Jeff
I apologise for this tardy response, but my laptop died a few days ago and I have been somewhat pre-occupied with attempts at resuscitation.
However, we have a suggestion to make in respect to your apparent problem.
As I understand it, you have an issue of circuit assembly reliability which you consider is caused by some synergistic influences within your manufacturing processes? If so, you should note that there are new standards under preparation to assist and that whilst these are awaited, you may wish to consider the following:
We have a new test system, Auto-SIR, with FMTA to accurately predict (PQV) and monitor (PQM) the quality and reliability of your product.
FMTA - Frequent Monitoring / Trend Analysis
PQV - Process Quality Validation
PQM - Process Quality Monitoring
I am sure you will be familiar with the following:
J-STD-001B - Manufacturing
J-STD-004 - Solder fluxes
IPC-CC-830 - Conformal Coating
IPC-SM-840 - Solder Masks / Resists
IPC-TM-650 - Test Methods Manual
IPC-9201 - SIR Test Handbook
These of course form the foundations of standards for Materials Characterisation and, it is hoped, Process Characterisation.
We can measure the actual effects of both Ionic and Non-Ionic contamination on the surface insulation resistance of your representative assembly under conditions of accelerated ageing, to better predict the reliability of your product.
As a result of no-clean processing and the increasing use of non-ionic additives in modern process chemistries, such as solder resists, fluxes/pastes etc., the ability to monitor their synergistic effects is now an essential element in quality control.
We can provide
a.. Very low test leakage current detection ( <10-12 A) providing far more sensitive analysis.
b.. Sample monitoring at 10 minute intervals. Thus giving far greater opportunity to detect Electro-Migration in the form of Dendrites. (We know that dendrites can form within 20 minutes.)
c.. Dendrite preservation to facilitate subsequent and separate failure analysis.
d.. Detection of CAF influences.
I appreciate that Ion Chromatography (IC) will be able to determine precisely what is on the circuit, but not whether the circuit will be reliable. SIR testing using these new techniques, is able to inform you of whether the circuit is reliable but not what is on the suface causing it. You need both, SIR then IC if you find a problem.
I hope that you will find this of interest and that you will contact me directly if you would like more info.
Please accept my apologies if this seems too close to an advert, I cleaned it up as best I could in the spirit of the TechNet.
HAVE A VERY MERRY XMAS AND A HAPPY, HEALTHY AND PROSPEROUS NEW YEAR
Graham Naisbitt
__________________________________________________________________________
[log in to unmask]
Concoat Ltd
Alasan House, Albany Park
Camberley GU15 2PL UK http://www.concoat.co.uk
Application Engineers in Chemical Compounds to the Electronics Industry
-----Original Message-----
From: Jeff Mallia <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
|
