"
In a breathtaking set of demonstrations, the authors show
the ability to integrate 20 nm FinFET devices onto thin flexible sheets of
plastic. They show the performance,
examine the bending properties, and argue for scalable use of the process in
applications of flexible electronics.
This work is at the very highest end of the distribution of research
papers in advanced materials, fabrication techniques, and unusual electronic
systems. I recommend publication, in the
most enthusiastic terms." – This is what Reviewer has written in his kind
review.
About what?
et al. has demonstrated the world’s highest
performance flexible electronics with the semiconductor industry’s most
advanced device architecture FinFET! In the paper entitled, “Flexible and
Transparent Silicon-on-Polymer Based Sub-20 nm Non-planar 3D FinFET for
Brain-architecture Inspired Computation”, we have demonstrated a pragmatic way to transform SOI based
state-of-the-art FinFET into flexible and semi-transparent silicon-on-polymer
FinFET while retaining high performance and integration density. The process
shown has the unique characteristic that all the devices can be fabricated
prior to release without any constraint set by the high thermal budget or by
the etch holes due to the extremely high etch selectivity between silicon and
silicon dioxide. Our process thus sets a major step towards the integration of
state-of-the-art high performance devices for ultra-mobile brain-inspired
foldable computers or ICs. The electrical superiority achieved with inorganic
semiconducting substrates and the maturity of silicon microfabrication industry
make the integration of silicon on flexible platforms the most logical next
step towards achieving high computational capabilities in mobile devices.
Ultra-thin (1 mm) nature of the silicon fabric with devices
makes it ultra-light-weight also. We have chosen to demonstrate high
performance P- and NMOS devices in flexible silicon fabric to prove the
compatibility of our process with the backbone of high performance CMOS based
electronics. Although we have not shown complete circuitry on flexible silicon
fabric due to mismatched Vth shift in PMOS devices, this work
indicates that with the correct process optimization and integration of dual
high-k/metal gate for threshold voltage correction, we can transform large
scale state-of-the-art high performance circuitry without affecting its
performance. The released transistors feature the most advanced architectures
used in semiconductor industry as well as the most sophisticated set of
materials, high-k/metal gate stack, used to overcome scaling problems in modern
solid state devices. Electrical characterization of our devices shows a
sub-threshold swing of 80 mVdec-1 for NMOS and 70 mVdec-1
for PMOS and Ion/Ioff ratio of 4.6 decades for NMOS and
4.78 decades for PMOS. The step sub-threshold swings indicate faster switching
with sufficient distinction between on and off state. The released fabric is 1
mm in thickness and is capable of achieving a minimum-bending radius of 5 mm in
device scale. Also, since the fabric is extremely thin and our host substrate
is a polyimide sheet, the complete set of devices exhibits semitransparency.
These fabricated devices show competitive electrical behavior and outstanding
bendability relying only on mature microfabrication processes. Finally, we
believe our process sets a major step towards the integration of the most
reliable and broadly used material in semiconductor industry, silicon, on
flexible platforms for the expansion of ultra-mobile high performance flexible
electronics which will mimic ultra-compact brain-inspired folding capability.
In our humble
opinion this is a feat we wanted to reach and now we go forward with more
inspirations and vigor in our hearts.
We have a KAUST
School student Rawan Ghanem publishing a paper in Adv. Mat.? Yes! Advanced Materials with a new
Impact Factor of 14.829, a 6.86% increase over 2011 (13.877) following
on from surges of 28% and 30% in the preceding two years. One key to the
success of Advanced Materials is its pronounced interdisciplinarity, manifested
in its rare listing in six different topic categories by ISI.
Way to go, Galo A.
Torres Sevilla, Jhonathan P. Rojas, Hossain M. Fahad, Aftab M. Hussain, Rawan
Ghanem, Casey E. Smith and Muhammad M. Hussain!!!