Power MOSFET device manufactured with simplified fabrication processes to achieve improved ruggedness and product cost savings

US5923065A · kind A · utility

Assignee

• MegaMOS Corporation · US

Inventors

• Koon Chong So · Fremont, US
• Danny Chi Nim · San Jose, US
• True-Lon Lin · Cupertino, US
• Fwu-Iuan Hshieh · Saratoga, US
• Yan Man Tsui · Union City, US

Key dates

• Filing date: Jun 12, 1996
• Grant date: Jul 13, 1999
• Expiry date: Jun 12, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/111

Abstract

This invention discloses a MOSFET device in a semiconductor chip with a top surface and a bottom surface. The MOSFET device includes a drain region, doped with impurities of a first conductivity type, formed in the semiconductor chip near the bottom surface. The MOSFET device further includes a vertical pn-junction region, which includes a lower-outer body region, doped with impurities of a second conductivity type, formed on top of the drain region. The pn-junction region further includes a source region, doped with impurities of the first conductivity type, formed on top of the lower-outer body region wherein the lower-outer body region defining a channel region extending from the source region to the drain region near the top surface. The MOSFET device further includes a gate formed on top of the channel region on the top surface. The gate includes a thin insulative bottom layer for insulating from the channel region. The gate is provided for applying a voltage thereon for controlling a current flowing from the source region to the drain region via the channel region. The MOSFET device further includes a deep heavily doped body-dopant region disposed immediately below the source…