We present the results of the first transient and steady-state photoco
nductivity measurements on self-supporting (19 mu m thick) porous sili
con (PS) sample. The value of the free-carrier photogeneration quantum
efficiency (eta) is discussed together with the mobility-lifetime pro
duct, deduced from transient (mu(D) tau(D)) and steady-state photocurr
ent (mu tau)(ss). Surprisingly (mu tau)(ss) much less than (mu(D) tau(
D)).From very similar spectral dependence and the magnitude of the ste
ady-state photocurrents measured in the sandwich and coplanar geometri
es, we conclude that the ''tissue'' controlled transport in PS is almo
st isotropic.