Optical Review

, Volume 3, Issue 2, pp 65–70

Consistency of the Surface Roughness Determined from Soft-X-Ray Reflectance and Surface Profiles Measured Using a Scanning Tunnelling Microscope: Coherence Length of the Soft X-Rays

  • Mihiro Yanagihara
  • Takuya Sasaki
  • Minaji Furudate
  • Masaki Yamamoto


There exists serious inconsistency between the rms surface roughness determined from the Debye-Waller factor for the soft-x-ray reflectance analysis and that measured with an optical surface profiler. We have measured the surface profile of evaporated films using a scanning tunnelling microscope, and reproduce the profile with the Fourier components whose spatial wavelength is shorter than the coherence length of the incident soft x-rays in the reflectance measurement. The rms surface roughness derived from the high-pass filtered profile agrees well with that determined using the reflectance measurement. This result explains straightforwardly the photon-energy dependence of the surface roughness estimated by the soft-x-ray reflectance method.

Key words

surface roughness reflectance soft x-ray coherence length STM 


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Copyright information

© The Optical Society of Japan 1996

Authors and Affiliations

  • Mihiro Yanagihara
    • 1
  • Takuya Sasaki
    • 1
    • 2
  • Minaji Furudate
    • 1
  • Masaki Yamamoto
    • 1
  1. 1.Research Institute for Scientific MeasurementsTohoku UniversitySendaiJapan
  2. 2.Toshiba Corp., NasuTochigiJapan

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