Features of electroforming in open 'sandwich'-structures Si-SiO_2-W for silicon of different types of conductivity

摘要

The results of experiments on research of electroforming processes in open "sandwich"-structures Si-SiO_2-W (silicon - silicon dioxide - tungsten) with thickness of silicon dioxide about 20 nm are shown. The basic distinction for silicon of p-and n-types conductivity is marked: in the first case usual for electroforming N-type current-voltage characteristic and in the second S-type curve typical for electric breakdown with thermal instability are observed. The mechanisms of processes are discussed. The marked distinction is connected with the fact that in structures n-Si-SiO_2-W the current is transported basically by electrons which dissociative attachment to molecules on a surface of an insulating slit leads to their destruction and conductive phase particles formation from them. In a current through structures p-Si-SiO_2-W the electrons prevail only at initial moments of electroforming, in process of conductive medium accumulation their share falls by one - two orders, and the current is transported basically by holes, which cannot participate during formation of conductive phase particles.