High-speed lateral polysilicon photodiode in standard CMOS technology

A high-performance lateral polysilicon photodiode was de-signed in standard 0.18 p m CMOS technology. The device has a frequency bandwidth far Cn the GHz range: the mea-sured bandwidth o / the poly photodiode was 6 GHz, which figure was limited by the measurement equipment. The high intrinsic (physical) bandwidth is due to a short excess car-rier lifetime. The eztenal (electrical) bandwidth is also high because of a v e q small parasitic capacitance (10.1 pR). This is the best bandwidth performance among all re-ported diodes designed in a standard CMOS. The quantum eficiency of this poly photodiode is 0.270 due to the very small light sensitive diode volume. The diode active area is limited b y a narrow depletion region and its depth b y the technology. I