Atomic Layer Deposition of Cerium Dioxide Film on TiN and Si Substrates: Structural and Chemical Properties

TL;DR

This study investigates the structural and chemical properties of CeO2 thin films deposited by atomic layer deposition on Si and TiN substrates, revealing differences in crystallographic orientation and oxygen vacancy levels.

Contribution

It provides new insights into the orientation and chemical composition of ALD-deposited CeO2 films on different substrates, aiding future application development.

Findings

CeO2 films are cubic polycrystalline on both substrates.

Different preferred orientations: <200> on Si, <111> on TiN.

Presence of oxygen vacancies indicated by Ce3+ concentrations.

Abstract

Cerium dioxide (CeO2) thin films were deposited by atomic layer deposition (ALD) on both Si and TiN substrates. The ALD growth produces CeO2 cubic polycrystalline films on both substrates. However, the films show a preferential orientation along <200> crystallographic direction for CeO2/Si or <111> for CeO2/TiN. In correspondence, we measure a relative concentration of Ce3+ equals to 22.0% in CeO2/Si and around 18% in CeO2/TiN, by X-ray photoelectron spectroscopy. Such values indicate the presence of oxygen vacancies in the films. Our results extend the knowledge on the structural and chemical properties of ALD-deposited CeO2 either on Si or TiN substrates, underlying films differences and similarities, thus contributing to boost the use of CeO2 through ALD deposition as foreseen in a wide number of applications.