Miniaturized notch antenna based on lanthanum titanium perovskite oxide thin films
Abstract
This paper presents the integration of a dielec. La2Ti2O7 compd. as thin film in a discrete capacitive component operating at microwaves. The integration in a notch antenna of a MIM (metal/insulator/metal) structure based on this oxide material is numerically and exptl. studied. Oxide films are deposited by reactive magnetron r.f. sputtering of an La2Ti2O7 target. The films are composed of an unusual phase: the orthorhombic La2Ti2O7 compd., with a textured growth on Pt/Si and Pt/SrTiO3 substrates. Moderate dielec. const. values (ε ≈ 60) and low loss (tan δ < 0.005) are obtained at 1 GHz. Inserting this original MIM capacitor in the antenna structure results in a shift to a lower value of its operating frequency. This shift, from 885-317 MHz, corresponds to a significant size redn. of 64.2%. The measured values are confronted with simulation obtained by numerical software.