Polishing tests

The wafer contour determines the area of contact between the wafer and the pad along with the abrasives. Thus, the amount of surface asperity interaction and the particle-wafer interaction also depends on the wafer contour. The fluid film that is in contact with the wafer surface is also dependent on the wafer contour. Thus, the pressure experienced by the wafer at different applied pressures and velocities changes with the shape of the surface. Scarfo et al. [20] conducted polishing tests on wafer samples with concave, convex, and intermediate surface contours and noted that the shape of the wafer affects the coefficient of friction. 

FIGURE 4.15 Pad condition during polishing tests with and without conditioning (from Ref. 24). 

Polished stone value (PSV) is the resistance of an aggregate to polishing, using the accelerated polishing test in BS 812. High values indicate increased resistance to polishing. 

The fused silica was an optical grade, pure silica made by flame hydrolysis. A polariscope examination through the polished test coupon faces and 6.3 mm thickness showed no residual strains. 

Current density can be increased without impairing the quaUty of the copper by polishing the cathode surface by brief periodic current reversals (PCR). Reversed current electrolysis, first developed for electroplating, was tested in 1952 for copper refining. Although good results were obtained, no suitable electrical equipment for current reversal was available. The thyristor-controUed siUcon rectifier, introduced in the 1960s, provided a means for... 

While detail may be found in the ASTM D-3330 or PSTC-1 and PSTC-2 standards, the peel test is typically carried out as follows The tape is conditioned at 23°C and 50% relative humidity for 1 day. Next, the tape is rolled down with a weighted standard roller onto a clean test substrate (usually polished 302 stainless steel), allowed to dwell for a specified time (usually 1 min), and then clamped with the testing fixture in the test machine and peeled at a specified rate. 

This test measures the ability of a tape to resist creep under applied load. The test is covered in ASTM D-3654 and PSTC-7. A specified area (typically 12.7 mmx 12.7 mm) of conditioned tape is rolled down with a specified pressure on the substrate of choice, such as polished 302 stainless steel. The panel is fixed in the vertical position or up to 2° tilted back so that there is no element of low angle peel in the test (Fig. lb). A weight (often 1000 g) is fixed to the end of the tape and the time to failure, i.e. complete detachment from the plate, is measured. Infrequently, the time required for the tape to creep a given distance is measured and reported. 

Metall-oxyd, n. metallic oxide, -oxydhydrat, n. metal (lie) hydroxide, -papier, n. metal (lie) paper, -poliermittel, n. metal polish, -probe, /, test for metal, assay, -putzmittel, n. metal polish, -rohr, n., -rbhre, /. metal tube oi-pipe, -rohrehett, n. (small) metal tube or pipe, -riickstand, m. metallic residue, -sa-fran, m. crocus of antimony, -salz, n. metallic salt. 

Vor-norm, /, tentative standard, -ozydation, /. previous oxidation, -polieren, n. roughpolishing, first polishing, -posten, m. out post, -praparation,/. previous or preliminary preparation or treatment, -probe, /. preliminary test, -produkt, n. initial (or primary) product crude product, specif, crude benzol intermediate, -produktkiihler, m. (Coal Tar) crude benzol condenser, -priifung, /. previous or preliminary examination, -pumpe, /. auxiliary pump (as for vacuum) (Brewing) circulator, wort pump. 

The micron ratings of a cartridge are intended to indicate the smallest particle that will be retained by the pores of the filter element. Often a rough-cut pre-filter is installed ahead of a final or polishing filter in order to increase the life of the final unit. Unfortunately, the method for determining the micron rating is not a universal standard between manufacturers. Thus, one manufacturer s 50 micron filter may not perform the same as another manufacturer s with the same rating number. The only reliable approach is to send the manufacturer an actual sample of the fluid and let him test it to select the filter to do your job, or actually test the unit in your plant s field application [37]. 

Amines remove the bulk of the H2S primary amines also remove the COj. Amine treating is not effective for removal of mercaptan. In addition, it cannot remove enough H2S to meet the copper strip corrosion test. For this reason, caustic treating is the final polishing step downstream of the amine units. Table 1-3 illustrates the chemistry of some of the important caustic reactions. 

Tests carried out for particular purposes may make use of other special means to measure the progress of corrosion. For example, changes in the reflectivity of polished surfaces have been used as a sensitive means of following changes in the very early stages of corrosion in laboratory studies. A similar technique has been applied on a practical scale in connection with the direct evaluation of the relative merits of different alloys as used for mirrors in searchlights exposed to corrosive natural atmospheres. 

Single Loop EPR Test The single loop method requires the sample to be polished to a 1 tm finish then passivated at -F200 mV (S.C.E.) for 2 min following which the potential is decreased at 1-67 mV s until the corrosion potential of approximately —4(X) mV (S.C.E.) is reached. The reactivation process results in the preferential breakdown of the passive film in the... 

Gravitational Methods GONELL AIR ELUTRIATOR. This is the prototype of all analytical separators with laminar air flow. It consists of a cylindrical brass tube (or a series of tubes) with a conical base. An air inlet is provided in this base on the axis of the tube. The sample of powder is placed in the inlet cone, and air is blown thru the largest tube until separation is deemed complete, or for specified periods of time. The residue is removed, weighed, and transferred to a smaller diameter tube, and the test is repeated. The tube should have polished internal surfaces and should be periodically tapped or vibrated to disturb settled powder... 

As part of the overall boiler plant operational management process, various items of water treatment equipment must be periodically checked, tested, back-washed, regenerated, or otherwise maintained. Such equipment may include filters, ion-exchange softeners and demineralizers, the RO plant, chemical feed tanks, and condensate polishers. 

The electrical double-layer structure and fractal geometry of a pc-Ag electrode have been tested by Se vasty an ov et al.272 They found that the geometrical roughness of electrochemically polished pc-Ag electrodes is not very high (/pz 1.5 to 1.25), but the dependence of Chtr curves on cej, as well as on/pz, is remarkable (C, =30 to 80 fi cm-2 if/pz =1.5 to 1.0). 

Khmelevaya and Damaskin621 have studied the electrical doublelayer structure at electrochemically polished pc-Sn. Effs0 = -0.63 V (SCE) (corrected by the asymmetrical type of electrolyte) the applicability of the GCSG theory has been tested and the values of /pz and C 0 have been reported. 

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