Synthesis and characterization of (β-diketonato) silver vinyltriethylsilane compounds and their application to CVD of silver thin films. Crystal structure of the (2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionato)silver vinyltriethylsilane dimer

Article abstract of DOI:10.1021/om960013e

New silver complexes of alkenes of empirical formula (β-diketonato)Ag(VTES), where β-diketonato = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionato (hfac) (1), 1,1,1-trifluoro-2,4-pentanedionato (tfac) (2), and 2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionato (fod) (3) and VTES = vinyltriethylsilane, were prepared from reactions of Ag₂O with β-diketones in the presence of VTES. All compounds were characterized by elemental analyses and ¹H, ¹³C, and ¹⁹F NMR and IR spectra. The crystal structure of compound 3 determined by X-ray diffraction analysis showed a dimeric silver species with coordination of the C=C double bond of VTES, two oxygen atoms of a chelating fod ligand, and the methine C atom of another fod in the solid state. Hot-wall chemical vapor deposition experiments revealed that compound 1 is suitable as a precursor to deposit pure silver films in the temperature range 160-280°C.

Full text of DOI:10.1021/om960013e

Organometallics 1996, 15, 2575-2578
2575
Syn th esis a n d Ch a r a cter iza tion of (â-Dik eton a to)silver
Vin yltr ieth ylsila n e Com p ou n d s a n d Th eir Ap p lica tion to
CVD of Silver Th in F ilm s. Cr ysta l Str u ctu r e of th e
(2,2-Dim eth yl-6,6,7,7,8,8,8-h ep ta flu or o-3,5-octa n ed ion a to)silver
Vin yltr ieth ylsila n e Dim er
Kai-Ming Chi* and Kuo-Hsien Chen
Department of Chemistry, National Chung Cheng University,
Ming-Hsiung, Chia-Yi, Taiwan 621, ROC
Shie-Ming Peng* and Gene-Hsiang Lee
Department of Chemistry, National Taiwan University, Taipei, Taiwan, ROC
Received J anuary 9, 1996X
Summary: New silver complexes of alkenes of empirical
formula (â-diketonato)Ag(VTES), where â-diketonato )
1,1,1,5,5,5-hexafluoro-2,4-pentanedionato (hfac) (1), 1,1,1-
trifluoro-2,4-pentanedionato (tfac) (2), and 2,2-dimethyl-
6,6,7,7,8,8,8-heptafluoro-3,5-octanedionato (fod) (3) and
VTES ) vinyltriethylsilane, were prepared from reac-
tions of Ag2O with â-diketones in the presence of VTES.
All compounds were characterized by elemental analyses
thermal or plasma conditions. In contrast to (â-dike-
tonato)Cu(alkene) compounds being widely used as CVD
precursors,8 no silver analogue was reported to be
suitable for CVD although such complexes have been
known for years.9,10 It is probably due to loss of alkene
during or before these complexes are vaporized. In this
paper, we report the synthesis and characterization of
(â-diketonato)Ag(VTES) complexes, in which VTES )
vinyltriethylsilane and â-diketonato ) 1,1,1,5,5,5-
hexafluoro-2,4-pentanedionato (hfac) (1), 1,1,1-trifluoro-
2,4-pentanedionato (tfac) (2), and 2,2-dimethyl-
6,6,7,7,8,8,8-heptafluoro-3,5-octanedionato (fod) (3), a
unique single-crystal structure of compound 3, and the
results of hot-wall CVD experiments with compound 1
as a precursor.
1
and H, 13C, and 19F NMR and IR spectra. The crystal
structure of compound 3 determined by X-ray diffraction
analysis showed a dimeric silver species with coordina-
tion of the CdC double bond of VTES, two oxygen atoms
of a chelating fod ligand, and the methine C atom of
another fod in the solid state. Hot-wall chemical vapor
deposition experiments revealed that compound 1 is
suitable as a precursor to deposit pure silver films in
the temperature range 160-280 °C.
Resu lts a n d Discu ssion
In tr od u ction
Syn th esis of (â-diketon ato)Ag(VTES) Com plexes.
