Memory cell of nonvolatile semiconductor memory
AssigneeKabushiki Kaisha Toshiba
InventorsShoko Kikuchi, Akira Takashima, Naoki Yasuda, Koichi Muraoka
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Abstract
A memory cell of a nonvolatile semiconductor memory includes a semiconductor region, source/drain areas arranged separately from each other in the semiconductor region, a tunnel insulating film arranged on a channel region between the diffusion areas, a floating gate electrode arranged on the tunnel insulating film, an inter-electrode insulator arranged on the floating gate electrode, and a control gate electrode arranged on the inter-electrode insulator. The inter-electrode insulator includes lanthanoid-based metal Ln, aluminum Al, and oxygen O, and a composition ratio Ln/(Al+Ln) between the lanthanoid-based metal and the aluminum takes a value within the range of 0.33 to 0.39.
Claims20
A memory cell comprising:
- a semiconductor region;
- source/drain areas arranged separately from each other in the semiconductor region;
- a tunnel insulating film arranged on a channel region between the diffusion areas;
- a floating gate electrode arranged on the tunnel insulating film;
- an inter-electrode insulator arranged on the floating gate electrode;
- and
- a control gate electrode arranged on the inter-electrode insulator,
- wherein the inter-electrode insulator includes lanthanoid-based metal Ln, aluminum Al, and oxygen O, and all of the inter-electrode insulator has a composition ratio of Ln/(Al+Ln) having a value within the range of 0.33 to 0.39.
A memory cell comprising:
- a semiconductor region;
- source/drain areas arranged separately from each other in the semiconductor region;
- a tunnel insulating film arranged on a channel region between the diffusion areas;
- a charge trap layer arranged on the tunnel insulating film;
- a blocking insulator arranged on the charge trap layer;
- and
- a control gate electrode arranged on the blocking insulator,
- wherein the blocking insulator includes lanthanoid-based metal Ln, aluminum Al, and oxygen O, and a composition ratio Ln/(Al+Ln) between the lanthanoid-based metal and the aluminum takes a value within the range of 0.33 to 0.39.
Dependencies are inferred from the claim text.