C-Axis-Oriented Ru Thin Films Prepared by Sputtering in Ar and O<sub>2</sub> Gas Mixture

Abe, Yoshio; Kaga, Y.; Kawamura, Midori; Sasaki, Katsutaka

doi:10.1143/jjap.40.6956

Cited by 12 publications

(10 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The success of this experiment confirmed that the deposition of metallic ruthenium is possible even under conditions using a small amount of an oxidant such as oxygen. Furthermore, the XRD pattern showed an enhanced (002) signal intensity, which is consistent with the characteristics of C -axis-oriented Ru thin films that were deposited on glass substrates using dc magnetron sputtering in a mixture of argon and ambient O 2 . This is attributed to the fact that the (001) crystallographic planes have the closest interplanar spacing and that the adsorbed oxygen atom may decrease the surface free energy and enhance the (001) preferential orientation.…”

Section: Resultssupporting

confidence: 77%

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

et al. 2003

View full text Add to dashboard Cite

The synthesis and characterization of ruthenium complexes [Ru(CO)2(amak)2] and [Ru(COD)(amak)2] (where COD = 1,4-cyclooctadiene) are reported, where (amak)H is an abbreviation for a series of fluorinated amino alcohol ligands with formula HOC(CF3)2CH2NHR, where R = H, Me, Et, and (CH2)2OMe. The carbonyl complex [Ru(CO)2(amak1)2] (1 with R = H) was examined by X-ray diffraction (XRD), showing an octahedral coordination for the Ru atom, with two cis carbonyl ligands and two amino alkoxide chelates. For the COD complexes [Ru(COD)(amak1)2] (3 with R = H) and [Ru(COD)(amak3)2] (4 with R = Et), the structural analysis indicated the existence of two distinct spatial arrangements of amino alkoxide chelates with respect to the coordinated COD ligand, depending on the type of amino group selected. All of these complexes show good volatility and thermal stability. For complexes 2 and 4, which are more volatile and low-melting, chemical vapor deposition (CVD) experiments were conducted at temperatures of 325−425 °C, using both H2 and a mixture of 2% O2 in argon as the carrier gas. Scanning electron micrographs (SEMs) were taken to reveal the surface morphologies; these Ru thin films were found to contain low levels of carbon and oxygen impurities, as measured by X-ray photoelectron spectroscopy (XPS).

show abstract

Section: Resultssupporting

confidence: 77%

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

et al. 2003

View full text Add to dashboard Cite

show abstract

“…This unusual characteristic is consistent with the presence of C-axis ori- on glass substrates using dc magnetron sputtering in a mixture of argon and ambient O 2 . [25] The formation of such structure can be attributed to the smaller inter-planar spacing of the (001) crystallographic planes, on which unidirectional thin film growth is more favorable due to the lower surface free energy thus leading to the (001) preferential orientation. For these thin films the XPS analysis detected a reduced amount of carbon (1 %) and oxygen (2 %).…”

Section: Deposition Of Ru Metalmentioning

confidence: 99%

Synthesis and Characterization of Tris(β‐ketoiminato)ruthenium(III) Complexes: Potential Precursors for CVD of Ru and RuO₂ Thin Films

Chou¹,

Lai²,

Chen³

et al. 2004

Chemical Vapor Deposition

View full text Add to dashboard Cite

The synthesis and characterization of Ru III metal complexes [Ru(keim1) 3 ] (1) and [Ru(keim2) 3 ] (2) are reported, where (keim)H is an abbreviation for the fluorinated ketoimine ligands with formula HOC(CF 3 )=CHCR=NMe; (keim1)H with R = Me and (keim2)H with R = CF 3 . These newly synthesized complexes were characterized by spectroscopic methods, while the second complex, 2, was further examined by single-crystal X-ray diffraction (XRD), revealing an octahedral coordination for the Ru cation, with three ketoiminate arranged in a mer-configuration, a consequence of the enhanced steric interaction between ligands. Moreover, both Ru metal complexes show good volatility and thermal stability. CVD experiments were conducted using these complexes at temperatures of 325±450 C. The Ru metal and RuO 2 thin films on silicon wafers were successfully obtained using either a mixture of 2 % O 2 in argon or pure O 2 as the carrier gas, respectively. Our result shows that a 2 % O 2 concentration induces the formation of Ru metal, while that only complex 1 gives formation of a columnar RuO 2 phase upon switching to pure O 2 as the CVD carrier gas. Scanning electron microscopy (SEM) images were taken to reveal surface morphologies, while X-ray photoelectron spectroscopy (XPS) and XRD were utilized to access their atomic composition as well as the intrinsic packing of the as-deposited thin film materials.

