<s>
For	O
some	O
difficult	O
materials	O
(	O
such	O
as	O
magnetic	O
materials	O
)	O
,	O
the	O
volatility	O
can	O
only	O
be	O
obtained	O
when	O
the	O
wafer	B-Architecture
temperature	O
is	O
increased	O
.	O
</s>
<s>
A	O
plasma	B-Algorithm
etcher	I-Algorithm
,	O
or	O
etching	O
tool	O
,	O
is	O
a	O
tool	O
used	O
in	O
the	O
production	O
of	O
semiconductor	O
devices	O
.	O
</s>
<s>
A	O
plasma	B-Algorithm
etcher	I-Algorithm
produces	O
a	O
plasma	O
from	O
a	O
process	O
gas	O
,	O
typically	O
oxygen	O
or	O
a	O
fluorine-bearing	O
gas	O
,	O
using	O
a	O
high	O
frequency	O
electric	O
field	O
,	O
typically	O
13.56	B-Algorithm
MHz	I-Algorithm
.	O
</s>
<s>
A	O
silicon	B-Architecture
wafer	I-Architecture
is	O
placed	O
in	O
the	O
plasma	B-Algorithm
etcher	I-Algorithm
,	O
and	O
the	O
air	O
is	O
evacuated	O
from	O
the	O
process	O
chamber	O
using	O
a	O
system	O
of	O
vacuum	O
pumps	O
.	O
</s>
<s>
Industrial	O
plasma	B-Algorithm
etchers	I-Algorithm
often	O
feature	O
plasma	O
confinement	O
to	O
enable	O
repeatable	O
etch	O
rates	O
and	O
precise	O
spatial	O
distributions	O
in	O
plasmas	O
.	O
</s>
<s>
For	O
example	O
,	O
plasma	O
etching	O
can	O
be	O
used	O
to	O
create	O
deep	O
trenches	O
on	O
the	O
surface	O
of	O
silicon	O
for	O
uses	O
in	O
microelectromechanical	B-Architecture
systems	I-Architecture
.	O
</s>
<s>
Plasma	O
can	O
be	O
used	O
to	O
grow	O
a	O
silicon	O
dioxide	O
film	O
on	O
a	O
silicon	B-Architecture
wafer	I-Architecture
(	O
using	O
an	O
oxygen	O
plasma	O
)	O
,	O
or	O
can	O
be	O
used	O
to	O
remove	O
silicon	O
dioxide	O
by	O
using	O
a	O
fluorine	O
bearing	O
gas	O
.	O
</s>
<s>
When	O
used	O
in	O
conjunction	O
with	O
photolithography	B-Algorithm
,	O
silicon	O
dioxide	O
can	O
be	O
selectively	O
applied	O
or	O
removed	O
to	O
trace	O
paths	O
for	O
circuits	O
.	O
</s>
<s>
This	O
can	O
be	O
done	O
with	O
a	O
plasma	B-Algorithm
etcher	I-Algorithm
.	O
</s>
<s>
This	O
is	O
also	O
done	O
in	O
a	O
special	O
plasma	B-Algorithm
etcher	I-Algorithm
,	O
called	O
an	O
asher	O
.	O
</s>
<s>
Plasma	B-Algorithm
etchers	I-Algorithm
are	O
also	O
used	O
for	O
de-layering	O
integrated	O
circuits	O
in	O
failure	O
analysis	O
.	O
</s>
