography. United States: N. p., 2016. Web. doi:10.1063/1.4962380.
Gan, Zhaofeng, Perea, Daniel E., Yoo, Jinkyoung, He, Yang, Colby, Robert J., Barker, Josh E., Gu, Meng, Mao, Scott X., Wang, Chongmin, Picraux, S. T., Smith, David J., & McCartney, Martha R.. Characterization of electrical properties in axial Si-Ge nanowire heterojunctions using off-axis electron holography and atom-probe tomography. United States. doi:10.1063/1.4962380.
Gan, Zhaofeng, Perea, Daniel E., Yoo, Jinkyoung, He, Yang, Colby, Robert J., Barker, Josh E., Gu, Meng, Mao, Scott X., Wang, Chongmin, Picraux, S. T., Smith, David J., and McCartney, Martha R.. 2016. "Characterization of electrical properties in axial Si-Ge nanowire heterojunctions using off-axis electron holography and atom-probe tomography". United States. doi:10.1063/1.4962380.
@article{osti_1340784,
title = {Characterization of electrical properties in axial Si-Ge nanowire heterojunctions using off-axis electron holography and atom-probe tomography},
author = {Gan, Zhaofeng and Perea, Daniel E. and Yoo, Jinkyoung and He, Yang and Colby, Robert J. and Barker, Josh E. and Gu, Meng and Mao, Scott X. and Wang, Chongmin and Picraux, S. T. and Smith, David J. and McCartney, Martha R.},
abstractNote = {Doped Si-Ge nanowire (NW) heterojunctions were grown using the vapor-liquid-solid method with AuGa and Au catalyst particles. Transmission electron microscopy and off-axis electron holography (EH) were used to characterize the nanostructure and to measure the electrostatic potential profile across the junction resulting from electrically active dopants, while atom-probe tomography (APT) was used to determine the Si, Ge and total (active and inactive) dopant concentration profiles. A comparison of the measured potential profile with simulations indicated that Ga dopants unintentionally introduced during AuGa catalyst growth were electronically inactive despite APT results that showed considerable amounts of Ga in the Si region. 10% P in Ge and 100% B in Si were estimated to be activated, which was corroborated by in situ electron-holography biasing experiments. This combination of EH, APT, in situ biasing and simulations allows a better knowledge and understanding of the electrically active dopant distributions in NWs.},
doi = {10.1063/1.4962380},
journal = {Journal of Applied Physics},
number = 10,
volume = 120,
place = {United States},
year = 2016,
month = 9
}
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