show abstract

“…In accordance with this hypothesis, a high quality c-axis oriented Ru thin film was deposited on a glass substrate using dc magnetron sputtering. 19 The deposition of Ru metal thin films was next conducted with complex (1) as the CVD precursor and a mixture of 2% oxygen in argon as the alternative carrier gas. The selection of this deposition parameter was encouraged by a recent report that the oxygen could enhance the oxidative ligand decomposition, resulting in metal deposition at lower temperatures, and then affecting the phase and other physical properties of the as-deposited thin film.…”

Section: Deposition Of Ru Metal Thin Filmsmentioning

confidence: 99%

Deposition of Ru and RuO2 thin films employing dicarbonyl bis-diketonate ruthenium complexes as CVD source reagents

et al. 2003

View full text Add to dashboard Cite

Reaction of Ru 3 (CO) 12 with 6 eq. of b-diketone ligands (hfac)H, (tmhd)H, (acac)H and (tfac)H at 160-170 uC in a hydrocarbon solvent (pentane or hexane) affords the diketonate complexes [Ru(CO) 2 (hfac) 2 ] (1), [Ru(CO) 2 (tmhd) 2 ] (2), [Ru(CO) 2 (acac) 2 ] (3) and [Ru(CO) 2 (tfac) 2 ] (4) in high yields. These ruthenium complexes were characterized by spectroscopic methods; a single crystal X-ray diffraction study was carried out on one isomer of the tfac complex (4a), revealing an octahedral coordination geometry with two CO ligands located at cis-positions and with the CF 3 groups of the b-diketonate ligands trans to the CO ligands. Thermogravimetric analysis of complex (1) showed an enhanced volatility compared to the parent acac complex (3), attributed to the CF 3 group reducing intermolecular attraction. Employing complexes (1) and (2) as CVD source reagents, ruthenium thin films can be deposited at temperatures of 350 uC-450 uC under an H 2 atmosphere or at temperatures of 275 uC-400 uC using a 2% mixture of O 2 in argon as carrier gas. For deposition carried out using complex (1) and under 100% O 2 atmosphere, RuO 2 thin films with a preferred (200) orientation were obtained. The as-deposited thin films were characterized by surface and physical analytical techniques, such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction analysis (XRD) and four-point probe measurement.Ruthenium-containing thin films show great promise for fabricating bottom electrodes or non-corrosive diffusion barriers for next generation, tantalum oxide (Ta 2 O 5 ), barium strontium titanate (BST) and lead zirconate titanate (PZT) based nonvolatile random access memory (RAM) devices.1 The advantages of ruthenium over other conducting materials include: lower resistivity, good etching ability, good barrier properties against oxygen diffusion, high resistance against capacitor shorting due to the formation of hillocks, severe polarization fatigue and aging.2 Moreover, its oxide phase, RuO 2 , which crystallizes in the rutile structure, belongs to a class of conductive oxide materials that exhibit excellent chemical stability at higher temperatures in O 2 ambient. These combined characteristics make RuO 2 an idea candidate for the fabrication of diffusion barriers for contact metallizations in very large scale integration (VLSI) applications, buffer layers of high T c superconducting films on silicon, and electrodes of ferroelectric thin films.Chemical vapor deposition (CVD) has received more attention in recent years, particularly in depositing these ruthenium-containing thin films, for its obvious capability of alleviating problems associated with the physical vapor deposition or sputtering process, such as low conformal coverage, poor crystallinity, and high stress level. As a result, several Ru metal-containing complexes have been examined as potential CVD precursors, including (a) ruthenocene 3 and its alkyl substituted derivatives such as Ru (C 5 hfb~hexafluoro-2-butyne, and Ru 3 ...

show abstract

C-Axis-Oriented Ru Thin Films Prepared by Sputtering in Ar and O₂ Gas Mixture

Cited by 12 publications

References 15 publications

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

Synthesis and Characterization of Tris(β‐ketoiminato)ruthenium(III) Complexes: Potential Precursors for CVD of Ru and RuO₂ Thin Films

Deposition of Ru and RuO2 thin films employing dicarbonyl bis-diketonate ruthenium complexes as CVD source reagents

Contact Info

Product

Resources

About

C-Axis-Oriented Ru Thin Films Prepared by Sputtering in Ar and O2 Gas Mixture

Cited by 12 publications

References 15 publications

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

Synthesis and Characterization of Ruthenium Complexes with Two Fluorinated Amino Alkoxide Chelates. The Quest To Design Suitable MOCVD Source Reagents

Synthesis and Characterization of Tris(β‐ketoiminato)ruthenium(III) Complexes: Potential Precursors for CVD of Ru and RuO2 Thin Films

Deposition of Ru and RuO2 thin films employing dicarbonyl bis-diketonate ruthenium complexes as CVD source reagents

Contact Info

Product

Resources

About

C-Axis-Oriented Ru Thin Films Prepared by Sputtering in Ar and O₂ Gas Mixture

Synthesis and Characterization of Tris(β‐ketoiminato)ruthenium(III) Complexes: Potential Precursors for CVD of Ru and RuO₂ Thin Films