The title compounds were prepared from reactions of
Ag2O with the corresponding â-diketones in the pres-
ence of vinyltriethylsilane according to eq 1. The
Metal-organic chemical vapor deposition (MOCVD) of
metals attracts great research interest as the result of
the important applications in the microelectronics in-
dustry.1 For instance, CVD of aluminum and tungsten
thin films can be used to deposit interconnected layers
in microelectronic devices. Development of CVD of
highly conductive coinage metals recently became cru-
cial because of the reduction in dimensions of new
generation microelectronic devices. Several organome-
tallic compounds2-7 including [AgC(CF3)dCF(CF3)]4,
[Ag(O2CCF3)]n, (â-diketonato)Ag(PR3), and (hfac)Ag-
(CtNMe) were used to deposit silver films under
Ag2O + 2â-diketone + 2VTES f
2(â-diketonato)Ag(VTES) + H2O (1)
reactions were carried out in Et2O solutions at room
temperature, and products were isolated on extraction
with hexane and removal of volatile species in vacuo.
Similar methods were used to prepare other (â-diketo-
nato)Ag complexes.5,10-13 Compounds 1 and 2 are
* To whom correspondence should be addressed.
X Abstract published in Advance ACS Abstracts, May 1, 1996.
(1) (a) Sherman, A. Chemical Vapor Deposition for Microelectronics:
Principles, Technology, and Applications; Noyes Publications: Park
Ridge, NJ , 1987. (b) Hess, D. W.; J ensen, K. F. Microelectronics
Processing, Chemical Engineering Aspects; American Chemical Soci-
ety: Washington, DC, 1989.
(2) Oehr, C.; Suhr, H. Appl. Phys. A 1989, 49, 691.
(3) (a) Shapiro, M. J .; Lackey, W. J .; Hanigofsky, J . A.; Hill, D. N.;
Carter, W. B.; Barefield, E. K. J . Alloys Comp. 1992, 187, 331. (b)
Baum, T. H.; Larson, C. E. U.S. Patent 5,096,737, Mar 1992.
(4) J effries, P. M.; Wilson, S. R.; Girolami, G. S. J . Organomet. Chem.
1993, 449, 203.
(8) (a) Reynolds, S. K.; Smart, C. J .; Baran, E. F.; Baum, T. H.;
Larson, C. E.; Brock, P. J . Appl. Phys. Lett. 1991, 59, 2332. (b) J ain,
A.; Chi, K.-M.; Hampden-Smith, M. J .; Kodas, T. T.; Paffett, M.; Farr,
J . D. J . Mater. Res. 1992, 7, 261. (c) Norman, J . A. T.; Muratore, B.
A.; Dyer, P. N.; Robert, D. A.; Hochberg, A. K. J . Phys. (Paris) 1991,
IV, C2/271. (d) J ain, A.; Chi, K.-M.; Hampden-Smith, M. J .; Kodas,
T. T. J . Electrochem. Soc. 1993, 140, 1434. (e) Kodas, T. T.; Hampden-
Smith, M. J . The Chemistry of Metal CVD; VCH Publishers Inc.:
Weinheim, Germany, 1994; Chapter 5.
(9) (a) Partenheimer, W.; J ohnson, E. H. Inorg. Chem. 1972, 11,
2840. (b) Partenheimer, W.; J ohnson, E. H. Inorg. Synth. 1976, 16,
117.
(10) Doyle, G.; Eriksen, K. A.; Van Engen, D. Organometallics 1985,
4, 830.
(5) (a) Dryden, N. H.; Vittal, J . J .; Puddephatt, R. J . Chem. Mater.
1993, 5, 765. (b) Yuan, Z.; Dryden, N. H.; Vittal, J . J .; Puddephatt, R.
J . Chem. Mater. 1995, 7, 1696.
(6) Lin, W.; Warren, T. H.; Nuzzo, R. G.; Girolami, G. S. J . Am.
Chem. Soc. 1993, 115, 11644.
(7) Yuan, Z.; Dryden, N. H.; Li, X.; Vittal, J . J .; Puddephatt, R. J .
J . Mater. Chem. 1995, 5, 303.
(11) Bailey, A.; Corbitt, T. S.; Hampden-Smith, M. J .; Duesler, E.
N.; Kodas, T. T. Polyhedron 1993, 12, 1785.
