Multilayer BST-COC Composite with Enhanced High Frequency Dielectric Properties

The 0–3 composites with a mixture of randomly dispersed and separated ceramic particles and thermoplastic polymers provide flexible method to fabricate RF devices with adjusted mechanical and electrical properties. However, high ceramic loading levels are required to achieve high relative permittivity which, on the other hand, dramatically degrades the mechanical properties of the composite. In this work vertical and horizontal 2–2 type multilayer structures were fabricated by hot lamination of injection moulded 0–3 BST-COC composite materials with different loading levels of paraelectric ceramic (Ba 0.55 Sr 0.45 Ti 1.01 O 3 ). Each layer and the structures with gradient in permittivity and loss were characterized up to 1 GHz by impedance analyzer. The relative permittivity for the vertical and horizontal gradient structure with identical layer order and average ceramic loading of ∼ 16 vol.% was 6.54 and 10.60 at 1 GHz, respectively. The results showed that especially the horizontal structure is able to provide higher relative permittivity values than a vertical one with similar ceramic loading levels and with competitive dielectric losses. Since the introduced structure is composed of combination of ductile and brittle layers, it also offers a way to fabricate devices with improved mechanical properties.