A new superlattice in semiconductors is discussed which allows to determine the geometrical stability and precision of delta-doping layers in respect to migration and diffusion effects, and even a technological evaluation of the production devíce. This structure acts as inner probe in doping superlattices quite as the known case of enlarged wells in composition superlattices does. Donor - acceptor - pair luminescence radiation is used, which in its dependence on the pair separation distance reflects the geometrical arrangement of neighboring delta­ doped layers provided both donors and acceptors are present in each sheet.