Reprogrammable EEPROM With Super-Ionic Conductor/Semiconductor Sandwich Structure
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07
For reprogrammable EPROMs (EEPROM) a reversible, but non-volatile, write process and a non-destructive sense process are required. This EEPROM exploits the change in resistivity which can be produced by electrolytic deposition and removal of a metal film on a high-resistance substrate. A film 1 of a solid-state electrolyte is sandwiched in between a metal electrode 2 and a high-resistivity counter electrode 3. Counter electrode 3 carries a contact 4 on the surface opposite film 1. Two further contacts 5 and 6 are placed in juxtaposition with film 1. The electrolyte-forming film 1 may be a cationic conductor, e.g., from the AgI group. Alternative electrolytes are b-alumina or gallate. The top electrode 2 consists of the parent metal, i.e., silver in the case of an AgI electrolyte.