1280×1024 8μm extended SWIR type-II superlattice detectors and camera at i3system

In this paper, we present the performance results of a 1280 × 1024 Type-II superlattice (T2SL)-based extended short wave infrared(eSWIR) 8μm pitch IR detector and the fabrication results of a camera utilizing Image Signal Processor(ISP)-based image processing. The developed Readout integrated circuit(ROIC) was fabricated using an Analog & Mixed-Signal 0.18um CMOS process. It is configured with a CTIA input structure for global shutter operation with a 1280×1024 resolution, 8μm pixel pitch, and features two gain modes : 168ke- and 50ke-. It supports a readout noise level of 46e- and a 60Hz frame rate. The fabricated IR detector was produced by hybrid bonding the T2SL focal plane array(FPA) to the ROIC, and its FPA temperature was cooled to 150K by integrating with a Rotary stirling cooler and an F/1.4 cold shield. The dimension of the detector integrated with the cooler is 143mm×71mm×57mm. The detection wavelength range is 0.9μm to 2.3μm. 150K operating conditions, the dark current density was measured to be less than 2.61×10^-9A/cm², the average quantum efficiency(QE) was 64.18%, and the detectivity was 3.87x10¹²cm∙Hz^1/2/W at 1.6um. The eSWIR band, compared to other IR bands, exhibits a large variation in incident energy (light) within changing scenes. Therefore, the camera requires an image processing technique that senses the incident energy and automatically sets the appropriate gain and integration time. This eSWIR camera was fabricated using gain and integration time-specific Non-Uniformity Correction (NUC) followed by ISP-based Auto Integration Control (AIC) and other image processing methods.