Electrode materials, sputtering

As the source of material (sputtering target) is a solid, a variety of electrode configurations can be used e.g., depositing material downward, upward or sideways. It is possible to electrically bias workpieces being coated. This can encourage a level of ion bombardment that can modify the surface and structure of a coating. 

Sputtered electrode material Gold Microsphere material Polybead carboxylate microspheres... 

The ATR element is coated with the electrode material to be investigated besides ITO other materials which can be sputtered or evaporated on the ATR crystal are applicable. 

The detected current is influenced considerably by any incomplete contact between sample and electrode, bubbles, grain boundary, and so on. So it is necessary to be careful in preparing the contact conditions for the sample and electrode interface in polymer systems. When the polymers are flexible films or soft paste, good contact is obtained by simply pressing. For hard or brittle polymer systems, it is difficult to get good contact by the pressing pressure. To improve the contact, it is necessary to melt the polymer material or to sputter electrode material on the... 

Because polymer formation and ablation are competitive and opposing processes, polymer-forming plasma has the least ablative effect however, ablation in such plasmas cannot be completely ruled out. Sputtering of metals used as the internal electrodes for plasma polymerization has been recognized as a contamination of plasma polymers. Under certain conditions, the sputtering of the electrode materials becomes significant and plays an important role in the engineering of interface as described in Chapter 9. 

In certain applications of plasma polymerization, the incorporation of electrode material, particularly in a controlled and designed manner, is extremely useful and becomes a great asset in LCVD. For instance, a thin layer of plasma polymer of methane with a tailored gradient of copper has been shown to improve the adhesion of the thin layer to a copper substrate as well as the adhesion of metal to a polymer film [3,4]. In general applications of LCVD, in which the metal contamination should be avoided, it is important to select the electrode material that has low sputtering yield. Titanium has been used successfully in such cases. 

EFFECT OF MAGNETIC FIELD ON THE SPUTTERING OF ELECTRODE MATERIALS... 

In contrast to argon plasma, in which the sputtering of metal from the electrode is the primary process, the deposition of polymeric materials via plasma polymerization predominantly takes place in methane plasma. In such a polymer-forming plasma, the sputter deposition of electrode materials is considered as a secondary process, and the extent of the sputtering of metal depends on the plasma polymerization conditions, the nature of the electrode material, and the magnetic field strength. 

Electroless plating on polymeric substrates activated by the sputter deposition of electrode material with simultaneous plasma polymerization is possible. 

To drive the volatile products directly from the electrode surface via a suitable inlet system into the vacuum chamber of the mass spectrometer, a plain gas-permeable membrane (e.g. PTFE or polyethylene) on which the electrode material is deposited by sputtering or vacuum evaporation is usually used. Alternatively, the material can be deposited onto a metal gauze that is fixed close to the gas-permeable membrane. DBMS cell constructions such as that shown in Big. 12.39 have been described that allow the use of massive electrodes, which are more easily available. 

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