The authors from RUB gratefully acknowledge the German Research Foundation (DFG) for funding this project (DFG-DE-790-9-1) as well as Prof. R. A. Fischer for his continuous support. KX expresses his appreciation to the RUB-Research School for granting a PhD research fellowship.
Atomic Layer Deposition of HfO2 Thin Films Employing a Heteroleptic Hafnium Precursor†
Article first published online: 5 MAR 2012
Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chemical Vapor Deposition
Volume 18, Issue 1-3, pages 27–35, March 2012
How to Cite
Xu, K., Milanov, A. P., Parala, H., Wenger, C., Baristiran-Kaynak, C., Lakribssi, K., Toader, T., Bock, C., Rogalla, D., Becker, H.-W., Kunze, U. and Devi, A. (2012), Atomic Layer Deposition of HfO2 Thin Films Employing a Heteroleptic Hafnium Precursor. Chem. Vap. Deposition, 18: 27–35. doi: 10.1002/cvde.201106934
- Issue published online: 16 MAR 2012
- Article first published online: 5 MAR 2012
- Manuscript Revised: 8 JUL 2011
- Manuscript Received: 14 APR 2011
- German Research Foundation (DFG). Grant Number: DFG-DE-790-9-1
- Thin Films;
The application of a heteroleptic hafnium amide-guanidinate precursor for the deposition of HfO2 thin films via a water-assisted atomic layer deposition (ALD) process is demonstrated for the first time. HfO2 films are grown in the temperature range 100–300 °C using the compound [Hf(NMe2)2(NMe2-Guan)2] (1). This compound shows self-limiting ALD-type growth characteristics with growth rates of the order of 1.0–1.2 Å per cycle in the temperature range 100–225 °C. The saturation behavior and a linear dependence on film thickness as a function of number of cycles are verified at various temperatures within the ALD window. The as-deposited HfO2 films are characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS), and electrical measurements. For a direct comparison of the precursor performance with that of the parent alkyl amide [Hf(NMe2)4] (2), ALD experiments are also performed employing compound 2 under similar process conditions, and in this case no typical ALD characteristics are observed.