Investigation of plasma produced by electron pulse ablation
Untersuchung Elektronenpuls-induzierter Plasmen
Short electron pulses with high energy are a very promising tool for the controlled ablation and deposition of materials. The plasmas induced by the electron beam irradiation are distinguished by their high degree of ionization and excitation. A source for pulsed electron beam is the channel spark device. It delivers pulsed high current and self-focused electron beams (about 15 keV, 1 kA, 100 ns). For deposition technology, the plasma beam is the decisive element of the pulsed vapor deposition (PVD) equipment. Hence, the characteristics of the plasma and its dependence on the primary irradiation are of principal importance. The development of the plasma has been characterized by the emitted optical radiation, spectral resolved. Since the energy of the electron beam is not constant during the pulse, the plasma of the channel spark shows strong variations in its temperature and degree of ionization. In the following, spectral-resolved snapshot pictures of the plasma are represented. Cons idering the short pulse times and the small dimensions, a special high-speed camera combining high-temporal, high-spatial and high-spectral resolution has been applied.