Two-dimensional CMOS image sensor characterization

In this work two-dimensional (2-D) measurements obtained by the unique submicron scanning system (S-cube system) for the industrial graded CMOS image sensor (CIS) are presented. Full 2-D point spread function (PSF) extracted for several CIS sub arrays via sub-micron spot light stimulation is used for full sensor characterization; including crosstalk (CTK) generation phenomena, its dependence on the array topology and the "neighborhood" condition, along with a 2-D pixel MTF calculated from the PSF measurements. The degradation of the imager performance caused by the diffusion effects is apparent from the calculated MTF. The effectiveness and advantages of the proposed method are shown; enabling both to determine the influence of each pixel-composing element on its overall signal, along with sensor resolution abilities characterization for each wavelength of interest. The advantages and necessities of 2D-characterization for sensor performance understanding and improvement are clearly emphasized