How do they wash BGA parts?

[Jeff]

Just curious...Are BGAs mounted on boards with aqueous flux? Can the rinse
water get under there to removethe flux?

Thanks,

Jeff

 

[James Meyer]

Just curious...Are BGAs mounted on boards with aqueous flux? Can the rinse
water get under there to removethe flux?

Thanks,

Jeff

I could tell you how I wash my balls, but then I'd have to change my
name to Genome.

Jimnome

 

[Genome]

I could tell you how I wash my balls, but then I'd have to change my
name to Genome.

Jimnome

Would that be a ladle, a toothbrush and the morning water from an overnight
Steradent soak?

DNA

 

[Jim Meyer]

Would that be a ladle, a toothbrush and the morning water from an overnight
Steradent soak?

DNA

Think "automation". A trip through the car wash in a convertable
with the top down.

Jim

 

[John Larkin]

Just curious...Are BGAs mounted on boards with aqueous flux? Can the rinse
water get under there to removethe flux?

Thanks,

Jeff

Our assembler uses non-water-soluble rosin flux, and just leaves it
there.

John

 

[Vincent Himpe]

Just curious...Are BGAs mounted on boards with aqueous flux? Can the
rinse water get under there to removethe flux?

Thanks,

Jeff

Use low residue no clean solder paste. ( Multicore or Kester makes this )
Its non conductive and you can leave it there.
You can't really clean under the BGA unless with ultrasonic cleaning and a
highly volatile solvent.

If you go to real mass production assembly they will use vapor phase
soldering that leaves no residue whatsoever. ( the board exits out of the
oven completely clean )

Vapor phase uses heat transfer liquids. since the flux is soluble in this
liquid and dissolves before the solder melts all flux is removed
automatically.

Halden makes this liquid at 200 $ a gallon . The Vapour is scrubbed and the
transfer lquid recycles trought the machine.

Vapor pahse soldering is the only reliable method of soldering for complex
boards that have multiple BGA's on themi ( like computer motherboards)

 

[Aubrey McIntosh]

If you go to real mass production assembly they will use vapor phase
soldering that leaves no residue whatsoever. ( the board exits out of the
oven completely clean )

Vapor phase uses heat transfer liquids. since the flux is soluble in this
liquid and dissolves before the solder melts all flux is removed
automatically.

What about using an Indium compound, and plain old water as the heat
transfer liquid? The only problem I could envision is that Indium
might "wet" the solder mask.

Anyone tried it?
Can stuffed boards be exposed to steam for "a while?"


http://cgi.ebay.com/ws/eBayISAPI.dl...61&category=413&sspagename=STRK:MEBWA:IT&rd=1