Ferroelectric ceramics, electronic component and manufacturing method of ferroelectric ceramics

Ferroelectric ceramics comprising:

• a foundation film;
• a Pb(Zr1-ATiA)O3 film formed on the foundation film;
• a Pb(Zr1-BTiB)O3 seed crystal film formed, by sputtering, on the Pb(Zr1-ATiA)O3 film;
• and
• a Pb(Zr1-xTix)O3 crystal film formed on the Pb(Zr1-BTiB)O3 seed crystal film, wherein:
• the foundation film is a Pt film oriented to (100), or the foundation film is a double-layer film comprising a Pt film oriented to (100) and a SrRuO3 film formed on the Pt film and oriented to (001);
• the Pb(Zr1-ATiA)O3 film is in contact with the foundation film;
• the Pb(Zr1-xTix)O3 crystal film is crystallized by coating and heating a solution containing, in an organic solvent, a metal compound wholly or partially containing ingredient metals of the Pb(Zr1-xTix)O3 crystal film and a partial polycondensation product thereof;
• a Zr/Ti ratio in the Pb(Zr1-xTix)O3 crystal film in the thickness direction thereof becomes gradually smaller or decreases in steps with increase in distance from the Pb(Zr1-BTiB)O3 seed crystal film;
• a Zr/Ti ratio in the Pb(Zr1-BTiB)O3 seed crystal film in the thickness direction thereof becomes gradually larger with increase in distance from the Pb(Zr1-ATiA)O3 film toward the Pb(Zr1-xTix)O3 crystal film;
• the Pb(Zr1-xTix)O3 crystal film comprises a Pb(Zr0.70Ti0.30)O3 film formed on the Pb(Zr1-BTiB)O3 seed crystal film, a Pb(Zr0.65Ti0.35)O3 film formed on the Pb(Zr0.70Ti0.30)O3 film, and a plurality of PZT films stacked and formed on the Pb(Zr0.65Ti0.35)O3 film;
• a Zr/Ti ratio in each of the Pb(Zr0.70Ti0.30)O3 film, the Pb(Zr0.65Ti0.35)O3 film, and the plurality of PZT films in the thickness direction thereof becomes gradually smaller with increase in distance from the Pb(Zr1-BTiB)O3 seed crystal film;
• a polarization direction of the Pb(Zr1-BTiB)O3 seed crystal film is identical to a polarization direction of the Pb(Zr1-xTix)O3 crystal film;
• the Pb(Zr1-BTiB)O3 seed crystal film and the Pb(Zr1-xTix)O3 crystal film are oriented to (001);
• and
• the A, the B and the x satisfy formulae 1 to 3, respectively,
• 0≤A≤0.1 formula 1
• 0.1<B<1 formula 2
• 0.1<x<1 formula 3.