Probing the Conductance and Microstructure Heterogeneity of Si3N4/TiC-Based Nanocomposite at the Nanoscale by Scanning Impedance Microscopy

Authors


Author to whom correspondence should be addressed. e-mails: hcliu@mail.ncku.edu.tw and hcliu@alumni.stanford.edu

Abstract

This study presents the results of atomic force microscopy (AFM)-localized impedance measurements within Si3N4/glassy phase/TiC heterogeneous nanostructures. The three phases show significant differences in the charge-transfer resistance and interface capacitance values detected on the plasma-etching surface by an ultrasharp AFM, and these characteristics are helpful to understand the sintering behavior in spark plasma sintering. The effect of an electrical field may induce localized Joule heating on conductive nano-TiC embedded in the Si3N4-based matrix. The glassy phase doped with Ti and C, as observed by transmission electron microscopy, may promote electrowetting, leading to enhanced densification in the insulating/conductive ceramic nanocomposite system.

Ancillary