Parametric study on the electro-optical performances of curved CMOS BSI image sensors

Abstract

Curved imaging sensors bring significant size, weight and cost reduction to imaging systems while mitigating offaxis optical aberrations, as opposed to current flat sensors. Unlocking these key features has captured the interest of major players over the last two decades. SILINA has been developing a CMOS Image Sensor (CIS) curving process, which adapts to various sensor characteristics. This enables to maximize the optical performance of every single imaging system. We have demonstrated the manufacturing of curved CMOS Front-Side Illuminated (FSI) and Back Side Illuminated (BSI), opening a new area of compact, fast, wide-angle and high-resolution optical lenses. An EMVA1288 compliant CMOS image sensor characterization testbeds has been developed in order to measure the electro-optical performances of curved CIS. Experimental data of dark current, photo-response nonuniformity, fixed pattern noise, quantum efficiency and more can be measured. In parallel to the electro-optical characterization campaign, reliability tests such as thermal tests (ageing, cycling) have been performed. This paper gives an overview of SILINA‘s main technological developments and electro-optical performance of CMOS Back Side Illuminated (BSI) curved image sensors is presented.