Atomic Layer Deposition and Characterization of Dysprosium-Doped Zirconium Oxide Thin Films†

Abstract

Dy₂O₃ doped ZrO₂ films are grown on silicon substrates using atomic layer deposition at 300 °C. Dy(thd)₃ (thd = 2,2,6,6-tetramethyl-3,5-heptanedionato) and ZrCl₄ are used as metal precursors and H₂O as the oxygen precursor. Despite the low growth rate of Dy₂O₃ in a beta-diketonate/water process, the process allows deposition of thin films with the dysprosium content of few mass %. The films crystallize in the form of tetragonal zirconia already in as-deposited state and grow conformally onto 3D substrates with an aspect ratio of 1:20. The capacitors formed on the basis of the films in as-deposited and annealed states demonstrate current–voltage and capacitance behavior characteristic of those with high-permittivity dielectrics. The maximum concentration of electronic defects at oxide/electrode interfaces reaches 1.8 × 10¹¹ cm⁻² eV⁻¹.