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. 29, 2015
Filed:
Aug. 29, 2014
Texas Instruments Incorporated, Dallas, TX (US);
John Christopher Shriner, Allen, TX (US);
Abbas Ali, Plano, TX (US);
TEXAS INTRUMENTS INCORPORATED, Dallas, TX (US);
Abstract
A method of etching a ferroelectric capacitor stack structure including conductive upper and lower plates with a ferroelectric material, such as lead-zirconium-titanate (PZT), therebetween, with each of these layers defined by the same hard mask element. The stack etch process involves a plasma etch with a fluorine-bearing species as an active species in the etch of the conductive plates, and a non-fluorine-bearing chemistry for etching the PZT ferroelectric material. An example of the fluorine-bearing species is CF. Endpoint detection can be used to detect the point at which the upper plate etch reaches the PZT, at which point the gases in the chamber are purged to avoid etching the PZT material with fluorine. A steeper sidewall angle for the capacitor structure can be obtained.