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. 06, 2001
Filed:
Jun. 28, 1999
Jui-Tsen Huang, Taipei, TW;
Kuang-Hua Shih, Hsin-Chu, TW;
Tsu-An Lin, Hsin-Chu Hsien, TW;
Chan-Lon Yang, Taipei, TW;
United Microelectronics Corp., Hsin-Chu, TW;
Abstract
The present invention provides a method for etching a poly-silicon layer of a semiconductor wafer. The semiconductor wafer comprises a dielectric layer, a poly-silicon layer situated on the dielectric layer and containing dopants to a predetermined depth, and a photo-resist layer having a rectangular cross-section above a predetermined area of the poly-silicon layer. The semiconductor wafer is processed in a plasma chamber. A first dry-etching process is performed to vertically etch away the dopant-containing portion of the poly-silicon layer not covered by the photo-resist layer. Then, a second dry-etching process is performed to vertically etch away the residual portion of the poly-silicon layer not covered by the photo-resist layer down to the surface of the dielectric layer. The etching gases used in the first dry-etching process differ from those used in the second dry-etching process, and the main etching gas of the first dry-etching process is C,F,.