METHOD FOR THE DEPOSITION OF NICKEL AND/OR NICKEL OXIDE FROM THE GAS PHASE, AND NOVEL NICKEL COMPOUNDS HAVING STABLE VAPORISATION CHARACTERISTICS

Abstract: A method is described for the deposition of nickel oxide and/or nickel from the gas phase, wherein an Ni( beta -diketonate)2.Lm is used as the nickel compound to be vaporised, where L is an organic (poly)ether and/or (poly)amine and m is 1 or 2 and indicates the number of ligands L bonded to one nickel ion. Novel nickel compounds of the type Ni(R<1>R<2>R<3>C-CO-CR<4>-CO-R<5>R<6>R<7>)2.-R<8>-A<1>-(CH2CH2-A<2>)n-R<9>, where R<1> and R<7> independently of one another represent H, CH3 or CpF2p+1, where p is a number from 0 to 3, and R<2>, R<3>, R<4>, R<5> and R<6> independently of one another represent H, CH3, F or CF3; A<1> and A<2> independently of one another represent O or NR<10>; R<8>, R<9> and R<10> each represent a hydrogen atom or a C1-C3 alkyl group, and in particular a methyl group, whereby R<8> and R<9> may also be joined to from a C2-C3 alkylene group, and n is a number from 1 to 3; with the proviso that when A<1> and A<2> represent NR<10>, n is 2, are also described.

Description: Method for the deposition of nickel and/or nickel oxide from the gas phase, and novel nickel compounds having stable vaporisation characteristics The invention relates to a method for the deposition of nickel and/or nickel oxide on a substrate by vaporisation of a nickel compound from the liquid phase or solid phase, followed by decomposition in the gas phase and deposition from the gas phase on the substrate, or adsorption from the gas phase on the substrate followed by decomposition. A method of this type requires the use of volatile nickel compounds which display stable vaporisation characteristics from the solid phase, but even better from the liquid phase. Methods of this type include, for example, but are not restricted to, chemical vapour deposition (CVD) processes. CVD is known in a large number of variants, of which metal-organic MO-CVD, also known as organometallic (OM) CVD, is mentioned as a first example. In this variant volatile compounds of a metal atom (formally uncharged) or metal ion (formally charged, such as the divalent positively charged nickel ion), wherein the metal is bonded via carbon, oxygen, nitrogen or other atoms to an organic group, are used. Said organic group can, in the case under consideration; be electrically neutral or negatively charged, to compensate for a positive charge on the metal. In addition to CVD, the term Vapour Phase Epitaxy VPE is also used for specific embodiments. Moreover, it is also possible to impregnate porous substrates, via the vapour phase and decomposition of nickel compounds, with nickel oxide and/or nickel via CVI; Chemical Vapour Infiltration. Nickel or nickel oxide are currently produced on a large industrial scale by decomposition of nickel tetracarbonyl Ni(CO) 4 in or from the gas phase. The use of Ni(CO) 4 for CVD applications has already been described in US Patent 2,759,848 in 1956 by M. V. Sullivan for Bell Telephone Laboratories. Nickel tetracarbonyl is used on a large industrial scale for the preparation of nickel, inter alia by the largest nickel producer in the world; INCO (International Nickel Company, for example in Canada and the United Kingdom). However, this compound is extremely toxic and any contact with man is harmful, immediately or later. For these reasons, industrial processes using Ni(CO) can be carried out only in completely automated processes, where human presence in the vicinity of this toxin is avoided. It is predictable that in the course of time restrictions will be placed even on this use of Ni(CO) 4 and that the need for volatile and stable, less toxic substitutes for a number of processes will become greater. Other nickel compounds have also been used for this purpose. For instance, G. T. Staut, D. C. Driscoll, P. A. Dowben, S. Banfuss and M. Grada describe the use of bis(cyclopentadienyl)nickel in Thin Solid Films 153 (1987) p.421. However, this compound does not have the stability with respect to atmospheric oxygen and water vapour which is needed for an efficient CVD process. Some researchers have also tried to use nickel bis(β-diketonates) without neutral ligands, such as K. Sugimoto, M. Seto, S. Tanaka and N. Hara, Journal of the Electrochemical Society 140 (1993) p. 1586 with Ni(acac) 2 , or using water as neutral ligand, such