With the development of infrared focal plane technology, large-area infrared focal plane devices have been widely used in remote sensing, meteorology, resource surveys and high-resolution earth observation satellites. Therefore, based on the third-generation infrared focal plane technology ultra-large-scale focal plane devices are called research hotspots at home and abroad. The short wave (SW) 2 k (18 μm, pixel pitch) mercury cadmium telluride(MCT) infrared focal plane device was reported, which was successfully developed by Kunming Institute of Physics using n-on-p technology. The SW 2 k MCT infrared focal plane device has broken through the preparation of large-size cadmium zinc telluride (CdZnTe) substrates and the growth of large-area liquid phase epitaxy thin film materials. The substrate size was increased from Φ75 mm to Φ90 mm, and a highly uniform large-area Mercury Cadmium Telluride (HgCdTe) thin film material was obtained. By tackling key technologies such as large array device technology and large area array flip-chip interconnect, a high-performance SW 2 k×2 k (18 μm) MCT infrared focal plane device with an operability over 99.9%, average peak detection rate (D*) greater than 4×10¹² (cm·Hz^1/2)/W and dark current density of 1 nA/cm² was finally obtained.