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:
Feb. 01, 2005
Filed:
Sep. 25, 2003
William J. Taylor, Jr., Round Rock, TX (US);
Cesar M. Garza, Round Rock, TX (US);
William J. Taylor, Jr., Round Rock, TX (US);
Cesar M. Garza, Round Rock, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A semiconductor process and structure () uses a disposable sidewall spacer () associated with lightly doped drain (LDD) transistors. The disposable sidewall spacers are efficiently removed by a gaseous fluorine ambient. Either molecular or atomic fluorine gas is used to remove a silicon germanium sidewall spacer with high selectivity to exposed insulating layers. This etch process is also isotropic. An additional benefit of using a gaseous fluorine ambient is incorporation of fluorine in isolation regions () surrounding the transistors, thereby reducing the dielectric constant. Improved insulating properties of the isolations regions can allow increased integration.