Hall measurements are a common method to determine the majority charge carrier diffusion constant. But the diffusion constant of the minority carriers D-n, the more interesting parameter in photovoltaics, is rather hard to detect. In this paper we introduce a method to determine D-n locally resolved and mapped in two dimensions. For that purpose the local diffusion length L-diff, which can be calculated from LBIC (laser beam induced current) measurements, has been combined with the local bulk lifetime tau(b) received by mu-PCD (microwave-detected photo conductance decay) measurements. We evaluated the diffusion constants of the minority charge carriers D-n for different p-type silicon materials with a resolution of 100 mum, The measurements were carried out on solar cells before and after remote plasma hydrogen passivation in order to get an impression of the diffusion constant dependency on hydrogen incorporation. (C) 2002 Elsevier Science B.V. All rights reserved.