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|United States Patent||6,407,426|
|Ahn ,   et al.||June 18, 2002|
A memory device includes 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 have a maximum dimension of three to five nanometers and are surrounded by an insulator having a thickness of between five and twenty nanometers. 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, NY)|
|Assignee:||Micron Technology, Inc. (Boise, ID)|
|Filed:||October 31, 2000|
|Current U.S. Class:||257/331; 257/30; 257/39|
|Intern'l Class:||H01L 027/108|
|Field of Search:||257/331,30,39|
|5323344||Jun., 1994||Katamaya et al.||365/162.|
|5485595||Jan., 1996||Assar et al.||395/430.|
|5681770||Oct., 1997||Ogura et al.||438/257.|
|5731598||Mar., 1998||Kado et al.||257/30.|
|5952692||Sep., 1999||Nakazato et al.||257/321.|
|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.