In the last years the fabrication of SPAD cameras has become one of the main fields of interest in 3-D imaging and bioapplications.
In this paper we present the comparison between two standard CMOS technologies to fabricate SPADs
cameras. The two technologies used in the comparison are a high voltage 0.35μm technology from AMS and a high
integration 130nm technology from STM. The advantage of using a standard CMOS technology among a dedicated is
the possibility of integrating the control/reading electronics into the same die. Neither of the processes is optimized for
optical applications, and no post-processing has been applied to improve the features.
The technologies have been selected due to the different integration density, and different intrinsic process parameters
with similar cost. Comparison has been done by fabricating several structures in both technologies which allow
analyzing sensibility, noise, and time response.
Experimental results show that the high voltage technology has a lower level of dark counts than the 130nm. Instead, the
high integration technology has a shorter quenching time, 1.5ns, which reduces the afterpulsing events to a negligible
level. In optical applications it is important to have a high integration of the camera reducing the pitch of the pixel, while
noise effects can be corrected in post-processing. For low frequency events, such as high energetic particle tracking, the
noise frequency has to be lower, but it is also required a high fill factor. Depending on the specific application this
analysis allows to opt for the most suitable technology.