Integration Aspects of the Implementation of Through Silicon Vias (TSV) for CMOS Image Sensors

One of the first device types to benefit from TSV implementation is the CMOS image sensor, an image capture device designed to combine high image quality within a compact form-factor that can be mass produced at low cost. End markets include mobile phones, PDAs and gaming consoles. STMicroelectronics is pioneering their production, based on ≤65nm CMOS technology, at its 300mm facility in Crolles. These sensors employ TSVs as part of a wafer level package allowing the camera module to be directly soldered to a phone PCB thereby saving cost, space and time to manufacture. SPTS's Versalis fxP system is being used to combine multiple TSV formation processes onto one platform including hard-mask deposition, hard-mask etching, TSV etching, partial PMD etching, dielectric liner deposition and spacer etching to define the area for the metal contact. All processes are carried out on a silicon wafer bonded to a glass carrier, through which the final device is illuminated. We will present a TSV silicon etch process ...