(12) Xu, C.; Corbitt, T. S.; Hampden-Smith, M. J .; Kodas, T. T.;
Duesler, E. N. J . Chem. Soc., Dalton Trans. 1994, 2841.
S0276-7333(96)00013-1 CCC: $12.00 © 1996 American Chemical Society

2576 Organometallics, Vol. 15, No. 10, 1996
Notes
Ta ble 1. Ch em ica l Sh iftsa of Olefin ic 1H a n d 13C NMR Reson a n ces for VTES a n d Com p ou n d s 1-3
δ (∆δb) (ppm)
H(2)
H(3)
H(1)
C(2)
C(1)
SiEt3
1H
13C
H(1)
6.11
H(2)
H(3)
5.68
C(1)
132.7
C(2)
136.5
VTES
5.98
1
2
3
5.12 (-0.99)
5.14 (-0.97)
4.88 (-1.10)
5.02 (-0.96)
4.92-4.49
4.69 (-0.99)
4.80 (-0.88)
114.0 (-18.7)
112.9 (-19.8)
109.9 (-22.8)
124.0 (-12.5)
121.0 (-15.5)
118.3 (-18.2)
a
b
In C6D6. ∆δ ) δAg complex - δVTES
.
yellow liquids, and 3 is a white solid. They are
moderately sensitive to air, moisture, and light. All
compounds gave satisfactory elemental analyses and
were characterized by solution 1H, 13C, and 19F NMR
and IR spectroscopic methods.
NMR Sp ectr oscop ic Stu d ies of (â-d ik eton a to)Ag-
1
(VTES) Com p lexes. The integrated H and 13C NMR
spectra of the title compounds are consistent with the
empirical formula (â-diketonato)Ag(VTES). Both 1H
and 13C olefinic resonances are upfield relative to those
1
of free vinyltriethylsilane. Comparisons of H and 13C
chemical shifts for the free alkene and the alkene
coordinating to the Ag(I) center were used to investigate
the feature of olefin π-complexation to silver.14,15 Varia-
tions of chemical shifts (∆δ) of olefinic protons and
carbons for compounds 1-3 are listed in Table 1 and
are larger than those for other (â-diketonato)Ag(alkene)
compounds.16 This feature implies the existence of
relatively stronger bonding between the alkene and
silver center in the title compounds.
Sin gle-Cr ystal Str u ctu r al Deter m in ation of Com -
p ou n d 3. Single-crystal X-ray diffraction analysis
reveals that compound 3 is dimeric in the solid state.
An ORTEP diagram showing the atomic labeling scheme
of this molecule is presented in Figure 1. The crystal,
collection, and refinement data are summarized in Table
2; selected bond lengths and bond angles are given in
Table 3. The coordination geometry about silver is best
described as a highly distorted tetrahedron. Each silver
atom is coordinated by the CdC double bond of the
VTES ligand, two oxygen atoms of a chelating fod
ligand, and the methine carbon of another fod ligand.
The same coordination mode for the â-diketonato ligand
is reported in the structure of a dimeric trimethyl(4,6-
nonanedionato)platinum complex.17 The bond distances
and angles within the â-diketonato ligand are similar
to those of other (â-diketonato)silver(I) complexes ac-
cording to previous reports.5,7,12,13 The bond between
Ag and methine C is relatively weak (Ag-C(4) distance
) 2.423(7) Å) compared with those between silver and
F igu r e 1. ORTEP diagram of the molecular structure of
compound 3.
olefinic carbons in the same molecule (Ag-C(1) and Ag-
C(2) bond distances are 2.320(8) and 2.337(9) Å, respec-
tively). The bond distance of CdC in the coordinated
olefin (C(1)-C(2) ) 1.330(13) Å) similar to that of free
alkene indicates weak π-back-bonding between the
alkene and silver center in this compound. No other
distances and angles within the VTES ligand are
exceptional.
