|
EESemi.com Forum Archives
Decapsulation
Dilemma - Melting Copper Wires
Proper device
failure analysis can not be performed unless
the sample can be decapsulated nicely. Different plastic molding
compounds and the internal features of the device react to the
decapsulating etchant in different ways. As such, successful
decapsulation of the part requires that the
correct etchant recipe is applied.
But what if a failure analysis lab's standard recipes can not
decapsulate a new device? The archived forum thread below discusses the
decapsulation dilemma of the thread starter, who observed that the
copper wires of his sample is being dissolved by the etchant he was
using.
|
Posted by Rivs: Wed
Aug 08, 2007 10:49 am Post
subject: HYSOL MG15F MOLDING COMPOUND |
|
|
|
Guys need your idea on
this.... We currently have an evaluation on copper wire
bonding (2 mils) the problem is during failure analysis
chemical decapsulation, copper wire were
etched/dissolved after the unit is fully decapped using
sulfuric acid. As experienced MG15F molding compound
does not react on Nitric red fuming.
Hope you can give us any idea on how we can decap the
parts without over etching/dissolving the copper wire.
Thanks. |
|
| |
|
Posted by Paulpang:
Thu Aug 09, 2007 8:37 pm
Post subject: |
|
|
|
Hi Rivs:
Try to use the formula: Sulfuric acid : nitric acid= 3
:1 or (2:1)
I am also working on copper wire decap in recently. Good
luck in your FA process.
regards,
paul |
|
| |
|
Posted by Paulpang:
Thu Aug 09, 2007 8:39 pm
Post subject: |
|
|
|
Take note: sulfruic acid (96%),
nitric acid (98%)-----paul |
|
| |
|
Posted by Rivs: Fri
Aug 10, 2007 8:23 am Post
subject: |
|
|
|
Hi Paul, Thanks for the
response. I'll try this and give you feedback on the
result. Anyway fyi I'ved tried this mixture in a 9:1 and
5:1 ration (Nitric:Sulfuric) but none of them worked.
Again thanks. |
|
| |
|
Posted by Paulpang:
Sat Aug 11, 2007 7:41 pm
Post subject: |
|
|
|
Hi Rivs:
The decap you finished by manual decap or auto decap? I
carried out it by manual. Keep in touch....
regards,
paul |
|
| |
|
Posted by Rivs: Mon
Aug 13, 2007 3:55 pm Post
subject: |
|
|
|
Hi paul, I am doing it
manually by submerssion method, the ratio you gave
did'nt work, the Nitric acid just vaporized and the
package of the unit is still solid, just like our
mixture of 5:1 (Nitric:Sulfuric), are you successfull
with what you did? |
|
| |
|
Posted by Paulpang:
Mon Aug 13, 2007 8:44 pm
Post subject: |
|
|
|
Hi Rivs:
It will be easy to control if you perform decap by
manual. If the compound can not dissolve then,
1.) take the unit out of chemical.
2.) use aceton to wash the unit
3.) put the unit into chemical again
4.) compound still can not dissolve
repeat step 1 to 4.
thus, you'll find differnce.
By the way, what temperature did you set ? 250 deg would
be prefered.
regards,
paul |
| |
|
|
|
Back to the 'Best of Forums' Archives
HOME
Copyright
©
2009
EESemi.com.
All Rights Reserved. |
|
|
