F R O N T I E R
“The world’s lightest and thinnest flexible integrated circuits will
produce stress-free wearable healthcare sensors”
Technology the knack
of so arranging the
world that we don’t
have to experience
it
An 'imperceptible' electronic skin that can
monitor the body, or help people to
communicate through touch, is now possible
thanks to a new ultra-light and flexible sensor
foil.
An Insight on the newer technology
Background
Sensors and electronic circuits for healthcare and medical applications
are generally fabricated using silicon and other rigid electronic
materials. To minimize the discomfort of wearing rigid sensors, it is
highly desirable to use soft electronic materials particularly for
devices that come directly into contact with the skin. In this regard,
electronics manufactured on thin polymeric films are very attractive.
In general, a thinner substrate will provide better mechanical
flexibility. However, directly manufacturing sensors or electronic
circuits on ultrathin polymeric films with thicknesses of several
micrometers or less is a difficult task if conventional semiconductor
processes are used. It was widely believed that 10 µm represented the
minimum possible thickness of the substrate and that any further
reduction in the thickness was almost impossible.
Thus far, electronics and IT devices have relied
on rigid materials, mainly silicon, which have
formed the basis of healthcare and medical
sensors and electronic circuits. To realize
next-generation electronics that harmonize
technology with humankind, it is highly
desirable to replace these rigid electronic
components with soft materials, particularly for
device parts that are placed directly on the skin.
For this reason, it is important to develop a
manufacturing technology that can fabricate
soft organic transistor ICs on ultrathin flexible
polymeric films thick.
What is Imperceptible Electronics ?
The International research team has manufactured the world
thinnest and lightest soft organic transistor integrated circuits
(ICs) on ultrathin polymeric films with a thickness of only
1.2 µm. This was possible because the team developed a
novel technique to form a high-quality 19-nm-thick (one
nanometer (nm) is 1/1,000,000,000 of a meter) insulating
layer on the rough surface of the 1.2-µm-thick polymeric
film.
Feather
The work is the brainchild of Tokyo University
scientist Martin Kaltenbrunner and his colleagues who
used relatively standard techniques to construct the
devices.
Imperceptible Electronics is
lighter than a feather
The organic transistor ICs exhibit extraordinary robustness in
spite of being super-thin. Indeed, the electrical properties and
mechanical performance of the transistor ICs were
practically unchanged (no degradation was seen) even
when squeezed to a bending radius of 5 µm, dipped in
physiological saline, or stretched up to double their original
size. These organic transistor ICs have been utilized to
develop a flexible touch sensor system prototype.
Imperceptible electronics, namely, extremely thin,
lightweight electronics whose presence cannot be perceived.
Nvidia's new five-core mobile processor is a beast, with 72 GPU cores and roughly six times the speed of its predecessor, is
no surprise. It has an integrated 4G LTE modem and can take high dynamic range (HDR) photos as much as 10 times
faster than the i-Phone.
THE ELECTRONICLE XV
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