Radiation active pixel sensor integrated in 0.25 gm cmos technology: A perspective analysis

Integrated CMOS sensors are being widely applied in several fields; recently they have been proposed as ionizing particle detectors with attractive features, such as high sensitivity and spatial resolution. Mostly interesting, CMOS processing makes it possible to integrate on the same chip physical sensors and state-of-the-art signal-processing circuitry. In this paper, we discuss the potential implementation of radiation detectors based on an active pixel scheme: by means of simulation studies, technological options have been compared, looking for optimal overall performance of the sensing system. In particular, two commercially available, 0.25 mu m CMOS technologies (namely, UMC D1P5M and IBM 6FS) have been considered. Mixed-mode (device/circuit) analyses have been carried out by using the ISE-TCAD package; the transient response to a particle hit has been predicted and correlated to major design parameters and to environmental conditions. The obtained results suggest that innovative detectors, featuring high resolution and noise immunity can be fabricated by using standard CMOS technology.