Acoustic Properties of β-In₂S₃ Thin Films Prepared by Spray

Abstract

β-In 2 S 3 thin films have been prepared on pyrex glass substrates by the spray pyrolysis technique at 340°C. We have analyzed by acoustic microscopy and particularly by acoustic signature V ( z ) these films with various thickness (0.3–2.5 µm). The acoustic signature, performed at 130 and 570 MHz allows us to reach elastic properties of β-In 2 S 3 material and especially Young's modulus. Its value (443 GPa) is of the same order of those of ceramics. Besides elastic properties and using scanning electron microscopy (SEM) and atomic force microscopy (AFM) investigations, we have shown that the V ( z ) signature gives valuable information about the defects in the material. Finally, the experimental results have been discussed related to the dispersion curves of velocity of the first mode of β-In 2 S 3 /pyrex system.