Surface passivation to reduce dark current in a CMOS image sensor

US6909162B2 · kind B2 · utility

Assignee

• OmniVision Technologies, Inc. · US

Inventors

• Chih-huei Wu · Sunnyvale, US
• Tiemin Zhao · Palo Alto, US
• Xinping He · San Jose, US

Key dates

• Filing date: Nov 2, 2001
• Grant date: Jun 21, 2005
• Expiry date: Sep 9, 2023

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/547

Abstract

A method for reducing dark current in a photodiode is disclosed. The photodiode comprises a N-well formed in a P-substrate. The method comprises doping the surface of said N-well with a nitrogen dopant. Alternatively, an oxygen or silicon dopant may be used. Still alternatively, a silicon oxynitride layer may be formed over the N-well.