Resolution measurement for scanning electron microscopes

Conference · Wed Jun 01 04:00:00 EDT 1994

OSTI ID:10155175

Bentley, J; Kenik, E A ^[1]; Evans, N D ^[2]

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1. Oak Ridge National Lab., TN (United States)
2. Oak Ridge Inst. for Science and Education, TN (United States)

The resolution performance of a scanning electron microscope (SEM) is a primary specification of the instrument. For a high-resolution SEM (HRSEM) equipped with a field emission gun (FEG), image resolutions of less than 2 nm are commonly claimed. Generally, both manufacturers and customers identify image resolution as the single most important performance criterion. It is traditionally determined with specimens such as gold islands on bulk carbon supports, where the minimum apparent separation of two islands is claimed as the resolution. This procedure is highly subjective since the spacings are not known independently. Dodson and Joy (1990) have pointed out the paradox implicit in this approach - that ``the resolution of a given instrument can be verified only after a better instrument is available to characterize the structure spacing.`` By analogy to the now standard approach for high-resolution transmission electron microscopes (TEMs), Dodson and Joy (1990) investigated the use of Fourier Transforms (FT) of high-resolution SEM images for measuring resolution. Problems encountered by Dodson and Joy included obtaining a specimen with structural detail over the required range of spatial frequencies, and practical aspects of performing the FT processing. While we hope and expect that such FT techniques will be developed in the future, we have explored a different route to a less subjective resolution test that was also prompted by TEM experience, and which directly addresses the paradox posed by Dodson and Joy.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 10155175
• Report Number(s): CONF-940766--5; ON: DE94012747
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102
440800
47 OTHER INSTRUMENTATION
665000
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ELECTRON MICROSCOPES
GOLD
MISCELLANEOUS INSTRUMENTATION
OPERATION
PHYSICS OF CONDENSED MATTER
SCANNING ELECTRON MICROSCOPY
SPATIAL RESOLUTION
STRUCTURE AND PHASE STUDIES