摘要 |
A memory cell includes: a trench capacitor, including a trench silicon layer having an upper portion and a lower portion, and a buried plate disposed adjacent the lower portion of the trench silicon layer; an array FET having a gate portion, a drain portion, a source portion, and a buried strap coupled to one of the source and drain portions, the buried strap being in communication with the upper portion of the trench silicon layer; and a collar disposed about the upper portion of the trench silicon layer and between the buried strap and the buried plate, the collar including a re-entrant bend that is operable to decrease an electric field between the buried strap and the buried plate.
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