[vcf-midatlantic] X-ray erasure of EPROMs, was Re: Getting Data off old Atari Floppies

[Jonathan Gevaryahu]

On 12/14/2015 7:47 PM, Dave McGuire via vcf-midatlantic wrote:
> On 12/14/2015 07:46 PM, Jonathan Gevaryahu via vcf-midatlantic wrote:
>>>>>> Yeah 300F was completely wrong, I was mixing baking floppies up with
>>>>>> baking EPROMS after x-ray (not UV!) based erasure (which really does
>>>>>> need 300F).
>>>>>    Can you tell me more about this?  Does baking somehow address the
>>>>> problem of surface state creation during X-ray erasure?
>>>>>
>>>>>    (I type this with a glance at a stack of trays containing several
>>>>> thousand non-windowed EPROM-based microcontrollers, and another glance
>>>>> over at my X-ray machine..)
>>>>      You forgot to mention your electron microscope.
>>>     Can an electron beam erase EPROMs nondestructively??
>> I know a UV laser can, but you need to live-decap (i.e. decap without
>> damaging the die or bond wires) the chip first. This is used by security
>> researchers to unset security bits etc on microcontrollers.
>    Well we know UV can.  That's just targeted UV.
>
>              -Dave
>
I don't have access to an X-ray source here, so I've never tried it.

-- 
Jonathan Gevaryahu
jgevaryahu at gmail.com
jgevaryahu at hotmail.com