<s>
Local	B-Algorithm
oxidation	I-Algorithm
nanolithography	I-Algorithm
(	O
LON	O
)	O
is	O
a	O
tip-based	O
nanofabrication	B-Algorithm
method	O
.	O
</s>
<s>
It	O
is	O
based	O
on	O
the	O
spatial	O
confinement	O
on	O
an	O
oxidation	B-Operating_System
reaction	O
under	O
the	O
sharp	O
tip	O
of	O
an	O
atomic	O
force	O
microscope	O
.	O
</s>
<s>
The	O
local	O
oxidation	B-Operating_System
of	O
a	O
surface	O
by	O
means	O
of	O
a	O
scanning	O
probe	O
technique	O
was	O
first	O
observed	O
by	O
Dagata	O
and	O
co-workers	O
in	O
1990	O
who	O
locally	O
modified	O
a	O
hydrogen-terminated	O
silicon	O
surface	O
into	O
silicon	O
dioxide	O
by	O
applying	O
a	O
bias	O
voltage	O
between	O
the	O
tip	O
of	O
a	O
scanning	O
tunneling	O
microscope	O
and	O
the	O
surface	O
itself	O
.	O
</s>
<s>
In	O
1993	O
Day	O
and	O
Allee	O
demonstrated	O
the	O
possibility	O
of	O
performing	O
local	O
oxidation	B-Operating_System
experiments	O
with	O
an	O
atomic	O
force	O
microscope	O
,	O
which	O
opened	O
the	O
way	O
to	O
applying	O
the	O
technique	O
to	O
a	O
large	O
variety	O
of	O
materials	O
.	O
</s>
<s>
Currently	O
,	O
local	O
oxidation	B-Operating_System
experiments	O
are	O
performed	O
with	O
an	O
atomic	O
force	O
microscope	O
operated	O
in	O
contact	O
or	O
noncontact	O
mode	O
with	O
additional	O
circuits	O
to	O
apply	O
voltage	O
pulses	O
between	O
tip	O
and	O
sample	O
.	O
</s>
<s>
The	O
local	O
oxidation	B-Operating_System
process	O
is	O
mediated	O
by	O
the	O
formation	O
of	O
a	O
water	O
meniscus	O
.	O
</s>
<s>
In	O
order	O
to	O
perform	O
Local	B-Algorithm
Oxidation	I-Algorithm
Nanolithography	I-Algorithm
,	O
the	O
relative	O
humidity	O
in	O
the	O
AFM	O
chamber	O
is	O
kept	O
between	O
30%	O
and	O
60%	O
.	O
</s>
<s>
When	O
the	O
liquid	O
meniscus	O
is	O
created	O
the	O
applied	O
voltage	O
pulse	O
causes	O
an	O
oxidation	B-Operating_System
reaction	O
by	O
breaking	O
the	O
covalent	O
bonds	O
in	O
the	O
water	O
molecules	O
.	O
</s>
<s>
The	O
chemical	O
reactions	O
that	O
govern	O
the	O
Local	O
Oxidation	B-Operating_System
in	O
a	O
metallic	O
substrate	B-Architecture
(	O
M	O
)	O
are	O
the	O
following	O
:	O
</s>
<s>
Finally	O
the	O
AFM	O
continues	O
to	O
scan	O
the	O
sample	O
thus	O
allowing	O
to	O
image	O
MOn	O
nanostructure	O
fabricated	O
during	O
the	O
Local	O
Oxidation	B-Operating_System
process	O
with	O
the	O
very	O
same	O
tip	O
used	O
for	O
its	O
fabrication	O
.	O
</s>
<s>
Local	O
oxidation	B-Operating_System
experiments	O
can	O
be	O
performed	O
with	O
almost	O
any	O
kind	O
of	O
atomic	O
force	O
microscope	O
.	O
</s>
<s>
The	O
development	O
of	O
nanometer-scale	O
lithographies	B-Algorithm
is	O
the	O
focus	O
of	O
an	O
intense	O
research	O
activity	O
because	O
progress	O
on	O
nanotechnology	O
depends	O
on	O
the	O
capability	O
to	O
fabricate	O
,	O
position	O
and	O
interconnect	O
nanometer-scale	O
structures	O
.	O
</s>
<s>
Local	B-Algorithm
Oxidation	I-Algorithm
Nanolithography	I-Algorithm
allows	O
to	O
create	O
a	O
large	O
variety	O
of	O
motives	O
like	O
dots	O
,	O
lines	O
and	O
letters	O
with	O
nanometer	O
accuracy	O
.	O
</s>
<s>
This	O
pattern	O
versatility	O
can	O
be	O
used	O
for	O
information	B-General_Concept
storage	I-General_Concept
or	O
to	O
design	O
etch-resistant	O
nanomasks	B-Algorithm
in	O
order	O
to	O
fabricate	O
