Energy-resolving carbon resistance probes for plasma edge characterization

The resistance increase in thin carbon films caused by energetic particle bombardment was developed into the carbon resistance probe, to measure the energy and flux of particles at the edge of a plasma. This probe was calibrated by ion implantation of hydrogen and deuterium with energies from 20 to 1600 eV. Sensitivity to particles with energies as low as 30 eV was demonstrated. Calibrations are also presented for thin-layer resistance probes, a configuration in which energy resolution is obtained using carbon films and ranging overlayers comparable in thickness to the range of the particles. The results show that thin-layer probes can be used to measure the particle energies and fluxes typically encountered at the first wall of a Tokamak.