Ch em ica l Va p or Dep osit ion of Silver fr om
(h fa c)Ag(VTES). Compound 1 was chosen to under-
take CVD experiments since it can be evaporated at
ambient temperature under reduced pressure. The
experiments were carried out in the hot-wall system
over the deposition temperature range 160-280 °C. The
precursor was vaporized at 30 °C under reduced pres-
sure (0.1 Torr) and was transferred through the deposi-
tion zone. Durations of deposition were 60-120 min,
and the film thicknesses were about 1 µm. Continuous
silver films with a metallic color and resistivities less
than 5 µΩ‚cm were deposited on both Si and SiO2
substrates. All silver films had good adhesion according
to the Scotch tape test. The surface morphology of the
films was determined with SEM; a typical example
deposited on a Si substrate at 220 °C appears in Figure
2. The films consist of continuous grains similar to
those in previous reports.4-7 The grain size increases
with increasing deposition temperature. Needlelike
crystals exist in the films shown in the SEM cross-
(13) Yuan, Z.; Dryden, N. H.; Vittal, J . J .; Puddephatt, R. J . Can. J .
Chem. 1994, 72, 1605.
(14) Lewandos, G. S.; Gregston, D. K.; Nelson, F. R. J . Organomet.
Chem. 1976, 118, 363.
(15) (a) Parker, R. G.; Roberts, J . D. J . Am. Chem. Soc. 1970, 92,
743. (b) Beverwijk, C. D. M.; van Dongen, J . P. C. M. Tetrahedron
Lett. 1972, 4291. (c) van Dongen, J . P. C. M.; Beverwijk, C. D. M. J .
Organomet. Chem. 1973, 51, C36.
(16) ∆δ values of olefinic protons and carbons for (â-diketonato)Ag
complexes of norbornadiene are -0.35 to -0.58 ppm and -0.6 to -5.6
ppm, respectively; for (â-diketonato)Ag complexes of 7-t-BuO-NBD the
values are -0.57 to -0.66 ppm and -10.5 to -16.9 ppm, respectively.
Chi, K.-M.; Chen, K.-H. Unpublished results.
(17) Hargreaves, R. N.; Truter, M. R. J . Chem. Soc. A 1969, 2282.

Notes
Ta ble 2. Su m m a r y of Cr ysta llogr a p h ic Da ta for
Organometallics, Vol. 15, No. 10, 1996 2577
Com p ou n d 3
emp form
fw
C36H54O4Ag2F14Si2
1088.69
cryst size (mm3)
space group
a (Å)
0.10 × 0.40 × 0.50
triclinic; P1h
9.943(3)
b (Å)
11.588(3)
c (Å)
11.802(5)
R (deg)
63.03(3)
81.30(3)
89.56(3)
1195.0(7)
â (deg)
γ (deg)
V (Å3)
Z
1
d(calcd) (g/cm3)
λ (Å)
1.513
0.7107
298
T (K)
F(000)
548
2θ range (deg)
scan type
scan speed (deg/min)
scan width (deg)
2θmax
16.82-24.16
θ/2θ
3.30-8.24
2(0.75 + 0.35 tan θ)
45.0
9.456
µ (cm-1
)
transm
0.905; 1.000
index ranges
-10 < h < 10; 0 < k < 12; -10 < l < 12
a
RF; Rw
0.051; 0.047
1.58
goodness-of-fitb
weighting scheme
refine prog
1/σ2(Fo)
NRCVAX
56
no. of atoms
no. of params refined 263
largest ∆/σ
0.0319
a
RF ) ∑(Fo - Fc)/∑Fo. Rw ) (∑[w(Fo - Fc)2]/∑(wFo2))1/2
.
.
b Goodness-to-fit ) (∑[w(Fo - Fc)2]/(no. of reflcns - no. of params))1/2
F igu r e 2. Scanning electron micrographs of silver film
deposited from (hfac)Ag(VTES) at 220 °C: (a) surface; (b)
cross section.
Ta ble 3. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for Com p ou n d 3
Bond Lengths
d u r es a n d Sta r tin g Ma ter ia ls. All operations were per-
formed under an atmosphere of nitrogen purified by passage
through columns of activated BASF catalyst and molecular
sieves and using standard Schlenk techniques18 in conjunction
with a double-manifold vacuum line. Diethyl ether and hexane
were dried and distilled from sodium benzophenone ketyl at
atmospheric pressure before use. Silver(I) oxide, 1,1,1,5,5,5-
hexafluoro-2,4-pentanedione, 1,1,1-trifluoro-2,4-pentanedione,
2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedione, and vin-
yltriethylsilane (Aldrich Chemical Co.) were used without
further purification. Elemental analyses were made at the
National Science Council Southern Instrument Center (De-
partment of Chemistry, National Cheng Kung University).
