Effect of Annealing Temperature on the Mechanical Properties of Bi3.15(Eu0.7Nd0.15)Ti3O12 Ferroelectric Thin Films

Bi3.15(Eu0.7Nd0.15)Ti3O12 (BENT) thin films were deposited on Pt/Ti/SiO2/Si(111) substrates via metal-organic decomposition (MOD) and annealed at 600 650 700 nd 750 The hardness and elastic modulus were measured by nanoindentation, and the residual stress was measured by X-ray diffraction (XRD). The grain sizes of the BENT thin films increase with the annealing temperatures increasing. With the grain size increasing from 37 nm to 46 nm, the hardness decreases from 8.4 GPa to 3.1 GPa and the elastic modulus decreases from 171.5 GPa to 141.6 GPa. While the annealing temperature increases from 600 o 750 the residual stress decreases from –743 MPa to –530 MPa. The BENT thin film annealed at 600 hows the largest hardness and elastic modulus.