Authors:M. Bahra, D. Elliott, M. Reading, and R. Ryan
A novel instrument is described called the Thin film Analyser (TFA) which quantitatively measures changes in mechanical and rheological properties of drying films in-situ on a test panel. It is based around a simple force-sensing device, capable of carrying various probes, which can be positioned in anX-Y plane over the panel. Temperature control is achieved by means of a heating block under the sample. By imposing a thermal gradient along the block, measurements can be obtained at a series of temperatures in a single experiment. Several applications of the TFA to the drying of curable and latex-based coatings are discussed, as well as some more specialized uses. The TFA concept represents a novel approach to the thermal analysis of thin films.
Thermoanalytical (TA) methods are relatively seldom applied for assessing the physical and chemical proeprties of thin films,
but they can be used in studies of composition, phase transitions and film—substrate interactions. In the present paper the
possibilities of TA methods in thin film studies are reviewed. The thermoanalytical methods considered are the classical TG
and DTA/DSC methods but some complementary methods will also be briefly mentioned. The main emphasis is given to true thin
films. Details of sample preparation are also given. An important application of TA methods is characterization of precursors
for the CVD growth of thin films, and this is also discussed.
Processing thin films for advanced applications, for instance in electronics and optoelectronics, involves several steps starting
from precursor synthesis and ending up with the devices. Especially when optimizing the first steps of this chain of processes,
thermoanalytical techniques play an important role. The review will focus on the main chemical deposition methods (CVD, ALE,
spray pyrolysis, sol-gel) giving selected examples of problem-solving by thermal analysis. The techniques discussed are TG,
DTA/DSC, EGA and their combinations. High-temperature X-ray diffraction (HTXRD) is also a powerful tool for in situ studies
of thin films. The examples are taken from solar cell, superconductor and flat panel electroluminescent display technologies.
Authors:Y. Sawada, K. Omika, Y. Ito, F. Muta, and M. Momota
The formation process of a ceramic (indium oxide) thin film (thickness: approximately 20 nm to several microns) was investigated
by thermal analyses. Thermal changes of an organic precursor, indium(III) 2-ethylhexanoate, dip-coated on a glass substrate
was successfully detected by DSC in air. Exothermic phenomena were observed at marked lower temperatures for the thin films
than for the bulk material; thinner films had slightly lower peak temperatures. The reaction mechanism is discussed with reference
to mass spectra of the evolved gases.
Solid state reactions of sputter-deposited Nb/Al multilayer thin films, with periodicities in the range 10–333 nm, have been studied by differential scanning calorimetry. The first phase to form upon annealing the films in NbAl3. Constant-heating-rate calorimetric measurements show the presence of two peaks for the formation of this phase, while isothermal scans reveal that the first peak is associated with a nucleation and growth type transformation. The formation of NbAl3 is thus interpreted as a two-stage process of nucleation and growth to coalescence (first peak) followed by growth until the consumption of one or both reactants (second peak).
Authors:Elizabet Horváth, J. Kristóf, L. Vázquez-Gómez, Á. Rédey, and V. Vágvölgyi
The thermal evolution process of RuO2–IrO2–SnO2
mixed oxide thin films of varying noble metal contents has been investigated
under in situ conditions by thermogravimetry-mass spectrometry (TG-MS), infrared
emission spectroscopy (IR) and cyclic voltammetry (CV). The gel-like films
prepared from aqueous solutions of the precursor compounds RuOHCl3,
H2IrCl6 and Sn(OH)2(CH3COO)2–xClx on titanium metal support were heated in an atmosphere
containing 20% O2 and 80% Ar up to 600C. Chlorine
evolution takes place in a single step between 320 and 500C accompanied
with the decomposition of the acetate ligand. The decomposition of surface
species formed like carbonyls, carboxylates and carbonates occurs in two stages
between 200 and 500C. The temperature of chlorine evolution and that
of the final film formation increases with the increase of the iridium content
in the films. The anodic peak charge shows a maximum value at 18% iridium
Authors:E. Horváth, J. Kristóf, R. Frost, N. Heider, and V. Vágvölgyi
The formation mechanism of thermally prepared IrO2/SnO2 thin films has been investigated under in situ conditions by thermogravimetry combined with mass spectrometry (TG-MS) and
infrared emission spectroscopy (IRES). Mixtures of varying composition of the precursor salts (SnCl22H2O dissolved in ethanol and IrCl33H2O dissolved in isopropanol) were prepared onto titanium metal supports. Then the solvent was evaporated and the gel-like films
were heated in an atmosphere containing 20% O2 and 80% Ar to 600C. The thermogravimetric curves showed that the evolution of the oxide phases take place in several decomposition
stages and the final mixed oxide film is formed between 490 and 550C, depending on the noble metal content. Mass spectrometric
ion intensity curves revealed that below 200C crystallization water, residual solvent, and hydrogen-chloride (formed as a
result of an intramolecular hydrolysis) are liberated. The decomposition of surface species (surface carbonates, carbonyls
and carboxylates) formed via the interaction of the residual solvent with the precursor salts takes place up to 450C as evidenced
by emission Fourier transform infrared spectrometry.
Authors:A. Derafa, M.-C. Record, D. Mangelinck, R. Halimi, and A. Bouabellou
reactions between a metallic thinfilm and the silicon substrate. The investigation of the mechanism of phase formation is of great importance to understand the behavior of the materials and to optimize their properties. This study has already been performed