Degradation kinetics of ultrathin HfO2 layers on Si(1 0 0) during vacuum annealing monitored with in situ XPS/LEIS and ex situ AFM

doi:10.1016/j.microrel.2007.01.071

Microelectronics Reliability

Volume 47, Issues 4–5, April–May 2007, Pages 657-659

https://doi.org/10.1016/j.microrel.2007.01.071 Get rights and content

Abstract

The evolution of HfO₂(3–5 nm)/SiO₂(0.5 nm)/Si(1 0 0) stacks during vacuum annealing was monitored in situ with the combination of X-ray photoelectron spectroscopy and low energy ion scattering techniques and supplemented with atomic force microscopy analysis to investigate the mechanism that triggers HfO₂ degradation with Hf silicide formation. The reduction of SiO₂ interfacial layer and the formation of local paths for SiO escape into vacuum are believed to be critical at vacuum annealing above T > 850 °C for the reaction between HfO₂ and Si to start and eventually lead to the degradation of the former.

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Citation Excerpt :
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Degradation kinetics of ultrathin HfO2 layers on Si(1 0 0) during vacuum annealing monitored with in situ XPS/LEIS and ex situ AFM

Abstract

Microelectron Eng

Microelectron Eng

Surf Sci

J Appl Phys

J Appl Phys

J Appl Phys

Appl Phys Lett

Appl Phys Lett

Degradation kinetics of ultrathin HfO₂ layers on Si(1 0 0) during vacuum annealing monitored with in situ XPS/LEIS and ex situ AFM