Diamond for VUV sensitive detectors
Diamond (C*) is a wide bandgap semiconductor (Bandgap energy is equal to 5.5 eV, i.e. 220 nm at room temperature), which makes the sensors ‘solar-blind’: insensitive to the solar spectrum below the Earth atmosphere (at sea level) with a good UV/visible response ratio. By using diamond detectors, the number of filters, blocking the unwanted visible radiation, can be reduced and the serious attenuation of the desired UV radiation is minimized. Diamond exhibits several superior properties in comparison to silicon. It has a high charge carrier mobility at room temperature with large breakdown electric field, a low dielectric constant (i.e. low capacitance) and low intrinsic carrier density that makes cooling for noise reduction unnecessary. Its dense tetrahedral structure and stable covalent sp3 bonding between Carbon atoms explain the good radiation hardness of diamond detectors.
