High-speed bipolar phototransistors in a 180Â nm CMOS process

► We present four types of high-speed optimized pnp bipolar phototransistors built in a standard 180 nm CMOS process. ► For achieving high bandwidths the phototransistors were implemented with a thick low doped intrinsic layer between base and collector. ► Optical characterisations were done at 410, 675 and 850 nm. ► The presented phototransistors achieve bandwidths up to 92 MHz and dynamic responsivities up to 2.95 A/W.