as H. L. van Hemert, L. B. Spendlove and R. E. Sievers in the same journal, 112 (1965) pp. 1123-1126 with [acac = acetylacetonate; Mac = hexafluoroacetylacetonate]. As is described in Example 2 below with Ni(hfac) 2 .3H 2 θ, these nickel complexes with water have disadvantages: it is not easy to keep the amount of water in the complex stable and consequently the volatility is not stable. Moreover, during and after vaporisation at elevated temperature, water gives rise to hydrolysis of the nickel complex and, consequently, to de¬ composition, that is to say non-constant vaporisation characteristics. A group of nickel compounds have now been found which meet the specified requirements of good volatility and stability during vaporisation. According to the invention use is made of metal-organic nickel compounds of type 1: Ni 2+ (β-diketonate) 2 .l-- m , wherein β-diketonate = the anion obtained by removing a hydrogen ion IT 1" from acetylacetone or 2,4-pentanedione, which has the symbol Hacac, a negatively charged acac " group remaining, or of a compound derived from acetylacetone by substitution of hydrogen atoms H 1 and/or H 2 by organic groups or fluorine atoms; L = a neutral organic molecule which acts as a ligand for the nickel ion and contains oxygen atoms in the form of an ether -O-, but preferably nitrogen atoms in the form of an amine -N<; m = integer or fraction which indicates the number of molecules L bonded per Ni ion. In the compounds according to the invention, in general m is one, for the reasons to be given below. The abbreviations used here have the following meaning: acac = acetylacetonate, derived from Hacac: acetylacetone (2,4-peπtanedione); hfac = hexafluoroacetylacetonate, derived from Hhfac = hexafluoroacetyl- acetone = l,l,l,5,5,5-hexafluoro-2,4-pentanedione; tfac = trifluoroacetylacetonate, derived from Htfac = trifluoroacetylacetone - l,l,l-trifluoro-2,4-pentanedione; TMEDA = N, N, N', N'-tetramethylethylenediamine; PMDETA = N, N, N', N", N"-pentamethyldiethylenetriamine; HMTETA = N, N, N', N", N", N^-hexamethyltriethylenetetramine; DME = dimethoxy ethane; diglyme = diethylene glycol dimethyl ether. A few compounds of type 1 have already been known per se for some con¬ siderable time, such as those described by Y. Saito, T. Takeushi and Y. Fukuda in Bull. Chem. Soc. Japan, 54 (1981), p. 196. It has also been suggested that representatives of this group have a certain volatility. However, up to now it has always been found and/or assumed that the neutral molecules L, including those containing oxygen or nitrogen in the indicated form, were so loosely bonded that on vaporisation by heating, said ligands L were partially or completely lost from the nickel-containing molecule as a result of dissociation. The decomposition behaviour during vaporisation by heating gives rise to significant practical problems for deposition of nickel on substrates via the said gas phase processes. After all, the industry desires a constant rate of vaporisation for a metal compound in order, thus, to be able to use a complete stock of metal-organic starting material for uniform covering under conditions which as far as possible are kept constant. Now, this is not possible with a starting material which decomposes during vaporisation, because the vaporisation characteristics of the decomposition product will differ from those of the starting material. In general, it is found that the decomposition product, for example Ni(acac) 2 from Ni(acac) 2 .L has poorer vaporisation performance than the starting material. This behaviour on decomposition stands in the way of industrial application of MO-CVD for these cases. A second, important reason for seeking novel volatile metal-organic nickel starting materials ("precursors") is the fact that some known compounds used according to the invention, although they are stable on vaporisation, still occur as a solid at the vaporisation temperature. In CVD and related technologies it is known that constant and rapid vaporisation of solids is technologically more difficult to achieve and, consequently, is more expensive than that of liquids. Differences in crystal size and shapes of solids are also an obstacle to constant and controllable vaporisation. The invention is based on the discovery of compounds which combine a surprisingly good stability with a high volatility at elevated temperature. In addition, compounds are preferably