Backscattered electron and X-ray characteristics of tungsten-target surface covered by graphite film

In this study, a method for reducing the number of backscattered electrons by coating a tungsten target with a graphite film is proposed. The backscattered electrons and the characteristics of X-ray emission under varying graphite film thicknesses are analyzed using a Monte Carlo simulation method to evaluate the effectiveness of this approach. The research results indicate that the backscattered electron ratio decreases significantly by using the graphite films. For normal incident electrons with energies of 50 keV, 100 keV, 150 keV and 200 keV, the backscattered electron emission rate drops below 10% when the graphite film thicknesses reach 8 μm, 30 μm, 50 μm and 80 μm, respectively. Compared to an uncoated tungsten target, this method achieves an over 80% reduction in backscattered electron emission. The X-ray emission intensity remains over 60% with the graphite film in place, and the characteristic peaks in the X-ray energy spectrum align with the tungsten target signals, maintaining a uniform angular distribution.