Temperature-stabilized piezoelectric ceramics for acoustic surface-wave filters

Suppression of temperature variation and improvement of surface roughness on filter materials were accomplished by using hot-pressed piezoelectric ceramics consisting of ternary complex ceramics, PbTiO
3
and PbZrO
3
, and a compound Pb(Mn
1/3
Nb
2/3
)O
3
. The electromechanical coupling factor k
s
was 0.239, temperature variation of wave velocity TV
s
, was 17 ppm/°C, and average pore size was 1.5 µm. The ceramics obtained are suitable for such practical devices as surface-wave filters.