Determination of localized states in porous silicon

We determined the density of state distribution near the Fermi level in por ous silicon from the analysis of the current-voltage (J-V) and the current- thickness (J-T) characteristics in the space-charge-limited-current (SCLC) regime. The distribution exhibits a minimum density at the Fermi level whic h is similar to the U-shape-trap-distribution observed in crystalline Si-Si O2 interface or in amorphous Si. Theoretical analysis well explains both th e J-V and the J-T characteristics, which implies that the current flow is e ntirely controlled by localized states situated at the quasi-Fermi level. ( C) 1999 Published by Elsevier Science B.V. All rights reserved.