Dielectric Properties of Rutile Structure (Zn1/3B2/3)x(TiySn1-y)1-xO2 (B=Nb5+, Ta5+) at Microwave Frequencies

The microwave dielectric properties of rutile (Zn 1/3 B 2/3 ) x (Ti y Sn 1-y ) 1-x O 2 (B = Nb 5+ , Ta 5+ , 0.05 ≤ x ≤ 0.35, y = 0.2, 0.8) were investigated with structural characteristics. A single phase with tetragonal rutile (P4 2 /mnm, no. 136, Z = 2) structure was obtained through the entire range of compositions. With an increase of (Zn 1/3 B 2/3 )O 2 content, the dielectric constant (K) of sintered specimens with (Ti 0.2 Sn 0.8 ) O 2 increased, whereas that of the specimens with (Ti 0.8 Sn 0.2 ) O 2 decreased. The temperature coefficient of resonant frequency (TCF) of sintered specimens was dependent upon oxygen octahedral distortion and/or cations bond valence of the rutile structure. The quality factor (Qf) was dependent upon (Zn 1/3 B 2/3 )O 2 content, and the specimens with (Ti 0.2 Sn 0.8 )O 2 showed larger Qf values than those with (Ti 0.8 Sn 0.2 )O 2 for the same content of (Zn 1/3 B 2/3 )O 2 .