Phosphane and phosphite silver(I) complexes [Elektronische Ressource] : synthesis, reaction chemistry and their use as CVD precursors / vorgelegt von Patrice Djiele Ngameni

Joseph Rodolph

Description

Phosphane and Phosphite Silver(I) Complexes: Synthesis, Reaction Chemistry and their Use as CVD Precursors von der Fakultät für Naturwissenschaften der Technische Universität Chemnitz genehmigte Dissertation Zur Erlangung des akademischen Grades doctor rerum naturalium (Dr. rer. nat.) Vorgelegt von M.Sc. Patrice DJIELE NGAMENI Geboren am 29.04.1973 in Fondjomekwet, Kamerun Eingereicht am 09.11.2004 Gutachter: Prof. Dr. Heinrich Lang Prof. Dr. Stefan Spange Prof. Dr. Katharina Kohse-Höinghaus Tag der Verteidigung: 27.01.2005 http://archiv.tu-chemnitz.de/pub/2005/0008 Bibliographische Beschreibung und Referat DJIELE NGAMENI, Patrice Phosphane and Phosphite Silver(I) Complexes: Synthesis, Reaction Chemistry and their Use as CVD Precursors Technische Universität Chemnitz, Fakultät für Naturwissenschaften Dissertation, 2004, 144 Seiten Silber(I) Komplexe LAgX (X = organische Ligand, Z. B. nCarboxylate, Dicarboxylate, Schiff Base; L = Lewis-Base, Z. B. nP Bu, P(OMe), P(OEt); n = 1, 2, 3) wurden Bezug auf ihre 3 3 3Eignung für die chemische Gasphasenabscheidung von Silberfilmen synthetisiert und charakterisiert. Von einigen dieser Verbindung konnten Einkristalle erhalten werden. Der Bau dieser Verbindungen wurde mittels Röntgeneinkristallographie ermittelt. Ausgewählten Verbindungen wurden mit Temperatur-programmierter und in-situ Massenspektrometrie analysiert.

Informations

• Publié par: technische_universitat_chemnitz
• Publié le: 01 janvier 2005
• Nombre de lectures: 129
• Langue: Deutsch
• Poids de l'ouvrage: 2 Mo

Extrait

Phosphane and Phosphite Silver(I) Complexes: Synthesis, Reaction Chemistry and their Use as CVD Precursors

von der Fakultät für Naturwissenschaften der Technische

Universität Chemnitz

genehmigte Dissertation Zur Erlangung des akademischen Grades

doctor rerum naturalium (Dr. rer. nat.) Vorgelegt von M.Sc. Patrice DJIELE NGAMENI

Geboren am 29.04.1973 in Fondjomekwet, Kamerun Eingereicht am 09.11.2004 Gutachter: Prof. Dr. Heinrich Lang  Prof. Dr. Stefan Spange  Prof. Dr. Katharina Kohse-Höinghaus Tag der Verteidigung: 27.01.2005 http://archiv.tu-chemnitz.de/pub/2005/0008

Bibliographische Beschreibung und Referat

Bibliographische Beschreibung und Referat DJIELE NGAMENI, Patrice Phosphane and Phosphite Silver(I) Complexes: Synthesis, Reaction Chemistry and their Use as CVD Precursors

Technische Universität Chemnitz, Fakultät für

Naturwissenschaften

Dissertation, 2004, 144 Seiten Silber(I) Komplexe L n AgX (X = organische Ligand, Z. B. Carboxylate, Dicarboxylate, Schiff Base; L = Lewis-Base, Z. B. n P Bu 3 , P(OMe) 3 , P(OEt) 3 ; n = 1, 2, 3) wurden Bezug auf ihre Eignung für die chemische Gasphasenabscheidung von Silberfilmen synthetisiert und charakterisiert. Von einigen dieser Verbindung konnten Einkristalle erhalten werden. Der Bau dieser Verbindungen wurde mittels

