TECHNET Archives

June 1999

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Doug Pauls <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Wed, 16 Jun 1999 09:01:22 EDT
Content-Type:
text/plain
Parts/Attachments:
text/plain (71 lines)
In a message dated 06/15/1999 11:41:04 PM US Eastern Standard Time,
[log in to unmask] writes:

>
>  I'm looking for the IPC resistive spec. for the flux left behind after the
>  wave solder/ IR process on the finished assembly board.

I guess I wonder what you mean by resistive spec for fluxes.  This is not a
term used in any of the flux or assembly specifications that I know of.

If you are talking about surface insulation resistance, a measure of the
electrical isolation between two points on a circuit board, then you can look
in J-STD-004 (fluxes) or J-STD-001 (assemblies).  IPC-9201, the SIR Handbook,
would be good reading material.

If you are talking about the resistivity of solvent extract (ROSE), which is
a chemical characterization test used to determine ionic cleanliness, then
J-STD-001, section 8 is what you are looking for.  I would recommend reading
the corresponding section 8 in the J-STD-001 Handbook.

>
>  I've a couples of questions for anyone to address:
>  1.      How to measure the resistive flux residue on the finished assembly
board level?

Depending on the answers to the above, if you want to measure SIR on an
actual finished assembly, save your sanity and don't try unless your assembly
has built in test patterns.  Burn-in testing would be a better alternative.

If you are talking about cleanliness testing, the applicable test methods
from the IPC-TM-650 manual would be:
ROSE (beaker method) - 2.3.25
ROSE (static method) 2.3.26.1
ROSE (dynamic method) 2.3.26.2
Ion Chromatography (better than ROSE) 2.3.28
High Pressure Liquid Chromatography - 2.3.27.1
Residual Rosin by UV-VIS - 2.3.27

>          ( is it a common in the industry that requesting Sub-con house to
measure and control them)?

You would get as many different answers as you have OEMs.  In general, most
primes levy some form of cleanliness requirement on their subcontractors.
They type of requirement and the standards to meet vary widely.  J-STD-001
and IPC-A-610 are the most frequently referenced.

>  2.      What is the IPC  recommended resistive spec. for the flux residue
that left behind( referring to Non-clean process)

If you are talking SIR, then J-STD-004.  If you are talking cleanliness, an
IPC specification specific to no-cleans does not exist.  Les Hymes leads a
task group on no-clean implementation, but that is as close as it gets.
J-STD-001 is generic enough to encompass no cleans.


Doug Pauls
Technical Director
CSL

################################################################
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
################################################################


ATOM RSS1 RSS2