METHOD OF ANALYSIS OF THIN SURFACE LAYERS BY MOSSBAUER EFFECT

A method for investigation of the surface layers composition and structure is described. The conversion electrons emitted after recoilles absorption of gamma-rays are used. The conversion electron energy depends on the thickness of the layer the electrons pass across. That is why the obtained Mössbauer spectra with electrons coming from different depths characterize the layers these electrons have been formed in. The conversion electrons are focused by a small iron-free beta-spectrometer with corrected field shape. The investigations are made using the nuclide 119Sn. The possibilities of the method are illustrated with a tin surface treated over bromine vapours. The Mössbauer spectra with electrons from three different depths are shown. The spectra of a tin surface treated over fumic nitric acid are also investigated. For the SnO2-layer, differs the observed relation between the experimental effect, ε%, and the electron energy at room temperature and at liquid nitrogen temperature greatly. © 1969.