The challenge to design of a spaceborne image sensor

On behalf of ESA, Caeleste has developed the European Low Flux Image Sensor (Elfis). For step & stare operations we developed a new pixel with charge-domain global shutter (GS) together with LFoundry, Italy. This technology allows the combination of the GS operation with integrate-while-read (IWR) read-out, resulting in the maximum integration time for a given frame rate. Such a charge domain GS pixel has a very low dark current signal and hence a low dark current shot noise contribution.

The Elfis-sensor also uses correlated double sampling (CDS) to suppress the reset or kTC noise of the pixel. An in-pixel high dynamic range (HDR) operations completes the pixel design. By reading out alternatingly the ‘high gain’ and ‘low gain’ image, a dynamic range of more than 100 dB can be reached. The sensor will be used in a Backside Illuminated (BSI) configuration: after substrate removal a quantum efficiency of more than 90 percent can be achieved.

About the speaker

Jan Vermeiren graduated as electronics engineer at KU Leuven on a dissertation about speed measurements of traffic flows with CCD cameras in 1979. After having worked as a research assistant at KU Leuven, he joined Imec as team leader for CCD and CMOS infrared read-out circuit developments. Than he moved to OIP, where he was responsible for hyperspectral missions and for image intensified night vision equipment. In 2000 he was one of the founders of Xenics and responsible for the SWIR image sensor and camera developments. In 2015, he joined Caeleste as business development manager