Phase-change memory cells

摘要

Phase-change memory cells for storing information in a plurality of programmable cell states. A phase-change component is located between first and second electrodes for applying a read voltage to the phase-change component to read the programmed cell state. The component includes opposed layers of phase-change material extending between the electrodes. A core component extends between the electrodes in contact with respective inner surfaces of the opposed layers. An outer component extends between the electrodes in contact with respective outer surfaces of the opposed layers. At least one of the core and outer component is formed of electrically-conductive material and is arranged to present, to a cell current produced by the read voltage, a lower-resistance current path than the amorphous phase of the phase-change material in any of said cell states. The current path has a length dependent on size of the amorphous phase in the opposed layers.

主权项

1. A phase-change memory cell for storing information in a plurality of programmable cell states, the memory cell comprising:
a phase-change component, of phase-change material, located between a first and a second electrode for applying a read voltage to the phase-change component to read the programmed cell state, the phase-change component having opposed layers of said phase-change material extending between the first and second electrodes; a core component extending between the first and second electrodes in contact with respective inner surfaces of said opposed layers; and an outer component extending between the electrodes in contact with respective outer surfaces of said opposed layers, wherein at least one of the core component and the outer component is formed of an electrically-conductive material and is arranged to present, to a cell current produced by the read voltage, a lower-resistance current path than an amorphous phase of said phase-change material in any of said programmed cell states, said lower-resistance current path having a length dependent on size of the amorphous phase in said opposed layers.