Method for making a color image sensor with recessed contact apertures prior to thinning

• Main Author: POURQUIER ERIC
• Format: Patent
• Language: English
• Published: 10.02.2005
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION; SEMICONDUCTOR DEVICES

The invention relates to method for making a color image sensor. The method comprises: the formation, on the front face of a semiconductive wafer (10), of a series of active zones (ZA) comprising image detection circuits and each corresponding to a respective image sensor, each active zone being surrounded by input/output pads (22), the transfer of the wafer by its front face against the front face of a temporary supporting substrate (20), the elimination of the major part of the thickness of the silicon wafer, leaving a fine silicon layer (30) on the substrate, this fine silicon layer comprising the image detection circuits. Furthermore: firstly, layers of color filters (18) are deposited and then etched on the semiconductive layer thus thinned, secondly, prior to the transfer of the semiconductive wafer to the substrate, on the front face of the wafer, metallized apertures (25) are formed extending to a greater depth than the elements of the image detection circuits formed on the surface of the wafer, and the step of elimination of the major part of the thickness of the semiconductive wafer includes the baring, from the rear, of the metallization (22) of the metallized apertures.