Electrostatic force microscopy study about the hole trap in thin nitride/oxide/semiconductor structure

Abstract

The stoichiometric nitride (SiN1.33) and Si-rich nitride (SiN1.1) are characterized by the conductive atomic force microscopy (c-AFM) and electrostatic force microscopy (EFM). Only in SiN1.1, EFM is capable of resolving the domains of positive charges with ∼10nm radius. However, the phase dependence on the bias elsewhere is similar to that of SiN1.33, supporting electron tunneling. The following c-AFM image also exhibits that the local leakage is found exclusively on SiN1.1. We suggest that the hole injection which breaks the SiSi bond occur in the structure with the voltage, increasing the overall conductance.