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. 22, 1998
Filed:
Aug. 23, 1996
Liang-Choo Hsia, Taipei, TW;
Thomas Chang, Hsin-Chu, TW;
Mosel Vitelic, Inc., Hsinchu, TW;
Abstract
A method of forming a capacitor that has improved charge storage capability and a capacitor produced by such method are provided. The method utilizes an additional layer of oxide spacer consisting of a plurality of oxide layers deposited by two alternating methods of thermal CVD and plasma CVD. After a contact hole is first etched by a plasma etching technique, the hole is again etched by an etchant such as hydrogen fluoride which has a high selectivity toward oxide layers formed by the plasma CVD method and a low selectivity toward oxide layers formed by the thermal CVD method. As a result, a corrugated side-wall of the contact hole is formed which affords the capacitor cell with a substantially increased surface area leading to an improved charge storage capability.