Electrode slurry processing

A better result in mixing may be obtained by first kneading the materials into a stiff paste and then adjusting the viscosity by adding the solvent so that it can be applied easily in the coating process. The electrode slurries (viscosity from 10,000 to 20,000 cps) are uniformly coated onto both sides of the current collector (aluminum foil for the positive and copper foil for the negative) of... 

Fig. 7. Fabrication process for MLC capacitors. Steps are (a) powder (b) slurry preparation (c) tape preparation (d) electroding (e) stacking (f) lamination (g) dicing (h) burnout and firing and (i) termination and lead attachment.

Two main operational variables that differentiate the flotation of finely dispersed coUoids and precipitates in water treatment from the flotation of minerals is the need for quiescent pulp conditions (low turbulence) and the need for very fine bubble sizes in the former. This is accompHshed by the use of electroflotation and dissolved air flotation instead of mechanically generated bubbles which is common in mineral flotation practice. Electroflotation is a technique where fine gas bubbles (hydrogen and oxygen) are generated in the pulp by the appHcation of electricity to electrodes. These very fine bubbles are more suited to the flotation of very fine particles encountered in water treatment. Its industrial usage is not widespread. Dissolved air flotation is similar to vacuum flotation. Air-saturated slurries are subjected to vacuum for the generation of bubbles. The process finds limited appHcation in water treatment and in paper pulp effluent purification. The need to mn it batchwise renders it less versatile. 

The creamy suspension is allowed to cool to room temperature, and the electrodes of a pH meter are inserted (Note 4). A solution of 20.5 g. (0.15 mole) of zinc chloride (Note 5) in 75 ml. of water is added dropwise with vigorous stirring over a period of 45 minutes, while the pH is maintained at 7 by the simultaneous dropwise addition of a 4A aqueous solution of sodium hydroxide (Note 6). The mixture is stirred for 1 hour and is then filtered with suction the solid product is dried under reduced pressure over phosphorus pentoxide. The dry material is slurried with 200 ml. of petroleum ether (b.p. 30-60°), and the solvent is decanted. This process is repeated five times, and the combined extract is evaporated at reduced pressure. The yield of almost pure -chlorophenyl isothiocyanate, obtained as a readily crystallizing oil with a pleasant anise-like odor, is 33-35 g. (65-68%), m.p. 44-45°. The product can be recrystallized from the minimum amount of ethanol at 50°. 

While there are a number of methods used for manufacturing the positive electrodes, the two most important processes are the sintering of silver powders and slurry pasting. The former procedure produces electrodes with superior mechanical properties. The silver mass which is formed by... 

Zinc electrodes for secondary silver-zinc batteries are made by one of three general methods the dry-powder process, the slurry-pasted process, or the electroformed process The active material used in any of the processes for the manufacture of electrodes is a finely divided zinc oxide powder, USP grade 12. 

The 64k, 80 pm x 80pm sized tilting mirrors are built on the top of a CMOS-based control ASIC. In order to reduce the topography of the underlying metallization/passivation structures, a 2.5pm-thick PECVD oxide film is first deposited on the ASIC. An ILD oxide CMP step based on Klebosol 30N50 colloidal silica slurry is used for planarization. In order to connect the ASIC with the deflection electrodes above (see Fig. 14.10), vias have to be etched into the planarized dielectric film. Then, a copper metal stack including a TaN barrier has to be deposited and a two-step Cu damascene CMP process has to be performed. As this process is equivalent to Cu damascene in microelectronics fabrication, standard Cu CMP slurries can be used. 

---