Semiconductor device and method of manufacturing the same

US9837530B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Stefan Decker · Munich, DE
• Sven Lanzerstorfer · Feldkirchen in Kärnten, AT
• Thorsten Meyer · Regensburg, DE
• Robert Zink · Hagen, DE

Key dates

• Filing date: Sep 29, 2015
• Grant date: Dec 5, 2017
• Expiry date: Sep 29, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/256

Abstract

A semiconductor device comprises a semiconductor body. The semiconductor body comprises insulated gate field effect transistor cells. At least one of the insulated gate field effect transistor cells comprises a source zone of a first conductivity type, a body zone of a second, complementary conductivity type, a drift zone of the first conductivity type, and a trench gate structure extending into the semiconductor body through the body zone along a vertical direction. The trench gate structure comprises a gate electrode separated from the semiconductor body by a trench dielectric. The trench dielectric comprises a source dielectric part interposed between the gate electrode and the source zone and a gate dielectric part interposed between the gate electrode and the body zone. The ratio of a maximum thickness of the source dielectric part along a lateral direction and the minimum thickness of the gate dielectric part along the lateral direction is at least 1.5.