TECHNET Archives

November 2000

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:
Earl Moon <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Wed, 15 Nov 2000 10:34:31 -0600
Content-Type:
text/plain
Parts/Attachments:
text/plain (23 lines)
It is clear you've considerable experience soldering, in general, and BGA's.
Someone knows why the balls don't wet to the paste "mound" though they
collapse as typical. My question remains considering whether this "mound"
wets, or not, to the solder termination pads. If it does not wet their
either (in addition to the balls), what is of primary concern - provided
your profile is as you say (looks ok for some pastes considering the 185 [56
seconds may be low] window and liquidous [how much time here?]?

You know the heat is concentrated at the BGA corners. If the profile is low,
your corners may wet while edge balls do not - or may be wetting marginally.
Still feel uncomfortable with ball collapse but not wetting to the "mounds."

Earl Moon

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------

ATOM RSS1 RSS2