Design and Realization of a Novel Pixel Sensor for Color Imaging Applications in CMOS 90 nm Technology

Toward the complete integration of color sensors in CMOS technologies, a novel color sensitive device, the Transverse Field Detector, is proposed. The TFD color detection principle is based on the creation of a transverse, V-shaped electric field configuration in a Silicon active layer. The electric field is generated only by means of surface biasing/ collecting electrodes. Taking advantage on the dependence of the Silicon absorption length with respect to the incoming wavelength, each of the surface contacts collect photo-carriers down to a different depth. In this way three spectral functions are obtained at the three electrodes, without the use of any color filter. Newly developed pixel structures and a preliminary Active Pixel readout circuitry design are presented.