Epitaxial YSZ films on Si have been made with PLD since the 90 s. Initially, YSZ films were grown on Si with the native oxide removed in advance7. Growth on silicon with native oxide was introduced short time later17, and appeared to deliver films with higher crystalline qualities6,10,18. Typically, a two step growth process is used8,13. The first couple of nm are deposited in low oxygen pressure to perform a scavenging reaction. ZrO2 and Y2O3 have lower Gibbs free energies of formation compared to SiO2. Therefore, Zr and Y will scavenge the oxygen from the silicon oxide when brought into contact with silicon oxide in low oxygen pressures17,19. The decomposition of the native oxide occurs most probably by formation of volatile SiO, corresponding to the following reaction6:1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Zr+2Si{O}_{2}\to 2SiO\uparrow +Zr{O}_{2}$$\end{document}Zr+2SiO2→2SiO↑+ZrO2