Area Selective Deposition of Metals from the Electrical Resistivity of the Substrate.

Hama Nadhom,Robert Boyd,Daniel Lundin,Henrik Pedersen,Polla Rouf

doi:10.1021/acs.jpclett.1c00415

Hama Nadhom, Robert Boyd + Show 3 more

Open Access

https://doi.org/10.1021/acs.jpclett.1c00415

Copy DOI

Journal: Journal of Physical Chemistry Letters	Publication Date: Apr 22, 2021
Citations: 6	License type: CC BY 4.0

Affiliation: Linköping University

Abstract

Area selective deposition (ASD) of films only on desired areas of the substrate opens for less complex fabrication of nanoscaled electronics. We show that a newly developed CVD method, where plasma electrons are used as the reducing agent in deposition of metallic thin films, is inherently area selective from the electrical resistivity of the substrate surface. When depositing iron with the new CVD method, no film is deposited on high-resistivity SiO2 surfaces whereas several hundred nanometers thick iron films are deposited on areas with low resistivity, obtained by adding a thin layer of silver on the SiO2 surface. On the basis of such a scheme, we show how to use the electric resistivity of the substrate surface as an extension of the ASD toolbox for metal-on-metal deposition.

Highlights

Area selective deposition (ASD) of films only on desired areas of the substrate opens for less complex fabrication of nanoscaled electronics
Deposition only on desired areas would avoid the need for patterning and etching steps and allow for bottom-up fabrication of nanoscaled structures. This has motivated research into area selective deposition (ASD) by chemical vapor deposition (CVD) techniques.[1−3] The selectivity in ASD is usually achieved by changing the surface chemistry of the area where film growth is either desired or not desired to control the adsorption of precursor molecules to only specific areas on the substrate
We recently reported a new CVD method for deposition of metallic films where the free electrons in a plasma are used as reducing agents.[10]

Summary

Introduction

Area selective deposition (ASD) of films only on desired areas of the substrate opens for less complex fabrication of nanoscaled electronics. We recently reported a new CVD method for deposition of metallic films where the free electrons in a plasma are used as reducing agents.[10] Because the method draws an electron current from the plasma to an electrically biased substrate, a conducting surface is needed to close the electric circuit allowing the electron current to flow from the plasma discharge to the bias power supply without any charge buildup.

Results

Conclusion