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Abstract??Spectral dependences of the transmittance of the IC-protecting multilayer dielectric coating are theoretically and experimentally studied to facilitate the development and design of CMOS color area imagers. The results obtained demonstrate the modulation of the spectral sensitivity of photodiodes with conventional multilayer dielectric coatings, a characteristic that substantially impedes color separation of a photosignal. Numerical simulation of the spectral transparency of the conventional dielectric coating employed indicates that interference in the upper dielectric layer whose refractive index appears significantly higher than the tabulated value plays the main role. A brief review of the methods for correction of the undesirable features of the spectral transparency that are caused by the maximum possible refractive index of an Si3N4protective coating are reviewed.

Abstract??The spectral photosensitivity ofn+-psilicon photodiodes with ap+layer implanted in the substrate is studied experimentally. It is demonstrated that suchp+doping effectively shifts the long-wavelength edge of the photosensitivity in the optical spectral range and the shift depends on the depth of thep+layer. A new concept for creating selectively sensitive photocells for megapixel color-image receivers is proposed. The receivers are based onn+-pphotodiode structures containing a few layers that are implanted at different depths and form desired color-separating potential barriers and lateral diffusion channels for collection of the minority carriers generated by photons of different colors.