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:
Aug. 05, 2014
Filed:
Aug. 30, 2012
François Leverd, Saint Ismier, FR;
Laurent Favennec, Villard Bonnot, FR;
Arnaud Tournier, Grenoble, FR;
François Leverd, Saint Ismier, FR;
Laurent Favennec, Villard Bonnot, FR;
Arnaud Tournier, Grenoble, FR;
STMicroelectronics (Crolles 2) SAS, Crolles, FR;
Abstract
A method for producing a deep trench in a substrate includes a series of elementary etch cycles each etching a portion of the trench. Each elementary cycle includes deposition of a passivation layer on the sidewalls and the bottom of the trench portion etched during previous cycles; followed by pulsed plasma anisotropic ion etching of the trench portion etched during previous cycles, the etching; being implemented in an atmosphere comprising a passivating species; and including a first etch sequence followed by a second etch sequence of less power than the power of the first etch sequence. The first etch sequence etches the passivation layer deposited in the bottom of the portion so as to access the substrate and etches the free substrate at the bottom of the portion while leaving a passivation layer on sidewalls of the portion.