Planar sensor for neutron, X-ray or gamma radiation

摘要

A thin n-type layer (2) is deposited on a p-type wafer (1). A metallic deposit (7) on the etched passivated layer (4) provides the connection point for the pn-junction of the photodiode formed by the thin p-type layer and the n-type epitaxial layer (3). The thickness of this layer (3) determines the type of radiation to which the device is sensitive. The underside of the wafer (1) is etched to form a cavity (9) in which scintillation material is placed to form one pixel. Surrounding wafer material (8) and an aluminium reflecting layer (11) prevent radiation reaching adjacent pixels.