Electron nanodiffraction using sharply focused parallel probes

The authors describe an electron-optical configuration for producing a nanometer-scale sharply focused parallel electron probe in the transmission electron microscope. The configuration utilizes one of the round lenses in an objective prefield aberration corrector and generates a sharply focused parallel probe of 10 nm in diameter, with better than 0.2 nm edge acuity. Such a probe makes it possible to obtain electron diffraction patterns from nanometer-scale volumes of the specimen with unprecedented precision. A method for measuring the transverse coherence of the probe is also described. © 2007 American Institute of Physics