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. 02, 2004
Filed:
Jul. 10, 2002
Jen-Chuan Pan, Hsinchu, TW;
Macronix International Co., Ltd., Hsinchu, TW;
Abstract
A method for fabricating a y-direction, self-alignment mask ROM device is described. The method includes forming a buried drain region in a substrate and forming a gate oxide layer on the substrate. Perpendicular to the direction of the buried drain region, a bar-shaped silicon nitride layer is formed on the gate oxide layer. A photoresist layer is then formed on the gate oxide layer and the bar-shaped silicon nitride layer. Performing a code implantation to form a plurality of coded memory cells using the photoresist layer as a mask. The photoresist layer is then removed. A polysilicon layer is further formed on the gate oxide layer and the bar-shaped silicon nitride layer. The polysilicon layer is back-etched until the bar-shaped silicon nitride layer is exposed. The silicon nitride layer is subsequently removed.