The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 24, 1991
Filed:
Jun. 22, 1990
Douglas B Butler, Colorado Springs, CO (US);
Ramtron Corporation, Colorado Springs, CO (US);
Abstract
A trench capacitor which has a plurality of capacitor plates separated by a dielectric within a trench on a substrate. A plate located closest to the wall of the trench may be a field shield and tied everywhere to ground. The other plate may be polysilicon. Said other plate may be tied to a source of variable potential. A plurality of sacrificial layers are established over the structure and the structure thus formed is then patterened and etched. A pass transistor is formed adjacent to the trench capacitor, and a connecting layer is established connecting the other plate of the trench capacitor to the source/drain region of the pass transistor. The connecting layer makes electrical contact to the other capacitor plate and source/drain of the pass transistor and is insulated from other layers in the capacitor and pass transistor. Bit lines and word lines can then be added, as known in the art.