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| United States Patent | 6,125,062 |
| Ahn, et. al. | Sept. 26, 2000 |
Abstract
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 |
| 4,939,559 | Jul., 1990 | DiMaria | 257/321 |
| 5,731,598 | Mar., 1998 | Kado et al. | 257/30 |
| 5,740,104 | Apr., 1998 | Forbes | 365/185.03 |
| 5,952,692 | Sept., 1999 | Nakazato | 257/321 |
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