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:
Dec. 19, 2000
Filed:
Dec. 16, 1997
Ruggero Castagnetti, San Jose, CA (US);
Yauh-Ching Liu, Sunnyvale, CA (US);
Gary Giust, Cupertino, CA (US);
Subramanian Ramesh, Cupertino, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
A method is provided for forming thin polysilicon transistor gates using dual doped polysilicon without reducing the ion implant energy. The method comprises depositing polysilicon over a region of a substrate, masking and implanting the polysilicon with dopant impurities to form the channel regions of one conductivity type, and removing the photo resist mask. The polysilicon layer is then masked to define the channel regions of the opposite conductivity type and is implanted with dopant impurities of the opposite conductivity type. Following the dual ion implantation, the photo resist mask is removed and the substrate may be annealed to activate the dopants in the polysilicon. The dual doped polysilicon layer is then polished using a chemical-mechanical polish to achieve a desired thickness for the polysilicon transistor gates. The polysilicon is subsequently masked and etched to define the polysilicon transistor gates.