Röntgeneinkristallographie ermittelt. Ausgewählten Verbindungen wurden mit Temperatur-programmierter und in-situ Massenspektrometrie analysiert. Gasphasenabscheidungs-

mechanismen für einige Prekursoren sind vorgestellt. CVD- Abscheidungsexperimente wurden entsprechend den Ergebnissen der Gasphaseanalyse durchgeführt. Silber Schichten konnten mit einen Kaltwand CVD-Reaktor erzeugt werden, deren Oberflächenmorphologie wurde untersucht. Stichworte: Silber, Silber(I)-Carboxylate, Disilber(I)- Dicarboxylate, Schiff-Base, Synthese, Einkristall- röntgensstrukturen, Chemische Gasphasenabscheidung,

Massenspektrometrie, Oberflächen-Analytik.

Abstract Phosphane and Phosphite Silver(I) Complexes: Synthesis, Reaction Chemistry and their Use as CVD Precursors by M. Sc. DJIELE NGAMENI, Patrice

Chairman: Prof. Dr. LANG, Heinrich Abstract

Silver(I) complexes of type L n AgX (X = organic ligand, such as carboxylates, dicarboxylates, Schiff-base; L = Lewis- n bases, e. g. P Bu 3 , P(OMe) 3 , P(OEt) 3 ; n = 1, 2, 3) have been synthesized and characterized with respect to their suitability for the Chemical Vapour Deposition (CVD) of silver thin films. For some of these compounds single crystal could be obtained. Their solid-state structure was determined by single crystal X-ray diffraction. The volatility, thermal stability, and gas phase decomposition mechanism of selected

compounds were studied using temperature-programmed and in- situ mass spectrometry. CVD experiments were performed according to the results of the gas phase analysis. Silver films could be grown by using a cold-wall CVD reactor. The morphology of the latter films was determined. Keywords: Silver, Silver(I)-Carboxylates, Bisilver(I)- Dicarboxylates, Schiff-base, Synthesis, Solid-state structure, Chemical Vapour Deposition (CVD), Mass spectrometry, Deposition studies.

Dedication

To my parents and my grandmother

43

n Synthesis of Silver(I)-Carboxylates of type [( Bu 3 P) 3 AgX] and 37 [{(OR) 3 P} 3 AgX] (R = Me, Et)

3.3

n n 3.5.1 Spectroscopic studies of [( Bu 3 P) m AgEAg(P Bu 3 ) m ] complexes

3.4.2 TG and DSC studies of complexes

3.5

3.2

3.2.1 Spectroscopic complexes

3.4.1 Spectroscopic studies of complexes

n studies of [( Bu 3 P)AgX] and [{(OR) 3 P}AgX] 21

and

[{(OR) 3 P}AgX] 18

3.4

n [( Bu 3 P) 3 AgX] and [{(OR) 3 P} 3 AgX] 38

of Silver(I)-Carboxylates and - 14

Synthesis of Phosphane- and Phosphite-stabilized 11 n silver(I) complexes of type: [( Bu 3 P) m AgX], n n [{(OR) 3 P} m AgX], [( Bu 3 P) m AgEAg(P Bu 3 ) m ] (m = 1, 2, 3; R = Me, Et; X = Carboxylate, E = Dicarboxylate) Synthesis of Silver(I)-Carboxylates [AgX] and - 12 Dicarboxylates [AgEAg]

3.3.1 Spectroscopic studies of complexes

3.2.2 TG and DSC complexes

n n Synthesis of Silver(I) Dicarboxylates [( Bu 3 P) m AgEAg(P Bu 3 ) m ]42 (m = 1,2,3)

Table of Contents

n [( Bu 3 P) 2 AgX] and [{(OR) 3 P} 2 AgX] 27

Abbreviations

1

Introduction

n Synthesis of Silver(I)-Carboxylates of type [( Bu 3 P) 2 AgX] and 26 [{(OR) 3 P} 2 AgX] (R = Me, Et)

