The present invention relates to a semiconductor hetereostructure radiation detector for wavelengths in the infrared spectral range. The semiconductor heterostructure radiation detector is provided with an active layer composed of a multiplicity of periodically recurring single-layer systems each provided with a potential well structure having at least one quantum well with subbands (quantum well), the so-called excitation zone, which is connected on one side to a tunnel barrier zone, whose potential adjacent to the excitation zone is higher than the band-edge energy of a drift zone adjoining on the other side of the potential-well structure. The invention is characterized in that said drift zone is adjacent to a trap zone which is provided with at least one quantum-well structure containing subbands and is connected to the tunnel barrier zone of another single-layer system immediately adjacent in periodic sequence comprising an excitation zone, a drift zone, trap zone and a tunnel barrier zone, that the energy levels of said subbands of said quantum-well structures inside said excitation zone and said trap zone as well as the thickness of said tunnel barrier zone are set in such a manner that there is sufficient tunneling probability for the charge carriers to tunnel from the trap zone through the tunnel barrier zone into the excitation zone.