Ken Patel,
I agree with Brian Ellis, but to give you some more insight on Ionic
Contamination limits, I pulled my old copy of MIl-STD 2000. Based on Table
VII, you find the following upper control limits:
MIL-P-28809 Beckman / Markson: 10 micrograms NaCl / sq. in.
Omegameter: 14 micrograms NaCl / sq. in.
Ionograph: 20 micrograms NaCl / sq. in.
Ion Chaser: 32 micrograms NaCl / sq. in.
What that means is that for different test methods, there are varying
degrees of sensitivity (ionograph is more sensitive than omegameter). If you
(or anyone else) is interested, I have a report that explains this to you.
It's rather lengthy (15 Mbytes in PDF format) to send via E-Mail so I will
need you address, etc., to FED-Ex to you.
However, if you application requires a higher cleanliness standard, you can
(and should) reduce these upper control limits appropriately. I agree with
Brian that you should set the upper control limits for ionic contamination
found by the omegameter or ionograph.
For additional information on the omegameter and ionograph, you may want to
check out the following website: http://www.scscookson.com/instruments/.
If you are setting up a cleaning process, or have a problem with
cleanliness, your best bet would be to have the boards tested via Ion
Chromatography. That will tell you what ionic contamination is on the board,
and their respective quantities. We have this capability and you can call me
off-line about it.
Good Luck.
Lee Whiteman
Senior Manufacturing Engineer
ACI / EMPF
Telephone: (610) 362-1200; Ext. 208
FAX: (610) 362-1290
E-Mail: [log in to unmask] <mailto:[log in to unmask]>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]]On Behalf Of Ken Patel
> Sent: Wednesday, December 13, 2000 8:44 PM
> To: [log in to unmask]
> Subject: [TN] Ionic contamination Limit
>
>
> Guys,
> What is the acceptable Ionic contamination limit for Omegameter 600 and
> Inograph 500 both made by Alphametals?
>
> re,
> ken patel
>
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