Positron Annihilation Spectroscopy (PAS) has been employed to study the defect distributions of B-11-, N-14-, and Al-27-implanted epitaxial 4H-SiC. At least three types of defects are needed to account for the PAS data and the Doppler Broadening line shape parameters for two of the defects have been determined to (S/S-bulk, W/W-bulk) (1.060, 0.850) and (1.070, 0.820), respectively. The extension of the defect profiles, extracted from the PAS spectra, correlate well to the depth of the deepest channeled ions as determined by secondary ion mass spectrometry. The positron diffusion coefficient in the un-implanted material has been determined to D-bulk(+) = 7 cm(2)/s.