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:
Oct. 15, 2002
Filed:
Nov. 30, 2001
P R Chidambaram, Richardson, TX (US);
John A. Rodriguez, Richardson, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
According to one embodiment of the invention, a method of forming an asymmetric I/O transistor includes forming a first oxide layer outwardly from a semiconductor substrate, masking a first portion, less than a whole portion, of an I/O transistor region with a first photoresist layer, removing the first oxide layer from a core transistor region and a second portion of the I/O transistor region, removing the first photoresist layer, forming a second oxide layer outwardly from the substrate, forming gates for the core transistor region and the I/O transistor region, masking the first portion of the I/O transistor region with a second photoresist layer, doping a source region and a drain region of the core transistor region and a source region of the I/O transistor region with a first dopant, doping the source region and the drain region of the core transistor region and the source region of the I/O transistor region with a second dopant, removing the second photoresist layer, masking the core transistor region and the second portion of the I/O transistor region with a third photoresist layer, and doping a drain region of the I/O transistor region with a third dopant.