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. 21, 2003
Filed:
Jan. 19, 2001
Sun-Chieh Chien, Hsin-Chu, TW;
Chien-Li Kuo, Hsin-Chu, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
The present invention provides a method for forming an embedded memory MOS. The method involves first forming a dielectric layer and an undoped polysilicon layer, respectively, on the surface of the semiconductor wafer with a defined memory array area and a periphery circuits region. Then, the undoped polysilicon layer in the memory array area is doped to become a doped polysilicon layer. Thereafter, a protective layer is formed on the surface of the semiconductor wafer, followed by a first photolithographic and etching process (PEP) to define a plurality of gate patterns in the protective layer in the memory array area. Then, a second PEP is applied to etch the undoped polysilicon layer in the periphery circuits region and the doped polysilicon layer in the memory array area to simultaneously form a gate of each MOS in the periphery circuits region and the memory array area. Finally, a lightly doped drain (LDD) of each MOS is formed, as well as a spacer and a source/drain (S/D) adjacent to each gate in the periphery circuits region.