PHOSPHORUS INCORPORATION IN PLASMA-DEPOSITED DIAMOND FILMS

Phosphorus-doped polycrystalline and homoepitaxial diamond films were grown using both microwave and dc plasma assisted chemical vapor depos ition. P incorporation was quantified using secondary ion mass spectro metry, and was approximately ten times greater for polycrystalline fil ms deposited using dc plasmas compared to microwave plasmas. For micro wave-assisted growth, P incorporation was approximately ten times grea ter in polycrystalline than homoepitaxial films. These effects appear to be due to preferential incorporation at grain boundaries, since hig her levels of P are measured in samples with smaller grains. The films were highly electrically resistive, with conductivities of 10(-10)-10 (-9)/OMEGA cm at room temperature.