NMR data were recorded on a Varian Gemini-200 NMR
spectrometer by using the protio impurities of deuterated
Ag-O(1)
Ag-C(1)
Ag-C(4)
O(2)-C(5)
C(3)-C(4)
2.312(5)
2.320(8)
2.423(7)
1.237(9)
1.438(10)
Ag-O(2)
2.356(5)
2.337(9)
1.251(9)
1.330(13)
1.402(10)
Ag-C(2)
O(1)-C(3)
C(1)-C(2)
C(4)-C(5)
Bond Angles
O(1)-Ag-O(2)
O(1)-Ag-C(2)
O(2)-Ag-C(1)
O(2)-Ag-O(4)
C(1)-Ag-C(4)
Ag-O(1)-C(3)
Ag-C(1)-C(2)
Si-C(2)-C(1)
C(3)-C(4)-C(5)
77.90(17)
99.5(3)
O(1)-Ag-C(1)
O(1)-Ag-O(4)
O(2)-Ag-C(2)
C(1)-Ag-C(2)
C(2)-Ag-C(4)
Ag-O(2)-C(5)
Ag-C(2)-C(1)
O(1)-C(3)-C(4)
O(2)-C(5)-C(4)
128.9(3)
104.08(22)
116.6(3)
33.2(3)
140.4(3)
123.5(5)
72.7(5)
130.3(3)
99.27(22)
109.9(3)
130.5(5)
74.1(5)
126.5(8)
121.6(7)
125.0(7)
133.1(7)
1
solvents as references for the H NMR and the 13C signals of
the solvents as references for 13C NMR spectroscopies. 19F
NMR spectra were externally referred to CFCl3. Infrared data
were recorded on a Perkin-Elmer Model 16 PC FTIR spectro-
photometer.
section picture (Figure 2b). This crystallinity was
confirmed by X-ray diffraction analyses. A diffraction
pattern of a film deposited at 220 °C (Figure 3) corre-
sponds to cubic silver. The compositions of the depos-
ited films were characterized by Auger electron spec-
troscopic analyses. Purities of all silver films are
greater than 96% with a trace of oxygen contamination.
In summary, we prepared new silver complexes of
empirical formula (â-diketonato)Ag(VTES). All com-
pounds were characterized by analytical and spectral
methods. The structure of (fod)Ag(VTES) was deter-
mined by single-crystal X-ray diffraction analysis. CVD
experiments using (hfac)Ag(VTES) as a precursor dem-
onstrated deposition of pure silver films at temperatures
above 160 °C.
a . (h fa c)Ag(VTES) (1). Vinyltriethylsilane (4.0 mL, 21.6
mmol) was transferred to a 250-mL Schlenk flask containing
a suspended solution of Ag2O (2.50 g, 10.8 mmol) in diethyl
ether (50 mL). Then, a solution of hfacH (3.2 mL, 21.6 mmol)
in Et2O (20 mL) was added dropwise to the reaction flask with
stirring and the reaction mixture turned yellow immediately.
The mixture was stirred for 4 h at room temperature. The
volatile components were removed in vacuo (0.1 Torr), and
hexane (80 mL) was added to dissolve the product. After
filtration and removal of hexane, a bright yellow liquid product
was obtained in 82% yield (8.12 g).
Anal. Calcd for
C13H19O2F6AgSi: C, 34.15; H, 4.19.
Found: C, 33.77; H, 4.18. NMR data (C6D6, 18 °C): 1H δ 6.09
(s, 1H, CH on hfac), 5.12 (dd, J H-H ) 19.1, 13.8 Hz, 1H,
CH2dC(H)SiEt3 on VTES), 4.88 (dd, J H-H ) 13.8, 4.6 Hz, 1H,
Exp er im en ta l Section
Syn th eses a n d Ch a r a cter iza tion of (â-Dik eton a to)-
silver Vin yltr ieth ylsila n e Com p lexes. Gen er a l P r oce-
(18) Shriver, D. F.; Drezden, M. A. The Manipulation of Air-Sensitive
Compounds, 2nd ed.; Wiley: New York, 1986.

