Method of forming a trench using epitaxial lateral overgrowth and deep vertical trench structure

US9379196B2 · kind B2 · utility

Assignee

• Infineon Technologies Austria AG · AT

Inventors

• Ravi Keshav Joshi · Klagenfurt, AT
• Johannes Baumgartl · Arnoldstein, AT
• Martin Poelzl · Ossiach, AT
• Matthias Kuenle · Villach, AT
• Juergen Steinbrenner · Zistersdorf, AT
• Andreas Haghofer · Villach, AT
• Christoph Gruber · Wernberg, AT
• Georg Ehrentraut · Villach, AT

Key dates

• Filing date: Feb 6, 2014
• Grant date: Jun 28, 2016
• Expiry date: Feb 6, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/513
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

In one aspect, a method of forming a trench in a semiconductor material includes forming a first dielectric layer on a semiconductor substrate. The first dielectric layer includes first openings. An epitaxial layer is grown on the semiconductor substrate by an epitaxial lateral overgrowth process. The first openings are filled by the epitaxial layer and the epitaxial layer is grown onto adjacent portions of the first dielectric layer so that part of the first dielectric layer is uncovered by the epitaxial layer and a gap forms between opposing sidewalls of the epitaxial layer over the part of the first dielectric layer that is uncovered by the epitaxial layer. The gap defines a first trench in the epitaxial layer that extends to the first dielectric layer.