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From: przemek@gondor.cs.psu.edu (Przemyslaw Klosowski)
Newsgroups: rec.ham-radio,sci.electronics
Subject: Re: build-it-yourself EPROM erasers (Just the facts)
Message-ID: <3299@psuvax1.psu.edu>
Date: 17 Feb 88 21:25:59 GMT
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Reply-To: przemek@gondor.cs.psu.edu (Przemyslaw Klosowski)
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 This is written in response to the long and basically correct article 
about the  physics of the EPROM. It explained th phenomenon correctly, but
omitted the quantitative expression for the process: one expression is worth 
1000 words :^)
The physics of this process is  simply of a dynamically activated system:
the probability of the electron passing the barrier (and consequently 
the current, and the time to discharge the gate) is proportioonal to

			      E-E
			         0		where   e=2.7182818...
			   - -----			E - electron energy
			       kT			k is Boltzman const 
			e				T is temperature
							E  is activation energy
							 0


So: ypu can either raise the energy of the electrons ( by  bombarding  with
UV light quanta) or raise the temperature. But you better raise it  enough!
UV has energy of ~3eV. Room temp kT is 25 meV; or in other   words you have to 
raise  temp to 120 * 300 K or 36000K to get the same discharge speed, if I got
my numbers right. This is impractical :^)
				przemek@psuvaxg.bitnet
				psuvax1!gondor!przemek