Re: Broken TED for visual6502.org

From: Gerrit Heitsch <gerrit_at_laosinh.s.bawue.de>
Date: Sat, 14 Jul 2012 19:03:21 +0200
Message-ID: <5001A659.2020501@laosinh.s.bawue.de>
On 07/13/2012 12:42 PM, Ingo Korb wrote:
> Gerrit Heitsch <gerrit@laosinh.s.bawue.de> writes:
>
>> Not that I can make out anything that looks like it's the cause for the
>> chip no longer working.
>
> The structures at the lower left side, fourth pin from the bottom look
> like they may be damaged.

Yes, but that looks to me like something that happened during the 
removal of the plastic covering the die. Remember they use hot acid to 
do this. The die only survives that due to the passivation layer (SiO2, 
meaning quartz AFAIK). Unfortunatly, you can't cover the bonding pads 
with it so depending on the tolerances the damage there might just have 
been some acid getting where it shouldn't have gone.

  Gerrit


       Message was sent through the cbm-hackers mailing list
Received on 2012-07-14 18:00:14

Archive generated by hypermail 2.2.0.