S. V. Sysoev

Investigation of thermal properties of ruthenium(III) Β-diketonate precursors for preparation of RuO2 films by CVD

By means of a tensimetric flow method and a static method with a silica-membrane zero gauge, the dependence of vapour pressure on temperature was obtained for tris(2,4-pentanedionato)ruthenium(III), Ru(aa)3, and tris(1,1,1-trifluoropentane-2,4-dionato)ruthenium(III), Ru(tfa)3. The thermodynamic characteristics of vaporization and sublimation of these complexes were determined. The processes of thermal decomposition of the vapour of the compounds in vacuum, hydrogen and oxygen were investigated by using mass spectrometry in the temperature range 170–550‡C for Ru(aa)3 and 150–620‡C for Ru(tfa)3. The threshold temperatures of the stability of the vapour of the complexes and the rate constants of the thermolysis processes were determined. The main gaseous products of the thermal decomposition and the dependences of their composition on the presence of hydrogen and oxygen were established.

Saturated Vapor Pressure of Iridium(III) Acetylacetonate

The temperature dependency of the saturated vapor pressure of Ir(acac)3 has been measured by the method of calibrated volume (MCV), the Knudsen method, the flow transpiration method, and the membrane method. The thermodynamic parameters of phase transition of a crystal to gas were calculated using each of these methods, and the following values of ΔHT0 (kJ mol−1) and ΔST0 (J mol−1K−1), respectively, were obtained: MCV: 101.59, 156.70; Knudsen: 130.54, 224.40; Flow transpiration: 129.34, 212.23; Membrane: 95.45, 149.44Coprocessing of obtaining data (MCV, flow transportation method and Knudsen method) at temperature ranges 110−200°C as also conducted:ΔHT0 =127.9±2.1 (kJ mol−1 ); ΔST0 =215.2±5.0 (J mol−1 K−1 ).

Study of temperature dependence of saturated vapour pressure of zirconium(IV) β-diketonates

By means of a tensiometric flow method and a static method with a silica-membrane zero gauge, the dependences of saturated vapour pressure on temperature were obtained for the complexes of zirconium(IV) with acetylacetone, trifluoroacetylacetone, hexafluoroacetylacetone, dipivaloylmethane and pivaloyltrifluoroacetone. The thermodynamic characteristics of the evaporation and sublimation of these complexes were determined.

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.

Saturated Vapor Pressure and Crystal Structure of Bis-(2-imino-4-pentanonato)copper(II)

A comprehensive study of copper(II) bis-ketoiminate including tensimetric analysis of sublimation and structure solution has been carried out. The temperature dependence of saturated vapor pressure over Cu(ki)2 crystals derived by the flow method is expressed by the equation lnP(atm)} = 25.31-13750/T, ΔHsubl = -114.2 ± 1.3 kJ· mole-1,Δ Ssubl =210.2 ± 3.0> J· mole-1 · K-1. Crystal data for CuO2N2C10H16: a=15.143(3), b=16.681(8), c=13.795(32) Å, space group Ccca, Z=12, dcalc = 1.47 g/cm3, R=0.029. The structure is molecular and consists of crystallographically independent Cu(ki)2 complexes of two types, one with a cis structure and the other with a cis–trans disordering. The copper atom has a plane square environment of two oxygen and two nitrogen atoms. In the cis isomer, Cu–O 1.938 and Cu–N 1.895 Å; in the disordered complex, all four Cu–O(N) distances are 1.901 Å.

Characterization of some trimethyl(organylamino)silanes—precursors for preparation of silicon carbonitride films

A series of aminosilanes has been synthesized by the reaction of carboxylic acid di(organyl)amides with trimethyliodsilane. A purification method providing an increase in the yield of end products to 82% has been developed. The identity of the products has been confirmed using an elemental analysis and IR, UV, and 1H NMR spectroscopy. The spectral characteristics of the synthesized aminosilanes have been determined. The temperature dependences of the saturated vapor pressure have been established, and the thermodynamic characteristics of the vaporization processes have been calculated. It has been demonstrated that the aminosilanes Me3SiNEt2, Me3SiNHAll, and Me3SiNHPh are heat resistant in the temperature range 296–452 K and have a vapor pressure sufficient for their use in the processes of chemical vapor deposition of a substance, so that they can be recommended as precursors for synthesis of silicon carbonitride films.

Standard enthalpies of formation and metal-ligand bond dissociation enthalpies of some lead(II) β-diketonates

Abstract The standard enthalpies of formation of some lead(II) β-diketonates: Pb(aa) 2 ; Pb(dpm) 2 ; Pb(zis) 2 ; Pb(pta) 2 ; and Pb(hfa) 2 (where aa = pentane-2,4-dionate, dpm = 2,2,6,6-tetramethylheptane-3,5-dionate, zis = 2-methoxy-2,6,6-trimethylheptane-3,5-dionate, pta = 1,1,1-trifluoro-5,5-dimethylhexane-2,4-dionate, and hfa = 1,1,1,6,6,6-hexafluoropentane-2,4-dionate) were determined by solution-reaction calorimetry measurements. The corresponding sublimation enthalpies of the complexes were derived from measurements of saturated vapour pressure by means of the flow method. The homolytic 〈DH R 〉(PbO) and heterolytic 〈DH I 〉(PbO) bond dissociation enthalpies were hence derived.

Properties of aminosilane precursors for the preparation of Si-C-N films

RnSi(NEt2)4 − n aminosilanes have been synthesized by reacting the RnSiCI4 − n (R = H, CH3; n = 1, 2) organylchlorosilanes with diethylamine. Using IR, UV, and NMR (1H, 13C, and 29Si) spectroscopies and elemental analysis, we have identified the reaction products and determined their spectroscopic characteristics. Vapor pressure measurements have been used to determine the saturated vapor pressure as a function of temperature and calculate the thermodynamic characteristics of vaporization. Thermodynamic modeling of chemical vapor deposition processes has been performed with the aim of predicting the phase composition of the deposit as a function of the nature of the precursor and process conditions.

Films based on the phases in the Si-C-N System: Part 1. Synthesis and characterization of bis(trimethylsilyl)ethylamine as a precursor

The characterization of bis(trimethylsilyl)ethylamine was carried out using a combination of IR, UV, 1H, 13C, 29Si, and 15N NMR spectroscopy, as well as elemental analysis. The spectral characteristics of the compound were determined. The temperature dependence of the saturated vapor pressure was established by tensimetric studies, and the thermodynamic characteristics of vaporization were calculated. Thermodynamic simulation of the chemical vapor deposition was performed and was used as a basis for predicting the composition of the deposited phase complexes depending on the type of reagent and the process conditions.

Thermal Properties of Some Volatile Titanium (IV) Precursors

The tensimetric study was carried out for TTIP, Ti[OEt]4 and Ti[DMAP]4 by means of static method with a quartz membrane zero-manometer and flow method using He as gas-carrier (the compounds were assumed to vaporize in a monomolecular form) in a wide range of temperatures. Temperature dependencies of saturated vapor pressure were measured; the evaporation thermodynamic parameters have been calculated (Table 1). Data obtained for TTIP can be compared with values calculated from literature data [1, 2].