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. 26, 2002
Filed:
May. 24, 2000
Helmut Horst Tews, Poughkeepsie, NY (US);
Alexander Michaelis, Dormagen, DE;
Stephan Kudelka, Fishkill, NY (US);
Uwe Schroeder, Fishkill, NY (US);
Ulrike Gruening, Munich, DE;
Infineon Technologies AG, Munich, DE;
Abstract
A method of using at least two insulative layers to form the isolation collar of a trench device, and the device formed therefrom. The first layer is preferably an oxide (e.g., silicon dioxide ) formed on the trench substrate sidewalls, and is formed through a TEOS, LOCOS, or combined TEOS/LOCOS process. Preferably, both the TEOS process and the LOCOS process are used to form the first layer. The second layer is preferably a silicon nitride layer ( ) formed on the oxide layer. The multiple layers function as an isolation collar stack for the trench. The dopant penetration barrier properties of the second layer permit the dielectric collar stack to be used as a self aligned mask for subsequent buried plate ( ) doping.