Subject: | |
From: | |
Reply To: | |
Date: | Thu, 11 Oct 2007 18:36:04 -0400 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Susan!
Unfortunately I am forced to do this all of the time! It is very very
dirty. We have a nice machine from Nicene for assisting with it--goes
for somewhere in the $50K range.
The only way to do this while the part is on the board is to very
carefully pick at it with a hot air jet and Xacto knife. You will
probably whack the die some--if you machine away some of the encapsulant
first it is a bit better. This will also probably burn your fingertips
a bit. You obviously won't save the wirebonds.
If you take the part off of the board:
The sulfuric acid will generally eat the aluminum pads and any organic
passivation on top of the die. The process is done at very high
temperatures (>200C). The nitric acid is done at around 70C and will
preferentially attack copper. Obviously the nitric is preferable but
some of the encapsulants refuse to succumb.
If you don't have a nice decapsulator like we do, then you can do the
dipping by making a cute little nichrome basket and bending the device
leads into the mesh. You of course need to do the process in a high
flow chemical hood, and I like to wear a supplied air respirator as a
backup.
Wayne Thayer
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Susan Hott
Sent: Thursday, October 11, 2007 2:21 PM
To: [log in to unmask]
Subject: Re: [TN] Dissolving SOIC casing
Thanks for the offer, but need to do it pretty quick here or farm out to
someone else.
Customer wants to see the die inside.
Susan
-----Original Message-----
From: R Sedlak <[log in to unmask]>
To: [log in to unmask]
Sent: Thu, 11 Oct 2007 1:55 pm
Subject: Re: [TN] Dissolving SOIC casing
Susan:
Why don't you send me one of these casings, and let me do some
experimenting, and give you a recommendation.
Rudy Sedlak
RD Chemical Company
1350 Pear Avenue
Mountain View CA 94043
Susan Hott <[log in to unmask]> wrote: Greetings to all I need to dissolve
the black "plastic" casing on an SOIC to see the die.? Does anyone know
what I can use to do this?
Thanks
Susan Mansilla Hott
Robisan Lab
________________________________________________________________________
Email and AIM finally together. You've gotta check out free AOL Mail! -
http://mail.aol.com
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
---------------------------------
Take the Internet to Go: Yahoo!Go puts the Internet in your pocket:
mail, news, photos & more.
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing
per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100
ext.2815
-----------------------------------------------------
________________________________________________________________________
Email and AIM finally together. You've gotta check out free AOL Mail! -
http://mail.aol.com
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
|
|