Dielectric Properties of Ba0.6Sr0.4TiO3-La(B0.5Ti0.5)O3 (B=Mg, Zn) Ceramics

Ba
_0.6
Sr
_0.4
TiO
₃
-La(B
_0.5
Ti
_0.5
)O
₃
(B = Mg, Zn) ceramics were prepared by a solid-state reaction method, and their microwave dielectric characteristics and tunability were investigated. The ferroelectric-dielectric solid solutions with cubic perovskite structures were obtained for compositions of 10 to 60 mol% La(Mg
_0.5
Ti
_0.5
)O
₃
and 10 to 50 mol% La(Zn
_0.5
Ti
_0.5
)O
₃
. With the increase of linear oxide dielectric content, the dielectric constant and tunability were decreased and Qf was increased. Ba
_0.6
Sr
_0.4
TiO
₃
-La(Mg
_0.5
Ti
_0.5
)O
₃
has better dielectric properties than Ba
_0.6
Sr
_0.4
TiO
₃
-La(Zn
_0.5
Ti
_0.5
)O
₃
. 0.9Ba
_0.6
Sr
_0.4
TiO
₃
-0.1La(Mg
_0.5
Ti
_0.5
)O
₃
has a dielectric constant epsiv = 338.2, Qf = 979 GHz and a tunability of was 3.7% at 100 kHz under 1.67 kV/mm. The Qf value of 0.5Ba
_0.6
Sr
_0.4
TiO
₃
- 0.5La(Mg
_0.5
Ti
_0.5
)O
₃
reached 9367 GHz, but the tunable properties were lost.