Polishing methods

It is necessary to modify the edge of the hole in various ways to reduce these stress concentrations. Some methods of modification are priming, plunging, and standard radiusing and polishing methods. In the Dry Low NOx Combustors, especially in the lean pre-mix chambers, pressure fluctuations can set up very high vibrations, which lead to major failures. 

Keywords optical telescopes, off axisaspheres, polishing methods... 

In the early days of silicon device manufacturing the need for surfaces with a low defect density led to the development of CP solutions. Defect etchants were developed at the same time in order to study the crystal quality for different crystal growth processes. The improvement of the growth methods and the introduction of chemo-mechanical polishing methods led to defect-free single crystals with optically flat surfaces of superior electronic properties. This reduced the interest in CP and defect delineation. 

For noble metals such as Pt, Ir, Rh, Ru and their alloys, a molten salt tip polishing method is found to be most effective. The recommended salt mixture is put into a crucible of Pt or more simply of Fe to about three quarters capacity. The salt mixture is melted with a gas burner and the tip polishing can then proceed as before. The crucible can be used as the counter electrode. Usually one finds the best result by keeping the salt just near its melting point, which is around 400 to 500 °C. 

For etching a very small specimen such as a very thin whisker, a drop of the polishing solution may be supported on a small wire loop, as shown in Fig. 3.5(d). The whisker is then dipped into the solution. All the electrochemical polishing may be done under a low power optical microscope. This tip polishing method has been used very successfully for polishing silicon and other semiconductor tips from thin whiskers, and also for polishing high temperature superconductor tips out of small, finely shaped chips.11... 

An embedding and polishing method can be used as an alternative to microtoming.48 In this case, a sample is placed in an uncured polymer resin, cured... 

B. J. Kestel, Polishing Methods for Metallic and Ceramic TEM Specimens, ANL-80-120, Argonne National Laboratory, Argonne, IL, 1981. 

Finally, gel filtration is most often considered an appropriate polishing method when the target antibody is already pure and the only impurities are foreign protein traces or fragments or aggregates that must be eliminated. In this context, separation processes for antibody purification are logical orthogonal combinations of methods. 

Kojima T. End point polishing apparatus and polishing method. US patent... 

Professor J.G. Park has produced a series of experiments to understand the effect of the different etching method and the different polishing method on film thickness variation after the CMP process. Figure 5.10 shows the height maps and line profiles of the six wafer types. Table 5.1 shows the parameters in this experiment of oxide CMP... 

To quantitatively analyze the impact of nanotopography on post-CMP oxide film thickness, we have introduced a spatial spectral method, and have used it to examine the effect of the pad type, removal depth, wafer manufacturing technique, and polishing method. However, the role of the slurry in controlling the impact of nanofopography on STI CMP is not yet clear. In this section, we discuss how the concentration of surfactant and abrasive size affect the impact of nanotopography. 

Wu, Y.-H. and L. Chang. 2010. Chemical polishing method of GaAs specimens for transmission electron microscopy. Micron 41 20-25. 

Application IBF technique has been developed for figuring high performance optics components, such as high precision optics used within the optical towers of lithography wafer steppers. Following other mechanical polishing methods, IBF is usually performed as the final step to remove the last surface errors. 

Fig. 3 Polishing methods and their corresponding mechanisms of material removal (Kasai et al. 1990)...

Thus, these three theories are all valid to a greater or lesser extent. None of them alone explains the phenomena observed in aU the numerous combinations of materials and polishing methods known so far. Today, it is known that the smoothing process during polishing occurs by a combination of these three hypotheses, in any possible proportion. 

Ota, K. Saito, A. Polishing agents suitable for fabrication of electronic, magnetic, or optical devices, polishing method, and fabrication of semiconductor device. Jpn. Kokai Tokkyo Koho JP 2001342454, 2001 Chem. Abstr. 2001,136, 41533. 

M. Desai, K. Moeggenborg, P. Carter, Sificon Carbide Polishing Method Utilizing Water-soluble Oxidizers, US7678700 B2, 2010. 

The following description illustrates various polish methods. 

Method (6) is a linear method. A pad mounted to a belt is moved linearly to polish a wafer that is placed with its face facing down. This is the reason why this method is called linear method. In view of the principle of polish, method (6) is the most rational method. However, since mounting a pad on the belt is difficult, this method is rarely used in these days. 

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. 

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