Journal ArticleDOI

# Kinetic-energy induced smoothening and delay of epitaxial breakdown in pulsed-laser deposition

24 Aug 2007-Physical Review B (American Physical Society)-Vol. 76, Iss: 8, pp 085431

AbstractWe have isolated the effect of kinetic energy of depositing species from the effect of flux pulsing during pulsed-laser deposition (PLD) on surface morphology evolution of Ge(001) homoepitaxy at low temperature $(100\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C})$. Using a dual molecular beam epitaxy (MBE) PLD chamber, we compare morphology evolution from three different growth methods under identical experimental conditions except for the differing nature of the depositing flux: (a) PLD with average kinetic energy $300\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ (PLD-KE); (b) PLD with suppressed kinetic energy comparable to thermal evaporation energy (PLD-TH); and (c) MBE. The thicknesses at which epitaxial breakdown occurs are ranked in the order $\mathrm{PLD}\text{\ensuremath{-}}\mathrm{KE}g\mathrm{MBE}g\mathrm{PLD}\text{\ensuremath{-}}\mathrm{TH}$; additionally, the surface is smoother in PLD-KE than in MBE. The surface roughness of the films grown by PLD-TH cannot be compared due to the early epitaxial breakdown. These results demonstrate convincingly that kinetic energy is more important than flux pulsing in the enhancement of epitaxial growth, i.e., the reduction in roughness and the delay of epitaxial breakdown.

Topics: Order (ring theory) (55%)

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##### References
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Book ChapterDOI
01 Jan 1994
Abstract: Partial table of contents: History and Fundamentals of Pulsed Laser Deposition (J. Cheung). Diagnostics and Characteristics of Laser--Produced Plasmas (D. Geohegan). Particulates Generated by Pulsed Laser Ablation (L.--C. Chen). Angular Distribution of Ablated Material (K. Saenger). Film Nucleation and Film Growth in Pulsed Laser Deposition of Ceramics (J. Horwitz & J. Sprague). Processes Characteristics and Film Properties in Pulsed Laser Plasma Deposition (S. Metev). Commercial Scale--Up of Pulsed Laser Deposition (J. Greer). Pulsed Laser Deposition: Future Trends (T. Venkatesan). Comparison of Vacuum Deposition Techniques (G. Hubler). Pulsed Laser Deposition of High--Temperature Superconducting Thin Films for Active and Passive Device Applications (R. Muenchausen & X. Wu). Pulsed Laser Deposition of Metals (J. Kools). Appendix. References. Index.

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