used which have a low melting point, so that they are already liquid at the vaporisation temperature. An example of behaviour of this type is given by the following compounds: Ni(hfac) 2 .TMEDA (compound la) gives stable vaporisation characteristics but has a melting point of 127-128 °C, which is dependent on the purity of the preparation. A good rate of vaporisation can be achieved at about 100°C, from the solid. Ni(hfac)2.PMDETA (compound lh) has the same advantages as Ni compound la, but in addition melts only a few degrees above room temperature (33-35°C) and is therefore a liquid at 100°C, which offers additional advantages. These substances decompose from the vapour phase by thermal decomposition at a temperature appreciably higher than the vaporisation temperature and have been found to have unrestricted stability. During this decomposition, under oxidising conditions, nickel oxide is deposited and under reducing conditions, during or after the decomposition, nickel is deposited. Oxidising conditions can arise under diverse conditions, but the simplest form thereof is the addition of gaseous oxygen to the gas mixture before or during the decomposition. Reducing conditions can be generated in many corresponding ways, according to the invention or according to the literature, for example by adding gaseous hydrogen to the gas phase before, during or after the decomposition process. Nickel compounds which can be used according to the invention are, for example, complexes of Ni 2+ with the following groups of charged and neutral ligands: a) Negatively charged β-diketonate ligands: Those which comply with formula 2: [ R 1 R 2 R 3 C-CO-CR 4 -CO-R 5 R 6 R 7 ] " 2 wherein R 1 and R 7 independently of one another represent H, CH 3 , or C F_ +1 , where p is a number from 0 to 3, and R 2 , R 3 , R 4 , R 5 and R 6 independently of one another represent H, CH 3 , F or CF 3 . It was found that the stabilising effect of the neutral ligand L and the volatility of the Ni complex increased with an increasing number of fluorine atoms in the β-diketonate, so that in formula 2 the group R 1 R 2 R 3 C preferably represents a C j -C 8 perfluoroalkyl group. The following derivatives of 2,4-pentanedionates have, for example, proved suitable as β-diketonate ligands in effective nickel complexes: 2,4-pentanedionate (acac); trifluoropentanedionate (tfac); hexafluoropentanedionate (hfac); 1,1,1,2,2,3,3- heptafluoro-7,7-dimethyl-4,6-octanedionate (hfod); and 2,2,6,6-tetramethyl-3,5- heptanedionate (tmhd), which is also known as dipivaloylmethanate (dpm). b) Neutral ligands L: These are compounds which have at least one oxygen or nitrogen atom, such as diethyl ether, trimethylamine or pyridine, or which have more than one oxygen and/or nitrogen atom, each of which is bonded via two carbon atoms. Examples of the latter group are bipyridyl and 1,10-phenanthroline, but also nitrogen-containing rings which carry an aminomethyl or alkoxymethyl group in the α-position, such as 2-dimethylaminopyridine or 2-(methoxymethyl)piperidine. However, the preference is for compounds which comply with formula 2: R 8 -A 1 -(CH 2 -CH 2 -A 2 ) n -R 9 2 wherein A 1 and A 2 independently of one another represent O or NR 10 , R 8 , R 9 , and R 10 each represent a hydrogen atom or a C j -C- alkyl group and in particular a methyl group, whereby R 8 and R 9 may also be joined to form a C^-C^ alkylene group, and n is a number from 0 to 4, in particular 1-3. Preferably, in formula 2 A 2 and, optionally, A 1 represent N-CH 3 , and R 8 and R 9 represent CH 3 . When two charged Mac ligands are used on Ni, stabilising effects are found and a higher volatility of the Ni(hfac)- > group on the addition of polyethylene ethers of the type CH 3 O(CH 2 CH 2 O) n CH 3 , such as dimethoxyethane DME (n = 1) and diglyme (n = 2), or the type (CH 2 CH 2 O) n+1 , such as dioxane, trioxonane and tetraoxacyclo- dodecane. However, the effects are even greater with the corresponding permethylated polyethyleneamines for example where n = 1 (TMEDA) or 2 (PMDETA), or [CH 2 CH 2 N(CH 3 )] n+1 , such as trimethyltriazonane (n = 2). As has been described, a low melting point is obtained for the nitrogen compound where n = 2 (compound lb), which makes the compound particularly suitable for the purpose of the invention. As the said nitrogen ligands L where n = 1 or 2 are commercially available, these are currently preferred, especially those where n = 2. The oxygen-containing ligands mentioned show the stabilisation effect to a lesser extent than the corresponding nitrogen compound (having the same value for n). On the other hand, the oxygen-containing ligands lead to an increased volatility. Because of their lower price it can also be advantageous for a number of applications to use these nickel complexes, for example Niφfac^.diglyme or Ni(tfac)- > .diglyιne. Furthermore, for these polyethers, the compounds having a higher n value (3 or above) are more readily obtainable, and at a lower price, than are the corresponding permethylated polyethyleneamines. Ether-amines, such as the partially or completely alkylated derivatives of ethanolamine, diethanolamine, oxybisethylamine, aminoethylaminoethanol, aminoethoxyethanol and oxadiazonane, can also be used according to the invention. According to the invention, use can also be made of solutions of the said nickel complexes, for example NiQifac^.TMEDA, in an organic solvent, which, depending on the requirement, either has a low boiling point and also vaporises during the vaporisation process or has a high boiling point and does not vaporise as well. Examples of the first type of solvent are monohydric ethers, amines and diethers, such as DME. Using these solvents an oxygen-containing and therefore oxidising, atmosphere can also be created during decomposition of the Ni starting material in the gas phase. Conversely, for example, a polyether which has a high molecular weight (high value for n) will act as a solvent for better stabilisation and vaporisation, but will itself not also vaporise. In order to explain the good stabilising effect of compounds according to the invention which have an increased volatility it is assumed that the neutral ligands L fill unoccupied coordination sites on the nickel ion which otherwise would be filled either by random impurities (such as water) or by auto-reaction with other nickel-containing molecules and would influence the stability and volatility in an uncontrollable or undesirable manner. According to this interpretation, the complexes mentioned here show a nickel coordination which is saturated as well as possible, it being assumed in the literature that the highest coordination number of nickel is six (four oxygen sites of the β-diketonate and two other sites for the ligand L). As a consequence of this stabilisation, it has been found that, in particular, compounds la and lb withstand the effects of air or water (vapour) for a prolonged period. This makes them outstandingly suitable for the purpose of the invention. The method for the deposition of nickel and/or nickel oxide using the starting materials described above is carried out by vaporisation at a controllable and, in so far as is desirable, a constant rate of vaporisation from the solid or liquid phase of the described nickel compounds of general formula Ni(β-diketonate) 2 .L m , followed by thermal or other decomposition in the gas phase of said compoimds at a fixed elevated temperature or in a desired temperature range, as a consequence of an increased volatility with respect to the corresponding compounds Ni(β-diketonate) 2 , under oxidising conditions during and after the deposition for the formation of nickel oxide or under reducing conditions during and/or after the deposition for the formation of nickel or for a mixture of nickel and nickel oxide. The conditions for a method of this type are known to those skilled in the art. If desired, the deposition according to the invention can also be carried out using another metal in addition to nickel, for example zirconium and/or yttrium. For metals of this type, use can then be made of a complex of the metal with a diketonate ligand and/or a neutral ligand L, as described above. The invention also relates to novel nickel complexes which can be used in the method for the chemical vapour deposition of nickel and/or nickel oxide, as described above. The novel compounds have the general formula 4: Ni(R 1 R 2 R 3 C-CO-CR 4 -CO-R 5 R 6 R 7 ) 2 .R 8 -A 1 -(CH 2 -CH 2 -A 2 ) n -R 9 ___ wherein R 1 and R 7 independently of one another represent H, CH 3 or C F^ j , where p is a number from 0 to 3 and R 2 , R 3 , R 4 , R 5 and R 6 independently of one another represent H, CH 3 , F or CF 3 ; A 1 and A 2 independently of one another represent O or NR 10 ; R 8 , R 9 and R 10 each represent a hydrogen atom or a C j -C j alkyl group, and