Electronic switching in phase-change memories

A detailed investigation of electronic switching in chalcogenide-based phase-change memory devices is presented. An original bandgap model consistent with the microscopic structure of both crystalline and amorphous chalcogenide is described, and a physical picture of the switching mechanism is proposed. Numerical simulations provide, for the first time, a quantitative description of the peculiar current-voltage curve of a Ge/sub 2/Sb/sub 2/Te/sub 5/ resistor, in good agreement with measurements performed on test devices.