2

30

3

n [( Bu 3 P) 2 AgX] and [{(OR) 3 P} 2 AgX] 33

8

1

3.3.3 TG and DSC studies of complexes

5

3

3.1

of

3.3.2 Solid-state Structure of11C

n [( Bu 3 P) 3 AgX] and [{(OR) 3 P} 3 AgX] 40

studies

n [( Bu 3 P)AgX]

n Synthesis of Silver(I)-Carboxylates of type [( Bu 3 P)AgX] and 16 [{(OR) 3 P}AgX] (R = Me, Et)

3.1.1 Spectroscopic studies Dicarboxylates

State-of-Knowledge

124

77

76

72

142

139

131

127

64

58

58

55

72

69

67

67

50

52

50

Device Description

6.2

Film Characterization

n 4.2 Synthesis of the Bu 3 P Silver(I) Schiff-base of type n [( Bu 3 P) m Ag{O-2-(C 6 H 4 )C(H)N(C 6 H 4 )-4-R}] 4.2.1 Spectroscopic studies

144

4.2.3 5 5.1 5.2 6

Synthesis of Silver Schiff-base complexes of type: 47 n [( Bu 3 P) m Ag{O-2-(C 6 H 4 )C(H)N(C 6 H 4 )-4-R}] (R = OMe, Me; m = 1, 2) Synthesis of Silver(I) Schiff-base Complexes47

6.1

2

45

4.1.1 Spectroscopic studies

Table of Contents n n 3.5.2 TG and DSC studies of [( Bu 3 P) m AgEAg(P Bu 3 ) m ] complexes

4.1

8

7.4

TD and DSC studies Mass Spectrometric Investigations Temperature-programmed Mass Spectrometry In-situ Time-of-Flight Mass Spectrometry CVD Experiments

4.2.2 Solid-state structure of21aand21b

Selbständigkeitserklärung

9

7.3

Acknowledgement

Synthesis Procedure and Experimental Data

Starting Materials

Crystal Refinement Data

Summary References Personal Data

Instruments and Measurements Conditions

Experimental Section

4

7

7.1

7.2

48

Abbreviations

Abbreviations Angström Chemical Vapour Deposition n n-Butyl, C 4 H 9 Ethyl, CH 3 CH 2 Methyl, CH 3 Dimethylsulfoxide, (CH 3 ) 2 SO Dimethylformamide, HCON(CH 3 ) 2 Diethyl ether Tetrahydrofuran Minute Melting point Triethylamine, N(C 2 H 5 ) 3 Phenyl, C 6 H 5 Milliliter Lewis-base -3 Standard cubic centimeter, cm Electron Volt Kelvin Kilo Volt Celsius Millisecond Millimeter Nanometer X-RayDiffraction ScanningElectronMicroscopy Joule Gramm Equation Thermogravimetry Temperature at the beginning of measurement Temperature at the end of measurement Weight loss (%) DifferentialScanningCalorimetry Enthalpy (J/g) About For example compound Temperature Temperature of evaporation

Å CVD n Bu Et Me DMSO DMF Et 2 O THF min Mp NEt 3 Ph mL L sccm eV K kv C ms mm nm XRD SEM J g Eq TG T begin T end ∆m DSC ∆H Ca. e. g. Compd. Temp. T evap

3

IR

ν -1 cm w m s vs

NMR

δ s bs d m t q

Abbreviations Infrared Stretching frequency Wave number Weak Medium Sharp VerySharp

NuclearMagneticResonance Chemical shift Singlet Broadsignal Dublet Multiplet Triplet Quartet

