Method for producing a trench transistor and trench transistor

US7605032B2 · kind B2 · utility

Assignee

• Qimonda AG · DE

Inventors

• Richard Luyken · Munich, DE
• Hans-Peter Moll · Dresden, DE
• Martin Popp · Dresden, DE
• Till Schloesser · Dresden, DE
• Marc Strasser · Munich, DE
• Rolf Weis · Dresden, DE

Key dates

• Filing date: Sep 28, 2006
• Grant date: Oct 20, 2009
• Expiry date: Sep 28, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/027
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

In a method for producing a trench transistor, a substrate of a first conduction type is provided and a trench in the substrate and a gate dielectric in the trench are formed. A first conductive filling in the trench as a gate electrode on the gate dielectric and first source and drain regions are formed. An etched-back first conductive filling is produced by etching back the first conductive filling down to a depth below the first source and drain regions and second source and drain regions are formed. The second source and drain regions adjoin the first source and drain regions and extend to a depth at least as far as the etched-back first conductive filling. An insulation spacer above the etched-back first conductive filling is formed in the trench and a second conductive filling is provided in the trench as an upper part of the gate electrode.