Film thickness measurement

Fig. 4 —Measured film thickness—thick spacer layer [10],...

The model validation in mixed lubrication should be made under the conditions when asperity contacts coexist with lubrication. Choo et al. [45] measured film thickness on the surface distributed with artificial asperities. The experi-... 

Fig. 24—Measured film thickness perturbation for square features passing through the contact area under different sliding condition, taken from Felix [54]. (a) Slip=0 (b) Slip=1.0 and (c) Slip=-1.0.

Capacitance or conductance measurement This method is applied where the working fluid acts as a capacitive or conductive element in a circuit (Jones et al., 1981). Use of fiber optics sensors has been developed recently (Moujaes and Dougall, 1987, 1990). These methods are used to measure film thickness in annular flow. Further discussion appears in Section 3.3.4.4. For other regimes, the use of the electrical impedience imaging method has also been introduced (Lin et al., 1991). 

When the adsorption of collagen was allowed to occur overnight at 10°C, and the collagen solution was replaced by buffer still in the cold (10°C) using the dilution procedure, but the viscometer was subsequently transferred to a thermostat at 15°C, the results of Table I are obtained. Raising the temperature from 7.7°C to 15°C has roughly doubled the measured film thickness. 

In order to determine the appropriate development conditions, we examined dissolution characteristics for resist films in the aqueous alkaline developers by measuring film thickness as a function of development time. In Figure 7, dissolution characteristics for the new resist before and after exposure to KrF excimer laser are compared with those for the styrene resin matrix. 

Fig. 27 AFM sampling locations of the grafted region (1) and surface topological featiu-es of photograft-copolymerized surfaces as observed by AFM (2). AFM images of the gradient surface regions at 200 jjim (position e in 1) (2A) and 1100 jjim (position b in 1) (2B), which correspond to irradiation times of 13.5 and 6.75 min, respectively. Line scan spectra for selected regions corresponding to those in part 1 of the gradient film show the measured film thickness...

Ortega-Borges and Lincot [48] carried out a detailed kinetic study of CdS deposition from the standard ammonia (ammonium)/thiourea bath using a quartz crystal microbalance to measure film thickness. They measured a deposition rate with fractional values of reaction order... 

Portalski (P4), 1963 Theories of film flow and methods of measuring film thickness are reviewed. Film thicknesses on vertical plate (zero gas flow) reported for glycerol solutions, methanol, isopropanol, water, and aqueous solutions of surfactants. Results compared with values calculated by Nusselt, Kapitsa, and corrected Dukler and Bergelin treatments. 

Another instrument widely used to measure film thickness is a spectrophotometer that operates over the visible light (4800 to 8000 A) wavelength range. This instrument essentially quantifies the qualitative evaluation of film color mentioned earlier. A commercial instrument operating on this principle is shown in Figure 4. 

Fig. 3.9. Measured film thickness h vs. time for C10EO5 solution at CMC/3 (squares) ho - thickness...

A completely different behaviour exhibit NBF from NaDoS solutions. They do not change their thickness with pa and Cei alterations. However, their properties depend on the composition of the initial surfactant solution (see 0(Cei) and ta(Cei) dependences in Section 3.4.1.1). The thickness of NBF determined from h(Cei) dependence is approximately equal to the doubled thickness of the adsorption layer as assumed by Perrin [318]. This is confirmed by NBF obtained from other surfactants. It should be bom in mind that the interferometric technique employed to measure film thickness gives directly the optical difference in the path of the beams reflected by the two film surfaces. When the thickness is calculated from optical measurements a refractive coefficient, being a function of film structure, should be chosen (see Sections 2.1.3 and 3.4.1). 

Since there are no direct techniques for measuring film thickness in foams, Eq. (4.52) can be applied to calculate q> only for foams with films of equilibrium thickness. The latter can be determined by measuring the thickness of free foam films. 

Film thickness measurement Film thickness is measured after polishing, and the polishing data are then fed back to the next polishing. This is called an in-line monitoring. It is often used in ILD CMP. 

The measurement unit is composed of an optical head to measure film thickness and an R-0 stage to position the optical head below each test pattern on the wafer. To facilitate quick, convenient use, the measurement unit is located adjacent to the polishing table in the CMP equipment. Other components include a control unit, a fluid circulation unit, and an operation unit and they Eue all located neEU the CMP equipment. (Fig. 9)... 

This system employs a simultaneous film thickness measurement method, which incorporates a two-dimensional CCD camera detector , a variable wavelength light source, and an analyzer for the captured image data. With this configuration the system can, not only measure test pattern film thickness but also be used for a variety of visual wafer checks and film data inspections for Cu and other metal films during metal CMP. Moreover, we now have evidence that the system may even be able to handle moving wafers. With such potential, this system could evolve into a true In-Situ Monitor which measures film thickness inside the CMP unit itself with the same precision and accuracy. 

One of the most useful experimental methods to be applied to protein adsorption in recent years is the radiotracer technique (Mura-matsu, 1973). Proteins labeled with, 31I and 125I (Brash et al., 1974) and [14C]acetyl derivatives of proteins (Phillips et al., 1975) have been used as tracers. As well as measuring adsorption directly, this method has the great advantage that it can detect exchange between interface and bulk even when the total amount adsorbed does not vary. A technique that has been used to obtain independent measurements of the amount of protein adsorbed by measuring film thickness is ellipsometry (Trurnit, 1953). 

The aluminum coated plate used to measure film thickness was 0.5 cm wide and was placed on the substrate. In most experiments the spacing between electrodes was 1 cm. Other electrode spacings are noted in the results. Values of the cross section of styrene monomer and the volume of styrene polymers were calculated from the specific gravity of styrene. 

The quartz crystal microbalance (QCM) is a well-known tool to measure film thicknesses in the nanometer range [1-3]. It is difficult to imagine a device which is simpler than a quartz crystal resonator, and simphcity is one of the principal advantages of the QCM. A QCM is a disk of crystalline quartz. The disk displays acoustic resonances like any other three-dimensional body. As a resonator, it distinguishes itself from other resonators by a number of features ... 

A. Cameron and his co-workers developed an optical interferometric method of measuring film thickness and mapping film profiles, details of which are described in Chapter 6. The method is capable of resolving thickness to better than 100 nm and does not require empirical calibration. For reasons of technique, most of the published data are for a... 

Methods of measuring film thickness are treated in the following sections according to the basic principles on which they depend. Cases in which the thickness of the lubricant film can be determined by gross measurement of the gap between the bounding surfaces or by gross displacement of these surfaces will be excluded as too obvious to require discussion. 

Quartz resonant sensors measure film thickness by monitoring change in fundamental frequency of the quartz microbalance. The sensitivity is... 

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