LDMOS device with isolation guard rings

US6924531B2 · kind B2 · utility

Assignee

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD. · TW

Inventors

• Fu-Hsin Chen · Hsinchu, TW
• Ruey-Hsin Liu · Baoshan, TW

Key dates

• Filing date: Oct 1, 2003
• Grant date: Aug 2, 2005
• Expiry date: Oct 24, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/378

Abstract

A method of forming a LDMOS semiconductor device and structure for same. A preferred embodiment comprises forming a first guard ring around and proximate the drain of a LDMOS device, and forming a second guard ring around the first guard ring. The first guard ring comprises a P+ base guard ring, and the second guard ring comprises an N+ collector guard ring formed in a deep N-well, in one embodiment. The first guard ring and second guard ring prevent leakage current from flowing from the drain of the LDMOS device to the substrate.