Atomic force microscopy image of a glycopolymer nano-organized into sugar cylinders in a silicon containing polystyrene matrix. Image: CERMAV (CNRS) |
The
development of a new combination of polymers associating sugars with
oil-based macromolecules makes it possible to design ultra-thin films
capable of self-organization with a 5-nm resolution. This could open up
new horizons for increasing the capacity of hard disks and the speed of
microprocessors.
The
result of a French-American collaboration spearheaded by the Centre de
Recherches sur les Macromolécules Végétales (CNRS), this work has led to
the filing of two patents. It is published in the journal ACS Nano.
This new class of thin films based on hybrid copolymers could give rise
to numerous applications in flexible electronics, in areas as diverse as
nanolithography, biosensors and photovoltaic cells.
Before
new generations of microprocessors can be devised, an evolution in
lithography, the technique used for printing electronic circuits, is
indispensable. Until now, the thin films used in electronic circuits
have been designed from synthetic polymers exclusively derived from
petroleum. However, these thin films have limitations: their minimum
structural resolution is around 20 nanometers and cannot be reduced
further by combining petroleum-derived polymers. This limit has been one
of the main obstacles to the development of new generations of
very-high-resolution flexible electronic devices.
Why
was there such a limit? Because of the low incompatibility between the
two blocks of polymers, both derived from oil. For that reason, the team
headed by Redouane Borsali, CNRS senior researcher at the Centre de
Recherches sur les Macromolécules Végétales (CERMAV), came up with a
hybrid material: this new class of thin films combines sugar-based and
petroleum-derived (silicon containing polystyrene) polymers with widely
different physical/chemical characteristics. This copolymer(1), formed
of highly incompatible elementary building blocks, is similar to an oil
bubble attached to a small water bubble. The researchers have shown that
this type of structure is capable of organizing itself into sugar
cylinders within a petroleum-based polymer lattice, each structure
having a size of 5 nm, i.e. much smaller than the resolution of “old”
copolymers, exclusively composed of petroleum derivatives. In addition,
this new generation of material is made from an abundant, renewable and
biodegradable resource: sugar.
Achieving
this performance makes it possible to envisage numerous applications in
flexible electronics: miniaturization of circuit lithography, six-fold
increase in information storage capacity (flash memories—USB keys—no
longer limited to 1 Tbit of data but 6 Tbit), enhanced performance of
photovoltaic cells, biosensors, etc. The researchers are now seeking to
improve control of these nano-glycofilms’ large-scale organization and
design in different self-organized structures.
Source: CNRS
