<<I am trying to quantify the residues left over after reflow from no
clean solder
paste.  We have an omega meter in the facility that gives you an ionic
measurement (resistivity and NaCl/inch).  Is this an adquate
measurement?

I am qualifying new pastes, and there is a concern in the ICT area about

residues.  Are there any other alternative methods of quantifying solder
paste
flux residues?

-Teo Tijerina>>

+++++++++++++++++++++++++++++++++++++++++++++
Teo,
When no-cleans first appeared several years ago the residues were a big
problem for ICT and other probe type testing.  Almost all of the probe
manufacturers today can provide  HIGH and EXTRA HIGH spring force probes
that will penetrate the residues and provide good contact with the
circuit nodes.  These probe performance characteristics are as good if
not better than the low and standard force probes.  If the test fixtures
are vacuum actuated (versus mechancial) make sure that you have a good
vacuum source and board gasketing.    If your test fixtures have a high
probe counts it is possible to have pull down problems with vacuum
fixtures and may have to change them to mechanical hold down type.

################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe:   SUBSCRIBE TechNet <your full name>
To unsubscribe:   SIGNOFF TechNet 
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################