A slow positron beam study of natural and synthetic diamonds

We have depth profiled single crystalline natural type IIA, type IIB and synthetic type IB diamonds with a slow positron beam using Doppler broadening spectroscopy. It was found that the data for all three samples, which differ with respect to defect type and content, could be well described using only a surface and a homogenous bulk component. The bulk positron diffusion lengths measured for these samples were found to be sensitive to the differing defect composition of the samples. q1999 Elsevier Science B.V. All rights reserved