Micro-Raman analysis of BiSrCaCuO superconducting thin films deposited by pulsed laser evaporation

Abstract Micro-Raman spectra of Bi Sr Ca Cu O superconducting thin films have been recorded at RT by using a multichannel spectrometer. Two films with different grain morphology have been investigated. For mica like crystals Raman bands at 294, 468 and 625 cm −1 are found to be characteristic of the 2212 phase in agreement with RBS analysis and X-ray diffraction. On the other hand, needle like crystals exhibit a broad feature between 520 cm −1 and 580 cm −1 the peak of which being located at ∼ 556 cm −1 . These experiments evidence clearly the presence of two distinct in the films with one being superconducting at 83K.