The electrical characterization of He-ion implantation-induced deep levels existing in fully implanted p+n InP junctions isolated by He bombardment is reported in this work. An electron trap located at 0.19 eV below the conduction band and a hole trap located at 0.13 eV above the valence band were detected by deep-level transient spectroscopy (DLTS). Several emission characteristics of these traps were extracted from the correlation between DLTS and the capacitance–voltage transient technique. The experimental determination of trap capture properties was also carried out. In particular, the capture kinetics was found to exhibit a strong temperature dependence for both centers. Two experimental methods—direct recording of capture transients and analysis of DLTS peaks—were used to estimate the capture parameters. Finally, some tentative arguments are proposed in order to correlate the results obtained from the thermal emission and capture measurements. © 1999 American Institute of Physics.