Method for forming a back-side illuminated image sensor

US8436440B2 · kind B2 · utility

Assignees

• STMicroelectronics (Crolles 2) SAS · FR
• STMicroelectronics SA

Inventors

• Michel Marty · Buc, FR
• Francois Leverd · Meylan, FR

Key dates

• Filing date: Nov 9, 2010
• Grant date: May 7, 2013
• Expiry date: Jul 29, 2031

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F39/182

Abstract

A method for manufacturing a back-side illuminated image sensor, including the steps of: forming, inside and on top of an SOI-type silicon layer, components for trapping and transferring photogenerated carriers and isolation regions; forming a stack of interconnection levels on the silicon layer and attaching, on the interconnect stack, a semiconductor handle; removing the semiconductor support; forming, in the insulating layer and the silicon layer, trenches reaching the isolation regions; depositing a doped amorphous silicon layer, more heavily doped than the silicon layer, at least on the walls and the bottom of the trenches and having the amorphous silicon layer crystallize; and filling the trenches with a reflective material.