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United States Patent | 6,544,846 |
Ahn ,   et al. | April 8, 2003 |
A method of manufacturing a memory device including a plurality of cells, each having a first electrode coupled to a first location on semiconductor material, a second electrode coupled to a second location disposed away from the first location on the semiconductor material and a plurality of islands of semiconductor material. The islands are surrounded by an insulator. The islands and the surrounding insulator are formed in pores extending into the semiconductor material between the first and second electrodes. 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 Y. (Chappaqua, NY); Forbes; Leonard (Corvallis, OR) |
Assignee: | Micron Technology, Inc. (Boise, ID) |
Appl. No.: | 123580 |
Filed: | April 15, 2002 |
Current U.S. Class: | 438/257; 438/197; 438/264; 438/283; 365/185.29; 365/185.22; 257/531 |
Intern'l Class: | H10L 021/823.4 |
Field of Search: | 438/197,257,283,694,737,264 257/14,17,20,26,30,31,40,192,321,247,402 |
5323344 | Jun., 1994 | Katayama et al. | 365/162. |
5485595 | Jan., 1996 | Assar et al. | 395/430. |
5621687 | Apr., 1997 | Doller | 365/185. |
5681770 | Oct., 1997 | Ogura et al. | 437/43. |
5708605 | Jan., 1998 | Sato | 365/185. |
5731598 | Mar., 1998 | Kado et al. | 257/30. |
5740104 | Apr., 1998 | Forbes | 365/185. |
5754477 | May., 1998 | Forbes | 365/185. |
5952692 | Sep., 1999 | Nakazato et al. | 257/321. |
6121157 | Sep., 2000 | Nakajima | 438/737. |
6222778 | Apr., 2001 | Ahn et al. | 365/189. |
6301162 | Oct., 2001 | Ahn et al. | 365/189. |
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TABLE I Electron affinities .chi. for selected materials. .chi. (eV) Material Use 4.05 Si Islands 3.6/3.7* SiC Islands 1.4** C (diamond) Islands 0.9-4.05 Silicon oxycarbide (projected) Islands 0.9 SiO.sub.2 Gaps *depending on surface treatment. **diamond can manifest different values, including negative values.