Low-Noise Avalanche Photodiode With Graded Junction in 0.15- \mum CMOS Technology.

This letter presents the experimental characterization and noise modeling of a CMOS avalanche photodiode with pwell/n-iso active junction fabricated in a 0.15- \mum standard CMOS process. The device exhibits a remarkably low excess noise factor F=6 at a gain M={50} in the blue spectral region, and F={12}$ at M={50} in the near-infrared. Gain and noise characteristics are accurately predicted using Hayat dead-space model applied to a linearly graded junction doping profile. [ABSTRACT FROM AUTHOR]