Single mask process for manufacture of fast recovery diode

US6294445A · kind A · utility

Assignee

• International Rectifier Corporation · US

Inventors

• Igor Bol · West Hollywood, US
• Iftikhar Ahmed · Singapore, SG

Key dates

• Filing date: Feb 22, 2000
• Grant date: Sep 25, 2001
• Expiry date: Feb 22, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D8/60

Abstract

A single mask process for manufacture of a FRED employs a thick oxide layer over an N type silicon surface and a thin nitride layer over the oxide. A single mask defines FRED device spaced P diffusions. The oxide spanning the P diffusions is laterally etched away, under the nitride layer to expose the surface of adjacent P diffusions and the spanning N type silicon surface. All nitride is then removed and a top contact layer of aluminum is applied atop the silicon surface, contacting a P guard ring diffusion; the surface of the P diffusions defining PN junctions; and the top of the N silicon to define a Schottky diode contact.