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Title: Precursor dependent nucleation and growth of ruthenium films during chemical vapor deposition

Abstract

Nucleation and film growth characteristics are reported during chemical vapor deposition of Ru on SiO{sub 2} using triruthenium dodecacarbonyl [Ru{sub 3}(CO){sub 12}] and ruthenium bis(di-t-butylacetamidinate) dicarbonyl [Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2}]. Films grown from Ru{sub 3}(CO){sub 12} follow the three dimensional (3D) Volmer–Weber growth mode. In contrast, films grown from Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2} follow the pseudo-layer-by-layer growth mode with two dimensional wetting layer islands forming before 3D particle growth is observed on the islands. A relationship between free isolated hydroxyl [(Si-OH){sub i}] group density and Ru nucleation density is found for Ru{sub 3}(CO){sub 12} and is associated with (Si-OH){sub i} acting as the reaction sites for activation of Ru{sub 3}(CO){sub 12} and in turn generating an adjustable adatom concentration. Carbon monoxide and ammonia addition to the gas phase during film growth from Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2} lead to smoother films by inducing surface reconstructions during the 3D phase of pseudo-layer-by-layer growth; these gases also lead to films with lower resistivity and lower crystalline character.

Authors:
;  [1]
  1. McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E Dean Keeton St. Stop C0400, Austin, Texas 78712 (United States)
Publication Date:
OSTI Identifier:
22592880
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 34; Journal Issue: 4; Other Information: (c) 2016 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; AMMONIA; CARBON MONOXIDE; CHEMICAL VAPOR DEPOSITION; CONCENTRATION RATIO; DENSITY; FILMS; HYDROXIDES; LAYERS; NUCLEATION; RUTHENIUM; SILICA; SILICON OXIDES; SURFACES; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS; VAPORS

Citation Formats

Liao, Wen, and Ekerdt, John G., E-mail: ekerdt@utexas.edu. Precursor dependent nucleation and growth of ruthenium films during chemical vapor deposition. United States: N. p., 2016. Web. doi:10.1116/1.4953882.
Liao, Wen, & Ekerdt, John G., E-mail: ekerdt@utexas.edu. Precursor dependent nucleation and growth of ruthenium films during chemical vapor deposition. United States. doi:10.1116/1.4953882.
Liao, Wen, and Ekerdt, John G., E-mail: ekerdt@utexas.edu. Fri . "Precursor dependent nucleation and growth of ruthenium films during chemical vapor deposition". United States. doi:10.1116/1.4953882.
@article{osti_22592880,
title = {Precursor dependent nucleation and growth of ruthenium films during chemical vapor deposition},
author = {Liao, Wen and Ekerdt, John G., E-mail: ekerdt@utexas.edu},
abstractNote = {Nucleation and film growth characteristics are reported during chemical vapor deposition of Ru on SiO{sub 2} using triruthenium dodecacarbonyl [Ru{sub 3}(CO){sub 12}] and ruthenium bis(di-t-butylacetamidinate) dicarbonyl [Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2}]. Films grown from Ru{sub 3}(CO){sub 12} follow the three dimensional (3D) Volmer–Weber growth mode. In contrast, films grown from Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2} follow the pseudo-layer-by-layer growth mode with two dimensional wetting layer islands forming before 3D particle growth is observed on the islands. A relationship between free isolated hydroxyl [(Si-OH){sub i}] group density and Ru nucleation density is found for Ru{sub 3}(CO){sub 12} and is associated with (Si-OH){sub i} acting as the reaction sites for activation of Ru{sub 3}(CO){sub 12} and in turn generating an adjustable adatom concentration. Carbon monoxide and ammonia addition to the gas phase during film growth from Ru({sup t}Bu-Me-amd){sub 2}(CO){sub 2} lead to smoother films by inducing surface reconstructions during the 3D phase of pseudo-layer-by-layer growth; these gases also lead to films with lower resistivity and lower crystalline character.},
doi = {10.1116/1.4953882},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 4,
volume = 34,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
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