Diffusion-induced time resolved microwave conductivity is a method for transverse transport studies in semiconductors deposited on crystalline silicon. In this paper, by measuring layers with different thickness, we show that the transit time of carriers is controlled by diffusion. Moreover, measurements as a function of flux allow us to deduce the diffusion coefficients of electrons and holes and to separate surface and bulk recombination, depending on transport being in unipolar or bipolar regime. We finally compare the diffusion coefficient deduced from this method with TRMC mobility.