  In this paper, we present the results of rigorous electromagnetic broadband
simulations applied to CMOS image sensors as well as experimental measurements.
We firstly compare the results of 1D, 2D, and 3D broadband simulations in the
visible range (380nm-720nm) of a 1.75$\mu$m CMOS image sensor, emphasizing the
limitations of 1D and 2D simulations and the need of 3D modeling, particularly
to rigorously simulate parameters like Quantum Efficiency. Then we illustrate
broadband simulations by two proposed solutions that improve the spectral
response of the sensor: an antireflective coating, and the reduction of the
optical stack. We finally show that results from experimental measurements are
in agreement with the simulated results.
