skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers

 [1];  [2];  [2];  [1]
  1. Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA
  2. Fraunhofer Institute for Material and Beam Technology, Winterbergstraße 28, 01277 Dresden, Germany
Publication Date:
Sponsoring Org.:
OSTI Identifier:
Grant/Contract Number:
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 122; Journal Issue: 11; Related Information: CHORUS Timestamp: 2018-02-14 20:20:41; Journal ID: ISSN 0021-8979
American Institute of Physics
Country of Publication:
United States

Citation Formats

Voronov, D. L., Gawlitza, P., Braun, S., and Padmore, H. A. Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers. United States: N. p., 2017. Web. doi:10.1063/1.4991377.
Voronov, D. L., Gawlitza, P., Braun, S., & Padmore, H. A. Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers. United States. doi:10.1063/1.4991377.
Voronov, D. L., Gawlitza, P., Braun, S., and Padmore, H. A. 2017. "Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers". United States. doi:10.1063/1.4991377.
title = {Spontaneous formation of highly periodic nano-ripples in inclined deposition of Mo/Si multilayers},
author = {Voronov, D. L. and Gawlitza, P. and Braun, S. and Padmore, H. A.},
abstractNote = {},
doi = {10.1063/1.4991377},
journal = {Journal of Applied Physics},
number = 11,
volume = 122,
place = {United States},
year = 2017,
month = 9

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on September 19, 2018
Publisher's Accepted Manuscript

Save / Share:
  • We use cross-sectional transmission electron microscopy to study the damage induced below the surface of indium phosphide (InP) samples by single and multiple femtosecond laser pulses with a photon energy lower than the InP band gap. Single-pulse irradiation creates a {approx}100 nm deep crater with a resolidified surface layer consisting of quasiamorphous indium phosphide. The resolidified layer has a thickness of {approx}60 nm at the center and extends laterally beyond the edge of the crater rim. Exposure to multiple femtosecond pulses of 2050 nm center wavelength results in the formation of laser-induced periodic surface structures (LIPSS) with two different periods,more » one ({approx}1730 nm) less than but close to the laser wavelength and one ({approx}470 nm) four times smaller. Segregation beneath both types of ripples leads to the formation of In-rich particles embedded in the resolidified surface layer. Extended defects are detected only below the center of the multiple-pulse crater and their distribution appears to be correlated with the LIPSS modulation. Finally, LIPSS formation is discussed in terms of the observed subsurface microstructures.« less
  • Several new amorphous alloys were obtained in an immiscible Y-Nb system by room temperature 190 keV xenon ion mixing of Y-Nb multilayered films, which were designed to include a sufficient fraction of interfacial atoms and thus possessed a high free energy comparable to that of the amorphous state. In addition, two metastable f.c.c. phases were formed in Y-rich and Nb-rich multilayered films, respectively. The growth kinetics of the f.c.c. phases and their effect on the composition range of amorphization are also discussed. To understand the observed unusual alloying behaviors, a Gibbs free-energy diagram was constructed based on Miedema`s model. Themore » diagram included the free-energy curves of all the involved phases as well as that of the Y-Nb multilayered films including the extra interfacial free energy and thus gave a qualitative and reasonable interpretation to the formation of metastable alloys upon ion mixing. Furthermore, some multilayered films with a sufficient fraction of interfacial atoms were subjected to steady-state thermal annealing, which also resulted in the formation of the Y-Nb amorphous phases, suggesting that alloying in this immiscible system was actually driven by the interfacial free energy.« less
  • Most detected planet-bearing binaries are in wide orbits, for which a high inclination, i{sub B} , between the binary orbital plane and the plane of the planetary disk around the primary is likely to be common. In this paper, we investigate the intermediate stages-from planetesimals to planetary embryos/cores-of planet formation in such highly inclined cases. Our focus is on the effects of gas drag on the planetesimals' orbital evolution, in particular on the evolution of the planetesimals' semimajor axis distribution and their mutual relative velocities. We first demonstrate that a non-evolving axisymmetric disk model is a good approximation for studyingmore » the effects of gas drag on a planetesimal in the highly inclined case (30 deg. < i{sub B} < 150 deg.). We then find that gas drag plays a crucial role, and the results can be generally divided into two categories, i.e., the Kozai-on regime and the Kozai-off regime, depending on the specific value of i{sub B} . For both regimes, a robust outcome over a wide range of parameters is that planetesimals migrate/jump inward and pile up, leading to a severely truncated and dense planetesimal disk around the primary. In this compact and dense disk, collision rates are high but relative velocities are low, providing conditions that are favorable for planetesimal growth and potentially allow for the subsequent formation of planets.« less
  • Quasi-periodic nano- and microstructures have been formed on silicon surface using IR ( {lambda} Almost-Equal-To 744 nm) and UV ( {lambda} Almost-Equal-To 248 nm) femtosecond laser pulses. The influence of the incident energy density and the number of pulses on the structured surface topology has been investigated. The silicon nanostructurisation thresholds have been determined for the above-mentioned wavelengths. Modulation of the surface relief at the doubled spatial frequency is revealed and explained qualitatively. The periods of the nanostructures formed on the silicon surface under IR and UV femtosecond laser pulses are comparatively analysed and discussed.