Metal Organic interfaces at the nanoscale

TL;DR

This paper uses ballistic electron emission microscopy to study Ag-PPP metal-organic interfaces at the nanoscale, revealing inhomogeneous charge injection and barrier variations that impact electronic transport understanding.

Contribution

First application of BEEM to metal-organic interfaces, providing nanoscale insights into charge injection inhomogeneities and barrier transmission.

Findings

Nanometer-scale injection inhomogeneities observed

Schottky barrier variations linked to electronic origin

Transmission function aligns with theoretical models

Abstract

In this work, we present an investigation of the Ag-PPP (polyparaphenylene) interface using ballistic electron emission microscopy. Our work is the first successful application of the BEEM technique to metal-organic interfaces. We observe nanometer scale injection inhomogeneities. They have an electronic origin, since we find corresponding Schottky barrier variations. We also determine the transmission function of Ag-PPP interface and find that it agrees qualitatively with the theoretical calculations for a metal-phenyl ring interface. We conclude that charge transport across inhomogeneous barriers needs to be considered for understanding electronic transport across metal-organic interfaces and organic device characteristics.