Multilayer bispectral photodiode detector

Abstract

This bispectral detector comprises a plurality of unitary elements for detecting a first and a second electromagnetic radiation range, consisting of a stack of upper and lower semiconductor layers of a first conductivity type which are separated by an intermediate layer that forms a potential barrier between the upper and lower layers; and for each unitary detection element, two upper and lower semiconductor zones of a second conductivity type opposite to the first conductivity type, are arranged respectively so that they are in contact with the upper faces of the upper and lower layers so as to form PN junctions, the semiconductor zone being positioned, at least partially, in the bottom of an opening that passes through the upper and intermediate layers. The upper face of at least one of the upper and lower layers is entirely covered in a semiconductor layer of the second conductivity type. Cuts are made around each unitary detection element from the upper face of the stack and at least through the thickness of each semiconductor layer of the second conductivity type, entirely covering one or other of the upper and lower semiconductor layers of the first conductivity type, so as to form semiconductor zones of the second conductivity type.