Size-dependent structural transition from multiple-twinned particles to epitaxial fcc nanocrystals and nanocrystal decay

Journal Article · Mon Oct 01 00:00:00 EDT 2007 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.76.144113· OSTI ID:21052712

Sato, K; Huang, W J; Bohra, F; Sivaramakrishnan, S; Tedjasaputra, A P; Zuo, J M ^[1]

---

1. Department of Materials Science and Engineering and Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

The size dependence of structural transition from multiple-twinned particles (MTP) to epitaxial face centered cubic nanocrystals was investigated for Ag nanoparticles formed on Si(001) surfaces by in situ reflection high-energy electron diffraction and ex situ transmission electron microscopy. The transition from MTP to nanocrystals was promoted by postdeposition annealing. Clear particle size dependence is found in the epitaxial formation temperatures (T{sub E}), which is about 2/3 of the calculated, size-dependent, melting temperature (T{sub M}) using the value of surface energy {gamma}{sub S}=1.2 J/m{sup 2} for larger particles (>2 nm). Once nanocrystals are formed, they decay and disappear in a narrow temperature range between 795 and 850 K. No evidence of nanocrystal melting was detected from the reflection high-energy electron diffraction observations.

• OSTI ID: 21052712
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 76, Issue 14; Other Information: DOI: 10.1103/PhysRevB.76.144113; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANNEALING
DECAY
ELECTRON DIFFRACTION
EPITAXY
FCC LATTICES
MELTING
MELTING POINTS
NANOSTRUCTURES
PARTICLE SIZE
PARTICLES
REFLECTION
SEMICONDUCTOR MATERIALS
SILICON
SILVER
SOLIDS
SURFACE ENERGY
SURFACES
TEMPERATURE RANGE 0400-1000 K
TRANSMISSION ELECTRON MICROSCOPY