EFFECT OF NITROGEN INCORPORATION ON ELECTRICAL-PROPERTIES OF BORON-DOPED DIAMOND FILMS

The effect of a small amount of nitrogen incorporated in chemical vapo r deposited diamond films on their electrical properties was studied. Upgrading the purity of CH4 gas from the conventional ultra-high purit y to the grade with no detection of nitrogen resulted in improvement o f electrical properties of the boron-doped homoepitaxial diamond films ; the Hall mobility was increased by 4.3 times at the room temperature . Decrease in nitrogen concentration in the diamond films was confirme d by investigating the 2.16 eV center of cathodoluminescence induced b y ion beam irradiation and subsequent annealing. (C) 1997 American Ins titute of Physics.