The effect of doping on the steady-state photoconductivity σpof hydrogenated amorphous silicon (a-Si:H) down to temperatures of 4·2 K has been studied. Phosphorus doping up to 10−2PH3/SiH4does not essentially change σp/eG, the photoconductivity normalized by the photocharge generation rateeGeither at lowTwhere σp/eGis constant, or between 30K <T< 50K where it rises withT.Boron doping on the other hand causes σp/eGat low T to decrease significantly and to rise withTat a higher temperature. This effect of boron doping is not related to the defect density or to the sign of the charge carriers. We tentatively attribute this effect to a heterogeneous morphology that is associated with boron doping.