Abstract
The possibilities of obtaining information about interband scattering processes from electron energy-loss spectra, taken in a VG601UX scanning transmission microscope, are investigated. With the help of precise simulations of the zero-loss peak it is feasible to process, extract and analyse data in the electron volt regime. The accuracy of the results is restricted predominantly by instrumental limitations. It is possible to extract band gaps of > 2eV (e,g. for GaN) correctly. In the case of band gaps between 1 and 2 eV (i.e. in GaAs), the uncertainty is larger, since the tail of the zero-loss peak interferes with the interband losses, and further refinements in the data analysis as well as the measurement techniques are discussed. 'Band-gap mapping' in the VG601UX can be carried out with a spatial resolution of a few nanometres.
Original language | English |
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Pages (from-to) | 173-180 |
Number of pages | 8 |
Journal | Ultramicroscopy |
Volume | 68 |
Issue number | 3 |
DOIs | |
Publication status | Published - Jul 1997 |
Externally published | Yes |