TY - JOUR
T1 - Carrier Polarity Control in α-MoTe2 Schottky Junctions Based on Weak Fermi-Level Pinning
AU - Nakaharai, Shu
AU - Yamamoto, Mahito
AU - Ueno, Keiji
AU - Tsukagoshi, Kazuhito
N1 - Funding Information:
This work was supported by JSPS KAKENHI Grant Nos. 15K06006 and 25107004.
Publisher Copyright:
© 2016 American Chemical Society.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 2016/6/15
Y1 - 2016/6/15
N2 - The polarity of the charge carriers injected through Schottky junctions of α-phase molybdenum ditelluride (α-MoTe2) and various metals was characterized. We found that the Fermi-level pinning in the metal/α-MoTe2 Schottky junction is so weak that the polarity of the carriers (electron or hole) injected from the junction can be controlled by the work function of the metals, in contrast to other transition metal dichalcogenides such as MoS2. From the estimation of the Schottky barrier heights, we obtained p-type carrier (hole) injection from a Pt/α-MoTe2 junction with a Schottky barrier height of 40 meV at the valence band edge. n-Type carrier (electron) injection from Ti/α-MoTe2 and Ni/α-MoTe2 junctions was also observed with Schottky barrier heights of 50 and 100 meV, respectively, at the conduction band edge. In addition, enhanced ambipolarity was demonstrated in a Pt-Ti hybrid contact with a unique structure specially designed for polarity-reversible transistors, in which Pt and Ti electrodes were placed in parallel for injecting both electrons and holes.
AB - The polarity of the charge carriers injected through Schottky junctions of α-phase molybdenum ditelluride (α-MoTe2) and various metals was characterized. We found that the Fermi-level pinning in the metal/α-MoTe2 Schottky junction is so weak that the polarity of the carriers (electron or hole) injected from the junction can be controlled by the work function of the metals, in contrast to other transition metal dichalcogenides such as MoS2. From the estimation of the Schottky barrier heights, we obtained p-type carrier (hole) injection from a Pt/α-MoTe2 junction with a Schottky barrier height of 40 meV at the valence band edge. n-Type carrier (electron) injection from Ti/α-MoTe2 and Ni/α-MoTe2 junctions was also observed with Schottky barrier heights of 50 and 100 meV, respectively, at the conduction band edge. In addition, enhanced ambipolarity was demonstrated in a Pt-Ti hybrid contact with a unique structure specially designed for polarity-reversible transistors, in which Pt and Ti electrodes were placed in parallel for injecting both electrons and holes.
KW - Fermi-level pinning
KW - Schottky junction
KW - carrier injection
KW - field-effect transistor
KW - transition metal dichalcogenide
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U2 - 10.1021/acsami.6b02036
DO - 10.1021/acsami.6b02036
M3 - Article
AN - SCOPUS:84975299230
SN - 1944-8244
VL - 8
SP - 14732
EP - 14739
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
IS - 23
ER -