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@ -65,3 +65,48 @@
year = {2011}
}
@article{graphene-review-2010,
abstract = {Graphene has changed from being the exclusive domain of condensed-matter physicists to being explored by those in the electron-device community. In particular, graphene-based transistors have developed rapidly and are now considered an option for post-silicon electronics. However, many details about the potential performance of graphene transistors in real applications remain unclear. Here I review the properties of graphene that are relevant to electron devices, discuss the trade-offs among these properties and examine their effects on the performance of graphene transistors in both logic and radiofrequency applications. I conclude that the excellent mobility of graphene may not, as is often assumed, be its most compelling feature from a device perspective. Rather, it may be the possibility of making devices with channels that are extremely thin that will allow graphene field-effect transistors to be scaled to shorter channel lengths and higher speeds without encountering the adverse short-channel effects that restrict the performance of existing devices. Outstanding challenges for graphene transistors include opening a sizeable and well-defined bandgap in graphene, making large-area graphene transistors that operate in the current-saturation regime and fabricating graphene nanoribbons with well-defined widths and clean edges.},
author = {Schwierz, Frank},
doi = {10.1038/nnano.2010.89},
issn = {1748-3395},
journal = {Nature Nanotechnology},
number = {7},
pages = {487--496},
risfield_0_da = {2010/07/01},
title = {Graphene transistors},
url = {https://www.nature.com/articles/nnano.2010.89},
urldate = {2021-04-25},
volume = {5},
year = {2010}
}
@misc{warda-gfet-review,
archiveprefix = {arXiv},
author = {Warda, Mohamed},
eprint = {2010.10382},
primaryclass = {cond-mat.mes-hall},
title = {Graphene Field Effect Transistors: A Review},
url = {https://arxiv.org/abs/2010.10382},
urldate = {2021-04-25},
year = {2020}
}
@article{owidtechnologicalprogress,
author = {Roser, Max and Ritchie, Hannah},
journal = {Our World in Data},
title = {Technological Progress},
url = {https://ourworldindata.org/technological-progress},
urldate = {2021-04-25},
year = {2013}
}
@misc{transistors-21,
author = {Courtland, Rachel},
organization = {IEEE Spectrum},
title = {Transistors Could Stop Shrinking in 2021},
url = {https://spectrum.ieee.org/semiconductors/devices/transistors-could-stop-shrinking-in-2021},
urldate = {2021-04-25},
year = {2016}
}

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@ -273,7 +273,9 @@ Introduction
\end_layout
\begin_layout Standard
Graphene is a 2D allotrope of carbon with
Graphene is a 2D allotrope of carbon with highly interesting mechanical
and electrical properties that have made it a target of significant research
in the last two decades since it's experimental discovery in 2004.
\end_layout
\begin_layout Standard
@ -288,8 +290,8 @@ noprefix "false"
\end_inset
presents two applications of graphene that take advantage of it's behaviour
at high frequencies.
presents two applications of graphene that take advantage of it's electrical
and mechanical behaviour at high frequencies.
Section
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@ -312,10 +314,259 @@ name "sec:Applications"
\end_inset
\end_layout
\begin_layout Standard
This section explores two uses of graphene for high frequency applications.
First, the applicability of graphene for field effect transisitors will
be considered as a channel material.
Throughout, a particular focus will be paid to use in digital logic and
thus as a possible replacement for the current Silicon CMOS/MOSFET paradigm.
\end_layout
\begin_layout Standard
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second application
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\begin_layout Subsection
Graphene Transistors
Digital Logic
\end_layout
\begin_layout Standard
Silicon-based CMOS/MOSFET digital logic is the basis on which much of the
modern electronics landscape has been built.
From intergrated logic circuits to CPUs, it is hard to overstate how important
this technology has proven to be.
The need for more powerful devices has increased pressure for smaller and
more efficient transistors, such that more can fit into a single device.
This progress is typically described by Moore's Law and can be seen graphically
in figure
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.
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The number of transistors in commercial CPUs between 1970 and 2020
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However, as transistors are made smaller, theoretical limits for many limiting
factors are approached.
In 2015, the ITRS predicted that by 2021 the current push for smaller transisto
rs would no longer be economically viable, instead requiring innovative
3D device structures
\begin_inset CommandInset citation
LatexCommand cite
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\end_inset
.
Some of the most important limiting factors in the current Silicon landscape
are short-channel effects, a group of undesirable electrical properties
that can occur when the channel length of a MOSFET device is of the same
order of magnitude as the depletion layer
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cite
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.
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Limitations of silicon
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Terahertz switching
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Electron mobility
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Thermal conductivity
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Sensitivity
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2D channel
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Short channel effects
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Hard to turn off, low on-off I multiplier (bandgap stuff)
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Need to introduce a bandgap which decimates mobility
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Hard to fabricate, delamination and stuff
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@ -498,8 +749,17 @@ noprefix "false"
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.
Similarly to the original, the magnitude of the function can be seen to
be between 48 and 63 mS for TTF and CoCp
Similarly to the original, the magnitude (figure
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) of the function can be seen to be between 48 and 63 mS for TTF and CoCp
\begin_inset script subscript
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@ -527,10 +787,20 @@ noprefix "false"
the magnitude tends closer to the imaginary component than the real.
Beyond 100 THz, the imaginary component dips below zero, with a trough
of -0.5 mS around 250 THz.
Looking to the phase information, before 10 GHz the phase can be seen to
be 0, however as the imaginary component begins to peak, the phase increases
to a max of 90 degrees, continuing until 100 THz where the negative imaginary
peak causes the phase to sharply drop to -90 degrees.
Looking to the phase information (figure
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), before 10 GHz the phase can be seen to be 0, however as the imaginary
component begins to peak, the phase increases to a max of 90 degrees, continuin
g until 100 THz where the negative imaginary peak causes the phase to sharply
drop to -90 degrees.
There is little difference between the two dopants, they are equal until
100 THz where the TTF shows a -100 THz offset from the CoCp
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@ -765,7 +1074,30 @@ status open
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Complex conductivity magnitude and phase for TTF and CoCp
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Complex conductivity magnitude (a) and phase (b) for TTF and CoCp
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Intraband and interband conductivity for TTF and CoCp
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Intraband (a) and interband (b) conductivity for TTF and CoCp
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@ -1199,6 +1601,37 @@ status open
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@ -1259,7 +1715,7 @@ The conductivity can broadly be seen to follow the same spectral profile
over the range of carrier concentrations as can be seen in figure
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reference "fig:david-simulation-conductivity"
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@ -1857,7 +2313,7 @@ m
figure
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@ -1955,8 +2450,31 @@ status open
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Inter- and intraband conductivity for high and low carrier concentration
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Intraband (a) and interband (b) conductivity for high and low carrier concentrat
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Inter- and intraband conductivity for low, room and high temperature graphene
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Intraband (a) and interband (b) conductivity for low, room and high temperature
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Inter- and intraband conductivity with 3 different scattering times for
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Intraband (a) and interband (b) conductivity with 3 different scattering
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@ -3155,6 +3859,32 @@ From the presented trends for how conductivity is affected by a varied carrier
lifetime.
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Equation analysis
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Why?
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\begin_layout Section
Conclusion
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