Secondary electron line scans over high resolution resist images: Theoretical and experimental investigation of induced local electrical field effects

Author(s):  
Luca Grella
Author(s):  
T. Miyokawa ◽  
H. Kazumori ◽  
S. Nakagawa ◽  
C. Nielsen

We have developed a strongly excited objective lens with a built-in secondary electron detector to provide ultra-high resolution images with high quality at low to medium accelerating voltages. The JSM-6320F is a scanning electron microscope (FE-SEM) equipped with this lens and an incident beam divergence angle control lens (ACL).The objective lens is so strongly excited as to have peak axial Magnetic flux density near the specimen surface (Fig. 1). Since the speciien is located below the objective lens, a large speciien can be accomodated. The working distance (WD) with respect to the accelerating voltage is limited due to the magnetic saturation of the lens (Fig.2). The aberrations of this lens are much smaller than those of a conventional one. The spherical aberration coefficient (Cs) is approximately 1/20 and the chromatic aberration coefficient (Cc) is 1/10. for accelerating voltages below 5kV. At the medium range of accelerating voltages (5∼15kV). Cs is 1/10 and Cc is 1/7. Typical values are Cs-1.lmm. Cc=l. 5mm at WD=2mm. and Cs=3.lmm. Cc=2.9 mm at WD=5mm. This makes the lens ideal for taking ultra-high resolution images at low to medium accelerating voltages.


Author(s):  
William Krakow ◽  
Alec N. Broers

Low-loss scanning electron microscopy can be used to investigate the surface topography of solid specimens and provides enhanced image contrast over secondary electron images. A high resolution-condenser objective lens has allowed the low-loss technique to resolve separations of Au nucleii of 50Å and smaller dimensions of 25Å in samples coated with a fine grained carbon-Au-palladium layer. An estimate of the surface topography of fine grained vapor deposited materials (20 - 100Å) and the surface topography of underlying single crystal Si in the 1000 - 2000Å range has also been investigated. Surface imaging has also been performed on single crystals using diffracted electrons scattered through 10−2 rad in a conventional TEM. However, severe tilting of the specimen is required which degrades the resolution 15 to 100 fold due to image forshortening.


Planta ◽  
1980 ◽  
Vol 147 (5) ◽  
pp. 396-404 ◽  
Author(s):  
G. Pilwat ◽  
R. Hampp ◽  
U. Zimmermann

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