Superlattice-based HOT MWIR imaging sensors

Purpose and goal

The aim of this project was to increase the operating temperature of IRnova´s infrared imaging sensors from 85 K to 130 K, which would enable us to use smaller coolers, resulting in small light-weight detectors. The target has been successfully achieved, since IRnova now has released a new light-weight sensor (Oden MW) with an operating temperature of 110 K, with a small and advanced cooler. By using a new fabrication method developed in this project we anticipate to further increase the operating temperature to at least 120 K.

Expected results and effects

Within the project we have developed a new fabrication method that significantly reduces the amount of parasitic leakage currents on the surfaces of the detector pixels in infrared imaging sensors. The anticipated effect of this is that the operating temperature of the sensor can be increased, which makes the detector even more competitive since the power consumption for cooling of the sensor can be further reduced.

Planned approach and implementation

The project has been performed in a joint effort between IRnova and Halmstad University, in which the partners´ expertise in the field have been combined in a fruitful way. In the project IRnova has been responsible for detector design and development of the fabrication process, while Halmstad University has evaluated different dielectric materials that are used to embed and protect the pixels in the sensor. Together we have gained better understanding of which process steps are affecting the surface leakage current the most, which is necessary to improve the detector performance.