Page 17 - IOE_Winter 24

AMORPHOUS

SILICON CARBIDE: A

BREAKTHROUGH FOR

MICROCHIPS

Scientists at Delft University of Technology methodologies. The material can also be
have succeeded in creating amorphous silicon produced in large quantities, unlike diamond or
carbide , or a-SiC, the yield strength of which graphene.
surpasses that of conventional materials such
Leader of the research, Assistant Professor Richard
as Kevlar, making it ideal for applications like
Norte, states:
ultra-sensitive microchip sensors, advanced
solar cells, innovative space exploration “ In terms of emerging fields, there are several
technologies and DNA sequencing. emerging fields that require nanoscale
elements that can withstand large forces that
SThe tensile strength of amorphous silicon
create tensile forces in suspended materials.
carbide is around 10GigaPascal, which is
For instance, there are now interstellar space
especially useful in sensor applications where
missions like Starshot Breakthrough, which
high strength materials allow for higher tensile
require ultra-strong very thin reflectors as
forces in vibrating elements that can now be
sails that are accelerated to a fifth of the
made on a microchip. These higher tensile forces
speed of light with high-powered lasers. This is
allow the vibrating elements to be increasingly
something our lab is currently working on.
more sensitive sensors.
Mechanically, this material performs extremely
Unlike traditional crystalline materials such as
well, so for nanomechanical technologies it is
diamonds, a-SiC has an amorphous structure,
very interesting. Optically, our initial experiments
meaning that its atoms are arranged in a
show that its optical properties are not great. By
random, disorganised pattern, but this lack of
this I mean that its optical absorption is high. This
uniform atomic arrangement is actually found to
can lead to heating and optical losses which are
contribute significantly to the material’s overall
usually not preferred. We would like to improve
strength, in contrast to conventional materials
this optical absorption by changing the chemistry
science theory.
so that we can use this material for optical
The team at Delft tested the tensile strength of microcircuits. This would really open up its uses in
a-SiC using nanostrings to induce high tensile nanophotonics and even interstellar missions”.
forces. This nanostrings approach, where the
[ Reference: Miles, S., Electronic Specifier, 13th.
use of extremely thin nano-scale strings or
November 2023 ]
wires are integrated into microchip architecture,
represents a major advance in material testing
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