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The growth of ultrathin (<5 nm) Ru-doped Cu2O films deposited on SiO2 by atomic layer deposition (ALD) and Cu films by subsequent reduction of the Cu2O using HCO2H or CO is reported. Ru-doped Cu2O has been deposited by a mixture of 16: 99 mol. % of [(nBu3P)2Cu(acac)] as Cu precursor and 17: 1 mol. % of [Ru(η5-C7H11)(η5-C5H4SiMe3)] as Ru precursor. The catalytic amount of Ru precursor was to support low temperature reduction of Cu2O to metallic Cu by formic acid (HCO2H) on arbitrary substrate. In situ x-ray photoelectron spectroscopy investigations of the Cu2O ALD film indicated nearly 1 at. % of carbon contamination and a phosphorous contamination below the detection limit after sputter cleaning. Systematic investigations of the reduction of Ru-doped Cu2O to metallic Cu by HCO2H or CO as reducing agents are described. Following the ALD of 3.0 nm Cu2O, the ultrathin films are reduced between 100 and 160 °C. The use of HCO2H at 110 °C enabled the reduction of around 90% Cu2O. HCO2H is found to be very effective in the removal of oxygen from Ru-doped Cu2O films with 2.5-4.7 nm thickness. In contrast, CO was effective for the removal of oxygen from the Cu2O films only below 3.0 nm at 145 °C. Root mean square surface roughness of 0.4±0.1 nm was observed from atomic force microscopy (AFM) investigations after the ALD of Cu2O, followed by the subsequent reduction of 3.0 nm Cu2O using either HCO2H at 110 °C or CO at 145 °C on SiO2. Furthermore, ex situ low energy ion scattering and AFM investigations confirmed that the Cu2O film after ALD and Cu films after subsequent reduction was continuous on the SiO2 substrate. [ABSTRACT FROM AUTHOR]

Silver(I) dithiocarbamates [Ag{S2CNR(C2H4OH)}] (3a, R = Me; 3b, R = Bu) were accessible by the reaction of AgNO3 with K{S2CNR(C2H4OH)} (2a, R = Me; 2b, R = Bu). Alternatively, 3b could be prepared by the condensation of CS2 and Ag2O with NHBu(C2H4OH) (1b). The thermal behavior of 3 was studied by thermogravimetric (TG) analysis. A two-step decomposition process leads to the formation of α-Ag2S, as evidenced by X-ray powder diffraction studies. A decomposition mechanism of 3a to form Ag2S through the release of 3-methyloxazolidine-2-thione is discussed based on TG-MS, GC-MS, and NMR experiments. Because of the better solubility of 3b, this complex was tested for Ag2S spin-coating deposition studies on different substrates (SiO2/Si, TiN/SiO2/ Si, glass) with subsequent annealing at 450 °C under a N2 atmosphere. Film thickness, composition, and morphology of the as-deposited films were determined by XRD, SEM, energy- dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, which showed the formation of 200 nm thick, conformal, adherent, monoclinic α-Ag2S layers. [ABSTRACT FROM AUTHOR]

Consecutive synthesis methodologies for the preparation of a series of trimethylsilyl and tert-butyl-substituted ruthenocenes of the type Ru(η5-C5H3R1R2)(η5-C5H3R3R4) ( 2, R1 = SiMe3, R2 = R3 = R4 = H; 3, R1 = R3 = SiMe3, R2 = R4 = H; 4, R1 = R2 = R3 = SiMe3, R4 = H; 5, R1 = R2 = R3 = R4 = SiMe3; 6, R1 = R3 = tBu, R2 = R4 = H; 7, R1 = R3 = tBu, R2 = SiMe3, R4 = H; 8, R1 = R3 = tBu, R2 = R4 = SiMe3) and Ru(η5-2,3-Me2C5H5)(η5-C5H4R) ( 10, R = tBu; 12, R = SiMe3) are discussed and their use as a MOCVD precursor for the deposition of ruthenium is reported. The molecular structures of 3, 5- 8, 10, and 12 in the solid state are reported. The half-open ruthenocenes 10 and 12, which are liquids at ambient temperature, exhibit significantly shorter Ru-centroid (η5-2,3-Me2C5H5) bond lengths in contrast to ruthenocenes 3 and 5- 8. The thermal behavior of all ruthenocenes was studied by thermogravimetric analysis showing that they evaporate without decomposition at atmospheric pressure. In addition, vapor pressure measurements were carried out to obtain profound information about the volatility of the synthesized sandwich compounds. The highest vapor pressures were found for 10 and 12. It was observed that the higher the number of SiMe3 groups, the higher the deposition temperature. All compounds were applied as precursors in MOCVD. The depositions on Si/SiO2 targets were carried out in a vertical cold-wall CVD reactor between 633 and 688 K with a flow rate of 50 mL min-1 using nitrogen as the carrier gas and oxygen as the coreactant (50 mL min-1). With the tBu-functionalized ruthenocenes 6 and 10 ruthenium thin films were obtained, while mixed ruthenium/SiO2 layers were formed with 2, 7, 8, and 12. The appropriate layers possess thicknesses between 75-135 nm and are conformal and dense as proven by SEM, EDX spectroscopy, and XPS studies. [ABSTRACT FROM AUTHOR]

A series of cobalt half-sandwich complexes of type [Co( η 5 -C 5 H 5 )(L)(L′)] ( 1 : L, L′ = 1,5-hexadiene; 2 : L = P(OEt) 3 , L′ = H 2 C CHSiMe 3 ; 3 : L = L′ = P(OEt) 3 ) has been studied regarding their physical properties such as the vapor pressure, decomposition temperature and applicability within the metal-organic chemical vapor deposition (MOCVD) process, with a focus of the influence of the phosphite ligands. It could be shown that an increasing number of P(OEt) 3 ligands increases the vapor pressure and thermal stability of the respective organometallic compound. Complex 3 appeared to be a promising MOCVD precursor with a high vapor pressure and hence was deposited onto Si/SiO 2 (100 nm) substrates. The resulting reflective layer is closed, dense and homogeneous, with a slightly granulated surface morphology. X-ray photoelectron spectroscopy (XPS) studies demonstrated the formation of metallic cobalt, cobalt phosphate, cobalt oxide and cobalt carbide. [ABSTRACT FROM AUTHOR]