IMAGING OF BORON DOPANT IN HIGHLY ORIENTED DIAMOND FILMS BY CATHODOLUMINESCENCE IN A TRANSMISSION ELECTRON-MICROSCOPE

Boron-doped, highly oriented, (100) textured diamond films have been examined by cathodoluminescence in a transmission electron microscope to assess the distribution of the defects and boron dopant within the films. Dislocation-related luminescence, which is believed to be unrelated to boron, was found to originate inhomogeneously in the films, from dislocations within single grains and at grain boundaries. Luminescence from donor-acceptor pairs involving boron was imaged with submicron spatial resolution to show that boron dopant is uniformly distributed from grain to grain and within individual grains, in these diamond films. The dislocation density in undoped films grown under similar conditions was found to be much lower than in B-doped films, suggesting that the introduction of B not only results in its incorporation as a dopant, but also gives rise to dislocations.