conf�rence Karlovy Vary by T4nRGwP

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									            XVI ICF TECHNICAL EXCHANGE
                     CONFERENCE
                   9th-12th October 2004
                       Karlovy Vary

            Study of
some gilded film/glass interfaces
             and of
one standard type of “liquid gold”

Evelyne Darque-Ceretti, Doriane Hélary, Virginie Deram

                  Ecole des Mines de Paris
          Centre de Mise en Forme des Matériaux
                     UMR CNRS 7635
                     Sophia-Antipolis
                          France
        Composition of precious metal preparations



                                       precious metals


                                       auxiliary
                                       materials
                                       solvents


                                       fixing agents


                                       adhesion
                                       promoters

 XIV Technical Exchange Conference Waterford, Ireland
               October 12 th – 14 th 2002
Annette Lukas/ Ceramic Colour Division Heraeus Germany
                                                      Introduction



Thin gilded films from organo-metallic solutions are used to
                    decorate glass objects

           Organo-metallic solution = “liquid gold”


                        Objectives:
          1. Analysis of interactions after firing
          between gold and glass, (treated or no)

    2. Characterization of another type of “liquid gold”
                before and during firing
Part 1: Gilded film /glass


Specimen
Characterization methods
Surfaces observation
Interfacial reactions
Conclusions
                                                Specimen

                    Substrates
                  soda-lime glass
                    untreated
                         or
      treated with a Ti oxide film (~ 6 nm thick)
          or a Sn oxide film (~ 8 nm thick)

                    Gold films

            - organometallic preparation with 12 % of
metallic Au + small metal additions (Rh, Ag, V, Zr …)
     - deposition on the substrate and firing in air at
               ~ 600°C during 15 min
                 ~ 0.1-0.2 µm thick
                         Characterisation methods - Why use them ?



Scanning Electron Microscope (SEM)
      morphology (SE mode) and atomic contrast (BSE
      mode) of the specimen surfaces

Secondary Ion Mass Spectrometry (SIMS)
     Depth distribution of elements (C, Au, Ti, Si, …) with
     great sensitivity but problems due to charge effects
     in the glass substrate

Glow Discharge Optical Emission Spectrometry (GDOES)
with radio frequency
      Depth distribution for all elements without charge
      effects
                                     SEM surfaces observation
  Sn treated glass
        BSE mode           For all specimen surfaces :

                                Non continuous gold
                                       distribution

                            Formation of an agglomerated
                                     structure

        SE mode



                                Rough surface
                                 Ra ~ 0.4 µm




Firing temperature 600°C
                                                                                                               Interfacial reactions
     SIMS analysis :                                                             Sn treated glass
In negative secondary mode
                                                                                                                        Charge
                                                                                                                        effects
          Secondary ion intensity (a.u)


                                              12 C (*1000)
                                                                         197 Au (*50)          28 Si (*100)




                                                        120 Sn (*1000)


                                                        107 Ag (*1000)

                                          0       100           200           300       400   500        600     700     800
                                                                                                                        Time (s)
                                               Film ~ 0.2 µm                                        Glass substrate
                                                                      Intermediate zone
  - Gold diffusion into the substrates
  - Tin diffusion preferentially into the gilded film
  - Contamination by hydrocarbons (C)
  - Silicon diffusion to the surface
                       Distribution of Au diffused into Sn or Ti                                                        Interfacial reactions

                           treated or untreated glass at 600°C
                                                         Fitting by the second Fick’s law :
                       1
Normalised intensity




                                           Au diffusion until
                                Au diffusion until 0.15 µm 0.15 µm                                         1
                                                                                                                      Au diffusion until 0.75 µm




                                                                                     Normalsed intensity
                       0
                        0,00 0,03 0,05 0,08 0,10 0,13 0,15 0,18 0,20 0,23 0,25
                                                                                                           0
                               Distance from interlayer/glass interface (µm)                                   0    0,25     0,5     0,75     1      1,25     1,5
                                                                                                               Distance from gilded film /glass interface (µm )

                              pre-treated
                           TiTi,Sn
Quite the same DAu for Ti or Sn pre-treated glass
                 at 600 °C :

D Au treated glass  2.4 10-14 cm2/s                                            DAu untreated glass  4 10-13 cm2/s

                                           Gold diffuses faster into untreated glass
                                         Intermediate oxide layer = diffusion barrier
                                                                                                                                    Interfacial reactions
Rf-GDOES analysis :                                                Ti treated glass




                                                                                  intensity (a.u)
intensity (a.u)




                                                                                                                                           Si/2
                                                                                                            Au*2

                              Au*2
                                                                Na

                                                                                                                                                  O*2
                                             Ca/2                                                                                                         H*2

