Abstract: A PIN-FET combination having a basic layer, a first semiconductor layer as an absorption layer or, resepectively, a buffer layer, a second semiconductor layer as a contact layer or, respectively, as a channel layer and a third semiconductor layer as a cover layer grown surface-wide on a substrate. The p.sup.+ -region of the photodiode and, respectively, the gate region of the FET being fashioned therein. The basic layer is undoped or n-doped in the region of the photodiode and is p-doped in the region of the FET and a surface-wide, p-doped layer portion is present in the region of the FET between the channel layer and the substrate.