in particular a methyl group, whereby R 8 and R 9 may also be joined to form a C- j -C- alkylene group, and n is a number from 1 to 3; with the proviso that if A 1 and A 2 represent NR 10 and R 8 represents C j -C^ alkyl, n is 2. The novel nickel compounds for which, in formula 4, the group R 1 R 2 R 3 C represents a C j -C^ perfluoroalkyl group and n is 2 are particularly preferred. An example of a novel nickel compound is Ni(hfac) 2 .PMDETA. The nickel compounds as described above are likewise suitable for use in spray pyrolysis, dip coating and sol-gel deposition, for example in the field of microelectronics. EXAMPLE 1 Preparation of nickel compounds la to le The following methods, which are not restrictive for the preparation conditions to be chosen, are given as an example of the preparation of nickel compounds used. la was prepared from TMEDA (11.12 g = 95.88 mmol), which was added to a stirred suspension of Ni(hfac) 2 .3H 2 O (25.25 g = 47.94 mmol) in toluene (250 ml). The residual dark green, turbid solution was stirred for 0.5 hour in the presence of dry magnesium sulphate and then filtered and evaporated to dryness. The residue was dis- solved in toluene (75 ml) and this solution was again evaporated to dryness. A green crystalline product la (27.42 g = 97.2%) having a melting point of 127-128°C was obtained from this. Elemental analysis for C 16 H 18 N 2 O 4 F 12 Ni: found (calculated) after sublimation: C 32.66 (32.61) 32.67; H 3.18 (3.06) 3.18; N 4.76 (4.76) 4.71 %. 1H NMR spectroscopy δ(CH) 8.22 (singlet); δ(CH 2 N) 48 and 93 (broad); δ(CH 3 N) 85 and 109 (broad). 19 F NMR: δ(CE 3 ) 139.2 and 141 (singlets). Chemical shifts δ were measured on a Varian Unity 400 machine, in ppm, in the solvent C 6 D 6 , using tetramethylsilane TMS ( X H) as reference, or external CFC1 3 in acetone ( 19 F). la can be sublimed at 60°C/0.05 mm Hg, which is a rough indication of the volatility at low temperature. The sublimate gave a correct elemental analysis (margin of error determination < 0.2 %). lb was prepared analogously from 1.05 g = 2.0 mmol of Ni(hfac) 2 .3H 2 O and 0.35 g = 2.0 mmol PMDETA in 1.21 g yield = 93.8 %; green coloured, with melting point of 33-35°C. Elemental analysis for C^H^ j O^^Ni: successively found (calculated) and after sublimation: C35.43 (35.31) 35.33; H 4.00 (3.87) 3.84; N 6.49 (6.51) 6.63 %. lb sublimes at 70°C/0.03 mm Hg. Ni hfac^.DME (le) was prepared correspondingly from 1.05 g = 2.0 mmol of Ni(hfac) 2 .3H 2 O and 0.72 g = 8.0 mmol of DME in 1.05 g yield = 93.3%; green- coloured solid having a melting point of 55-56°C. Elemental analysis for C 14 H 12 O 6 F 12 Ni: found (calculated) after sublimation: C 29.82 (29.86) 29.64; H 2-26 (2.13) 2.16%. lc sublimes at 50°C/0.01 mm Hg. Ni(hfac) 2 .diglyme (Id) was prepared correspondingly from 1.05 g = 2.0 mmol of Ni(hfac) 2 .3H 2 O and 0.27 g = 2.0 mmol of diglyme in 1.05 g yield = 86.8% in the form of a green-coloured syrupy liquid. Elemental analysis for C 16 H 16 O 7 F 12 Ni: found (calculated): C 31.66 (31.65); H 2.81 (2.64) %. Ni(hfac) 2 .diglyme.H 2 O (le) was obtained by allowing Id to stand in air. After recrystallisation from pentane, le was isolated in 56.1% yield; green-coloured, with a melting point of 75-77°C. Elemental analysis for C 16 H 18 O 8 F 12 Ni: found (calculated) after sublimation: C 30.53 (30.73) 30.66; H 3.15 (2.88) 3.31 %. le sublimes at 75°C/0.03 mm Hg. The preparation and the use of le showed that the diglyme compound Id is hygroscopic and slowly converts to le on exposure to air. Both compounds are volatile and as such can be used for the purpose of the invention. However, a mixture of Id and le which is obtained when Id comes into contact with water (vapour) does not have a constant volatility. EXAMPLE 2 Nickel oxide depositions The following experiments, the conditions of which are not limiting for depositions with the compounds used, are described as an example of depositions of NiO using the novel starting materials. These experiments were carried out in a hot-wall reactor with vertical through- flow. In this reactor the growth kinetics were determined as a function of the reactor temperature. The Ni depositions were carried out in a mixed gas composed of N 2 and O 2 (1:1) under a reactor pressure of 10 mm Hg; under these conditions yellow/green nickel oxide was formed. For comparison, depositions were also carried out using the prepared and purified, but