TY - JOUR
T1 - Esaki Diodes Based on 2-D/3-D Heterojunctions
AU - Xu, Kai
AU - Cai, Yuhang
AU - Zhu, Wenjuan
N1 - Funding Information:
Manuscript received April 5, 2018; revised June 5, 2018 and July 13, 2018; accepted July 21, 2018. Date of current version September 20, 2018. This work was supported in part by the National Science Foundation, Electrical, Communications and Cyber Systems under Grant 16-11279 and in part by the Office of Naval Research under Grant NAVY N00014-17-1-2973. The review of this paper was arranged by Editor J. T. Teherani. (Corresponding author: Wenjuan Zhu.) K. Xu and W. Zhu are with the Department of Electrical and Computer Engineering, University of Illinois at Urbana–Champaign, Champaign, IL 61801 USA (e-mail: wjzhu@illinois.edu).
Publisher Copyright:
© 1963-2012 IEEE.
PY - 2018/10
Y1 - 2018/10
N2 - Esaki diodes based on interband tunneling have the characteristics of negative differential resistance (NDR) and ultrafast transient time, which lead to broad applications including oscillators, multivalue memories, and terahertz detectors. In this paper, we present the first demonstration of Esaki diodes based on 2-D/3-D heterojunctions - more specifically, chemical vapor deposition MoS2 on degenerately doped silicon. As compared to traditional 3-D heterostructures, these 2-D/3-D heterostructures have the following advantages: dislocation-free 2-D crystals even when the lattices are mismatched, dangling bond-free surface, and capability for large-scale synthesis at low cost. In this paper, monolayer, bilayer, and trilayer MoS2 are synthesized directly on degenerated Si substrate, forming the ultraclean heterostructures without surface contamination from tape and resist. Based on these pristine heterostructures, we are able to observe prominent NDR effect at room temperature. This NDR effect is attributed to the degenerately p-type doping in silicon and the natural n-type doping in MoS2. We also found that the peak voltage corresponding to the local maximum tunneling current depends on the MoS2 thickness. While MoS2 is changing from the monolayer (0.7 nm) to bulk (9.5 nm), the peak voltage increases from 0.8 to 1.6 V. This phenomenon can be explained by the energy-level differences between the monolayer and bulk MoS2. This paper provides the experimental groundwork for the synthesis of transition metal dichalcogenides on degenerately doped Si substrates and opens up new and exciting opportunities for electronic applications of 2-D/3-D heterostructures.
AB - Esaki diodes based on interband tunneling have the characteristics of negative differential resistance (NDR) and ultrafast transient time, which lead to broad applications including oscillators, multivalue memories, and terahertz detectors. In this paper, we present the first demonstration of Esaki diodes based on 2-D/3-D heterojunctions - more specifically, chemical vapor deposition MoS2 on degenerately doped silicon. As compared to traditional 3-D heterostructures, these 2-D/3-D heterostructures have the following advantages: dislocation-free 2-D crystals even when the lattices are mismatched, dangling bond-free surface, and capability for large-scale synthesis at low cost. In this paper, monolayer, bilayer, and trilayer MoS2 are synthesized directly on degenerated Si substrate, forming the ultraclean heterostructures without surface contamination from tape and resist. Based on these pristine heterostructures, we are able to observe prominent NDR effect at room temperature. This NDR effect is attributed to the degenerately p-type doping in silicon and the natural n-type doping in MoS2. We also found that the peak voltage corresponding to the local maximum tunneling current depends on the MoS2 thickness. While MoS2 is changing from the monolayer (0.7 nm) to bulk (9.5 nm), the peak voltage increases from 0.8 to 1.6 V. This phenomenon can be explained by the energy-level differences between the monolayer and bulk MoS2. This paper provides the experimental groundwork for the synthesis of transition metal dichalcogenides on degenerately doped Si substrates and opens up new and exciting opportunities for electronic applications of 2-D/3-D heterostructures.
KW - 2-D/3-D heterojunctions
KW - Esaki diodes
KW - MoS
KW - chemical vapor deposition (CVD)
KW - degenerately doped silicon
UR - http://www.scopus.com/inward/record.url?scp=85053317328&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85053317328&partnerID=8YFLogxK
U2 - 10.1109/TED.2018.2867337
DO - 10.1109/TED.2018.2867337
M3 - Article
AN - SCOPUS:85053317328
SN - 0018-9383
VL - 65
SP - 4155
EP - 4159
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
IS - 10
M1 - 8466017
ER -