Modeling and characterization of MTF at small pitch on Mercury Cadmium Telluride

Reduction of pixel pitch in infrared detector improves the spatial resolution and the range. The key performance of the detector range is the modulation transfer function (MTF). In an ideal case MTF can be express as the Fourier transformation of its square response. For small pixel, electrical lateral diffusion tends to reduce MTF from its ideal value. Computation shows that at 10μm the MTF is better than at 15μm for a given frequency. However, because of electric lateral diffusion, MTF at 10μm is more distant from its ideal value. Computations show that mesa can be used to have a better MTF.