METAL-SEMICONDUCTOR-METAL PHOTODIODES BASED ON CVD DIAMOND FILMS

We present a study on diamond-based UV photodetectors with lateral met al-semiconductor-metal configuration having the gap between Al electro des of about 5 mu m, similar to the average grain size in diamond film s. Using a simple model for the photocurrent collection, mobility-life time values of diamond layers are derived and compared with available transport data. The spectral response of these devices is also measure d from 1 to about 7 eV, showing the presence of internal photoemission processes in the near infrared region, the existence of localized tra nsitions in the visible and the occurrence of interband transitions ab ove 5 eV, responsible for a large UV photoresponse.