TECHNET Archives

April 2017

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:
haviv gendelis <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, haviv gendelis <[log in to unmask]>
Date:
Wed, 26 Apr 2017 18:05:47 +0300
Content-Type:
text/plain
Parts/Attachments:
text/plain (75 lines)
There os nothing to do with the design. Standard for RF boards.
Possible reasons
1. Material  should be min tg 170c
2. Poor board manufacturing  contamination, prepreg, lamination process
3. Water absorption
4. Assembly profile

The delamination could
appear in other areas but is hard to detect because of the Cooper shadow.
Haviv

On Apr 26, 2017 4:52 PM, "Carl Van Wormer" <[log in to unmask]>
wrote:

> We received pictures from our contract manufacturer, marked to show
> delamination occurring in 2 areas on our 6-layer boards.  The delamination
> areas were at the electrically isolated communication interfaces that were
> made with no copper on the power and ground planes to reduce capacitive
> coupling.  The response from the PCB manufacturer is:
>
> ​​​​​1)defect reason: we used our stock boards to run the thermal shock
> test, we see the de-lam is only taking place in the two areas without
> copper (pic 1.jpg),
>     There is insufficient glue in this area that happened during
> lamination and that is why the de-lam is happening when the customer is
> assembling under the high temp,
> 2)correction action:  if the customer needs us to remake, we suggest to
> modify the design a little, pls see pic 2.jpg, we will fill the marked area
> with solid copper .
> Please confirm if a remake is needed, we will arrange right away.
>
> Steve Gregory has posted the pictures at:
> http://stevezeva.homestead.com/Carl1.jpg (board cut open for evaluation
> at board house)
>
> http://stevezeva.homestead.com/Carl2.jpg (picture showing where they want
> to add copper)
>
> (and 2 pictures of the delaminated areas)
> http://stevezeva.homestead.com/Delamination_-_is_it_
> caused_by_missing_ground_plane__1_.jpg
> http://stevezeva.homestead.com/Delamination_-_is_it_
> caused_by_missing_ground_plane__2_.jpg
>
>
> Question to the group:  Will adding copper on the electrically isolated
> open areas eliminate this type of delamination?  We could add the copper,
> but not connect it to the system ground.
>
> Thanks,
> Carl
>
>
>
>
>
>
> Carl B. Van Wormer, P.E., AE7GD
> Senior Hardware Engineer
> Cipher Engineering LLC
>     21195 NW Evergreen Pkwy Ste 209
>     Hillsboro, OR  97124-7167
>     503-617-7447x303
>     [log in to unmask]<mailto:[log in to unmask]>
> http://cipherengineering.com<http://cipherengineering.com/>
>
> This message may contain confidential and/or proprietary information, and
> is intended for the person/entity to whom it was originally addressed. Any
> use by others is strictly prohibited.  If I sent this to you by mistake,
> please be nice and delete it, and then tell me of my mistake so I can send
> it to the right person.
>
>
>

ATOM RSS1 RSS2