IDENTIFICATION AND QUANTIFICATION OF SILICON POLYMORPHISM IN MAGNETRON SPUTTERED THIN FILMS

he article raises the problem of disagreements between different approaches to studying silicon polymorphism in silicon nanofilms using Raman spectroscopy. Here, the polymorphism assessment was carried out using a Horiba brand device Jobin – Yvon HR 800 UV (France). An argon-cadmium laser with a wavelength of 315 nm was used as the excitation source. The measurements were carried out in the range from 0 to 3200 cm-1. Two different types of film were studied. Parallel measurements of Raman spectra revealed the homogeneity of the polymorphic composition of films of both types, which indicates the advantage of magnetron sputtering technology over the CVD method in this part. The analysis revealed: a split peak with a maximum in the region of 120 cm-1 interpreted as a manifestation of amorphous silicon, a peak in the region of 210 cm-1 attributed to the crystalline form of silicon. Peaks were found in the region of 408 and 520 cm-1, which can be assessed as signs of nanosilicon. Also, in the spectrogram there are peaks in the range of 600-660 cm-1 (presumably copper silicide, an intermediate layer between the substrate and the film), as well as peaks at 900-1000 cm-1 and 1500-1660 cm-1, identified as manifestations of copper. It was found that in the case of silicon film with an amorphous and crystalline structure, a laser wavelength of 315 nm is sufficient for the beam to penetrate the substrate and intermediate layers and record their spectrum. In this case, the copper of the substrate is identified by a peak in the region of 1500-1660 cm-1. The nanocrystalline structure is less permeable and the identification peak of copper in this case is in the region of 900-1000 cm-1. To the greatest extent, the results obtained correlate with the results obtained by Levitsky V.S. It is recommended to use his approaches to the identification of silicon films, as they most adequately describe the relationship between the results of Raman spectrometry and the polymorphism of silicon films.