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:
Jul. 05, 1983
Filed:
Dec. 22, 1980
Robert F Pfeifer, Centerville, OH (US);
Murray L Trudel, Centerville, OH (US);
NCR Corporation, Dayton, OH (US);
Abstract
Disclosed is a process for a CMOS integrated circuit having polysilicon conductors of a single conductivity, single impurity type. After forming the conductors they are covered by an oxidation and diffusion mask consisting of a dual layer of silicon dioxide and silicon nitride. Then, source and drains of the p-channel and n-channel transistors are formed. Next, an implantation or diffusion barrier is grown over sources and drains. The oxidation and diffusion mask over all the conductors is then removed and they are all doped simultaneously using a single type impurity. The process may be used to additionally form polysilicon resistors by initially doping the polysilicon to a low level of conductivity. After forming the conductors and resistors they are covered by the oxidation and diffusion mask. Then a resistor mask of either silicon nitride or polysilicon is formed over the resistors to protect them during the high conductivity doping of the conductors.