also commercially available compound Ni(hfac) 2 .2H 2 O If. With this compound it was not possible to measure precise deposition rates after vaporisation and decomposition in or from the gas phase at various temperatures because compound If decomposes in the gas phase, releasing water, which leads to compounds Ni hfac)^- (2-x)H 2 O (0 ≤ x ≤ 2) which have differing volatilities and decomposition behaviour. Attempts to remove all of the water beforehand were unsuccessful. However, these problems do not arise if one of the compounds according to the invention, such as la-d, is used. In Figure 1 the deposition rates are shown as a function of the reciprocal evaporation temperature for the individual complexes Ni hfac^.TMEDA lb and Ni(hfac) 2 .2H 2 O If at a substrate temperature of 800 ± 5°C. EXAMPLE 3 Mixed depositions of metal oxides Here examples are described which are characteristic of the numerous mixing possibilities which exist as a result of mixing volatile metal compounds which vaporise and decompose simultaneously with a nickel "precursor" and thus produce deposits of mixed metal oxides, which may or may not be in a single crystal phase or amorphous phase. Specifically, it is possible to co-deposit other metal oxides at the same time by simultaneous vaporisation and decomposition of other metal starting materials, for example by MO-CVD. This has been demonstrated by depositing zirconium oxide and/or yttrium oxide by vaporisation and decomposition at comparable temperatures as the nickel compound of, respectively, Zr(tfac) 4 or Zr[N(C 2 H 5 ) 2 ] 4 and Y(tmhd) 3 , by means of which, for example, zirconium oxide can be formed, on its own or mixed with yttrium oxide (in a single crystal phase). In this way, using the MO-CVD method described, porous anodes having a layer thickness of, for example, 10 μm, deposited within a relatively short time, have been made for SOFC (solid oxide fuel cells), which anodes, according to electrochemical measurements at 1000°C (the operating temperature of current SOFCs) give a good anode performance when supplied with hydrogen in a semiconductor cell, using solid YSZ as substrate and electrolyte. The depositions were carried out in a vertical hot-wall reactor with stagnating flow, in which particles were precipitated by means of particle-precipitated (PP-)MO- CVD. This reactor was heated by a three-zone furnace. Said reactor contained a substrate, which was positioned on a substrate table (diameter 100 mm), which could be cooled by water or gas. The starting materials were injected through a large injection nozzle (diameter 100 mm), which had a length of 11.5 cm. With PP-MO-CVD, these dimensions give a virtually homogeneous deposition on a 56 x 56 mm 2 substrate. The substrate used was polycrystalline zirconium oxide ZrO 2 which had been stabilised with 8% by volume yttrium oxide Y 2 O 3 (YSZ = yttria-stabilised zirconia). By varying the mixing ratio of the various "precursors", it is possible to select the deposited ratio between the oxides of Zr Y/Ni, and thus, in general, the mixing ratio of metal oxides as required. In these experiments, nickel contents of from less than 30% to more than 50% were chosen for these Ni- or NiO-YSZ mixtures. The structure of the layer (dense or porous) is influenced by the choice of furnace temperature. This depends on the reactor configuration. Thus, open structures are found on deposition at 850°C and dense structures are found at higher temperatures, for example 950°C. By cooling the substrate, the deposition rate can be increased by means of the so-called theπnophoretic effect. EXAMPLE 4 Nickel depositions The following experiments are described as an example of the deposition of Ni using the novel starting materials. These experiments were carried out in a vertical stagnating cold-wall reactor. Porous substrates were positioned in said reactor and provided with a nickel coating via CVI (chemical vapour infiltration). The starting compound used was Ni hfae^.PMDETA lb which was vaporised at 100°C. The substrate table was held at 400 or 500°C, the precursors decomposing. The reaction took place in an N 2 -H 2 stream (1:1) and under a reactor pressure of 0.5 mm Hg. In all cases Ni° was deposited, which was dis¬ seminated homogeneously through the porous support. The porous support used was polycrystalline zirconium oxide ZrO 2 , which had been stabilised with 8% by volume yttrium oxide Y 2 O 3 .

