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Epitaxial lanthanide oxide thin films on Si for high-k gate dielectric application: Growth optimization and defect passivation

Published online by Cambridge University Press:  08 February 2017

Ayan Roy Chaudhuri ,
Andrea Fissel  and
Hans Jörg Osten
Ayan Roy Chaudhuri*
Affiliation:
Materials Science Centre, Indian Institute of Technology, Kharagpur 721302, India
Andrea Fissel
Affiliation:
Institute of Electronic Materials and Devices, Leibniz University Hannover, D-30167 Hannover, Germany
Hans Jörg Osten
Affiliation:
Institute of Electronic Materials and Devices, Leibniz University Hannover, D-30167 Hannover, Germany
*
a) Address all correspondence to this author. e-mail: ayan@matsc.iitkgp.ernet.in
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Abstract

Epitaxial layers of insulating binary lanthanide oxides have been considered as potential alternative to conventional SiO2 for gate dielectric application in future Si-based MOSFET devices, which was investigated in more detail for epitaxial Gd2O3 and Nd2O3 as model systems. Additionally, the ability to integrate epitaxial dielectric barrier layers into Si structures can usher also in a variety of novel applications involving oxide/silicon/oxide heterostructures in diverse nanoelectronic and quantum-effect devices. Although epitaxial layers of such ionic oxides with excellent structural quality can be grown using molecular beam epitaxy, they often exhibit poor electrical properties such as high leakage current density, flat band instability, poor reliability etc. owing to the presence of electrically active charge defects, generated either during the oxide layer growth or typical subsequent CMOS process steps. Based on the origin and individual character of these defects, we review various aspects of defect prevention and passivation which lead to a significant improvement in the dielectric properties of the heterostructures.

Keywords

dielectricdefectsmolecular beam epitaxy (MBE)

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Type
Invited Feature Paper
Information
Journal of Materials Research , Volume 32 , Issue 4 , 28 February 2017 , pp. 699 - 716
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Copyright © Materials Research Society 2017 

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Footnotes

Contributing Editor: Don W. Shaw
This paper has been selected as an Invited Feature Paper.

References

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