Bolometers based on the structure of a superconductor - insulator - normal metal - insulator - superconductor with an absorber suspended above the substrate have been developed, manufactured, and experimentally investigated in the THz frequency range. In such structures, in contrast to the previously studied bolometers with an absorber located directly on the substrate, the bolometric mode of operation of the receiver is realized, i.e., more than one electron is excited per quantum of radiation (quantum efficiency greater than 1). In the studied bolometers, it was possible to achieve a quantum efficiency of 15 electrons per radiation quantum with a frequency of 350 GHz.