Enhancement of superior dielectric performance in ZnTiNb₂O₈ systems by multi‐layer architecture

Abstract

Zn0.995Cu0.005TiNb2O8@TiO2 mixed ceramics and Zn0.995Cu0.005TiNb2O8‐TiO2‐Zn0.995Cu0.005TiNb2O8 layered ceramics with different TiO2 contents were designed and manufactured to adjust the microwave dielectric performances of Zn0.995Cu0.005TiNb2O8/TiO2 composite ceramics. The effects of random distribution and laminated co‐firing processes on the microwave dielectric properties of the ZnTiNb2O8 systems were fully investigated and compared. During the random distribution process, the compound transforms from the original ZnTiNb2O8 phase to the Zn0.17Nb0.33Ti0.5O2 phase with the increase of TiO2 content. Its value can be adjusted to near zero, but its Q× f value decreases severely. For the laminated co‐firing process, the distinctive tri‐layer architecture allows the reaction between Zn0.995Cu0.005TiNb2O8 and TiO2 to be limited to a narrow region of about 20 µm width and can play a role similar to that of “glue” to connect the layers well. The process significantly minimizes the probability of Q× f values deteriorating. Compared with the random distribution Zn0.995Cu0.005TiNb2O8@TiO2, the Q× f value of the tri‐layer architecture ceramics is improved by about 85% with no significant decrease in dielectric permittivity while ensuring high‐temperature stability. When stacked with 0.04 wt% TiO2, the Zn0.995Cu0.005TiNb2O8‐TiO2‐Zn0.995Cu0.005TiNb2O8 tri‐layer architecture ceramic exhibits superior dielectric properties: = 39.96, Q× f = 51,987 GHz, and = ‐1.31 ppm/°C.