<s>
Non	O
contact	O
wafer	B-Architecture
testing	O
is	O
a	O
normal	O
step	O
in	O
semiconductor	B-Architecture
device	I-Architecture
fabrication	I-Architecture
,	O
used	O
to	O
detect	O
defects	O
in	O
integrated	O
circuits	O
(	O
IC	O
)	O
before	O
they	O
are	O
assembled	O
during	O
the	O
IC	B-Algorithm
packaging	I-Algorithm
step	O
.	O
</s>
<s>
Probing	O
ICs	O
while	O
they	O
are	O
still	O
on	O
the	O
wafer	B-Architecture
normally	O
requires	O
that	O
contact	O
be	O
made	O
between	O
the	O
automatic	O
test	O
equipment	O
(	O
ATE	O
)	O
and	O
IC	O
.	O
</s>
<s>
A	O
set	O
of	O
mechanical	O
probes	O
will	O
often	O
be	O
arranged	O
together	O
on	O
a	O
probe	O
card	O
,	O
which	O
is	O
attached	O
to	O
the	O
wafer	B-Architecture
prober	O
.	O
</s>
<s>
The	O
wafer	B-Architecture
is	O
lifted	O
by	O
the	O
wafer	B-Architecture
prober	O
until	O
metal	O
pads	O
on	O
one	O
or	O
more	O
ICs	O
on	O
the	O
wafer	B-Architecture
make	O
physical	O
contact	O
with	O
the	O
probes	O
.	O
</s>
<s>
A	O
certain	O
amount	O
of	O
over-travel	O
is	O
required	O
after	O
the	O
first	O
probe	O
makes	O
contact	O
with	O
the	O
wafer	B-Architecture
,	O
for	O
two	O
reasons	O
:	O
</s>
<s>
There	O
are	O
numerous	O
types	O
of	O
mechanical	O
probes	O
available	O
commercially	O
:	O
their	O
shape	O
can	O
be	O
in	O
the	O
form	O
of	O
a	O
cantilever	O
,	O
spring	O
,	O
or	O
membrane	O
,	O
and	O
they	O
can	O
be	O
bent	O
into	O
shape	O
,	O
stamped	O
,	O
or	O
made	O
by	O
microelectromechanical	B-Architecture
systems	I-Architecture
processing	O
.	O
</s>
<s>
These	O
methods	O
use	O
tiny	O
RF	O
antennae	O
(	O
similar	O
to	O
RFID	B-Application
tags	I-Application
,	O
but	O
on	O
a	O
much	O
smaller	O
scale	O
)	O
to	O
replace	O
both	O
the	O
mechanical	O
probes	O
and	O
the	O
metal	O
probe	O
pads	O
.	O
</s>
