Numerical Analysis of a Very Long-Wavelength HgCdTe Pixel Array for Infrared Detection

In this paper we present numerical simulations of pixel arrays for detection of very long-wavelength (≥14 μm) infrared radiation. The drift-diffusion equations are solved on a three-dimensional finite element grid; this approach avoids errors typically introduced by one- or two-dimensional simplifications which are difficult to quantify. We simulate the device structure and compare our numerical results with values measured on fabricated and characterized devices. The aim is to test the quality of the HgCdTe material model and derive insights for geometry optimization of pixel array detectors grown by liquid-phase epitaxy.