Detection of residual stress in Ba(Mg1/3Ta2/3)O3 thin films by nanoindentation technique

Abstract

In this paper, Ba(Mg1/3Ta2/3)O3 (BMT) thin films were prepared by an aqueous solution–gel method on the Pt/Ti/SiO2/Si(100) substrates with different annealing temperatures. The residual stress in the BMT thin films was investigated by nanoindentation technique. As the annealing temperature increases from 700°C to 800°C, the residual stress by nanoindentation technique in the BMT thin film increases from 418MPa to 475.9MPa, which is consistent with theoretical value ranged from 402.5MPa to 486.2MPa. Therefore, nanoindentation technique is an effective tool for detection of the residual stress in BMT thin films. Effect of residual stress on the dielectric properties of BMT thin films annealed at different temperatures was also studied. The increase in dielectric constant of BMT thin films annealed at 700°C and 750°C is larger than that of BMT thin films annealed at 750°C and 800°C due to the combined effect of the grain size and residual stress.