Phase change memory device and method of fabricating the same

Details Phase change memory device and method of fabricating the same Phase change memory device and method of fabricating the same

2011-07-12

2011-07-12

Landau, Matthew C (Department: 2813)

Active solid-state devices (e.g., transistors, solid-state diode

Semiconductor is selenium or tellurium in elemental form

C257S002000, C257SE31029, C438S102000, C438S103000

Reexamination Certificate

active

07977674

ABSTRACT:
A phase change memory device and a method of fabricating the same are provided. A phase change material layer of the phase change memory device is formed of germanium (Ge)-antimony (Sb)-Tellurium (Te)-based Ge2Sb2+xTe5(0.12≦x≦0.32), so that the crystalline state is determined as a stable single phase, not a mixed phase of a metastable phase and a stable phase, in phase transition between crystalline and amorphous states of a phase change material, and the phase transition according to increasing temperature directly transitions to the single stable phase from the amorphous state. As a result, set operation stability and distribution characteristics of set state resistances of the phase change memory device can be significantly enhanced, and an amorphous resistance can be maintained for a long time at a high temperature, i.e., around crystallization temperature, and thus reset operation stability and rewrite operation stability of the phase change memory device can be significantly enhanced.

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