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United States Patent 6,125,062
Ahn, et. al. Sept. 26, 2000

Single electron MOSFET memory device and method


A memory device and related methods are described. The memory device includes a plurality of cells, each cell including a MOSFET having a source coupled to a first end of a channel, a drain coupled to a second end of the channel, a gate formed on a gate insulator and extending from the source to the drain and a plurality of conductive islands, each surrounded by an insulator, formed in the channel. The islands have a maximum dimension of three nanometers. The surrounding insulator has a thickness of between five and twenty nanometers. Each island and surrounding insulator is formed in a pore extending into the channel. As a result, the memory cells are able to provide consistent, externally observable changes in response to the presence or absence of a single electron on the island.

Inventors: Ahn; Kie (Chappaqua, NY); Forbes; Leonard (Corvallis, OR).
Assignee: Micron Technology, Inc. (Boise, ID).
Appl. No.: 140,624
Filed: Aug. 26, 1998
Intl. Cl. : G11C 7/00
Current U.S. Cl.: 365/189.07; 257/314
Field of Search: 257/314, 315, 321; 365/189.07

References Cited | [Referenced By]

U.S. Patent Documents
4,939,559Jul., 1990DiMaria 257/321
5,731,598Mar., 1998Kado et al. 257/30
5,740,104Apr., 1998Forbes 365/185.03
5,952,692Sept., 1999Nakazato 257/321

Other References

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Primary Examiner: Zarabian; A.
Attorney, Agent or Firm: Dorsey & Whitney LLP
27 Claims, 19 Drawing Figures

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