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:
Feb. 01, 2000
Filed:
Dec. 22, 1997
Jyh-Cheng You, I-Lan, TW;
Pei-Hung Chen, Hsin-Chu, TW;
Shau-Tsung Yu, Taipei, TW;
Yi-Jing Chu, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Company, Hsin-Chu, TW;
Abstract
The present invention provides a method of manufacturing a read only memory that is code implanted late in the process after the first level metal thus reducing the turn around time to ship a customer order. The invention comprising the steps of: forming bit lines 125 and word lines 160 in a cell area 12A and MOS transistors in a peripheral area 13 of an integrated circuit; forming a first dielectric layer 300 over the surface; etching back the first dielectric layer 300 in the cell area; forming metal contacts 700 to the MOS devices in the peripheral areas 13; forming the second dielectric layer 320 over the resultant surface, storing the integrated circuit; and programming the ROM region 12A by the steps of forming a Code mask 340 with openings 340A from over portions of word lines in the cell area and implanting impurities through the openings 340A into substrate under the selected word lines 160 thereby programming the ROM device.