Chemical Processing of Potassium‐Substituted Strontium Barium Niobate Thin Films through Metallo‐organics

Transparent and highly oriented K x (Sr 0.5 Ba 0.5 ) 1− x /2 Nb 2 O 6 ( x = 0.2, 0.4) (KSBN) thin films have been synthesized by a chemical solution deposition method. A homogeneous and stable KSBN precursor solution was prepared by controlling the reaction of metallo‐organics. K 0.4 Sr 0.4 Ba 0.4 Nb 2 O 6 ( x = 0.4, K 0.4 SBN50) and K 0.2 Sr 0.45 Ba 0.45 Nb 2 O 6 ( x = 0.2, K 0.2 SBN50) powders and thin films directly crystallized to the tetragonal tungsten bronze phase above 600°C. The thin films were crystallized on MgO(100) and Pt(100)/MgO(100) with c ‐axis preferred orientation. Two crystal lattice planes of K 0.4 SBN50 and K 0.2 SBN50 were intergrown at an orientation of 18.5° on MgO(100) and Pt(100)/MgO(100). K 0.4 SBN50 thin film on Pt(100)/MgO(100) showed the typical hysteresis loop ( P r = 22 µC/cm 2 , E c = 99 kV/cm at −190°C). The change in remnant polarization with temperature is strongly related to the diffuse phase transition of the epsilon‐ T curves.