DISPERSION COMPENSATION HIGH-RESOLUTION ELECTRON ENERGY-LOSS SPECTROMETER FOR TIME-RESOLVED SURFACE STUDIES

A new high-resolution electron energy-loss spectrometer based on the dispersion compensation (DC) concept has been designed, built, and tested. The parallel processing inherent in DC has allowed us to attain signal levels two orders of magnitude in excess of conventional designs while operating at comparable resolution. This is consistent with expectations based on simple model calculations. The resolving power of the spectrometer is not as good as theoretically predicted probably due to uncontrolled beam angle effects. Initial tests on a variety of systems are presented. We analyze the strengths and weaknesses of the design and suggest future improvements.