Ultrafast transient reflecting grating (TRG) spectroscopy was utilized for defect analysis in the surface region of ion-implanted silicon for the implantation range from 10(11) to 10(15) cm(-2). To deduce signals due to trapped carriers at defect states, the TRG spectra at the delay time of 30 ps were measured because ultrafast carrier dynamics such as many-body recombination had finished before the delay time. According to the dose quantity, the peak of the interband transition was affected and also defect-related transitions emerged. Using this technique, implantation damage can be detected for samples with their dose larger than 10(12) cm(-2). It was proposed that TRG spectroscopy can be used as a novel analytical method for characterizing defects in the surface region of semiconductors. (C) 2003 American Institute of Physics.