Surface resistance measurement

Fig. 2. Measuring static charge, (a) Field voltage measurement (b) Faraday cage (c) surface resistivity measurement and (d) static decay test.

Surface Resistance Measurement of Static Dissipative Planar MaterialsD SW.W, EOS/ESD Association, 1991. 

Emersion has been shown to result in the retention of the double layer structure i.e, the structure including the outer Helmholtz layer. Thus, the electric double layer is characterised by the electrode potential, the surface charge on the metal and the chemical composition of the double layer itself. Surface resistivity measurements have shown that the surface charge is retained on emersion. In addition, the potential of the emersed electrode, , can be determined in the form of its work function, , since and represent the same quantity the electrochemical potential of the electrons in the metal. Figure 2.116 is from the work of Kotz et al. (1986) and shows the work function of a gold electrode emersed at various potentials from a perchloric acid solution the work function was determined from UVPES measurements. The linear plot, and the unit slope, are clear evidence that the potential drop across the double layer is retained before and after emersion. The chemical composition of the double layer can also be determined, using AES, and is consistent with the expected solvent and electrolyte. In practice, the double layer collapses unless (i) potentiostatic control is maintained up to the instant of emersion and (ii) no faradaic processes, such as 02 reduction, are allowed to occur after emersion. 

Figure 13-1. Electrode systems, (a) Showing fringing effect and surface conduction in volume resistivity measurement (b) showing volume conduction in surface resistivity measurement (c) electrodes, guard ring and circuit for volume resistivity measurement (d) electrodes, guard plate and circuit for surface resistivity measurement. (G = glavanometer or other current measuring device.)...

The method closely related to voltammetry is voltohmmetry, which is based on the fact that the lateral resistance of a thin metal film depends on the presence or absence of interacting species at its surface. Resistance measurements show a specific selectivity in the electrode potentials, and magnitude of resistance change depends linearly on analyte concentrations in solution from p.p.b. to p.p.m. range.58 This method is alternative for voltammetry, not only for heavy metals determinations, but also for nonelectroactive species that can be deposited or dissolved under defined potential of resistance. 

The electrodes and specimen for surface resistivity measurement may be in one of three forms. 

In looking for reasons for the enlarged residual surface resistance and the low Scrit of NbaSn, surface resistance measurements, R(T), were useful. These measurements indicated that about 10 parts of the surface contained precipitates with apparent TcS 3.6 K, evidence that these parts consist of the tin-rich phases NbeSns and NbSn2 [% Most likely they are located in corners between grains with those larger than 3 nm[= cLCNbaSn)] [ ] going normal. 

Surface resistance measurement of fabrics is mostly adapted from the ASTM D-257 standard [36]. Concentric ring probe is used (Fig. 28.16) in this method. 

Figure 28.16 Surface resistance measurement configuration for concentric ring probe [37].

Figure 28.17 The surface resistance measurement probe and the measurement setup.

W.A. Maryniak, T. Uehara, M.A. Noras, Surface Resistivity and Surface Resistance Measurements Using a Concentric Ring Prohe Technique in Trek Application Note, 1005, 2013. 

Surface resistivity measures the resistance of a material to moving or distributing a charge over its surface. The lower the surface resistivity value, the easier a material will redistribute an electrical charge over its entire surface area. Surface resistivity is discussed in Section 4.4 and the test procedure is described in ASTM D257. 

In Figure 8.13 the mesogen and compound types are specified. The results of surface resistance measurements with in situ polymerized films from these compounds are tabulated in Table 8.2. 

Insulation behavior is characterized by the resistivity that the base material can offer to the flow of an electric current. A distinction is drawn between volume resistivity (taking only the current flowing inside the plastic into account) and surface resistivity (measurement across electrodes touched to the surface) [8]. Conductivities can be introduced selectively by compounding electrically conductive fillers with the base material. 

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