Effects of thermal treatment on optically active vacancy defects in CVD diamonds

Abstract In this paper we report on the preliminary results obtained in as-grown and annealed CVD diamond with positron annihilation spectroscopy. We observe clustering of as-grown vacancy defects in annealing above 1400 ∘ C . The optical activity of the vacancy defects is studied by shining monochromatic light in the visible range during the positron measurements.