Mp. Petkov et al., Direct evidence of phosphorus-defect complexes in n-type amorphous siliconand hydrogenated amorphous silicon, PHYS REV L, 82(19), 1999, pp. 3819-3822
We use positron annihilation spectroscopy (PAS) to identify the phosphorus-
defect complex (*D-) in n-type hydrogenated amorphous Si (a-Si:H). The posi
trons are attracted and localized at the small open volume associated with
the dangling bond defects. The radiation detected after annihilation gives
a characteristic P signature, regarded as a *D- "fingerprint." Additional e
vidence is obtained from a comparison to P-implanted amorphized Si, as well
as from theoretical calculations. This work lays the foundation for PAS st
udies of impurity-defect related processes in a-Si:H.