Ra. Dunlap et al., A DOPPLER BROADENING POSITRON-ANNIHILATION TECHNIQUE FOR THE STUDY OFDEFECTS IN BULK SAMPLES, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 108(3), 1996, pp. 339-342
A Doppler broadening positron annihilation technique which allows for
the study of near surface defects in bulk samples is described. The me
thod is capable of observing changes in the homogeneous bulk defect co
ncentration in a sample acid is also able to characterize spatially lo
calized near-surface defects in bulk materials with a resolution of ab
out 1 mm. The applicability of this method is demonstrated by measurem
ents on a sample of polycrystalline aluminum into which defects have b
een introduced by mechanical deformation. Isochronal annealing studies
have been used to characterize the defect recovery in this material a
nd are compared with results of conventional Doppler broadening measur
ements.