RESUMEN
Faraday cup fast ion loss detectors have attractive properties for fusion applications, as they can measure wide ranges of energy, are intrinsically neutron-hardened, and can be packaged in very small form factors. The latter allows them to be installed as arrays, offering opportunities to decouple fast ion loss location and magnitude in fully three-dimensional magnetic fields. In this work, we characterize the layer thicknesses of detector prototypes using spectral reflectance measurements, confocal laser scanning microscopy, as well as raster electron microscopy with a focused ion beam. We find that the measured layer thicknesses agree well enough with the specification to allow for accurate measurements. The as-manufactured heights are on the high side, increasing reliability. The data presented here further sets the basis for future optimizations in manufacturing.
RESUMEN
The development and testing of a Faraday cup fast-ion loss detector capable of measuring sub 100 keV particles is documented. Such measurement capabilities play an important role in the assessment of particle confinement of nuclear fusion experiments. The detector is manufactured using thin-film deposition techniques, building upon previous work using discrete foils. This new manufacturing method allows the form factor of the sensor to become that of essentially a microchip. Analysis of the diagnostic response is performed using Monte-Carlo particle simulations. These simulations show peaks in the detector response at 40 and 70 keV. The sensor is then tested in a tunable linear accelerator capable of accelerating protons from 20 to 120 keV. The detector response was found to be well matched to simulations. Improvements to the design to facilitate robustness are discussed.