<s>
Scanning	B-Algorithm
near-field	I-Algorithm
ultrasound	I-Algorithm
holography	I-Algorithm
(	O
SNFUH	O
)	O
is	O
a	O
method	O
for	O
performing	O
nondestructive	O
nano-scale	O
high-resolution	O
imaging	O
of	O
buried	O
and	O
embedded	O
structures	O
.	O
</s>
<s>
Scanning	B-Algorithm
near-field	I-Algorithm
ultrasound	I-Algorithm
holography	I-Algorithm
combines	O
atomic	O
force	O
acoustic	O
microscopy	O
and	O
ultrasonic	O
force	O
microscopy	O
.	O
</s>
<s>
Two	O
transducers	B-Algorithm
producing	O
high	O
frequencies	O
are	O
used	O
.	O
</s>
<s>
One	O
transducer	B-Algorithm
is	O
placed	O
below	O
the	O
sample	O
and	O
the	O
other	O
attached	O
to	O
the	O
cantilever	O
.	O
</s>
<s>
The	O
cantilever	O
can	O
be	O
called	O
as	O
SPM	O
acoustic	O
antenna	O
which	O
senses	O
the	O
interference	O
of	O
acoustic	O
waves	O
sent	O
by	O
the	O
transducers	B-Algorithm
.	O
</s>
<s>
The	O
perturbations	O
to	O
phase	O
and	O
amplitude	B-Application
of	O
the	O
surface	O
acoustic	O
standing	O
wave	O
are	O
locally	O
monitored	O
by	O
the	O
antenna	O
via	O
the	O
lock-in	O
approach	O
and	O
the	O
SPM	O
electronic	O
module	O
.	O
</s>
<s>
This	O
technique	O
takes	O
advantage	O
of	O
both	O
the	O
phase	O
and	O
amplitude	B-Application
of	O
scattered	O
ultrasound	O
waves	O
to	O
produce	O
nanoscale	O
resolution	O
images	O
of	O
internal	O
substructures	O
.	O
</s>
