RADIATION DAMAGE EFFECTS ON OPTICAL, ELECTRICAL, AND THERMOPHYSICAL PROPERTIES OF CVD DIAMOND FILMS

摘要

Raman and IR spectroscopy and thermal conductivity were employed to investigate the effects of simultaneous vacuum annealing on defect transformation processes in diamonds irradiated by fast neutrons and nanocrystalline diamond films (DF) implanted with O or P ions. A correlation between the thermal conductivity at room temperature and the absorption coefficient near 13 μm was found in diamonds irradiated by neutron fluence 2·10~(19) cm~(-2). It was found that two-phonon absorption in diamond IR spectra was sensitive to destruction of long-range ordering in the diamond crystal lattice. An absorption band with a shape characteristic of localized centers in the band gap (activation energy ～0.25 eV) was identified in IR spectra of DF irradiated by neutrons and annealed at temperatures <900℃. It was shown that the optical and transport properties of the studied radiation-damaged DF were determined by multi-vacancy complexes and inclusions of a non-diamond phase.