HASL and BGAs

[Colorado-PC-Dude]

All,

I know that HASL and BGAs don't go well together. Our manufacturing engineers are hollering 'cause HASL is cheap and familiar. Could I ask for arguments/reasons to explain to these guys why the surface needs to be as flat as possible?

Thanks,
Ben

[cadpro2k]

Another thought...

Low Volume.
Low Density.
Low tech.
Less than 800 pin count BGA.

Not a problem. I've done countless HASL BGA designs, without problems. But, when you do 'real' hi-tech boards... could be. That I don't know for an absolute.

But, like you've mentioned, if you have the options of going immersion gold or silver YOU'LL feel happier. PCD&M magazine had an article on this last month. Might check there.

Good day.