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:
Jan. 16, 2001
Filed:
Nov. 17, 1998
Len-Yi Leu, Hsinchu, TW;
Winbond Electronics Corp., Hsinchu, TW;
Abstract
A method for fabricating split-gate flash memory cells is disclosed. In this method, the field oxide is formed after the formation of the poly-1 stripes, which eventually become the floating gates, by oxide growth, thus, the misalignment problems often encountered in the prior art processes between the floating gates and the field oxide layers are eliminated or at least minimized. The method also includes the step of forming a dummy CVD dielectric sidewall spacer with a predetermined thickness before the formation of the poly-2 layer, which eventually become the control gates; this greatly eliminates or at least minimizes the disparity in the peripheral control gate lengths between mirror (adjacent) cells. Both of these improvements can significantly contribute to the reduction of cell size without involving expensive upgrades in processing equipment.