Immunity of phase change material to disturb in the amorphous phase
View Patent ↗Disturb from the reset to the set state may be reduced by creating an amorphous phase that is substantially free of crystal nuclei when programming the reset state in a phase change memory. In some embodiments, this can be achieved by using a current or a voltage to program that exceeds the threshold voltage of the phase change memory element, but does not exceed a safe current voltage which would cause a disturb.
1. A phase change memory comprising:
a pair of electrodes; and
a phase change material between said electrodes, said material forming the crystalline phase by crystal growth, wherein said material has a crystallization energy greater than 2.2 eV.
2. The memory of claim 1 wherein said material includes silver, indium, selenium, antimony, and tellurium.
3. The memory of claim 1 wherein said memory is a multilevel cell memory.
4. The memory of claim 1 wherein said memory is read by detecting its threshold voltage.
5. A phase change memory comprising:
a pair of electrodes; and
a phase change material including Ag 8 In 14 Sb 55 Te 23 between said electrodes, said material forming the crystalline phase by crystal growth.