nanodevices	B-Algorithm
as	O
well	O
as	O
many	O
other	O
applications	O
.	O
</s>
<s>
It	O
is	O
possible	O
to	O
store	O
information	O
using	O
dot-like	O
nanostructures	O
created	O
by	O
the	O
local	O
oxidation	B-Operating_System
of	O
a	O
surface	O
.	O
</s>
<s>
demonstrated	O
that	O
this	O
methods	O
allows	O
to	O
obtain	O
an	O
information	B-Device
density	I-Device
of	O
1.6	O
Tbit/in2	O
.	O
</s>
<s>
However	O
,	O
only	O
read-only	B-Device
memories	I-Device
can	O
be	O
fabricated	O
with	O
this	O
technique	O
.	O
</s>
<s>
Local	O
oxidation	B-Operating_System
of	O
silicon	O
surfaces	O
by	O
noncontact	O
atomic-force	O
microscopy	O
is	O
an	O
emerging	O
and	O
promising	O
method	O
for	O
patterning	O
surfaces	O
at	O
the	O
nanometer	O
scale	O
due	O
to	O
its	O
very	O
precise	O
control	O
of	O
the	O
feature	O
size	O
.	O
</s>
<s>
This	O
method	O
of	O
nanopositioning	O
is	O
an	O
important	O
tool	O
for	O
the	O
fabrication	O
of	O
new	O
nanodevices	B-Algorithm
based	O
on	O
the	O
novel	O
properties	O
exhibited	O
by	O
some	O
nanoparticles	O
and	O
molecules	O
.	O
</s>
<s>
Potential	O
applications	O
of	O
single-molecule	O
magnets	O
(	O
SMMs	O
)	O
such	O
as	O
Mn12	O
as	O
bits	O
for	O
information	B-General_Concept
storage	I-General_Concept
or	O
qubits	O
for	O
quantum	B-Architecture
computation	I-Architecture
require	O
methods	O
for	O
nanoscale-controlled	O
positioning	O
and/or	O
manipulation	O
of	O
those	O
molecules	O
.	O
</s>
<s>
By	O
using	O
local	B-Algorithm
oxidation	I-Algorithm
nanolithography	I-Algorithm
as	O
tool	O
for	O
the	O
fabrication	O
of	O
etch-resistant	O
nanomasks	B-Algorithm
,	O
it	O
is	O
possible	O
to	O
fabricate	O
nanoscale	O
electronic	O
devices	O
,	O
such	O
as	O
field-effect	O
transistors	O
,	O
single-electron	B-Algorithm
transistors	I-Algorithm
,	O
Josephson	O
junctions	O
,	O
quantum	O
rings	O
or	O
SQUIDs	B-Protocol
.	O
</s>
<s>
LON	O
also	O
allows	O
to	O
fabricate	O
Silicon	B-Algorithm
Nanowires	I-Algorithm
(	O
SiNWs	B-Algorithm
)	O
in	O
a	O
top-down	O
fashion	O
starting	O
from	O
silicon	B-Algorithm
on	I-Algorithm
insulator	I-Algorithm
(	O
SOI	O
)	O
wafers	B-Architecture
.	O
</s>
<s>
Local	B-Algorithm
oxidation	I-Algorithm
nanolithography	I-Algorithm
contributes	O
to	O
the	O
nanometric	O
precision	O
of	O
the	O
device	O
fabrication	O
.	O
</s>
<s>
This	O
top-down	O
fabrication	O
technique	O
allows	O
the	O
fabrication	O
of	O
a	O
large	O
variety	O
of	O
SiNWs	B-Algorithm
with	O
different	O
shapes	O
,	O
from	O
angular	O
to	O
circular	O
.	O
</s>
<s>
It	O
also	O
allows	O
the	O
precise	O
positioning	O
of	O
the	O
silicon	B-Algorithm
nanowires	I-Algorithm
in	O
any	O
desired	O
position	O
,	O
making	O
easier	O
its	O
integration	O
;	O
indeed	O
,	O
this	O
technique	O
is	O
compatible	O
with	O
the	O
standard	O
silicon	O
CMOS	B-Device
processing	O
technology	O
.	O
</s>
<s>
Single	O
crystalline	O
silicon	B-Algorithm
nanowires	I-Algorithm
have	O
already	O
shown	O
a	O
great	O
potential	O
as	O
ultrasensitive	O
sensors	O
by	O
detecting	O
changes	O
in	O
the	O
nanowire	O
conductivity	O
when	O
a	O
specific	O
analyte	O
is	O
present	O
.	O
</s>
<s>
Local	B-Algorithm
oxidation	I-Algorithm
nanolithography	I-Algorithm
,	O
therefore	O
,	O
is	O
a	O
promising	O
technique	O
to	O
allow	O
the	O
realisation	O
of	O
array	O
of	O
biosensors	O
.	O
</s>
