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:
Nov. 21, 1995
Filed:
Apr. 29, 1993
Applicant:
Inventor:
Richard A Chapman, Dallas, TX (US);
Assignee:
Texas Instruments Incorporated, Dallas, TX (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 44 ; 437 27 ; 437 34 ; 437 56 ; 437 57 ; 437 58 ; 437152 ; 257369 ; 257408 ;
Abstract
A semiconductor device having high and low voltage transistors on the same chip. High voltage NMOS transistor 76 comprises a polysilicon gate 40 doped at a first dopant level. Low voltage NMOS transistor comprises a polysilicon gate 44 doped at a second dopant level. The second dopant level is higher than the first. High voltage PMOS transistor 84 comprises a polysilicon gate 48 doped at a third dopant level. Low voltage PMOS transistor comprises a polysilicon gate 52 doped at a fourth dopant level. The fourth dopant level is higher than the third.