HRTEM at half-Angstrom resolution: From OAM to TEAM

Conference · Mon Feb 17 04:00:00 EST 2003

OSTI ID:810869

O'Keefe, Michael A ^[1]

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1. LBNL Library

Transmission electron microscopy (TEM) at sub-Angstrom resolution is important for nanotechnology. Identifying atom positions requires appropriate resolution, the ability to separate distinct objects in images. With Cs corrected, the information limit of the TEM controls resolution. The OAM has demonstrated that a resolution of 0.78A is possible. The TEAM (transmission electron achromatic microscope) will be a TEM using hardware correction of Cs with a monochromator to improve its information limit beyond that of the OAM by improvement of the electron-beam energy spread. It is shown that A 300keV HRTEM TEAM does not require a Cc corrector to reach 0.5A as long as beam energy spread and objective-lens current ripple are lowered sufficiently. A lower-voltage TEAM will require stricter limits on objective-lens current ripple to reach the targeted 0.5A resolution. No improvement in HT ripple or noise is required to improve the information limit per se since the monochromator determines the energy spread in the beam. However, improved HT ripple and noise will improve the beam current statistics (number of electrons passing through the monochromator) by placing more of the electrons closer to the center of the energy-spread distribution

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science. Office of Basic Energy Sciences. Materials Science and Engineering Division (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 810869
• Report Number(s): LBNL--52191
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
47 OTHER INSTRUMENTATION
ATOMS
BEAM CURRENTS
DEEP-SUB-ANGSTROM HALF-ANGSTROM TEAM OAM
DISTRIBUTION
ELECTRON MICROSCOPY
ELECTRONS
MONOCHROMATORS
RESOLUTION
STATISTICS
TRANSMISSION ELECTRON MICROSCOPY