Electrostatic discharge protection device and method therefore

US7164566B2 · kind B2 · utility

Assignee

• Freeescale Semiconductor, Inc. · US

Inventors

• Hongzhong Xu · Gilbert, US
• Beth Baumert · Scottsdale, US
• Richard T. Ida · Chandler, US

Key dates

• Filing date: Mar 19, 2004
• Grant date: Jan 16, 2007
• Expiry date: Feb 4, 2025

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D10/421

Abstract

Methods and apparatus are provided an electrostatic discharge (ESD) protection device having a first terminal and a second terminal. The ESD protection device comprises a vertical transistor having a collector coupled to the first terminal, a base, and an emitter coupled to the second terminal. A zener diode has a first terminal coupled to the first terminal of the ESD protection device and a second terminal coupled to the base of the vertical transistor. Subsurface current paths are provided to redistribute current from a surface of the vertical transistor in an ESD event. The method comprises generating an ionization current when a zener diode breaks down during an ESD event. The ionization current density from a surface zener diode region is reduced. The ionization current enables a transistor to dissipate the ESD event.