Xref: utzoo rec.ham-radio:3887 sci.electronics:2093
Path: utzoo!utgpu!jarvis.csri.toronto.edu!utcsri!uthub!koko
From: koko@uthub.toronto.edu (M. Kokodyniak)
Newsgroups: rec.ham-radio,sci.electronics
Subject: Re: build-it-yourself EPROM erasers
Message-ID: <698@uthub.toronto.edu>
Date: 12 Feb 88 19:58:36 GMT
Article-I.D.: uthub.698
Posted: Fri Feb 12 14:58:36 1988
References: <8802091255.AA23298@ucbvax.Berkeley.EDU> <12@ucsd.EDU> <21651@clyde.ATT.COM>
Organization: CSRI, University of Toronto
Lines: 20
Keywords: EPROM eraser
Summary: fried chips

In article <21651@clyde.ATT.COM>, gwu@clyde.ATT.COM (George Wu) writes:
> ...
>      Anyways, the reasoning goes something like this: the UV light is just
> some extra energy you're giving to release trapped electrons. So why not use
> some other form of energy, like heat?
> 
>      This has actually been successfully done, although I can't remember the
> temperature or time. I think it was half an hour at 300 degrees. ...

I would not want to try this, or at least not to often, since the heat may
destroy the device.  Components in the silicon wafer are formed during the
manufacturing process by controlled diffusion of impurities into selected
areas in the wafer.  Further heating might cause further diffusion which
would make these components gradually disappear.

Why else would all data sheets for silicon integrated circuits specify
a maximum ambient temperature?

Another potential problem is cracking -- this might not even be visible --
because of non-uniform heating or cooling.