Influence of the Li and M (M = V, Nb, Ta, or Zr) Composition Ratio on the Piezoelectric Properties of LiM-doped AlN Films

This paper describes the piezoelectric properties of LiM-doped (M = V, Nb, Ta, or Zr) aluminum nitride ((LiyM1-y)xAl1-xN) films with respect to composition ratio Li and M. Films (LiyM1-y)xAl1-xN were prepared by a radio frequency magnetron sputtering method characterized crystal structure, as well electrical such coefficient d33 resistivity ρ. The for M Nb x 0.13-0.20 y 0.41-0.49 showed |d33| 8.26-9.54 pC/N, which 21-38% larger than non-doped AlN. On other hand, Zr exhibited decrease in piezoelectricity. against can be mainly explained combination following factors: crystallinity, lattice parameter c/a, ρ, orientation degree, polarity inversion. study revealed that gives different behaviors on physical similar stoichiometric compositions (y～0.5) are promising candidates materials micro-electro-mechanical systems.