Bremsstrahlung Produced by 5 keV Electrons Incident on Al2O3 and MgO Samples at Air Pressures of 30, 50, and 100 Pa.

Bremsstrahlung spectra produced by 5 keV electrons incident on Al2O3 and MgO targets at air pressures of 30, 50, and 100 Pa have been compared with results produced using pyPENELOPE, a program designed to simulate electron microscopy. The comparisons showed that the experimental results were in good agreement with the results simulated using pyPENELOPE, except near the Duane-Hunt limit, where the bremsstrahlung amplitudes were consistently greater than PENEPMA predicted. The discrepancies may be due to charging effects, which are not simulated by PENEPMA, the Monte Carlo code on which pyPENELOPE is based. If so, the phenomena could potentially impact the accuracy of energy dispersive X-ray spectrometry measurements.