Acoustic properties of beta-In2S3 thin films prepared by spray

beta-In2S3 thin films have been prepared on pyrex glass substrates by the s pray prolysis technique at 340 degrees C; We have analyzed by acoustic micr oscopy and particularly by acoustic signature V(z) these films with various thickness (0.3-2.5 mu m). The acoustic signature, performed at 130 and 570 MHz allows us to reach elastic properties of beta-In(2)s(3) material and e specially Young's modulus. Its value (443 GPa) is of the same order of thos e of ceramics. Besides elastic properties and using scanning electron micro scopy (SEM) and atomic force microscopy (AFM) investigations, we have shown that the V(z) signature gives valuable information about the defects in th e material. Finally, the experimental results have been discussed related t o the dispersion curves of velocity of the first mode of beta-In2S3/pyrex s ystem.