Dome-shaped phase change memory mushroom cell
AssigneeInternational Business Machines Corporation
InventorsJuntao Li, Kangguo Cheng, LOUIS ZUOGUANG LIU, Arthur Roy Gasasira
Life of this patent
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Abstract
A mushroom memory cell may be formed by depositing a second dielectric layer on top of a first dielectric layer and a heater, depositing a hard mask on top of the second dielectric layer, performing a directional reactive-ion etching to remove an exposed portion of the second dielectric layer, performing a lateral etching to remove a portion of the second dielectric layer under the hard mask, performing directional deposition of a phase change material (PCM) over the heater, depositing a covering dielectric over the PCM, performing a second directional etching to expose a top surface of the PCM, and depositing a top electrode on the surface of the PCM.
Claims20
A method of creating a memory cell comprising:
- depositing a second dielectric layer on top of a first dielectric layer and a heater;
- depositing a hard mask on top of the second dielectric layer;
- performing a directional reactive-ion etching to remove an exposed portion of the second dielectric layer;
- performing a lateral etching to remove a portion of the second dielectric layer under the hard mask;
- performing directional deposition of a phase change material (PCM) over the heater;
- depositing a covering dielectric over the PCM;
- performing a second directional etching to expose a top surface of the PCM;
- and
- depositing a top electrode on the surface of the PCM.
A memory cell device comprising:
- a phase change material (PCM) over a heater;
- and
- a dielectric surrounding the PCM.
A method comprising:
- applying an electrical current to a bottom electrode of a memory cell;
- increasing a temperature, based on the applied electrical current, of a heater electrically connected to the bottom electrode;
- forming an amorphous dome in a shaped phase change material (PCM) thermally and electrically connected to the heater based on the increasing temperature of the heater;
- and
- recording a resistance from the bottom electrode to a top electrode, where the top electrode is electrically connected to the PCM.
Dependencies are inferred from the claim text.