beta-radiation detected nuclear magnetic resonance (beta-NMR) measurem
ents of B-12 occupying sites with noncubic surroundings after implanta
tion into Si have been extended from p-type to moderately doped n-type
material. The quadrupole split signals observed in both materials ind
icate the existence of the same interstitial related boron defect but
with lower thermal stability in n-type Si.