Characterization of the Pyroelectric Effect in Zr/Si Co-Doped HfO ₂ Thin Films

Recently, co-doping has been proposed as a method to stabilize the orthorhombic phase in HfO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> and enhance the pyroelectric response. To advance this field, the present study systematically investigates a variety of 10 nm thick Zr/Si co-doped HfO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> thin films (HZSO) with varied compositions and annealing temperatures. Transmission electron microscopy, x-ray diffraction, and x-ray photoelectronic spectroscopy are employed to elucidate the film structure and composition of the doped HfO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>, while electrical analysis asses the ferroelectric and pyroelectric properties. The highest pyroelectric coefficient was obtained in <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{HZSO}{ }_{0.88}$</tex> annealed at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$650^{\circ} \mathrm{C}\left(103 \mu \mathrm{C} / \mathrm{m}^{2} \cdot \mathrm{K}\right)$</tex>. Co-doped samples also exhibited slightly lower aging than single doped samples.