Electrode plating method

Apparatus and Procedure. Surface Isotherms. The technique for determining the n-A and AV-A curves of the lipid films has been described (6). Briefly, the Wilhelmy plate method was used to measure surface tension, from which the surface pressure was calculated (n = 7h2o—yfiim) The surface potential was measured by means of a radioactive (226Ra) air electrode and a saturated calomel electrode connected to a high impedance model 610 B Keithley electrometer (Keithley Instruments, Cleveland, Ohio). 

In heterogeneous systems, potential differences exist across the various phase boundaries. The surface film potential, AV, due to a monolayer is the change in the potential difference between the bulk substrate liquid and a probe placed above the liquid which results from the presence of the monolayer. Surface film potentials can be measured by air-electrode and vibrating-plate methods. 

In most cases the variation in surface stress has been determined indirectly by measuring the potential dependence of the strain (i.e., electrode deformation) and then obtaining the variation in stress from the appropriate form of Hookes law (-> bending beam or cantilever beam method, bending plate methods e.g., the measurement of the deformation of the electrode with the help of a —r Kosters laser interferometer). 

The contact angle of an electrolyte on a solid electrode changes when changing the potential. This effect was used by Morcos and Fischer, who measured the potential-dependent capillary rise of an electrolyte meniscus at the surface of a partially immersed metal plate 11551. The interfaeial energy at a solid elec-trode/solution interface can also be measured by the Wilhelmy plate method 1156,157],... 

Fig. 48. Surface potential measurements by the vibrating plate method. The oscillator (Osc.) and amplifier (Audio amp.) are commercial units which drive the electrode. The oscilloscope (Scope) and high gain, low noise amplifier (Amp.) are also standard commercial instruments.

Integrated electrodes are another option available for microchips in which the electrodes are fabricated into the microchip itself. Thin strips of metal, usually gold, are deposited on either the substrate containing the channels or the cover plate. Methods for this type of metal deposition and micropatterning are well established in the semiconductor industry. The interface connection then resembles a computer board in which the microchip plugs into a connector to make contact with the power supply. Although useful for disposable... 

The electrochemical plating method was used to fabricate IPMCs with different types of electrodes. The exact chemicals and reduction materials are shown in Table. 2.1. An Instron 5565 machine was used for the tensile testing (see Fig. 2.12 (a) for the setup). The fabricated IPMC samples were punched out using a dog-bone shaped punch mold. Its size followed ASTM 638 and 882, as shown in Fig. 2.12 (b). The tensile test was per-... 

Zirconia solid electrolyte sensor element is formed in thimble shape. Pt electrode layers as a thin film are adhered inside and outside of the sensor element by plating method. The portion of the sensor element is shown in Figure 3.1.1. The partially stabilized zirconia solid electrolyte sensor element is assumed as one wall. Along the border of the wall, oxygen in ionic form is transferred in a direction that reduces the difference of oxygen partial pressure between chamber A and chamber B. The series construction works as a battery due to the transfer. 

Method (10) is an ECMP (electrical chemical mechanical polish method). Electricity is applied to the film to be polished like di-plating of the plating electrode. This method was developed for polishing metal, especially Cu interconnect wire. For various reasons, this method has not become the mainstream. 

One of the earliest applications of the template method was to prepare ensanble miCTo-scopic (7, 18) and nanoscopic electrodes (116, 141). Such electrodes were prepared by electrochemically depositing noble metals within the pores of the commercially available polymeric filtration membranes. The fabrication of a microelectrode ensemble based on the electrochemical deposition of platinum into the pores of a track-etched microporous polycarbonate host membrane was first shown in 1987 by Charles Martin (7). The word ensemble was used to describe the final device because the elements in the device are not evenly spaced. The procedure is simple, and requires only routine and inexpensive electrochemical instrumentation. It was ultimately found that electroless plating allowed for more uniform metal deposition (116). Both plating methods are important for the fabrication of the array, and further considerations continue in the following. 

Polar polymer dielectric capacitors are miniaturized devices that are widely used in miniaturized circuits in modern electronics. In fabricating polar polymer dielectric capacitors, a physical vapor deposition process is used to coat polycarbonate foil with an A1 layer ( 0.5 pm) to act as the electrode plates. Melted metal is then deposited by an airbrush method on either a cylindrical or flattened roll to provide contacts for the terminal connections. By changing the dielectric thickness, the capacitor s voltage can be changed from 60 to 250 V. 

An established method of electrode plating on the ion exchange membrane for fulfilling the above criteria is chemical plating with platinum or gold electrodes. Oguro et al. firstly found the bending response of Nafion 117 chemically plated with platinum electrodes. However, a platinum electrode has a narrower electrochemical window and is mechanically... 

The standard method of electrode plating for the IPMC is chemical plating of gold or platinum as described in Chapter 5. Recently, several physical technologies such as printing or pressing using metal or metal oxide nanoparticles were reported [15, 16]. 

From the aforementioned materials, the noble metals (Pt, Au, or Pd) are usually a preferred choice for IPMC electrodes due to their high electrical conductivity and electrochemical stability and availability in cation complex form that can be effectively used with electroless plating method. 

In the first part of this section of starting experiments with IPMC actuator, basics of ionic polymer used for IPMC, electroplating method, and fabrication of IPMC device including deforming ionic polymer and patterning electrode are described. Since details of ionic polymers and plating methods are described in the preceding chapters, this part describes only a summary of them. 

In 1932, Shlecht and Ackermann invented the sintered plate. In those days, conventional plates involved a system in which the active materials were packed into a metal container called a pocket or tube. However, with the sintered-plate method, the active materials are placed inside a porous electrode formed of sintered nickel powder. In 1947, Neumann achieved a completely sealed stracture. This idea of protection against overcharge and overdischarge by proper capacity balance is illustrated in Figure 2.5. 

In his experiments with electricity, Faraday used twines, which were probably textile materials, to insulate successive coils of conducting wires woimd helically on dry wood or glass. Attempts to model the capacitor system with a textile or fibrous material in between the electrode plates have been made by few authors using analytical techniques involving the topology of the system. Some authors have tried to apply various empirical and semi-empirical formulas available for dielectric mixtures to the case of textile and fibrous materials. Some authors have used regression and extrapolation method to find out permittivity from measured capacitance. The following sub-sections briefly describe these attempts. 

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