2578 Organometallics, Vol. 15, No. 10, 1996
Notes
F igu r e 3. XRD pattern of silver film deposited from (hfac)Ag(VTES) at 220 °C.
CHdC(H)SiEt3 on VTES), 4.69 (dd, J H-H ) 19.1, 4.6 Hz, 1H,
CHdC(H)SiEt3 on VTES), 0.80 (t, J H-H ) 7.8 Hz, 9H, CH3 on
VTES), 0.39 (q, J H-H ) 7.7 Hz, 6H, CH2 on VTES) ppm. 13C-
{1H}: δ 177.8 (q, J F-C ) 32.3 Hz, CF3CO on hfac), 124.0 (s,
CH2dC(H)SiEt3 on VTES), 118.4 (q, J F-C ) 291.6 Hz, CF3 on
hfac), 114.0 (s, CH2dC(H)SiEt3 on VTES), 87.6 (s, CH on hfac),
7.1 (s, CH3 on VTES), 3.4 (s, CH2 on VTES) ppm. 19F{1H}: δ
-76.8 (s) ppm. IR data (KBr disk) (νCO): 1663 (s), 1557 (m),
from ref 19. The final agreement factors are RF ) 0.051 and
Rw ) 0.047 with w ) 1/σ2(Fo). Crystal, collection, and
refinement data are summarized in Table 2.
Ch em ica l Va p or Dep osition of Silver F ilm s fr om
Com p ou n d 1. CVD experiments were conducted in a hot-
wall reactor reported previously.20 Silicon(100) wafers coated
with 2000 Å of thermally grown SiO2 were used as substrates.
The substrates, typically 1.5 cm × 1.5 cm2, were cleaned with
deionized water, acetone, and 1,1,1-trichloroethane and then
heated to 100 °C for 20 min before use. The CVD reactor was
charged with approximately 0.5 g of (hfac)Ag(VTES) and a
substrate in a glovebox with nitrogen atmosphere for each
experiment. The assembled reactor was attached to a U-trap
that was cooled with liquid N2 and connected to a vacuum line.
While the system was evacuated (0.1 Torr), the precursor was
cooled with dried ice to prevent its evaporation and the
deposition zone was preheated with a furnance for 1 h to attain
the deposition temperature. The precursor remained at room
temperature. The precursor was then warmed to 30 °C with
a heating tape to transfer into the deposition zone, and
deposition was continued until all precursor had evaporated.
Deposition was undertaken over a temperature range 160-
280 °C at 30 °C intervals. No carrier gas was used in these
experiments.
1536 (m), 1493 (s), 1473 (s) cm-1
.
(b ). (t fa c)Ag(VTE S) (2). Pale yellow, liquid (tfac)Ag-
(VTES) was prepared in 85% yield with a procedure analogous
to that of synthesis of compound 1.
Anal. Calcd for
C13H22O2F3AgSi: C, 38.72; H, 5.50.
Found: C, 38.97; H, 5.33. NMR data (C6D6, 18 °C): 1H δ 5.62
(s, 1H, CH on tfac), 5.14 (dd, J H-H ) 17.4, 13.8 Hz, 1H, CH2dC-
(H)SiEt3 on VTES), 5.02 (dd, J H-H ) 13.8, 6.0 Hz, 1H, CHdC-
(H)SiEt3 on VTES), 4.80 (dd, J H-H ) 17.4, 6.0 Hz, 1H,
CHdC(H)SiEt3 on VTES), 1.82 (s, 3H, CH3 on tfac), 0.84 (t,
J H-H ) 7.7 Hz, 9H, CH3 on VTES), 0.45 (q, J H-H ) 7.6 Hz, 6H,
CH2 on VTES) ppm. 13C{1H}: δ 198.4 (s, CH3CO on tfac),
172.1 (q, J F-C ) 30.6 Hz, CF3CO on tfac), 121.0 (s, CH2dC-
(H)SiEt3 on VTES), 119.6 (q, J F-C ) 285.9 Hz, CF3 on tfac),
112.9 (s, CH2dC(H)SiEt3 on VTES), 91.8 (s, CH on tfac), 29.8
(s, CH3 on tfac), 7.3 (s, CH3 on VTES), 3.6 (s, CH2 on VTES)
ppm. 19F{1H}: δ -75.4 (s) ppm. IR data (KBr disk) (νCO):
1636 (s), 1530 (m), 1473 (s) cm-1
.
