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Title: Thermal chemistry of the Cu-KI5 atomic layer deposition precursor on a copper surface

Abstract

The thermal chemistry of a Cu(I) ketoiminate complex, Cu-KI5, resulting from the modification of the known Air Products CupraSelect{sup ®} copper CVD precursor Cu(hfac)(tmvs) designed to tether the two ligands via an isopropoxide linker, was studied under ultrahigh vacuum on a Cu(110) single-crystal surface by using a combination of temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy. Adsorption at low temperatures was determined to take place via the displacement of the vinyl ligand by the surface. Molecular desorption was seen at 210 K, and the evolution of Cu(II)-KI5{sub 2} was established to take place at 280 K, presumably from a disproportionation reaction that also leads to the deposition of Cu(0). Other sets of desorption products were seen at 150, 250, and 430 K, all containing copper atoms and small organic moieties with molecular masses below 100 amu. The latter TPD peak in particular indicates significant fragmentation of the ligands, likely at the C–N bond that holds the vinylsilane-isopropoxide moiety tethered to the ketoimine fragment, and possibly also at the union between the vinylsilane and the alkoxide linker. The 430 K temperature measured for this chemistry may set an upper limit for clean Cu film deposition, but since reactivity on the surface was also foundmore » to be inhibited at higher surface coverages, it may be delayed to higher temperatures under atomic layer deposition conditions.« less

Authors:
;  [1]
  1. Department of Chemistry, University of California, Riverside, California 92521 (United States)
Publication Date:
OSTI Identifier:
22318079
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 33; Journal Issue: 1; Other Information: (c) 2015 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ADSORPTION; CHEMICAL VAPOR DEPOSITION; COPPER; DESORPTION; MONOCRYSTALS; OXIDATION; SILANES; SURFACES; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Ma, Qiang, and Zaera, Francisco, E-mail: zaera@ucr.edu. Thermal chemistry of the Cu-KI5 atomic layer deposition precursor on a copper surface. United States: N. p., 2015. Web. doi:10.1116/1.4896940.
Ma, Qiang, & Zaera, Francisco, E-mail: zaera@ucr.edu. Thermal chemistry of the Cu-KI5 atomic layer deposition precursor on a copper surface. United States. doi:10.1116/1.4896940.
Ma, Qiang, and Zaera, Francisco, E-mail: zaera@ucr.edu. Thu . "Thermal chemistry of the Cu-KI5 atomic layer deposition precursor on a copper surface". United States. doi:10.1116/1.4896940.
@article{osti_22318079,
title = {Thermal chemistry of the Cu-KI5 atomic layer deposition precursor on a copper surface},
author = {Ma, Qiang and Zaera, Francisco, E-mail: zaera@ucr.edu},
abstractNote = {The thermal chemistry of a Cu(I) ketoiminate complex, Cu-KI5, resulting from the modification of the known Air Products CupraSelect{sup ®} copper CVD precursor Cu(hfac)(tmvs) designed to tether the two ligands via an isopropoxide linker, was studied under ultrahigh vacuum on a Cu(110) single-crystal surface by using a combination of temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy. Adsorption at low temperatures was determined to take place via the displacement of the vinyl ligand by the surface. Molecular desorption was seen at 210 K, and the evolution of Cu(II)-KI5{sub 2} was established to take place at 280 K, presumably from a disproportionation reaction that also leads to the deposition of Cu(0). Other sets of desorption products were seen at 150, 250, and 430 K, all containing copper atoms and small organic moieties with molecular masses below 100 amu. The latter TPD peak in particular indicates significant fragmentation of the ligands, likely at the C–N bond that holds the vinylsilane-isopropoxide moiety tethered to the ketoimine fragment, and possibly also at the union between the vinylsilane and the alkoxide linker. The 430 K temperature measured for this chemistry may set an upper limit for clean Cu film deposition, but since reactivity on the surface was also found to be inhibited at higher surface coverages, it may be delayed to higher temperatures under atomic layer deposition conditions.},
doi = {10.1116/1.4896940},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 1,
volume = 33,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 2015},
month = {Thu Jan 01 00:00:00 EST 2015}
}
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