Recent IBIC measurements on epitaxial CVD diamond

Abstract Frontal IBIC (Ion Beam Induced Current) mesurements have been carried out on new single crystal epitaxial CVD diamond. The sample consists of about 100 μm synthetic diamond grown by microwave CVD on a 300 μm thick, low cost, HPHT diamond substrate (see Balducci et al. – this conference). Both proton and alpha microbeams of energies 3 and 4.5 MeV have been used, with a beam diameter spot of about 1.5–3 μm. Scanned areas varied from 450 μm × 450 μm down to 150 μm × 150 μm and the homogeneity of charge collection efficiency (cce) was suitably monitored. At voltage bias of 80–100 V, the average cce was in the range 42–50%. Depending on the scanned surface area and on the beam type, energy resolutions FWHM from 1.3% to 4.1% FWHM have been obtained, even at counting rates as high as 700 cps