A detector element is disclosed with a semi-conductive converter element and metal contacts arranged thereon for at least one anode and at least one cathode, wherein at least one of the metal contacts comprises a contact layer made from a contact material based on precious metal and ruthenium as its mixed component. Moreover, an embodiment of the invention concerns a radiation detector with the detector element with a ruthenium-containing contact layer and, optionally, with an evaluation unit to read out a detector signal, as well as a medical device with the radiation detector. Furthermore, a method for the production of a detector element is described which includes the installation step of a contact material of at least one of the metal contacts on the converter element, wherein the contact material includes a precious metal base with ruthenium as its mixed component.