Ytackumuleringskonstruktion för en strålningsdetektor

摘要

The detector comprises a substrate (300) of a first semiconductor material. At least one pixel (312-315) and a surface contact (310) have been formed on the first surface (301) and a layer (320) of a second semiconductor material has been formed on the second surface (302) of the substrate (300). A reverse bias voltage (350) is connected between the surface contact (310) and the at least one pixel (312-315) in order to create a depletion region (332) in the substrate (300). The work function of an n-type layer (320) must be smaller than the work function of the substrate (300) and the electron affinity of said layer (320) must be smaller than the electron affinity of the substrate (300). The work function of a p-type layer (320) must be bigger than the work function of the substrate (300) and the sum of the electron affinity and the band gap potential of said layer (320) must be bigger than the sum of the electron affinity and a band gap potential of the substrate (300).