                                                                K*2                                                            Ti
                                               Ti
                  0,049      1,049   2,049    3,049   4,049    5,049
                                                                       Time (s)                     0,049     1,049    2,049   3,049    4,049     5,049   Time (s)
                            Film      Intermediate                                                            Film       Intermediate
                                                          Glass substrate
                          ~ 0.2 µm        zone                                                              ~ 0.2 µm         zone           Glass substrate
                   - Migration of alkali constituents of the base glass in the film with
                   segregation at the extreme surface
                   - Gold diffusion into the substrates
                   -Titanium diffusion preferentially into the gilded film
                   - Contamination by hydrocarbons (H)
                   - Oxidation of the gilded layer (due to the thermal treatment in air)
                    Conclusions
- For (600°C) faster Au diffusion into untreated glass
DAu  4 10-13 cm2/s than pre-treated glass DAu  2.4 10-14
cm2/s
         Ti and Sn interlayers act as a diffusion barrier

- Ti and Sn diffusion into the gold film and into the glass
         formation of compounds Au-Ti or Au-Sn ?

- Diffusion of alkali components from the glass into the
gold film
          formation of compounds ?

- Substantial presence of O in the gilded zone
         formation of a gold oxide ?
Part 2: Characterization of a “liquid-gold”

Specimen

In-situ observations and analyses during the heating
process

Conclusions
Our liquid gold

Solid resin

in situ analytical methods                          500m



Optical microscope, X-ray diffraction, and thermal methods
(differential scanning calorimeter and gravimetric analysis)

Sequential methods
Scanning electron microscope, energy dispersive spectrometry
FTIR spectroscopy
Optical Microscope + Thermo-Gravimetric Analysis


                              1 mm
                              1 mm                   1 mm
                                                     1 mm                  1 mm
                                                                           1 mm                1 mm
                                                                                               1 mm           1 mm
                                                                                                              1 mm




25°C                                   65°C                   200°C                  350°C            450°C


                    0                                                                                           mm
                                                                                                              1 mm

                   -10
 weight loss (%)




                   -20
                                                                                                      600°C
                                                                 Metallic film formation
                   -30         Drying phase                      smoothing, spreading
                   -40
                              Evaporation of
                             the solvent mix
                   -50

                   -60

                   -70                             Thermal decomposition
                                                      of the resinates
                   -80
                         0     50    100 150 200    250 300 350 400    450 500 550   600 650

                                                    temperature (°C)
 Reflectance FTIR




                    Transmittance
 25°C - 150°C :
                                                                                      630°C
                                                                                      530°C
  Loss of                                                                             430°C
                                                                                      330°C
  hydrocarbons                                                                        280°C
                                                                                      230°C

 150°C - 330°C :                                                                     180°C
                                                                                      130°C
   C=O vibration                                                                     25°C

  Decomposition
  of R-SO2-OR'
  groups                   500      1000   1500   2000   2500    3000
                                                                -1
                                                                        3500   4000

                                              wave number (cm )
 Above 350°C :
                                R-SO2-OR'            C=O                    C-H
  Thin film                      groups            vibration             vibration
  formation
X-Ray diffraction

                                                  300°C  650°C
                                                       FWHM
                                                  Increase of gold
                                                   crystallite size

    300°C
Crystalline gold
                                                                                                                      650°C
                                                                                                                      600°C
 Amorphous                                                         650
                                                                  600
                                                                                                                      550°C




                                                                         temperature (°C)
                                                                  550                                                 500°C
   resins                                                         500
                                                                  450
                                                                  400
                                                                                                                      450°C
                                                                 350                                                  400°C
                                                                 300
                                                                 250                                                  350°C
                                                                 200                                                  300°C
                                                                150
           0   10                                               100
                    20   30                                                                 35        40         45
                              40   50                           50
                                        60   70
                          2theta (de              80   90 100   0                                2 theta (degrees)
                                    grees)
Complementary analysis : EDS

                       Surface analysis after firing

           100

            80
                                                                  Liquid gold after screen-printing
                                                             C
atom (%)




                                                             O
            60
                                                                         Thickness  50 m
                                                             S
            40                                               Ag                  HEATING
                                                             Au
            20

             0
                 100     200    300    400       500   600
                               temperature ( °C)




                                                                  600°C : Heterogeneous film
                                                                     Thickness  150 nm
                  Conclusions

- Critical temperature 300°C
      Existence of the first gold crystallites

- From 300°C to 600°C,
      Gold recrystallisation and grain growth
      Oxidation or decomposition of some componds :V,Rh?
      Smoothing and spreading of the film
      Interdiffusion of gold into the glass and alkali
elements into the gilded film (part 1)

    What is the effect on adhesion properties?

								
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