Electrical properties and formation mechanism of porous silicon carbide

Abstract

Variation of the preparation conditions of porous silicon carbide is shown to have a strong effect on the structural and electrical properties of the material obtained. A correlation has been observed between the fiber size and resistivity of porous SiC, a decrease of fiber size results in a semi-insulating material due to Fermi-level pinning to surface states. A model is proposed for the mechanism of fiber size self-regulation responsible for the porous material formation. The model relates the blocking of the fiber dissolution process to the increase of resistivity in a thin fiber due to Fermi-level pinning. We suggest that the Fermi-level pinning model is also applicable to the formation mechanism of porous silicon.