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:
Jul. 13, 1999
Filed:
Oct. 24, 1997
Li Yeat Chen, Hsinchu, TW;
Ing-Ruey Liaw, Hsinchu, TW;
Vanguard International Semiconductor Corporation, Hsin-Chu, TW;
Abstract
A method of forming a capacitor having a cross section shape similar to the Greek letter psi. The shape of the capacitor plate provides a high capacitance using a modest amount of chip area. A capacitor hole is etched in a thick layer of a first dielectric. A layer of polysilicon is formed on the dielectric layer covering the sidewalls and bottom of the capacitor hole. A second dielectric is then used to fill the hole. A contact hole in the second dielectric extends to the contact region of the wafer and is filled with a polysilicon plug. The polysilicon plug and the polysilicon covering the sidewalls and bottom of the capacitor hole form the first capacitor plate. A layer of hemispherical grain polysilicon can be used to further increase the surface area of the first capacitor plate.