Nanostructured Er2O3 thin films grown by metalorganic chemical vapour deposition

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Ke Xu - , Ruhr University Bochum (Author)
  • Van Son Dang - , Ruhr University Bochum (Author)
  • Andreas Ney - , Johannes Kepler University Linz (Author)
  • Teresa De Los Arcos - , Ruhr University Bochum (Author)
  • Anjana Devi - , Ruhr University Bochum (Author)

Abstract

Metalorganic chemical vapor deposition (MOCVD) of nanostructured Er 2O3 thin films was performed using the Er-tris-guanidinate precursor [Er(DPDMG)3] (DPDMG = diisopropyl-2- dimethylamidoguanidinato) as the Er source and oxygen. Film deposition was carried out on Si(100) and quartz glass substrates and the process parameters namely temperature, pressure and oxygen flow rate were varied. The resulting thin films were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) for investigating the crystallinity and morphology, respectively. The chemical composition of the film was investigated by X-ray photoelectron spectroscopy (XPS) measurements. Transmittance and absorption spectra of the 600 °C film grown on glass substrates were performed by UV-vis measurements revealing more than 80% transmittance. The potential of Er2O3 thin films as gate dielectrics was verified by carrying out capacitance-voltage (C-V ) and current-voltage (I-V ) measurements. Dielectric constants estimated from the accumulation capacitance were found to be in the range of 10-12 in AC frequencies of 1 MHz down to 10 kHz and the leakage current of the order of 2×10-8 A/cm2 at the applied field of 1 MV cm-1 was measured for films deposited under optimised process conditions. The low leakage current and high dielectric constant implies good quality of the Er2O3 layers relevant for high-k applications. These layers were found to be paramagnetic with a slightly reduced magnetic moment of the Er3+ ions.

Details

Original languageEnglish
Pages (from-to)5095-5102
Number of pages8
JournalJournal of nanoscience and nanotechnology
Volume14
Issue number7
Publication statusPublished - Jul 2014
Peer-reviewedYes
Externally publishedYes

Keywords

Keywords

  • Dielectric Constant, MOCVD, Optical Properties, Paramagnetic