Semiconductor device and method for producing the same
AssigneeUnisantis Electronics Singapore Pte. Ltd.
InventorsFujio MASUOKA, Hiroki NAKAMURA
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Abstract
A memory device includes memory elements arranged in two or more rows and two or more columns. Each memory element includes a pillar-shaped insulator layer, a phase change film around an upper portion of the pillar-shaped insulator layer, a lower electrode formed around a lower portion of the pillar-shaped insulator layer and connected to the phase change film, a reset gate insulating film surrounding the phase change film, and a reset gate surrounding the reset gate insulating film. The reset gates are connected to one another in a row direction and a column direction, and are heaters. The phase change films are electrically insulated from the reset gates. A method for producing the memory device is also provided.
Claims21
A memory device comprising:
- a plurality of memory elements arranged in two or more rows and two or more columns, each memory element comprising:
- a pillar-shaped insulator layer,
- a phase change film formed around an upper portion of the pillar-shaped insulator layer,
- a lower electrode formed around a lower portion of the pillar-shaped insulator layer and connected to the phase change film,
- a reset gate insulating film surrounding the phase change film, and
- a reset gate surrounding the reset gate insulating film,
- wherein the reset gates are connected to one another in a row direction and a column direction,
- the reset gates are heaters, and
- the phase change films are electrically insulated from the reset gates.
A method for producing a memory device, the method comprising a sixth step that includes:
- depositing a second interlayer insulating film on a substrate, forming contact holes arranged in two or more rows and two or more columns, and depositing a second metal and a nitride film;
- removing the second metal and the nitride film on the second interlayer insulating film so as to form, inside the contact holes, pillar-shaped nitride film layers arranged in two or more rows and two or more columns, and form lower electrodes surrounding the pillar-shaped nitride film layers and bottom portions thereof and being arranged in two or more rows and two or more columns;
- etching back the second interlayer insulating film so as to expose upper portions of the lower electrodes surrounding the pillar-shaped nitride film layers;
- removing the exposed upper portions of the lower electrodes surrounding the pillar-shaped nitride film layers;
- depositing a phase change film so that the phase change film surrounds the pillar-shaped nitride film layers and connects with the lower electrodes;
- etching the phase change film into a side wall shape remaining on upper portions of the pillar-shaped nitride film layers;
- and
- forming a reset gate insulating film that surrounds the remaining phase change film and forming a reset gate that surrounds the phase change film having the side wall shape and remaining on the upper portions of the pillar-shaped nitride film layers arranged in two or more rows and two or more columns.
Dependencies are inferred from the claim text.