Characterisation of SiC photo-detectors for solar UV radiation monitoring

Silicon carbide has a potential for solar UV radiation monitoring: extremely resistant to UV radiation damage, nearly-blind to visible and infrared radiation and less sensitive to temperature variations than standard radiometric systems. A radiometer composed by three SiC photodiodes has been designed, manufactured and tested under solar radiation. Two photodiodes are equipped with filters in the UVB (280-315 nm) and UVA (315-400 nm) ranges while a third is filtered to match the erythemal action spectrum. UVA, UVB components of the solar radiation as well as UV index (UVI) at the earth's surface have been determined in two site positions in Tuscany, Italy. Data as a function of day-light allowed us to evaluate total optical thickness for UVA and UVB: τUVA=0.46 and τUVB=1.8. UVI values measured during the year well compares with computed ones used for weather forecast procedures.