Brochure

The Third Dimension
Some acceptability criteria refer to a side view and many
defects can be seen best from the side, in other words, some
information about the vertical dimension is required.
phoenix|x-ray systems provide this information by oblique view
– up to 70 degrees – at highest magnification. As an
example, this enables the user to see open BGA solder joints
directly instead of interpreting signatures.
Just look from the side
ovhm ‑ oblique views at highest magnification
X-ray tube
0 - 70°
detector
Conventional tilting vs. ovhm
Technology
ovhm: Oblique views at highest
magnications
Conventional tilt techniques generate
oblique views by simply tilting the sample
to the side, which involves moving one part
of the sample further away from the X-ray
tuberesultinginadecreaseinmagnica-
tion.Theovhm|modulewasspecically
designed to enable oblique views of up to
70 degrees and 0 to 360 degree rota-
tionswithoutadecreaseinmagnication.
Magnicationremainsthesamebecause
the distance between focus and sample
does not change while the detector is be-
ing tilted.
BGA
PCB
Scheme of non‑wetted BGA land and its detection by
ovhm: the land is empty
BGA
PCB
Scheme of non‑wetted BGA ball and its detection by ovhm:
paste solder and ball are separated
Leads
PCB
Scheme of THT solder joints and their inspection by ovhm: one
through-hole is not lled and the hole plating is not wetted by
the solder
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ovhm: oblique views give excellent information in the vertical direction. At 70 degrees
the prole of these CSP solder joints is fully displayed and even the void position can
be clearly determined. In contrast to 45 degrees, at 70 degrees the component and
board pads are completely separated and can be inspected without any interference.
70°
45°
0°
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