<s>
Magnetolithography	B-Algorithm
(	O
ML	O
)	O
is	O
a	O
photoresist-less	O
and	O
photomaskless	B-Algorithm
lithography	I-Algorithm
method	O
for	O
patterning	O
wafer	B-Architecture
surfaces	O
.	O
</s>
<s>
ML	O
based	O
on	O
applying	O
a	O
magnetic	O
field	O
on	O
the	O
substrate	B-Architecture
using	O
paramagnetic	O
metal	O
masks	O
named	O
"	O
magnetic	O
mask	O
"	O
placed	O
on	O
either	O
topside	O
or	O
backside	O
of	O
the	O
wafer	B-Architecture
.	O
</s>
<s>
Magnetic	O
masks	O
are	O
analogous	O
to	O
a	O
photomask	B-Algorithm
in	O
photolithography	O
,	O
in	O
that	O
they	O
define	O
the	O
spatial	O
distribution	O
and	O
shape	O
of	O
the	O
applied	O
magnetic	O
field	O
.	O
</s>
<s>
cobalt	B-Algorithm
nanoparticles	O
)	O
that	O
are	O
assembled	O
over	O
the	O
substrate	B-Architecture
according	O
to	O
the	O
field	O
induced	O
by	O
the	O
mask	O
which	O
blocks	O
its	O
areas	O
from	O
reach	O
of	O
etchants	O
or	O
depositing	O
materials	O
(	O
e.g.	O
</s>
<s>
In	O
the	O
positive	O
approach	O
,	O
the	O
magnetic	O
nanoparticles	O
react	O
chemically	O
or	O
interact	O
via	O
chemical	O
recognition	O
with	O
the	O
substrate	B-Architecture
.	O
</s>
<s>
Hence	O
,	O
the	O
magnetic	O
nanoparticles	O
are	O
immobilized	O
at	O
selected	O
locations	O
,	O
where	O
the	O
mask	O
induces	O
a	O
magnetic	O
field	O
,	O
resulting	O
in	O
a	O
patterned	O
substrate	B-Architecture
.	O
</s>
<s>
In	O
the	O
negative	O
approach	O
,	O
the	O
magnetic	O
nanoparticles	O
are	O
inert	O
to	O
the	O
substrate	B-Architecture
.	O
</s>
<s>
Hence	O
,	O
once	O
they	O
pattern	O
the	O
substrate	B-Architecture
,	O
they	O
block	O
their	O
binding	O
site	O
on	O
the	O
substrate	B-Architecture
from	O
reacting	O
with	O
another	O
reacting	O
agent	O
.	O
</s>
<s>
After	O
the	O
adsorption	O
of	O
the	O
reacting	O
agent	O
,	O
the	O
nanoparticles	O
are	O
removed	O
,	O
resulting	O
in	O
a	O
negatively	O
patterned	O
substrate	B-Architecture
.	O
</s>
