Abstract <p>New technologies have been developed for the production of superconductor–insulator–normal metal–insulator–superconductor (SINIS) structures made of Nb, NbN, and Al, which serve as sensitive elements for radiation receivers in the terahertz and subterahertz ranges. Two-stage fabrication technology by selective etching of niobium and modernized fabfication technology by dry selective etching and anodization of niobium with an additional sacrificial layer of SiO₂ made it possible to create structures with narrow absorbers made of normal metal with a width of less than 10 µm. The fabricated structures have characteristics close to those theoretically expected. The results of the work can be used for the development and fabrication of ultra-sensitive detectors for terahertz and subterahertz ranges with operating temperatures from 1.5 to 9.0 K using optical photolithography methods, which allows their use in more accessible cryogenic systems than He³–He⁴ dissolution cryostats, which are used in work with classical SINIS structures with operating temperatures in the range of 100–300 mK, where Al is a superconductor.</p>