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In this work, ternary relaxor ferroelectric thin films 0.5mol% Mn‐doped 0.36Pb(In1/2Nb1/2)O3‐0.36Pb(Mg1/3Nb2/3)O3‐0.28PbTiO3 (Mn‐PIMNT) with high Curie point were grown on the Pt/Ti/SiO2/Si substrate with the addition of La0.6Sr0.4CoO3 (LSCO) as a buffer layer. The phase and domain structure, nanoscale piezoelectric response, and macroscopic ferroelectric, dielectric, pyroelectric properties of Mn‐PIMNT thin films were studied. Both the crystalline quality and the crystallographic orientation exhibited strong temperature dependence within the substrate temperature of 450–580°C. Under the optimized temperature of 530°C, the Mn‐PIMNT thin film exhibited excellent global electrical properties with remnant polarization Pr∼35.6 μC/cm2, coercive field Ec∼5.1 kV/mm, dielectric constant εr${\varepsilon _r}$∼3360, and relatively low dielectric loss tanδ∼0.03. It was further found that the pyroelectric coefficient of the Si‐substrated Mn‐PIMNT thin film reached 6.7 × 10−4 C/m2·K. The optimized ferroelectric thin films Mn‐PIMNT on Si substrate with excellent temperature stability show great potential in integrated microelectromechanical systems.

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In this study, ternary ferroelectric 0.06Pb(Mn1/3Nb2/3)O3–0.94Pb(Zr0.48Ti0.52)O3 (PMN–PZT) thin film with high piezoelectric coefficient were grown on La0.6Sr0.4CoO3‐buffered Pt/Ti/SiO2/Si substrate by RF magnetron sputtering method. The phase and domain structure along with the macroscopic electrical properties were obtained. Under the optimized temperature of 550°C and sputtering pressure 0.9 Pa, the PMN–PZT film owned large remnant ferroelectric polarization of 62 μC/cm2. In addition, the PMN–PZT film had polydomain structures with fingerprint‐type nanosized domain patterns and typical local piezoelectric response. Through piezoelectric force microscopy, the PMN–PZT thin film at nanoscale exhibited obvious domain reversal when subjected to in situ poling field. It was further found that the quasi‐static piezoelectric coefficient of the PMN–PZT thin film reached 267 pC/N, which was about twice to that of the commercial PbZrO3–PbTiO3 (PZT) thin film. The optimized relaxor ferroelectric thin film PMN–PZT on silicon with global electrical properties shows great potential in the piezoelectric micro‐electro‐mechanical systems applications.

In this paper, we theoretically and experimentally reported a lead‐free pyroelectric infrared (PIR) detector using (Bi1/2Na1/2TiO3)‐BaTiO3(BNT‐BT) ferroelectric ceramics as the sensitive material. The variation of noise density, voltage response rate (RV), and specific detection rate (D*) with the modulation frequency under the current mode amplification circuit was investigated, and it was found that the lead‐free PIR detector showed high RV in the low frequency band. The RV and D* reached 1.51 × 105 V/W and 2.02 × 108 cmHz1/2W−1 at 10 Hz, respectively. The results were much superior to the PIR based on traditional commercial pyroelectric ceramics, indicating that BNT‐BT lead‐free ceramics have great potential in application to PIR detectors.