Synthesis and properties of dielectric Bi2(Zn1/3Nb2/3)2O7 thin films

Crystalline, Bi2(Zn1/3Nb2/3)2O7, BiZN thin films can be easily obtained when the films were in-situ deposited at high enough substrate temperature 450–600 °C (30 min). The optical parameters (N=n+ik) measured and analyzed by optical transmission spectroscopy are insensitive to the deposition parameters, provided that the films are crystalline. The dielectric properties converted from optical parameters are ε′=4.75 and Q=325. The dielectric constant of BiZN thin films in THz frequency regime, (ε′)f·THz=32, is markedly smaller than the ε′ value of BiZN bulk materials in microwave regime, and the quality factor of the thin films is less than 20% of the bulk materials. However, the dielectric constant of the thin films in THz region is still markedly larger than that derived from optical transmission spectroscopy in optical region.