Sender: |
|
X-To: |
|
Date: |
Wed, 13 May 1998 20:41:29 -0700 |
Reply-To: |
|
Subject: |
|
From: |
|
Content-Transfer-Encoding: |
7bit |
Content-Type: |
text/plain; charset=us-ascii |
Organization: |
ec |
MIME-Version: |
1.0 |
Parts/Attachments: |
|
|
Alvin Leong wrote:
>
> Hi Technetee,
> Anyone experience the solder ball appearing in the no-clean process?
> What is the contributor? I forseen a misprinted PCB on the solder paste
> station is one of it.
> 1. What is the recommendation on the smear board cleaning procedure?
> 2. Ultra-sonic cleaner?
> 3. What type of chemical?
> 4. If an ultra-sonic is the solution, then what is the side impact to
> the package on double-sided process?
>
> Hope anyone can share the info.
>
> Thks.
>
> ################################################################
> 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 web site (http://jefry.ipc.org/forum.htm) for additional information.
> For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
> ################################################################Generally,in the no clean process, as I understand, solder balls are more
prevalent.
You can try the following to see if it helps:
1. Lower preheat temperature
2. Is there sufficient flux on the board?(wave solder)
3. Soldermask: glossy or matte? The matte masks are less [prone to
solder balls.
4. Is mask properly cured? Try an extended UV cycle to harden the
mask.
Good luck
################################################################
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 web site (http://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################
|
|
|