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Thanasis Georgiou,
Rashid Jalil, Branson D Belle,
Liam Britnell,
Roman V Gorbachev,
Sergey V Morozov,
Yong-Jin Kim,
Ali Gholinia,
Sarah J Haigh,
Oleg Makarovsky,
Laurence Eaves,
Leonid A Ponomarenko,
Andre K Geim,
Kostya S Novoselov,
Artem Mishchenko
[show abstract]
[hide abstract]
ABSTRACT: The celebrated electronic properties of graphene have opened the way for materials just one atom thick to be used in the post-silicon electronic era. An important milestone was the creation of heterostructures based on graphene and other two-dimensional crystals, which can be assembled into three-dimensional stacks with atomic layer precision. Such layered structures have already demonstrated a range of fascinating physical phenomena, and have also been used in demonstrating a prototype field-effect tunnelling transistor, which is regarded to be a candidate for post-CMOS (complementary metal-oxide semiconductor) technology. The range of possible materials that could be incorporated into such stacks is very large. Indeed, there are many other materials with layers linked by weak van der Waals forces that can be exfoliated and combined together to create novel highly tailored heterostructures. Here, we describe a new generation of field-effect vertical tunnelling transistors where two-dimensional tungsten disulphide serves as an atomically thin barrier between two layers of either mechanically exfoliated or chemical vapour deposition-grown graphene. The combination of tunnelling (under the barrier) and thermionic (over the barrier) transport allows for unprecedented current modulation exceeding 1 × 10(6) at room temperature and very high ON current. These devices can also operate on transparent and flexible substrates.
Nature Nanotechnology 12/2012; · 27.27 Impact Factor
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Thanasis Georgiou,
Rashid Jalil, Branson D. Belle,
Liam Britnell,
Roman V. Gorbachev,
Sergey V. Morozov,
Yong-Jin Kim,
Ali Gholinia,
Sarah J. Haigh,
Oleg Makarovsky,
Laurence Eaves,
Leonid A. Ponomarenko,
Andre K. Geim,
Kostya S. Novoselov,
Artem Mishchenko
[show abstract]
[hide abstract]
ABSTRACT: The celebrated electronic properties of graphene have opened way for
materials just one-atom-thick to be used in the post-silicon electronic era. An
important milestone was the creation of heterostructures based on graphene and
other two-dimensional (2D) crystals, which can be assembled in 3D stacks with
atomic layer precision. These layered structures have already led to a range of
fascinating physical phenomena, and also have been used in demonstrating a
prototype field effect tunnelling transistor - a candidate for post-CMOS
technology. The range of possible materials which could be incorporated into
such stacks is very large. Indeed, there are many other materials where layers
are linked by weak van der Waals forces, which can be exfoliated and combined
together to create novel highly-tailored heterostructures. Here we describe a
new generation of field effect vertical tunnelling transistors where 2D
tungsten disulphide serves as an atomically thin barrier between two layers of
either mechanically exfoliated or CVD-grown graphene. Our devices have
unprecedented current modulation exceeding one million at room temperature and
can also operate on transparent and flexible substrates.
11/2012;
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Liam Britnell,
Roman V Gorbachev,
Rashid Jalil, Branson D Belle,
Fred Schedin,
Mikhail I Katsnelson,
Laurence Eaves,
Sergey V Morozov,
Alexander S Mayorov,
Nuno M R Peres,
Antonio H Castro Neto,
Jon Leist,
Andre K Geim,
Leonid A Ponomarenko,
Kostya S Novoselov
[show abstract]
[hide abstract]
ABSTRACT: We investigate the electronic properties of ultrathin hexagonal boron nitride (h-BN) crystalline layers with different conducting materials (graphite, graphene, and gold) on either side of the barrier layer. The tunnel current depends exponentially on the number of h-BN atomic layers, down to a monolayer thickness. Conductive atomic force microscopy scans across h-BN terraces of different thickness reveal a high level of uniformity in the tunnel current. Our results demonstrate that atomically thin h-BN acts as a defect-free dielectric with a high breakdown field. It offers great potential for applications in tunnel devices and in field-effect transistors with a high carrier density in the conducting channel.
Nano Letters 03/2012; 12(3):1707-10. · 13.20 Impact Factor
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Liam Britnell,
Roman V. Gorbachev,
Rashid Jalil, Branson D. Belle,
Fred Schedin,
Mikhail I. Katsnelson,
Laurence Eaves,
Sergey V. Morozov,
Alexander S. Mayorov,
Nuno M. R. Peres,
Antonio H. Castro Neto,
Jon Leist,
Andre K. Geim,
Leonid A. Ponomarenko,
Kostya S. Novoselov
[show abstract]
[hide abstract]
ABSTRACT: We investigate the electronic properties of heterostructures based on
ultrathin hexagonal boron nitride (h-BN) crystalline layers sandwiched between
two layers of graphene as well as other conducting materials (graphite, gold).
The tunnel conductance depends exponentially on the number of h-BN atomic
layers, down to a monolayer thickness. Exponential behaviour of I-V
characteristics for graphene/BN/graphene and graphite/BN/graphite devices is
determined mainly by the changes in the density of states with bias voltage in
the electrodes. Conductive atomic force microscopy scans across h-BN terraces
of different thickness reveal a high level of uniformity in the tunnel current.
Our results demonstrate that atomically thin h-BN acts as a defect-free
dielectric with a high breakdown field; it offers great potential for
applications in tunnel devices and in field-effect transistors with a high
carrier density in the conducting channel.
02/2012;
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Roman V Gorbachev,
Ibtsam Riaz,
Rahul R Nair,
Rashid Jalil,
Liam Britnell, Branson D Belle,
Ernie W Hill,
Kostya S Novoselov,
Kenji Watanabe,
Takashi Taniguchi,
Andre K Geim,
Peter Blake
Small 02/2011; 7(4):465-8. · 8.35 Impact Factor
