Si-Based Ge 320 ✕ 256 Focal Plane Array for Short-Wave Infrared Imaging

Short wave infrared (SWIR) imaging has been used in various applications such as electronic board inspection, surveillance and gas detection. Unlike the conventional compound semiconductor focal plane array (FPA), in this work group IV back-illuminated imaging array with 320
$\times256$
pixels was demonstrated. For reference device with a diameter of 30
$\mu \text{m}$
, the dark current was 9.7 nA at 0 V. At 1550 nm, a responsivity of 0.61 A/W was obtained at −1 V using a Ge photodetector with a diameter of 75
$\mu \text{m}$
. The image of a halogen lamp was successfully captured at room temperature with a pixel operating bias of 0 V. Showing great compatibility with the existing CMOS technology, group IV imaging array becomes one of the promising candidates to be applied in SWIR imaging area.