Multi-level programming of phase change memory device
AssigneeInternational Business Machines Corporation
InventorsKangguo Cheng, Juntao Li, Ching-Tzu Chen, Carl Radens
Life of this patent
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Abstract
A phase change memory includes a phase change structure. There is a heater coupled to a first surface of the phase change structure. A first electrode is coupled to a second surface of the phase change structure. A second electrode coupled to a second surface of the heater. A third electrode is connected to a first lateral end of the phase change structure and a fourth electrode connected to a second lateral end of the phase change structure.
Claims20
A phase change memory cell, comprising:
- a phase change structure;
- a heater coupled to a first surface of the phase change structure;
- a first electrode coupled to a second surface of the phase change structure;
- a second electrode coupled to a second surface of the heater;
- a third electrode connected to a first lateral end of the phase change structure;
- and
- a fourth electrode connected to a second lateral end of the phase change structure,
- wherein the phase change structure comprises a stack of alternating layers of a resistive liner (RL) layer and a phase change memory (PCM) layer and a thickness of at least one PCM layer in the stack of alternating layers of the RL layer and the PCM layer is different from thicknesses of other PCM layers in the stack of alternating layers.
A method of fabricating a phase change memory cell, comprising:
- providing a bottom electrode;
- creating a phase change structure above and coupled to the bottom electrode at a bottom surface of the phase change structure;
- forming a left electrode and a right electrode on a left vertical side surface and a right vertical side surface of the phase change structure, respectively;
- forming a heater on top of and coupled to a top surface of the phase change structure;
- and
- providing a top electrode on top of and coupled to a top surface of the heater,
- wherein the phase change structure comprises a stack of alternating layers of a resistive liner (RL) layer and a phase change memory (PCM) layer and a thickness of at least one PCM layer in the stack of alternating layers of the RL layer and the PCM layer is different from thicknesses of other PCM layers in the stack of alternating layers.
A phase change memory cell, comprising:
- a phase change structure;
- a heater coupled to a first surface of the phase change structure;
- a first electrode coupled to a second surface of the phase change structure;
- a second electrode coupled to a second surface of the heater;
- a third electrode connected to a first lateral end of the phase change structure;
- and
- a fourth electrode connected to a second lateral end of the phase change structure,
- wherein the phase change structure comprises a stack of alternating layers of a resistive liner (RL) layer and a phase change memory (PCM) layer and a thickness of at least one RL layer in the stack of alternating layers of the RL layer and the PCM layer is different from thicknesses of other RL layers in the stack of alternating layers.
Dependencies are inferred from the claim text.