Vladislav V. Krisyuk

CVD of Pure Copper Films from Amidinate Precursor

Copper(I) amidinate [Cu(i-Pr-Me-AMD)]2 was investigated to produce copper films in conventional low pressure chemical vapor deposition (CVD) using hydrogen as reducing gas-reagent. Copper films were deposited on steel, silicon, and SiO2/Si substrates in the temperature range 200–350°C at a total pressure of 1333 Pa. The growth rate on steel follows the surface reaction between atomic hydrogen and the entire precursor molecule up to 240°C. A significant increase of the growth rate at temperatures higher than 300°C was attributed to thermal decomposition of the precursor molecule. It is shown that [Cu(i-Pr-Me-AMD)]2 meets the specifications for the metal organic chemical vapor deposition of Cu-based alloy coatings containing oxophilic elements such as aluminum.

Thermal Behavior of Ti(dpm)2(OiPr)2 Vapors

A study of the thermal behavior of Ti(dpm) 2 (O i Pr) 2 , used as a source compound to obtain TiO 2 films, was carried out. Ti(dpm) 2 (O i Pr) 2 was synthesized by an original technique. Data on vapor pressure and composition, thermal stability, and decomposition products of the compound were obtained, both in vacuo and in the presence of oxygen. A mechanism is suggested for the thermal decomposition of a vapor on a hot surface.

Chemical Vapor Deposition of Iron, Iron Carbides, and Iron Nitride Films from Amidinate Precursors

Iron bis(N,N-diisopropylacetamidinate) [Fe2(µ-iPr-MeAMD)2(2-iPr-MeAMD)2] and iron bis(N,N-di-tert-butylacetamidinate) [Fe(tBu-MeAMD)2] were used as precursors for the metallorganic chemical vapor deposition (MOCVD) of iron-containing compounds including pure iron, iron carbides, Fe3C and Fe4C, and iron nitrides Fe4C. Their decomposition mechanism involves hydrogen migration followed by dissociation of the Fe–N bond and the release of free hydrogenated ligand (HL) and radicals. Surface intermediates are either released or decomposed on the surface providing Fe–N or Fe–C bonds. MOCVD experiments were run at 10 Torr, in the temperature ranges of 350–450°C with Fe2(µ−iPr-MeAMD)2(2-iPr-MeAMD)2 and 280–350°C with Fe(tBu-MeAMD)2. Films prepared from Fe2(µ−iPr-MeAMD)2(2-iPr-MeAMD)2 contain Fe, Fe3C, and Fe4C. Those prepared from Fe(tBu-MeAMD)2 contain Fe, Fe3C, and also Fe4C or Fe4N, depending on the temperature and hydrogen to precursor ratio (H/P) in the input gas. The room-temperature coercive field of films processed from Fe(tBu-MeAMD)2 is 3 times higher than that of the high temperature processed Fe4N films.

Volatile Pd–Pb and Cu–Pb heterometallic complexes: structure, properties, and trans -to- cis isomerization under cocrystallization of Pd and Cu β-diketonates with Pb hexafluoroacetylacetonate

Preparation of volatile heterometallic precursors is a significant step on the way to advanced multicomponent materials. Study of molecular transformations in solution upon precursor synthesis is of importance to optimize the preparation of the stable solid product of desired composition. Two new volatile heterobimetallic complexes, cis-PdL2*Pb(hfa)2 and cis-CuL2*Pb(hfa)2, were obtained (L = 2-methoxy-2,6,6-trimethylheptane-3,5-dionate, hfa = 1,1,1,5,5,5-hexafluoropentane-2,4-dionate) under cocrystallization of trans-bis-beta-diketonates of Pd(II) and Cu(II) with Pb(hfa)2 from organic solvents. Crystals of these compounds are built of discrete bimetallic molecules where transition metal complex isomerized from trans-to-cis form. Complexation followed by isomerization was studied by solution NMR. The bimetallic molecular species were formed early in solution. Enthalpy and activation energy of isomerization were estimated to be 49 and 93 kJ mol−1, respectively. A new synthesis technique of Pd(II) beta-diketonates which is distinguished by simplicity and selectivity as well as the crystal structure of trans-PdL2 is described. Volatility of all obtained compounds was confirmed by thermogravimetric analysis and fractional sublimation in vacuum; Pd-containing heterobimetallic complex appeared to be more volatile than both the initial monometallic complexes and Cu-containing complex.

