Power trench MOSFET rectifier

US8581336B2 · kind B2 · utility

Inventors

• Tao Long · Shanghai, CN
• Yiming Wang · Beijing, CN
• Zhongyuan Jin · Shanghai, CN

Key dates

• Filing date: Jun 4, 2010
• Grant date: Nov 12, 2013
• Expiry date: Sep 16, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/126

Abstract

A trench MOSFET rectifier includes oxide layers having different thicknesses formed in different regions of the devices. The rectifying device also includes a source region of first conductivity type at a surface of each mesa region and a body region of a second conductivity type beneath each source region. The rectifying device also includes a dielectric layer lining the bottom and sidewall surfaces of the trenches, the portion of the dielectric layer on the bottom surface being thicker than the portion on the sidewall surface. A doped region underlies each of the first plurality of trenches. A polycrystalline silicon region filling each of the first plurality of trenches to form a gate region in each trench. A conductive material fills a plurality of contact trenches and forms ohmic contacts with the source region, body region, and gate region.