Deposited films were characterized by surface analysis
methods described as follows. Scanning electron micrographs
(c). (fod )Ag(VTES) (3). White, crystalline (fod)Ag(VTES)
was prepared in 88% yield following a procedure similar to
that of synthesis of compound 1.
were obtained on
a J EOL J SM-5400 instrument. X-ray
diffraction patterns were detected by a MAC Science MXP3
powder diffractometer with Cu KR radiation (λ ) 1.5045 Å).
Auger electron spectroscopic analyses were made on a Fison
Microlab 310D instrument at the National Science Council
Southern Instrument Center (Department of Material Science,
National Cheng Kung University). Film resistivities were
measured with a four-point probe.
Anal. Calcd for
C18H28O2F7AgSi: C, 39.64; H, 5.18.
Found: C, 39.45; H, 5.14. NMR data (C6D6, 18 °C): 1H δ 6.02
(s, 1H, CH on fod), 4.92-4.49 (m, 3H, CH2dC(H)SiEt3 on
VTES), 1.16 (s, 9H, C(CH3)3 on fod), 0.83 (t, J H-H ) 7.8 Hz,
9H, CH3 on VTES), 0.42 (q, J H-H ) 7.9 Hz, 6H, CH2 on VTES)
ppm. 13C{1H}: δ 206.7 (s, (CH3)3CO on fod), 173.0 (q, J F-C
)
21.2 Hz, C3F7CO on fod), 121.7-103.6 (m, CF2CF2CF3 on fod),
118.3 (s, CH2dC(H)SiEt3 on VTES), 109.9 (s, CH2dC(H)SiEt3
on VTES), 89.5 (s, CH on fod), 42.9 (s, C(CH3)3 on fod), 28.1
(s, C(CH3)3 on fod), 7.3 (s, CH3 on VTES), 3.4 (s, CH2 on VTES)
ppm. 19F{1H}: δ -80.7 (s), -118.6 (s), -126.3 (s) ppm. IR
data (KBr disk) (νCO): 1631 (s), 1520 (m), 1478 (s) cm-1. Mp:
70 °C (dec).
X-r ay Sin gle-Cr ystal Str u ctu r al Deter m in ation of Com -
p ou n d 3. White crystals of (fod)Ag(VTES) were grown by
crystallization from diethyl ether solution at -20 °C, and a
single crystal of dimensions 0.10 × 0.40 × 0.50 mm3 was
selected for X-ray analysis. All diffraction data were collected
on an Enraf-Nonius CAD-4 diffractometer with monochro-
mated Mo KR radiation (λ ) 0.7107 Å) using θ/2θ scan mode.
Cell parameters were determined from 25 reflections (16.82
< 2θ < 24.16°). All data were corrected for Lorentz and
polarization effects and for effects of absorption. A total of
3124 reflections were collected, but only 2094 unique reflec-
tions with I > 2σ(I) were used for structural solution and
refinement. The structure was solved by the heavy-atom
method and refined by full-matrix least squares based on F
values. All non-hydrogen atoms were refined with anisotropic
thermal parameters. The atomic scattering factors were taken
Ack n ow led gm en t. We thank Miss H.-F. Wang for
obtaining XRD data, Dr. S.-G. Shyu of the Institute of
Chemistry, Academia Sinica, for obtaining SEM data,
and the National Science Council of the Republic of
China (NSC 83-0208-M-194-003) and National Chung
Cheng University for financial support of this work.
Su p p or tin g In for m a tion Ava ila ble: Crystallographic
data for compound 3, including tables of crystal data, atomic
coordinates and B values, bond distances and angles, and
anisotropic thermal parameters and text describing X-ray
procedures (12 pages). Ordering information is given on any
current masthead page.
OM960013E
(19) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, U.K., 1974; Vol. IV.
(20) Chi, K.-M.; Hou, H.-C.; Hung, P.-T.; Peng, S.-M.; Lee, G.-H.
Organometallics 1995, 14, 2641.