Low Loss Tunable Thick Films Based on (Ba,Sr)TiO₃ and Ba₄Ti₁₃O₃₀ Materials

Abstract

Modification on microwave dielectric properties of (Ba_0.6Sr_0.4)TiO₃ (BST) materials due to the incorporation of Ba₄Ti₁₃O₃₀ (B4T13) materials was investigated. The dielectric constant of the BST materials was lowered from K_BST = 600 to K_COMP = 100, whereas the quality factor of the materials was increased markedly from (Q ×} f)_BST = 80 to (Q ×} f)_COMP = 2,000, due to the addition of B4T13 materials. Evanescent microwave probe (EMP) measurements indicate that the thick films prepared from the mixture contain two phases. The low-K and high-Q particulates, which are presumably B4T13 phase, are distributed uniformly among the high-K and low-Q matrix, resulting in a tunable materials with improved microwave dielectric properties.

ACKNOWLEDGEMENT

The authors would like to thank the financial support from the National Science Council of R.O.C through the project NSC 92-2216-E.32-006.