Floating carriers

Fig. 8. Wafer carrier with a floating carrier plate. Pneumatic pressure is applied through an inlet resulting in hydrostatic pressure directly against the wafer. There is not necessarily any independent retaining ring control.

Piggyba.ckFlota.tlon, This process has also been called carrier flotation. The principle is based on the flotation of fine particles adhering to others by mutual coagulation. Thus when one is floated the other, which is usually more difficult to float, is also collected. 

Fig. 17—Floating device for friction measurement [48]. 1—Carrier of strain gage 2—Strain gage 3—Beam 4—Plank 5—Steel ball 6—Oil cup 7—Mandril.

Tablets fast dissolving, lipid-carrier based, slow releasing, disintegrate without water, float in the stomach (gastric retentive), buccal... 

Overview of Unit Operations. To maximize the electron or hole (carrier) mobility and thus device speed, ICs are built in single-crystal substrates. Methods of bulk crystal growth are therefore needed. The most common of these methods are the Czochralski and float-zone techniques. The Czochralski technique is a crystal-pulling or melt-growth method, whereas the float-zone technique involves localized melting of a sintered bar of the material, followed by cooling and, thus, crystallization. 

Reddy, L. H., andMurthy, R. S. Floating dosage systems in drug delivery. Crit. Rev. Ther. Drug Carrier Syst. 19(6) 553—585, 2002. 

In carrier flotation, small-sized (several pm diameter) particles become attached to the surfaces of larger particles (perhaps 50 pm diameter, the carrier particles) [630]. The carrier particles attach to the air bubbles and the combined aggregates of small desired particles, carrier particles, and air bubbles float to form the froth. An example is the use of limestone particles as carriers in the flotation removal of fine iron and titanium oxide mineral impurities from kaolinite clays [630]. The use of a fatty acid collector makes the impurity oxide particles hydrophobic these then aggregate on the carrier particles. In a sense, the opposite of carrier flotation is slime coating, in which the flotation of coarse particles is decreased or prevented by coating their surfaces with fine hydrophilic particles (slimes). An example is the slime coating of fine fluorite particles onto galena particles [630],... 

Emulsion flotation is analogous to carrier flotation. Here, small-sized particles become attached to the surfaces of oil droplets (the carrier droplets). The carrier droplets attach to the air bubbles and the combined aggregates of small desired particles, carrier droplets, and air bubbles float to form the froth. An example is the emulsion flotation of submicrometre-sized diamond particles with isooctane. Emulsion flotation has also been applied to the flotation of minerals that are not readily wetted by water, such as graphite, sulfur, molybdenite, and coal [623]. Some oils used in emulsion flotation include mixed cresols (cresylic acid), pine oil, aliphatic alcohols, kerosene, fuel oil, and gas oil [623], A related use of a second, immiscible liquid to aid in particle separation is in agglomeration flocculation (see Section 5.6.4). 

When a high resolution mode is required, first switches 22 are closed so as to ground the enclosure regions 13 and second switches 23 are opened so as to float gate electrodes 15. Carriers generated in the vicinity of the enclosure regions are attracted and absorbed by the junction potential of the enclosure regions. Thus, no carriers flow into adjacent photodiodes. 

FIGURE 3.11 Schematic illustration of the cross section of different carrier models gimbal type (A), floating type (B and C), and actual example of a carrier (D). 

Carrier B [27] The wafer is supported by a membrane that is floated by a fixed carrier. Hydraulic pressure loaded on the membrane will control the polishing pressure (rate). The retainer ring is mounted in this carrier example, which can control the polishing pressure (rate) of the wafer edge portion. 

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