Toshiba has launched a 1.12µm pixel CMOS image sensor that offers a small-level pixel size with enhanced sensitivity and imaging performance of BSI (back-side illumination) technology. As smartphones get smaller and their image sensors offer 5 to 8M pixels, there is a challenge to develop smaller pixels. However, miniaturisation of pixels can result in a fall in performance. BSI overcomes this problem and delivers good response levels to CMOS imaging. BSI sensors deploy lenses on its silicon substrate, which is present on the rear of the sensor and not on the front, where wiring limits light absorption. This positioning boosts light sensitivity and absorption, and allows formation of finer image pixels in small CMOS image sensors. The company used BSI to realise image pixels with a pitch of 1.12μm and also to pack 8.08 million of image pixels into a 1/4inch sensor. The sensor attains high level imaging and processing to bring high image quality to smartphones. The company expects BSI CMOS image sensors to become the mainstream technology in portable digital technology, with applications expanding from mobile phones and digital cameras to smartphones and tablets.
