Thermal stability of hafnium zirconium oxide on transition metal dichalcogenides

Ferroelectric oxides interfaced with transition metal dichalcogenides (TMDCs) offer a promising route toward ferroelectric-based devices due to lack of dangling bonds on the TMDC surface leading high-quality and abrupt ferroelectric/TMDC interface. In this work, thermal stability interface is explored by first depositing hafnium zirconium oxide (HZO) directly geological MoS2 as-grown WSe2, followed sequential annealing in ultra-high vacuum (UHV) over range temperatures (400-800 {\deg}C), examining through X-ray photoelectron spectroscopy (XPS). We show that nucleation HZO grown atomic layer deposition (ALD) varied depending functionalization TMDC, conditions can cause tungsten oxidation WSe2. It was observed deposited non-functionalized unstable volatile upon annealing, while functionalized stable 400-800 {\deg}C range. The HZO/WSe2 until 700 {\deg}C, after which Se began evolve from addition, there evidence oxygen vacancies film being passivated at high temperatures. Lastly, diffraction (XRD) used confirm crystallization within temperature studied.