Morphological instability of a terrace edge during step-flow growth

Journal Article · Thu Mar 15 04:00:00 EST 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.5500· OSTI ID:7000894

Bales, G S; Zangwill, A ^[1]

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1. School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430 (USA)

We consider the possibility that monoatomic terrace edges undergo a morphological instability during epitaxial {ital step-flow} growth. A linear stability analysis predicts that such an instability {ital can} occur, but only when the energy barriers to adatom attachment to steps {ital differ} for adatoms that approach a step from {ital opposite} directions. The instability is diffusional in origin and manifests itself as a distinct waviness or meandering of the terrace edges as they propagate across the crystal. Our results, presented in the form of a morphological phase diagram, show that single-crystal growth on a vicinal surface can pass from stable step flow to unstable step flow to two-dimensional island nucleation and spreading as one increases the incident flux in a molecular-beam-epitaxy experiment at elevated temperature. The instability we predict should be readily distinguishable from simple thermal fluctuations.

• OSTI ID: 7000894
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 41:9; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

656002* -- Condensed Matter Physics-- General Techniques in Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRYSTALS
DIAGRAMS
EPITAXY
MOLECULAR BEAM EPITAXY
PHASE DIAGRAMS
STABILITY
TEMPERATURE DEPENDENCE