Thermoluminescent behaviour of diamond films subjected to UV irradiation

The thermoluminescent behaviour of diamond films subjected to UV irradiatio n was studied by using an UV lamp of 254 nm wavelength. The UV irradiation was achieved by placing the samples 15 cm away from an UV source for differ ent periods. The thermoluminescent signal was integrated from 0 to 350 degr ees C at a linear heating rate of 10 degrees C/s in a N-2 atmosphere. The c orresponding luminescence spectra show an excitation band centered at 450 n m while the emission band is centered around 500 nm at room temperature. Th e diamond films were synthesized on molybdenum substrates by the combustion flame technique and characterized by Raman spectroscopy and scanning elect ron microscopy.