ACS Nano,
Journal Year:
2024,
Volume and Issue:
18(35), P. 24076 - 24094
Published: Aug. 20, 2024
Resists
that
enable
high-throughput
and
high-resolution
patterning
are
essential
in
driving
the
semiconductor
technology
forward.
The
ultimate
performance
of
a
resist
lithography
is
limited
because
trade-off
between
resolution,
line-width
roughness,
sensitivity;
improving
one
or
two
these
parameters
typically
leads
to
loss
third.
As
patterned
feature
sizes
approach
angstrom
scale,
three
metrics
becomes
increasingly
hard
resolve
calls
for
fundamental
rethinking
chemistry.
Low-molecular-mass
monodispersed
metal-containing
resists
high
atom
economy
can
provide
not
only
very
resolution
but
also
low
roughness
without
sacrificing
sensitivity.
Here
we
describe
modular
platform
(molecular
mass
<500
Da)
where
molecular
consists
just
components:
metal
radical
initiator
bonded
it.
This
simple
system
amenable
electron
beam
(EBL)
extreme
ultraviolet
(EUVL)
unites
them
mechanistically,
giving
consolidated
perspective
chemical
processes
happening
during
exposure.
Irradiation
production
secondary
electrons
generate
radicals
metal.
brings
about
an
intramolecular
rearrangement
causes
solubility
switch
exposed
resist.
We
demonstrate
record
1.9–2.0
nm
isolated
patterns
7
half-pitch
dense
line-space
features
over
large
area
using
EBL.
With
EUVL,
12
shown
at
dose
68
mJ/cm2.
In
both
techniques,
was
found
be
≤2
nm,
value
any
platform,
leading
low-performance
metric,
Z
factor,
0.6
×
10–8
mJ·nm3.
by
instrumental
factors,
potential
level
unit
cell
envisaged,
making
low-molecular-mass
best
poised
angstrom-scale
lithography.
ChemPhotoChem,
Journal Year:
2022,
Volume and Issue:
6(11)
Published: June 27, 2022
Abstract
Photopolymerization
and
its
application
in
the
dental,
three‐dimensional
(3D)
printing,
coating
electronic
industry
has
become
increasingly
popular
over
last
decades.
A
huge
variety
of
photoinitiators
(PIs)
photoinitiating
systems
(PISs)
have
been
developed
that
are
able
to
generate
reactive
species,
e.
g.
radicals,
radical
cations,
cations
upon
light
absorption.
In
this
Review,
we
focus
on
radical‐generating
Type
I
PIs
which
undergo
homolytic
cleavage
after
irradiation
with
visible
light.
The
possibility
utilize
electromagnetic
above
400
nm
for
initiation
polymerization
reactions
provides
several
advantages
such
as
a
lower
energy
demand
higher
curing
depths
pigmented
systems.
Recent
developments
based
phosphorus
group
14
elements
well
other
selected
concepts
initiators
outlined
discussed
within
review.
Macromolecules,
Journal Year:
2022,
Volume and Issue:
55(7), P. 2475 - 2485
Published: March 30, 2022
A
series
of
50
oxime
esters
bearing
various
substituents
were
designed
and
synthesized
as
photoinitiators
(48
them
never
before
only
B1
B10
reported).
Good
light
absorption
properties
in
the
visible
range
observed
for
these
esters.
Some
structures
exhibited
better
photoinitiation
abilities
than
diphenyl(2,4,6-trimethylbenzoyl)phosphine
oxide
(TPO)
upon
exposure
to
a
LED@405
nm.
Interestingly,
PIs
with
methyl
substituent
on
ester
group
have
performance
others.
Substituent
effects
investigated
through
molecular
orbitals
calculations,
detection
CO2,
investigation
generated
free
radicals.
The
results
demonstrate
that
exert
major
ability
via
decarboxylation
reaction.
In
addition,
chemical
mechanism
was
proposed.
3D
printed
objects
successfully
obtained
by
using
most
reactive
photoinitiator,
their
thermal
initiation
behaviors
several
also
studied
(dual
thermal/photochemical
initiator
behavior).
Polymers,
Journal Year:
2023,
Volume and Issue:
15(2), P. 342 - 342
Published: Jan. 9, 2023
Currently,
increasing
attention
has
been
focused
on
light-emitting
diodes
(LEDs)-induced
photopolymerization.
The
common
LEDs
(e.g.,
LED
at
365
nm
and
405
nm)
possess
narrow
emission
bands.
Due
to
their
light
absorption
properties,
most
commercial
photoinitiators
are
sensitive
UV
cannot
be
optimally
activated
under
visible
irradiation.
Although
many
have
designed
for
LED-induced
free
radical
polymerization
cationic
polymerization,
there
is
still
the
issue
of
mating
between
LEDs.
Therefore,
development
novel
photoinitiators,
which
could
applied
irradiation,
significant.
Many
photoinitiating
systems
reported
in
past
decade.
In
this
review,
some
recently
developed
used
photopolymerization,
mainly
5
years,
summarized
categorized
as
Type
Ⅰ
Ⅱ
dye-based
systems.
addition,
properties
photoinitiation
efficiencies
discussed.
