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:
Mar. 07, 1995
Filed:
Jun. 30, 1994
Applicant:
Inventors:
Louis L Hsu, Fishkill, NY (US);
Sieki Ogura, Hopewell Junction, NY (US);
Joseph F Shepard, Hopewell Junction, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 52 ; 437 47 ; 437 60 ; 437919 ;
Abstract
A DRAM cell of the trench capacitor type is formed by a simplified process that reduces cost and increases process latitude by forming the trench collar in a single step of expanding a shallow trench horizontally and conformally coating the collar; etching the trench to its final depth and implanting the bottom heavily and doping the walls lightly; recessing the poly liner in a non-critical step that exposes a contact area between the top of the poly and the adjacent transistor electrode.