Characterization of Dielectric and Piezoelectric Properties of Ferroelectric AlScN Thin Films

Abstract

The present work explores the dielectric and piezoelectric properties of ferroelectric scandium-doped aluminum nitride (AlScN) thin films. Films in a range from 20 to 500 nm are fabricated with scandium (Sc) percentages of 28%, 31%, and 36%. The rocking curves, piezoelectric coefficient d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">33</sub> , butterfly curves, capacitance and loss tangent versus voltage are characterized for different thicknesses and Sc percentage combinations. Additionally, the capacitance variation for different scandium concentrations is modeled to showcase the possibility of using AlScN thin films as varactors in a impedance matching network capable of canceling out inductance variations of up to 10%. Thus, the present work furthers the characterization efforts for AlScN ferroelectric films and steps towards transitioning them towards multi-functional platforms in for RF networks.