The nature of the reverse current transients in large-area nearly ideal p–n junction diodes fabricated on Czochralski silicon substrates is investigated. It is shown that they can be generated by an electrical or optical excitation pulse. A typical nonexponential behavior with time is observed. The best fit is found for a power-law function. The impact of the reverse bias and the temperature on the prefactor and on the exponent will be presented. From the observations, it is concluded that the capture of electrons is a necessary step for the generation of the transients. A discussion of the possible nature of the underlying defects is given, and the implications for practical current–voltage characterization will be discussed. © 1999 American Institute of Physics.