Abstract
Abstract
A method to improve the energy resolution of the recently proposed projection-type electron spectroscopy collimator analyzer (PESCATORA) is presented. PESCATORA is a simple, highly compact two-dimensional electron analyzer with a wide acceptance angle of up to ±60°. The use of a combined planar retarding field and parallel-hole collimator (PRF–PHC) as a band-pass filter is analytically and numerically studied. In PESCATORA, a parallel-hole collimator placed behind a specially designed electrostatic collimator lens is used as a band-pass filter to obtain energy-resolved angular distributions of emitted or diffracted electrons (or charged particles) from sample surfaces. The PRF–PHC system can be introduced in PESCATORA by simply adding a planar grid in front of the collimator plate. This allows the transmittance and energy resolution to be effectively controlled by only changing the retarding voltage of PRF, consequently improving PESCATORA. Moreover, an improved PESCATORA instrument with the highest possible specifications is presented.