While sensitization of the photoconductivity, i.e., the increase of the majority carrier lifetime by the addition of recombination centers, is known for many years, there was no evidence or suggestion for the corresponding sensitization of the minority carrier lifetime. In this letter, we present experimental evidence for the existence of such an effect in device quality undoped hydrogenated amorphous silicon films. We propose possible scenarios that can yield the observed effect and mention the possible benefits of the minority carrier sensitization for the improvement of bipolar optoelectronic devices made of this material. ©1998 American Institute of Physics.