Iron amidinates as precursors for the MOCVD of iron-containing thin films

Alain N. Gleizes, Vladislav Krisyuk, Lyacine Aloui, Asiya Turgambaeva, Bartosz Sarapata, Nathalie Prud’Homme, Francois Senocq, Diane Samelor, Anna Zielinska-Lipiec, Frederic Dumestre and Constantin Vahlas 1 CIRIMAT, ENSIACET, 118 Route de Narbonne, 31077 Toulouse cedex 4, France. E-mail: constantin.vahlas@ensiacet.fr, phone: +33 562 885 670, fax: +33 562 885 600 2 Nikolaev Institute of Inorganic Chemistry SB RAS ; Ave. Lavrentiev, 3, Novosibirsk, 630090, Russia. E-mail: vladislav.krisyuk@ensiacet.fr 3 AGH University of Science and Technology (AGHUST), Al. Mickiewicza 30, PL-30 059 Krakow, Poland. E-mail : sarapata@agh.edu.pl 4 NanoMePS ; Departement de Genie Physique, INSA, 135 Avenue de Rangueil, 31077 Toulouse Cedex 4, France. E-mail : contact@nanomeps.fr

Mass Spectrometry as a Tool to Study MOCVD Process

Mass spectrometry as a tool study CVD process. Application of two mass spectrometric (MS) techniques to study chemical vapour deposition from organometallic precursors is described. CpCuPEt3 (Cp = η5-C5H5, Et =C2H5) was used as a model precursor in this work.

Isomerization as a tool to design volatile heterometallic complexes with methoxy-substituted β-diketonates

Abstract A series of new heterometallic compounds have been obtained by the co-crystallization of Cu(II) methoxy-substituted β-diketonates and Pb(II) hexafluoroacetylacetonate (hfac) from organic solvents. Their crystal structures were established by X-ray analysis. It is shown that the formation of heterometallic compounds proceeds with geometrical isomerization of the initial copper complexes, which can be controlled by varying terminal substituents in the ligand. Due to the ability of copper complexes to isomerize, the structure of the resulting heterocomplexes can be flexibly and purposefully changed from polymeric to discrete molecular forms. The study of the thermal properties shows that all the reported compounds are volatile and can be re-sublimed in a vacuum, with their composition and structure being retained.

Synthesis, structure, and magnetic properties of the tetranuclear complex [Cu(tmhd)2Pb(hfa)2]2. Influence of temperature-dependent rotation of CF3 groups upon EPR spectra

Abstract A tetranuclear copper–lead complex based on 2,2,6,6-tetramethylheptane-3,5-dionate and 1,1,1,5,5,5-hexafluoropentane-2,4-dionate ligands was prepared. X-ray diffraction study of the crystal structure of the complex was performed at 296, 240, 120, 100, and 85 K. It was shown that the unit cell parameters do not substantially change, but the intramolecular angles and distances significantly changed. A polycrystalline powder of the complex was characterized by continuous wave X- and Q-band electron paramagnetic resonance (EPR) spectroscopy in the 10-350 K temperature range and by magnetic susceptibility based on the Faraday balance technique in the 77-350 K temperature range. The exchange interaction between the two copper ions was not observed which allowed recording the hyperfine interaction (HFI) with one copper nucleus and super HFI with two nonequivalent outer sphere fluorine nuclei. The outer sphere interaction results in the stabilization of the CF3 group. Lowering the temperature resulted in the rotation of the CF3 group and that led to the observation of super HFI from only one fluorine nucleus.

Volatile dimethylgold(III) complex with di-iso-butyldithiophosphinate ligand: synthesis, structure, and thermal behavior in condensed and gas phase

Synthesis and molecular structure of air stable, low-melting dimethylgold(III) complex with dithiophosphinate (CH3)2AuS2PiBu2 (iBu=CH2CH(CH3)2), its thermal properties, and the features as precursor for the metal–organic chemical vapor deposition of gold films are reported. Thermal behavior of the compound in the condensed and gas phase was studied by thermogravimetric analysis and mass spectrometry. Pathways of heterogeneous thermolysis of the compound to elemental gold are discussed. It was found that α-P–H elimination followed by coupling of two alkenyl groups from the coordinated ligand is one of the main thermolysis pathways in condensed and gas phase.