Recent advances of QWIP development in Sweden

The ongoing development of QWIP focal plane arrays at IRnova (formerly Acreo) has resulted in the launch of several new formats up to 640 by 512 pixels and the introduction of major improvements to all products. The achieved performance and imagery will be evaluated. In the light of the development of new formats, the results of hybridization a 640 by 512 detector with 20 µm pitch will be discussed. The driving forces behind these improvements have been the demands from both industrial applications where the requirements for the operating temperature are high due to the life time issues, and from space applications where the requirements for the quantum efficiency and dark current are extreme. For the latter type of applications a number of QWIPs covering the 4 to 20 µm wavelength band have been grown and evaluated. The demands for better performance are met by ongoing increases in light coupling, improvements of the quantum well structures, as well as fine tuning of the epitaxial growth parameters. This has led to FPAs that can operate at 75 K and operation close to 80 K is within reach. IRnova is also looking at other material systems to fulfill the requirements of next generation photon detectors.