4

1 Introduction

Theoretical Section

5

 Silver has many properties that make it a very useful and precious metal. Of all metals, silver exhibits, for example,

the lowest resistivity and the highest thermal conductivity at room temperature [1]. For these reasons silver has been studied as potential interconnect material forUltraLarge ScaleIntegration (ULSI) technology. It also has potential applications in optoelectronic-mechanical systems and reflexive mirror arrays [2-6].  Several processes such as sputtering [7], electron beam evaporation [8], molecular beam epitaxy [9], photochemical deposition [10] andChemicalVapourDeposition (CVD) [11] have

been investigated for the growth of silver thin films. CVD has

a number of key advantages in depositing metal films; it allows the performance of coatings on large surface areas, high film uniformity, good deposition control, high deposition rates and excellent conformal step coverage on device

structures with dimension below 2µm, which are important in microelectronic applications [11,12].  The production of a desired thin film material via CVD requires an integrated approach involving the selection of the precursor and the deposition technique. The general characteristics of an ideal precursor can be summarized as follows: -Volatility: the precursor should have a good volatility and thermal stability during its evaporation and transportation in the gas phase.

-Purity and reactivity: the precursor should be of high purity and decompose cleanly on pyrolysis without decomposition byproducts. -Stability: the precursor should be stable in its storage container over a long period of time (ca. 6 months).

-Cost: the precursor should be available in consistent quality

and quantity at low cost [2,13].

Theoretical Section 6 A good understanding of CVD exists for some metals, particularly for tungsten, aluminium and copper [2]. For example a large number of Cu(I) precursors of general formula

L n Cu(I)X (X = alkyl, alkoxy,β-diketonate,β-ketoiminate, …; L = Lewis-base, phosphine, olefin, alkyne; n = 1, 2, 3) are well TM known [14,15]. (Vtms)Cu(hfac) (Cupra Select ) [16-18] is the Commercial available Cu(I) precursor.

It is anticipated that there will be a need to change the interconnect material from aluminium or tungsten to new ultrafast materials in microelectronic circuitry. In this respect, silver is an excellent choice, since it exhibits

lower resistance (copper≈ 1.7µΩcm,

silver≈ 1.6µΩcm,

aluminium≈ 2.7µΩcm) [2] and good electromigration performance [19-21]. On the other hand, silver complexes are inexpensive and provide economical alternative to more expensive metal precursors. However, there have only been few

investigations into silver CVD. A great deal of research is still necessary, because up to now there is no general agreement on the deposition method, the precursor choice and

the gas phase decomposition mechanism in silver CVD.  The purpose of this study was to synthesize new organo- silver(I) complexes and to test them as suitable precursor in

silver CVD. Potential organic ligand which have been used are carboxylates, dicarboxylates and Schiff-bases. As lewis-base n P Bu 3 , P(OMe) 3 , and P(OEt) 3 were applied. In Section 3, the synthesis of phosphane and phosphite n stabilized silver(I) complexes of type ( Bu 3 P) m AgX, [P(OR) 3 ] m AgX n n and ( Bu 3 P) m AgEAg(P Bu 3 ) m  (m = 1,2,3; R = Me, Et; X = carboxylates; E = dicarboxylates) is discussed. The preparation of the phosphane-stabilized silver(I) Schiff-base n complexes [( Bu 3 P) m Ag{O-2-(C 4 H 6 )C(H)N(C 4 H 6 )-4-R}] (R = OMe, Me;

m = 1, 2) will be discussed in Section 4.

Theoretical Section 7 These complexes have been characterized by elemental 1 13 1 31 1 analysis, IR, H-, C{ H}-, P{ H}-NMR spectroscopy. The thermal behaviour of the respective silver(I) complexes was investigated using thermogravimetric and differential scanning

calorimetric analysis. The obtained single crystals of some species have been characterized by X-ray diffraction studies. The gas phase study of selected complexes was carried out using temperature-programmed and in-situ time-of-flight mass spectrometry. The presence of silver-containing fragments was

used to indicate their volatility and several compounds were regarded as potentially suited for CVD applications. The quality and the microstructure of silver thin films deposited using a vertical cold-wall reactor with a pulsed spray evaporation system is discussed.