Fig. 2. Insertion loss, return loss, S21 phase, and phase change for multilayer ferroelectric over LaAlO3 compared with conductors directly on Ba0.6Sr0.4TiO3 [3]. The figures show reduction in insertion losses (a), improved return loss (b), and large change in phase of S21 and the total phase change (c) and (d). Results represent comparison between the multilayer approach and the direct conductor on BSTO case [3].

The results show an improvement in insertion loss of up to 5 dB at 10 GHz. Significant improvements in return loss may also be observed. Fig. 3 shows that the new design significantly out performed the direct metallization on the Ferroelectric material approach. The design configurations shown in Fig. 3 produced a figure of merit of over 25 o/dB at 10 GHz in addition to a significant improvement in insertion and return losses.

The design configurations shown in Fig. 2b produced a figure of merit of over 25 o/dB at 10 GHz in addition to a significant improvement in insertion and return losses. It should also be noted that the multilayered structure shown in Fig. 1b with sub and superstrate dielectric loading generated a figure of merit of over 30 °/dB at 10GHz.

The simulated results for the case with conductors directly on the Ferroelectric film agree very well with measured results from [3]. The simulated results was based on an in house method of moment computer code for multilayer structures and provided an accurate analysis for modeling Ferroelectric materials with a tensor based permittivity. The same approach was conducted for the analysis of the multilayered Ferroelectric structure described in Fig. 2b.