First, x-ray inspection machines have a wide range of capilities. Resolution is a key measure of a machine's ability to "distinguish" features. People say that some x-ray inspection machines have the ability to position the board being inspected at diffent angles that some say aids in finding cracks. [I've never used that style of equipment.]
Second, there's lots of causes of BGA opens [eg, mechanical stress, poor pad plating, poor soldering, secondary solder opens]. A boss might agrue that YOU can devine differences in appearance between each of these balls and a good ball. I wouldn't buy it, if he was my supplier.
We had a similar conversation within the past year [??] on SMTnet. Check the Archives.
If you can find opens with x-ray, you are lucky. Acoustic microscopy is a much more repeatable technique. [Although I've heard some argue that ultrasonic technoques require extensive intrepetation.] The space between the solder on either side of the open make a distinctive white "glow" that requires limited "special skills" to determine opens. It ain't rocket science. Trust me.
X-ray laminography can show opens, but it is likely to be prohibitively expensive in most applications
Taking a different tact, I'd speculate that opens are easier to find with an ERSAscope than x-ray. Mucho cheaper if it truely does work!!
Finally if your boss is correct and your x-ray inspection machine is capable of trouble-shooting BGA opens, your inspection machine supplier should be able to demonstrate that capability. Call 'em up.
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Hello,
I have been told to look for open BGA connections,...
- Mar 14, 2001
by
Christopher Lampron
Reading x-rays is an art. All balls should be symmetrical in...
- Mar 14, 2001
by
CAL
