3D modeling of CMOS image sensor and aperture size effect

Three-dimensional (3D) modeling is reported for CMOS active pixel image sensor with microlens and color filter layer. Process simulation is performed by Crosslight CSuprem while the optical effect is simulated by finite difference time domain technique and the electronic response by 3D drift-diffusion software APSYS. The opto-electronic responses are presented versus various power intensity and illumination wavelength. The aperture size of the isolated metal layer is also discussed. Whereas the microlens is shown to improve the sensitivity, the aperture size of the isolated metal layer should be optimized to avoid sensitivity loss. The presented results demonstrate a methodological and technical capability for 3D modeling optimization of complex CMOS image sensor.