Transient current measurements of porous layers on p+-type substrates were used to characterize the surface defects of porous material; that is, defects which were located at the interface between porous material and a thin layer of native oxide. An energy level which was located near to the mid-gap (efficient radiative lifetime killer), and a trap concentration which was in close agreement with the number of trivalent Si defects (as measured by means of electron spin resonance) were deduced.

C.Cadet, D.Deresmes, D.Vuillaume, D.Stievenard, A.Grosman, C.Ortega, J.Siejka, H.J.Von Bardeleben: Materials Science Forum, 1994, 143-147, 1475-80