Rapid three-dimensional imaging of defect distributions using a high-intensity positron microbeam

Oshima, N.; Suzuki, R.; Ohdaira, T.; Kinomura, A.; Narumi, T.; Uedono, A.; Fujinami, M.
May 2009
Applied Physics Letters;5/11/2009, Vol. 94 Issue 19, p194104
Academic Journal
An intense positron microbeam generated by an electron accelerator has been developed for obtaining three-dimensional positron lifetime mappings in a sample to permit visual evaluation of defect distributions. The beam diameter at the sample was 80–100 μm. The counting rate of the positron annihilation γ rays used to measure positron lifetime was as large as 3×103 s-1. Three-dimensional imaging was demonstrated of positron lifetimes in a SiO2 sample, which was irradiated with ion beams through a mesh mask. The time to obtain a single image (3500 pixels for an area of 2.5×3.5 mm2) was 0.5–1 h.


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