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

Title: Ion Beam Induced Surface Modulations from Nano to Pico: Optimizing Deposition During Erosion and Erosion During Deposition.

Conference ·

Ion beams of sufficient energy to erode a surface can lead to surface modulations that depend on the ion beam, the material surface it impinges, and extrinsic parameters such as temperature and geometric boundary conditions. Focused Ion Beam technology both enables site-specific placement of these modulations and expedites research through fast, high dose and small efficient use of material. The DualBeam (FIB/SEM) enables in situ metrology, with movies observing ripple formation, wave motion, and the influence of line defects. Nanostructures (ripples of >400nm wavelength to dots spaced <40nm) naturally grow from atomically flat surfaces during erosion, however, a steady state size may or may not be achieved as a consequence of numerous controlled parameters: temperature, angle, energy, crystallography. Geometric factors, which can be easily invoked using a FIB, enable a controlled component of deposition (and/or redeposition) to occur during erosion, and conversely allow a component of etching to be incurred during (ion-beam assisted) deposition. High angles of ion beam inclination commonly lead to 'rougher' surfaces, however, the extreme case of 90.0{sup o} etching enables deposition of organized structures 1000 times smaller than the aforementioned, video-recorded nanostructures. Orientation and position of these picostructures (naturally quantized by their atomic spacings) may be controlled by the same parameters as for nanostructures (e.g. ion inclination and imposed boundary conditions, which are flexibly regulated by FIB). Judicious control of angles during FIB-CVD growth stimulates erosion with directionality that produces surface modulations akin to those observed for sputtering. Just as a diamond surface roughens from 1-D ripples to 2-D steps with increasing angle of ion sputtering, so do ripples and steps appear on carbon-grown surfaces with increase in angle of FIB-CVD. Ion beam processing has been a stalwart of the microelectronics industry, is now a vital tool for research of self-organizing nanostructures, and promises to be a focus for future picotechnology.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
923992
Report Number(s):
UCRL-PROC-236448; TRN: US0801997
Resource Relation:
Journal Volume: 1059; Conference: Presented at: Materials Research Society, Boston, MA, United States, Nov 24 - Nov 30, 2006
Country of Publication:
United States
Language:
English

References (12)

Theory of ripple topography induced by ion bombardment journal July 1988
The effects of surface ripples on sputtering erosion rates and secondary ion emission yields journal January 1999
The Effect of Excess Carbon on the Crystallographic, Microstructural, and Mechanical Properties of CVD Silicon Carbide Fibers journal January 2006
Real-time observation of ripple structure formation on a diamond surface under focused ion-beam bombardment journal March 2001
Surface Rippling & Ion Etch Yields of Diamond Using a Focused Ion Beam: With or Without Enhanced-Chemistry, Aspect Ratio Regulates Ion Etching journal November 2006
Lateral templating of self-organized ripple morphologies during focused ion beam milling of Ge
  • Ichim, Stefan; Aziz, Michael J.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 23, Issue 3 https://doi.org/10.1116/1.1897711
journal January 2005
Spontaneous Pattern Formation from Focused and Unfocused Ion Beam Irradiation journal January 2001
Surface Modification Energized by FIB: The Influence of Etch Rates & Aspect Ratio on Ripple Wavelengths journal January 2006
Focused ion beam milling of diamond: Effects of H[sub 2]O on yield, surface morphology and microstructure
  • Adams, D. P.; Vasile, M. J.; Mayer, T. M.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 21, Issue 6 https://doi.org/10.1116/1.1619421
journal January 2003
Ion beams in silicon processing and characterization journal May 1997
A mechanism of surface micro-roughening by ion bombardment journal November 1973
Fundamentals of Focused Ion Beam Nanostructural Processing: Below, At, and Above the Surface journal May 2007