Dependence of Sputtering Coefficient on Energy and Incidence Angle of Bombarding Particles. Energy Spectrum and Average Energy of Sputtered Particles by the Example of a Tungsten Target

The work provides an overview of the functional dependencies (formulas) for describing the properties of atomic particles sputtered during ion bombardment of the surface of a solid body. The dependence of sputtering coefficients on the energy and angle of incidence of the bombarding particle is considered. The energy spectra and average energies of sputtered particles are presented. Using the example of a target made of tungsten and hydrogen isotopes as projectiles, formulas for calculating the quantities under consideration are proposed. These data are necessary to estimate the entry of sputtered tungsten atoms as an impurity into a hot plasma using transport codes. When the tungsten impurity concentration is more than critical, it is impossible to carry out a controlled thermonuclear reaction with the planned energy output in the ITER tokamak reactor. Sputtering coefficients also play an important role in modeling the entry of impurities into plasma installations as a result of the interaction of hydrogen fuel atoms with the materials of the divertor and the first wall.