Ring structures on natural molybdenum disulfide investigated by scanning tunneling and scanning force microscopy

1991 ◽  
Vol 9 (2) ◽  
pp. 1072 ◽  
Author(s):  
Wolfgang M. Heckl
Keyword(s):  
Molybdenum Disulfide ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Force Microscopy ◽  
Ring Structures ◽  
Scanning Force

Scanned tip measurement of deep vertical facets on a flat surface: Measuring roughness on gaas laser waveguide mirrors

1993 ◽  
Vol 51 ◽  
pp. 532-533
Author(s):  
Chang Shen ◽  
Phil Fraundorf ◽  
Robert W. Harrick
Keyword(s):  
Integrated Circuits ◽  
Flat Surface ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Optoelectronic Integrated Circuits ◽  
Laser Waveguide ◽  
Scanning Force ◽  
Gaas Laser

Monolithic integration of optoelectronic integrated circuits (OEIC) requires high quantity etched laser facets which prevent the developing of more-highly-integrated OEIC's. The causes of facet roughness are not well understood, and improvement of facet quality is hampered by the difficulty in measuring the surface roughness. There are several approaches to examining facet roughness qualitatively, such as scanning force microscopy (SFM), scanning tunneling microscopy (STM) and scanning electron microscopy (SEM). The challenge here is to allow more straightforward monitoring of deep vertical etched facets, without the need to cleave out test samples. In this presentation, we show air based STM and SFM images of vertical dry-etched laser facets, and discuss the image acquisition and roughness measurement processes. Our technique does not require precision cleaving. We use a traditional tip instead of the T shape tip used elsewhere to preventing “shower curtain” profiling of the sidewall. We tilt the sample about 30 to 50 degrees to avoid the curtain effect.

Log-log scale roughness spectroscopy of surfaces

1993 ◽  
Vol 51 ◽  
pp. 224-225
Author(s):  
P. Fraundorf ◽  
B. Armbruster
Keyword(s):  
Power Spectrum ◽  
Autocorrelation Function ◽  
Power Spectra ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Force Microscopy ◽  
Scanning Force ◽  
Lateral Structure ◽  
Scale Roughness

Optical interferometry, confocal light microscopy, stereopair scanning electron microscopy, scanning tunneling microscopy, and scanning force microscopy, can produce topographic images of surfaces on size scales reaching from centimeters to Angstroms. Second moment (height variance) statistics of surface topography can be very helpful in quantifying “visually suggested” differences from one surface to the next. The two most common methods for displaying this information are the Fourier power spectrum and its direct space transform, the autocorrelation function or interferogram. Unfortunately, for a surface exhibiting lateral structure over several orders of magnitude in size, both the power spectrum and the autocorrelation function will find most of the information they contain pressed into the plot’s origin. This suggests that we plot power in units of LOG(frequency)≡-LOG(period), but rather than add this logarithmic constraint as another element of abstraction to the analysis of power spectra, we further recommend a shift in paradigm.

scholarly journals Attaboy! Attoboys, or the new Zeptoscopists

1993 ◽  
Vol 1 (8) ◽  
pp. 2-3 ◽  
Author(s):  
Jean-Paul Revel
Keyword(s):  
Optical Microscopy ◽  
Near Field ◽  
Scanning Force Microscopy ◽  
Scanning Tunneling ◽  
Far Field ◽  
Force Microscopy ◽  
Near Field Optics ◽  
Scanning Force ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning

As the year ends there is a bumper crop of announcements of advances that I find absolutely amazing. First of course is the continued clever use of light as a veritable tool in manipulating everything from atoms (entrapping them in “atomic molasses”) to having tugs of war with biological motors (using “light tweezers”). But these developments will be for discussion another time. What I want to talk about in this installment are advances in Near Field Scanning Optical Microscopy (NSOM), which has now been used by Chichester and Betzig to visualize single molecules.In classical (far field) optics, resolution is limited by diffraction to about 1/2 the wavelength of the radiation used for imaging. Near field optics overcome this limitation by use of scanning techniques similar to those employed in Scanning Tunneling or Scanning Force Microscopy.

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