Thin films measurements

Figure 12. Arrhenius plot obtained from the thin-film measurement of Fig. 11 with additional data.

UV-1050 Thin Film Measurement System with StatTrax Version 7.0 User s Guide, Promet-rix (now KLA-Tencor, Santa Clara, CA) 1994. 

Klenkler RA, Xu G, Aziz H, Popovic ZD (2006) Charge-carrier mobility in an organic semiconductor thin film measured by photoinduced electroluminescence. Appl Phys Lett 88 242101... 

This paper described a number of the means for measuring the piezoelectric coefficients of bulk materials and thin films. In bulk materials, excellent references are available. Numerous means have been used over the years to measure the piezoelectric coefficients, which can be loosely grouped as charge-based and displacement-based. Accurate data can be obtained by many of the techniques, and agreement between measurement types is usually reasonable, provided that comparable excitation levels are utilized. In contrast, for thin films attached to substrates, the mechanical boundary conditions differ in charge and displacement based techniques. As a result, the direct and converse coefficients are not identical. In addition, perhaps because of the relative immaturity of the field, the numerous possible artifacts are not always accounted for, which can lead to erroneous results in thin film measurements. 

First, we briefly describe the theory for detecting polarization. Precise descriptions of the principle of the microscope have been reported elsewhere (see [3,4]). We also report the results of the imaging of the ferroelectric domains in single crystals and in thin films using the sndm. Especially in the pzt thin film measurement, we succeeded to obtain a domain image with a sub-nanometer resolution. 

Figure 16.18 Image of a PZT thin film measured by SNDM using rotating electric field.

Typical index-of-refraction spectra of Mg Zni- O thin films with wurtzite and rocksalt structure are plotted in Figs. 3.21a-d. Data for 0 < x < 1 originate from thin film measurements, those for x = 0 and x = 1 are... 

Ellipsometry can measure films from subnanometer to a few micrometers, depending on material properties and wavelength of the light source. It has been widely used for thin film measurement in various applications, from biology to semiconductor, and from solid/solid to solid/liquid interfaces [24,25]. Ellipsometer with electrochemical cell for in situ thin film analysis is available from J.A. Woollam Co., Inc. and has been used in the research on electrochemical deposition [26]. However, in situ measurement of anodic films is more challenging because the films are usually metal complexes with unknown optical properties and difficult to verify with other ex situ techniques. 

Figure 15 Dissociation rate of CO on Rh (grown at 90 and 300 K) and Ir (grown at 300 K) clusters supported on ultrathin alumina thin films, measured by XPS. The level of dissociation on extended Rh (111) and (210) surfaces is indicated. (From M. Frank and M. Baumer [183].)...

The optical propagation losses in the vacuum evaporated benzylic amide [2] catenane thin films, measured in planar waveguide configuration [47, 48] were found to be PL = 2.8 0.1 dB/cm at A = 1.32 (xm and PL = 4.0 0.1 dB/cm at A = 1.55 (xm, respectively. These values were determined by a two prism method [49]. As for polycrystalline thin films these value are significantly smaller han usually observed. It shows the ability of these molecules to form good optical quality thin films by using these technologically friendly technique. It shows also that the crystallites are very small, tens to a few hundreds of nanometers size. 

Optical thin film measuring instrument LEYBOLD OMS... 

R.J. King and S.P. Talim, comparison of thin film measurement by guided waves, ellipsometry and reflectometry , Optica Acta, Vol. 28, pp. 1107 -1123. 

They find a large photoexcitation signal at around 2.17 eV for a6T thin films measured at 4.2 K which is attributed to the excitation into the Bu state. 

The thickness of polymer transfer films to counterface surfaces can be measured with sensitivities into the angstrom range with the ellipsometer. The device can be arranged for in situ thin film measurements. 

K.P. Biju, M.K. Jain, Effect of polyethylene glycol additive in sol on the humidity sensing properties of a Ti02 thin film . Measurement Science Technology, 18, 2991-2996, (2007). 

Figure 14 Schematic of thin-film technique. The geometry of the oil film separating two water droplets (a) is recreated in a special holder in the thin-film measuring cell (b) (c) shows microscopic image at the beginning of the film-thinning process showing Newton interference rings.

The sensitivity can be a disadvantage when measurements of less ideal specimens are needed. A thin-film measurement can easily be disturbed by a small roughness of the top of a coating. A measurement of a substrate is easily disturbed by a small roughness or oxide/water layer of a few atoms. If these effects are not taken into account in the calculation, quite erroneous values can easily be obtained. 

Vohnsky, A. A., VeUa, J. B. Gerberich, W. W. Fracture toughness, adhesion and mechanical properties of low-k dielectric thin films measured by nanoindentation. Thin Solid Films 429, 201-210 (2003). 

M. (1999) Ferroelectric latigue of Pb(Zr, Ti)03 thin films measured in atmospheres of varying oxygen concentration. Appl. Phys. Lett., 74, 4032-4033. 

Figure 4.7 (A) UV-Vis near infrared spectra of P3TESH thin films measured under vacuum at different temperatures (B) variations of UV-Vis near infrared spectra of P3TESH thin film with time measured under vacuum and 40 °C. (Reprinted with permission from Chemistry of Materials, 9, 2750. Copyright (1997) American Chemical Society.)...

The technique, therefore, has found application in many diverse fields of thin-film measurements, and has the potential to be even more widely applied with the advancing capability, and declining cost, of the available instrumentation. 

III. STABILIZATION OF FOAM FILM A. Thin Film Measurements... 

Table I. Compositions of thin films measured by EELS and EDS...

Figure 6 shows the hardness of thin films measured by a nanoindenter. The film on the MgO substrate showed a higher hardness than that of the film on Si substrate in 5r = 0 and 10%. In the polycrystalline thin film on Si substrate, conventional result that hardness increases with increasing Si content was confirmed. The hardness was increased from 23 to 29 GPa. Furthermore, in the thin film on MgO substrate, hardness increases with increasing Si content. The hardness was increased from 29 to 36 GPa. This result could be supposed the effect of the obstruction of dislocation movement (solid solution hardening) for solubility of Si atoms in the CrN lattice. As the result, Cr-Si-N thin film on MgO substrate (5r = 10% Si content = 5.0 at.%) showed the highest hardness 36 GPa. 

The fluorescence excitation spectra are almost identical to the absorption spectra pointing at a constant fluorescence quantum yield over the whole range of the spectrum [181]. Dippel et al. find in low temperature measurements on a-6T an increase of the fluorescence quantum yield below 2.3 eV [257]. The group around Taliani (see, e.g. [25,237, 247, 263,264]) find a large photoexcitation signal at around 2.17 eV for a-6T thin films measured at 4.2K which is attributed to the excitation into the Bu state (compare Chapter 6 of this book [28]). 

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