Claims: CLAIMS 1. Method for the deposition of nickel oxide and/or nickel by vaporisation, from the solid or liquid phase, of a nickel compound, followed by decomposition, in the gas phase, of said compound, under oxidising conditions during and after the deposition for the formation of nickel oxide or under reducing conditions during and/or after the deposition for the formation of nickel or of a mixture of mckel and nickel oxide, characterised in that a compound of general formula 1: Ni(β-diketonate) 2 .L ta 1 wherein, L is an organic (poly)ether and/or (poly)amine and m is 1 or 2 and indicates the number of ligands L which are bonded to one nickel ion, is used as nickel compound to be vaporised. 2. Method according to Claim 1, characterised in that in the nickel compound the β-diketonate has formula 2; [ R 1 R 2 R 3 C-CO-CR 4 -CO-R 5 R 6 R 7 ] " 2 wherein R 1 and R 7 independently of one another represent H, CH 3 , or C F^, +1 , where p is a number from 0 to 3, and R 2 , R 3 , R 4 , R 5 and R 6 independently of one another represent H, CH 3 , F or CF 3 . 3. Method according to Claim 2, characterised in that in formula 2 R R 2 R 3 C represents a CJ-CJ perfluoroalkyl group. 4. Method according to Claim 2 or 3, characterised in that the β-diketonate is l,l,l-trifluoro-2,4-pentanedionate (tfac), l,l,l,5,5,5-hexafluoro-2,4-pentanedionate (hfac), l,l,l,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionate (hfod), 2,2,6,6- tetramethyl-3,5-heptanedionate (tmhd) or 2,4-pentanedionate (acac). 5. Method according to any one of Claims 1-4, characterised in that the ligand L has the formula 2: R 8 -A 1 -(CH 2 -CH 2 -A 2 ) n -R 9 2 wherein A 1 and A 2 independently of one another represent O or NR 10 , R 8 , R 9 and R 10 each represent a hydrogen atom or a C 1 -C 3 alkyl group and in particular a methyl group, whereby R 8 and R 9 may also be joined to form a C- j -C j alkylene group, and n is a number from 1 to 3 and m is the number 1. 6. Method according to Claim 5, characterised in that, in formula 2, A 1 and A 2 represent N-CH 3 and R 8 and R 9 represent CH 3 . 7. Method according to Claim 5 or 6, characterised in that in formula 2 n is 2. 8. Method according to Claim 7, characterised in that the nickel compound is nickel bis(hexafluoropentanedionate)-pentamethyldiethylenetriamine. 9. Method according to any one of Claims 1-8, characterised in that one or more other metals, or metal oxides, are also deposited. 10. Method according to any one of Claims 1-9, characterised in that the nickel compound is formed during the process by adding the ligand L in the liquid or vapour phase to the nickel bisdiketonate. 11. Nickel compound of general formula 4: Ni(R 1 R 2 R 3 C-CO-CR 4 -CO-R 5 R 6 R 7 ) 2 .R 8 -A 1 -(CH 2 -CH 2 -A 2 ) n -R 9 4 wherein R 1 and R 7 independently of one another represent H, CH 3 or C F 2p+1 , where p is a number from 0 to 3 and R 2 , R 3 , R 4 , R 5 and R 6 independently of one another represent H, CH 3 , F or CF 3 ; A 1 and A 2 independently of one another represent O or NR 10 ; R 8 , R 9 and R 10 each represent a hydrogen atom or a C j -C j alkyl group, and in particular a methyl group, whereby R 8 and R 9 may also be joined to form a C^-C^ alkylene group, and n is a number from 1 to 3; with the proviso that if A 1 and A 2 represent NR 10 and R 8 represents C j -C^ alkyl, n is 2. 12. Nickel compound according to Claim 11, characterised in that in formula 4 R 1 R 2 R 3 C represents a C^ ^ perfluoroalkyl group and n is 2.

Inventors: MACKOR ADRIANUS, SPEE CAROLUS IDA MARIA ANTONIU, TIMMER KLAAS, MACKOR, ADRIANUS, SPEE, CAROLUS, IDA, MARIA, ANTONIUS, TIMMER, KLAAS
Applicants: MACKOR ADRIANUS, SPEE CAROLUS IDA MARIA ANTONIU, TIMMER KLAAS, TNO, MACKOR, ADRIANUS, NEDERLANDSE ORGANISATIE VOOR TOEGEPASTNATUURWETENS, SPEE, CAROLUS, IDA, MARIA, ANTONIUS, TIMMER, KLAAS
Application year: 1995
Main classification: C07F15
IPC codes: C07F15, C23C16