Abstract: Al-doped ZrO₂ films with different microstructures were deposited on Si (100) substrates by using reactive RF magnetron sputtering process with metallic Zr and Al as targets in an argon-oxygen atmosphere. The films were characterized with high-resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), and atomic force microscope (AFM) to investigate variety of the thermal stability, the interfacial stability and the surface roughness of the films with different annealing temperatures. The influence of the microstructures of Al-doped ZrO₂ thin films on their electrical I-V characteristics was also discussed. The results show that the atomic content of Al in films has a significant influence on the microstructures, upon increasing the atomic content ratio of Al/Zr, the structure transition of the films is a-ZrO₂ (pure)→t-(Zr,Al)O₂ and c-(Zr,Al)O₂ (Al/Zr=1/4)→a-(Zr,Al)O₂(Al/Zr=4/5). Al-doped ZrO₂ thin films with Al/Zr atomic ratio of 4/5 has the increase in the crystallization temperature compared to a pure ZrO₂ film, so the thermal stability of the films is improved.

Key words: thin film physics, Al-doped ZrO₂ thin film, magnetron sputtering, thermal stability