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:
Jun. 05, 2001
Filed:
Jun. 01, 2000
Chien-Hsing Lee, Chu-Pei, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
A semiconductor wafer includes a silicon substrate, at least two floating gates positioned on the silicon substrate and a silicon nitride layer positioned on the surface of each floating gate. The method first uses a lithographic process and an ion implantation process to form a drain in the silicon substrate between the two floating gates. A passivation layer is then formed uniformly on the surface of the silicon substrate and the top surface and the sides of the floating gate. An etching process is performed later to form a spacer around each floating gate, the spacers between the floating gate are joined and cover the drain. Finally, an ion implantation process is performed, using the spacers as a hard mask, to form a source in the silicon substrate.