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:
May. 25, 1999
Filed:
Sep. 30, 1997
Applicant:
Inventors:
Robert Ploessl, Glen Allen, VA (US);
Bertrand Flienter, Hopewell Junction, NY (US);
Assignee:
Siemens Aktiengesellschaft, Munich, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438243 ; 438692 ; 438700 ;
Abstract
Improved technique of forming trench capacitors without causing excessive erosion at the edges of the array region resulting from polishing. The erosion is reduced by providing a block mask to protect the array region while partially removing a portion of the hard mask used to etch the trenches in the field region. The partial etch equalizes the height of the hard mask in the array and field region after formation of the deep trenches by a reactive ion etch.