Carrier transport in graphite/Si3N4-nanobelt/PtIr Schottky barrier diodes

摘要

Understanding the roles of contacts and interfaces between metals and semiconductors is critically important for exploring nanostructure-based nanodevices. The present study shed some light on the dominated mechanism of size-dependent carrier transfer in the Schottky barrier diodes configured by the Pt-Ir/SiN-nanobelt/graphite (metal-semiconductor-metal (MSM)) sandwiched structure via a conductive atomic force microscopy using nanobelts with various thicknesses. The observed I-V behaviors suggested that the charge transports under the low and high biases were dominated by the reverse-biased Schottky barrier and space-charge-limited current (SCLC), respectively. The intermediate region between the low and high biases presented the transition between the Ohmic and SCLC behaviors, in which the ≡Si and =N dangling bonds acted as the defects within the SiN nanobelt surface are predominant in the charge transfer.