Passivation structure for semiconductor devices

USRE49167E1 · kind E1 · reissue

Assignee

• Wolfspeed, Inc. · US

Inventors

• Van Mieczkowski · Apex, US
• Jonathan D. Young · Fuquay-Varina, US
• Qingchun Zhang · Cary, US
• John Williams Palmour · Raleigh, US

Key dates

• Filing date: Nov 12, 2019
• Grant date: Aug 9, 2022
• Expiry date: Nov 12, 2039

Classification

• Technology area (CPC —): General

Abstract

A Schottky diode is disclosed that includes a silicon carbide substrate, a silicon carbide drift layer, a Schottky contact, and a passivation structure. The silicon carbide drift layer provides an active region and an edge termination region about the active region. The Schottky contact has sides and a top extending between the two sides and includes a Schottky layer over the active region and an anode contact over the Schottky layer. The passivation structure covers the edge termination region, the sides of the Schottky contact, and at least a portion of the top of the Schottky contact. The passivation structure includes a first silicon nitride layer, a silicon dioxide layer over the first silicon nitride layer, and a second silicon nitride layer over the silicon dioxide layer.