Temperature dependence of piezoelectric properties for textured SBN ceramics

Temperature dependences of piezoelectric properties were studied for (001) textured ceramics of bismuth layer-structured ferroelectrics, SrBi₂Nb₂O₉ (SBN). The textured ceramics with varied orientation degrees were fabricated by templated, grain-growth method, and the temperature dependences of resonance frequency were estimated. Excellent temperature stability of resonance frequency was obtained for the 76% textured ceramics. The resonance frequency of the 76% textured specimens varied almost linearly over a wide temperature range. Therefore, the variation was slight, even in a high temperature region above 150degC. Temperature stability of a quartz crystal oscillator is generally higher than that of a ceramic resonator around room temperature. The variation of resonance frequency for the 76% textured SrBi₂Nb₂O₉ was larger than that of oscillation frequency for a typical quartz oscillator below 150degC also in this study. However, the variation of the textured SrBi₂Nb₂O₉ was smaller than that of the quartz oscillator over a wide temperature range from -50 to 250degC. Therefore, textured SrBi₂Nb₂O₉ ceramics is a major candidate material for the resonators used within a wide temperature range.