Radiation damage and nanolithography

The main limitation on nanoanalysis using STEM is damage to the specimen. A striking indication of this is to estimate the dose received per picture element per second, which is given by 

In practice, a number of obvious experimental tricks are available to keep irradiation effects under control, such as focusing on one area, and moving to a contiguous area to acquire a spectrum using very short acquisition times from fresh areas to acquire noisy spectra, and then superimposing them to reconstitute an acceptable spectrum - whose spatial resolution is now governed by how close together in space the individual acquisitions can be made [3.34]. 

Of course, in some circumstances, particularly in inorganic thin films, the damage appears in the form of holes which can be used to create nanostructures. These are ROMs which are robust, carry a very high information density, and can be organised to have a short readout time. In the long run, such 

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