In a message dated 3/24/99 8:35:26 AM Pacific Standard Time,
[log in to unmask] writes:
<< Just a general inquiry on this cleaning issue: A while back when cleaning
alternatives was the subject of the day, the use of ultrasonics was one of
the viable candidates. Discussions always went like," ...ultrasonic
cleaning works great, but..." and then the stuff about possible part damage
scared everybody off. I always thought somebody would do a study
demonstrating liklihood of damage, or come up with a system that would be
safe for most parts, but the technology seems to just be sitting in the back
of the bus, not banned but not really used either. Are there actual
instances where responsible use of ultrasonics affected an assembly's
reliability?
Ralph Vaughan >>
Hi Ralph,
You know, I've often wondered the same thing. As good cleaning as
ultrasonics are, I wondered why somebody hasn't taken the ball and run with
it. But apparently there has been somebody. A company called CAE Ney, they've
been in ultrasonics for quite a few years.
From what I've learned just this morning, is that ultrasonics have come a
long way since the fear of destroying wire bonds of years ago. The ultrasonic
energy being used in most cleaners was at a fixed frequency, and there was
lots of it. It was learned that bubble cavitation was what cleaned, and using
"Tim Allen's" logic, if a few bubbles cleaned good, then a whole bunch more
would clean even better! You know the mo' power thing...arrrrgh! arrrrgh!
arrrrgh! (GRIN)
But now, the technology has gone into multiple frequencies, and they can
be programmed to change at a certain rate during the cleaning cycle. There's
also what's being called "sweeping frequencies" to eliminate "dead spots" in
the tanks, and to avoid setting up harmonics inside the parts themselves which
would cause all the damage to parts in the past...a harmonic would develop and
you would get a standing wave that the die or wire would start vibrating at of
the frequency that was being generated for the ultrasonics, then snap,
crackle, pop...that's NOT rice krispies! With the ultrasonic technology that's
out there now, there should be no reason in the world not to use ultrasonics.
It's just a matter of controlling the energy and frequencies that you use to
do the cleaning. Here's a little blurb on CAE Ney's product that shows how
much things have changed:
New multiSONIK™ Generator
CAE Ney introduces the multiSONIK™ Multiple Frequency Ultrasonic Generator.
Representing a major breakthrough in ultrasonic cleaning technology, the
multiSONIK™ is an advanced digital ultrasonic generator that provides the
ability to select single or multiple frequencies for a single process tank.
Featuring CAE Ney's patented dual sweep technology, the multiSONIK™ can
operate at 40, 72, 104 or 170kHz frequencies according to a pre-determined
sequence, or it can be programmed to alternate randomly between frequencies.
With a multi-frequency generator driving CAE Ney's unique universal
transducer, cleaning performance is optimized to a level not previously
achievable with conventional ultrasonic cleaning. This new, advanced
technology revolutionizes sub-micron particle removal in the critical cleaning
of microelectronics, flat panels displays, disk drive components and
assemblies, semiconductors, optics and more. The new multiSONIK™ technology
permits the exposure of components to a selectable or continually changing
array of application-specific ultrasonic cleaning frequencies from just one
generator to optimize your precision cleaning
1999 Trade Show Schedule
Date Show Location Booth
February 23-25 NEPCON West Anaheim, CA 6410
May 18-20 CleanTech Rosemont, IL 115-123
May 25-27 MD & M New York, NY 1775
July 12-14 SEMICON West San Francisco,CA
September 21-23 DISKCON San Jose, CA 2637
Another company I found that has had some exposure to cleaning printed circuit
assemblies using ultrasonic is a company called Megasonics. They make
ultrasonic energy and frequency monitors that one uses to check these things
in the tank...kinda' like a calibration tool. I spoke with a gentleman there
this morning and he's said the same thing, that things have come a long way
since 10-years ago. There's a lot of companies that have been starting to use
ultrasonics a lot more since they've looked into how safe and effective they
can be. Here's a little blurb from Megasonics WEB page:
"We began selling our first Ultrasonic Energy Meter in January of 1996. Since
then our customers for the Ultrasonic Energy Meter have included Seagate,
Western Digital, Hyundai, Read-Rite, Tektronix, Motorola, Corning, and others.
The industries typically fall in the electronic (including disk drive),
pharmaceutical, aerospace, automotive, and machine parts cleaning and
manufacturing markets."
CAE Ney can be reached at:
http://www.Neysonics.com
Phone: (860) 286-8877
...and you can check some of their generators (with pics and every stuff) at:
http://www.Neysonics.com/Generators.html
Megasonics can be reached at:
http://www.megasonics.com
(650) 851-4387
-Steve Gregory-
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