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Zinc oxide is a II-VI semiconductor with a wide direct band gap of about 3.37 eV at
room temperature. Among the various growth techniques of 'Mn' doped ZnO thin films,
pulsed laser deposition (PLD) offers the advantages such as deposition at relatively high
oxygen pressure, high deposition rate and growth of highly oriented crystalline films at
low substrate temperature. The substitution of 'Mn' in ZnO host lattice affects the lattice
dynamics. Raman scattering provides a great deal of information in the optical modes of
vibrations at the center of Brillouin zone. The parameters of Raman mode such as
frequency, line width and lifetime provide the basic information of lattice dynamics. The
PLD grown films were analysed using x-ray diffraction (XRD), scanning electron
microscopy (SEM), UV-Vis-NIR spectroscopy and Raman spectroscopy. Good optical
quality of the films was confirmed from the transmittance of the film greater than 80% in
the visible region. The presence of non-polar E2high and E2low Raman modes in thin films
indicates that 'Mn' doping didn't change the wurtzite structure of ZnO. The intensity of
E2high mode and the peak position shifted towards the lower frequency with increase of
'Mn' concentration. Apart from the normal modes of ZnO the Zn1-xMnxO ceramic targets
shows two additional modes at 332 cm-1 (I2) and 524 cm-1 (I4). The modes I2 and I4 are
assigned as multi-phonon scattering considering the two phonon process in the disordered
lattice due to Mn doping.
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