Work function mapping of MoOx thin-films for application in electronic devices

André L F Cauduro; Roberto Dos Reis; Gong Chen; Andreas K Schmid; Horst-Günter Rubahn; Morten Madsen

doi:10.1016/j.ultramic.2017.03.025

Work function mapping of MoO_x thin-films for application in electronic devices

Ultramicroscopy. 2017 Dec:183:99-103. doi: 10.1016/j.ultramic.2017.03.025. Epub 2017 Mar 23.

Authors

André L F Cauduro¹, Roberto Dos Reis², Gong Chen², Andreas K Schmid², Horst-Günter Rubahn³, Morten Madsen³

Affiliations

¹ NanoSYD University of Southern Denmark, Alsion 2, 6400-Sønderborg, Denmark. Electronic address: cauduro@mci.sdu.dk.
² National Center for Electron Microscopy, Molecular Foundry, LBNL, Berkeley, CA, 94720, USA.
³ NanoSYD University of Southern Denmark, Alsion 2, 6400-Sønderborg, Denmark.

PMID: 28396081
DOI: 10.1016/j.ultramic.2017.03.025

Abstract

The knowledge of the structural and electronic surface morphology is imperative to fully understand the charge transfer at interfaces of electronic devices, such as in photovoltaic (PV) cells. To this aim, here, we use low-energy electron microscopy to probe the unoccupied states of post-annealed MoO_x thin-films grown in oxygen excess (x∼3.16) and deficient (x∼2.57) environments. 2D work function maps are correlated with the surface topography extracted by mirror electron microscopy (MEM) mode, which show homogenous surface morphology and electronic levels for the specimen with x∼2.57, while it demonstrates nanoaggregates with different work functions on top of flat surface areas for the sample grown with x∼3.16.

Keywords: Leem; MoO(x) thin-films; Morphology; Reactive sputtering; Surface aggregation; Work function.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.