Effect of Si substrate on interfacial SiO{sub 2} scavenging in HfO{sub 2}/SiO{sub 2}/Si stacks
- Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan)
The scavenging kinetics of an ultra-thin SiO{sub 2} interface layer (SiO{sub 2}-IL) in an HfO{sub 2}/SiO{sub 2}/Si stack is discussed by focusing on the substrate effect in addition to oxygen diffusion. {sup 18}O tracing experiments demonstrate that the O-atom moves from the SiO{sub 2}-IL to the HfO{sub 2} layer during scavenging. SiO{sub 2}-IL scavenging with various substrates (Si, SiC, and sapphire) has been found to be significantly different, which suggests that the Si in the substrate is also necessary to continuously cause the scavenging. Based on these findings and thermodynamic considerations, a kinetic model where oxygen vacancy (V{sub O}) transferred from the HfO{sub 2} reacts with the SiO{sub 2}, which is in contact with the Si-substrate, is proposed for the SiO{sub 2}-IL scavenging.
- OSTI ID:
- 22310710
- Journal Information:
- Applied Physics Letters, Vol. 105, Issue 18; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Characteristics of remote plasma atomic layer-deposited HfO{sub 2} films on O{sub 2} and N{sub 2} plasma-pretreated Si substrates
Scanning Transmission Electron Microscopy Investigations of Interfacial Layers in HfO2 Gate Stacks