Backside illumination of CMOS image sensor

US6429036B1 · kind B1 · utility

Assignee

• Micron Technology, Inc. · US

Inventors

• Robert H. Nixon · Adelanto, US
• Nicholas Doudoumopoulos · Santa Monica, US
• Eric R. Fossum · La Cañada Flintridge, US

Key dates

• Filing date: Jan 14, 2000
• Grant date: Aug 6, 2002
• Expiry date: Jan 14, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2924/0002

Abstract

A CMOS image sensor die is fabricated and packaged to allow the light sensitive area of the die to be illuminated from either the front side or the backside, or both. The implementation is achieved using wafer level processing that facilitates photon collection at both surfaces. This approach permits processing apt the wafer level to allow the deposition of color filter arrays (CFA) on either surface. The silicon is thinned and the bump contacts and interconnect lines are relocated away from the image area of the die. The die is covered with an optically transparent material to provide additional support.