Integrated power device on a semiconductor substrate having an improved trench gate structure

US9520468B2 · kind B2 · utility

Assignee

• STMicroelectronics SA

Inventors

• Angelo Magri · Mascalucia, IT
• Antonino Alessandria · Catania, IT
• Stefania Fortuna
• Leonardo Fragapane · Catania, IT

Key dates

• Filing date: Jan 28, 2014
• Grant date: Dec 13, 2016
• Expiry date: Feb 24, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/664

Abstract

A power device integrated on a semiconductor substrate and having a plurality of conductive bridges within a trench gate structure. In an embodiment, a semiconductor substrate includes a trench having sidewalls and a bottom, the walls and bottom are covered with a first insulating coating layer which then also includes a conductive gate structure. An embodiment provides the formation of the conductive gate structure with covering at least the sidewalls with a second conductive coating layer of a first conductive material. This results in a conductive central region of a second conductive material having a different resistivity than the first conductive material forming a plurality of conductive bridges between said second conductive coating layer and said conductive central region.