Abstract
The interface between Cu and HfO2 synthesized using physical vapor deposition at 300 K has been examined with in situ low-energy ion scattering (LEIS), in situ X-ray photoelectron spectroscopy (XPS) and ex situ scanning transmission electron microscopy (STEM). Cu deposited on HfO2 at 300 K readily forms three-dimensional clusters. LEIS and XPS data show that the Cu is not oxidized at the Cu-HfO2 interface. A proposed model allows simulation of the coverage of Cu as a function of Cu dosing time before and after thermal annealing. At 300 K, the model fits the data when two-dimensional islands cover no more than 90% of the HfO2 surface. After thermal annealing at 673 K for 10 min under vacuum (1 × 10-8 Torr), large Cu clusters are formed from smaller ones, but there is no evident diffusion into the HfO2. For this annealed sample, STEM shows a narrow cluster diameter distribution (10-12 nm). Strain fields at the hafnia-copper interface may help limit the cluster size distribution.
Original language | English (US) |
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Pages (from-to) | 1-9 |
Number of pages | 9 |
Journal | Surface Science |
Volume | 521 |
Issue number | 1-2 |
DOIs | |
State | Published - Dec 10 2002 |
Externally published | Yes |
Keywords
- Clusters
- Copper
- Growth
- X-ray photoelectron spectroscopy
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry