SWIR HgCdTe photodiodes for LADAR applications

The detection of infrared radiation is of great importance for many defense and civilian applications. Eyesafe short-wavelength infrared (SWIR) spectral range is particularly interesting due to atmospheric propagation through obscurants. Applications include low-cost, long-range target identification, identification of heavily obscured targets, obstacle avoidance, and high resolution imaging from a variety of platforms including hand-held devices, unmanned air vehicles, or ground vehicles. HgCdTe grown on CdTe/Si by molecular beam epitaxy (MBE) was processed into mini-arrays for 1.55 μm LADAR applications. Low-capacitance photodiodes (<10 pF) were demonstrated at room temperature with frequency responses exceeding 100 MHz. This paper discusses the device architecture and device performance results.