Delamination surface contamination

Applications of ISS to polymer analysis can provide some extremely useful and unique information that cannot be obtained by other means. This makes it extremely complementary to use ISS with other techniques, such as XPS and static SIMS. Some particularly important applications include the analysis of oxidation or degradation of polymers, adhesive failures, delaminations, silicone contamination, discolorations, and contamination by both organic or inorganic materials within the very outer layers of a sample. XPS and static SIMS are extremely comple-mentar when used in these studies, although these contaminants often are undetected by XPS and too complex because of interferences in SIMS. The concentration, and especially the thickness, of these thin surfiice layers has been found to have profound affects on adhesion. Besides problems in adhesion, ISS has proven very useful in studies related to printing operations, which are extremely sensitive to surface chemistry in the very outer layers. 

Coatings failure occurs by delamination (separating by layers) or by peeling (separating from the concrete). The latter happens most frequently when the adhesive bond with the concrete is lost. This type of failure occurs when coatings are applied without first removing the surface contaminants and laitance. Laitance, a film which can form on the surface of the concrete, is unreacted cement or cement which has risen to the surface of the concrete surface due to over-working fresh concrete. 

Of these failure mechanisms, the major ones associated with delamination include contaminated surfaces, inadequate adhesive coverage, stresses, voids, and moisture absorption. Many of these mechanisms are also responsible for other failure modes besides delamination. 

A general criterion for optimizing the metal CMP process is the controlled regulation of material removal, while simultaneously securing the processed surface from various CMP-related defects like scratches, dishing, delamination, erosion, contamination, line deformation, and galvanic corrosion (Baneijee and Rhoades, 2008 Choi and Korach, 2009). The considerations for improving material removal rates (MRRs) are mostiy relevant in the context of bulk Cu CMP, but are relatively less critical for the thin (<5 nm) diffusion barrier metal films. However, the requirement for defect control continues to remain a major issue in essentially all cases of metal CMP (Chandrasekaran et al., 2004). 

The samples are examined for any evidence of discoloration or surface contaminants, loss of surface resin, softness, delamination, interlaminar bhstering, or measles. The specimens having metal cladding also need to be examined for bhstering or delamination of the metal foil from the laminate material. 

Surface contamination and the cause of coating delamination could be effectively studied using the XPS technique. Sihcone adhesives when utilized with organic-film adhesion may undergo oxidative degradation. The degraded... 

This reversal of the sequence from TMS/HFE to HFE/TMS is the most important issue. The second major issue is the effect of the O2 plasma treatment on the fluorine-containing contaminants. The XPS analysis of an initial sample revealed virtually no silicon on the alloy surface beneath the lifted primer but did indicate a rather substantial fluorine presence. The appearance of a strong silicon signal on the interface side of the removed primer indicated that the entire plasma film had likely delaminated at the interface with the alloy. Analysis of additional samples confirmed that the entire film and primer system had delaminated from the alloy panels. 

It must be appreciated, that surfaces of Nb, Ta, V and Zr will be immediately reoxidized or otherwise contaminated upon re-exposure to air, albeit with thitmer layers (or in the limit a monolayer) relative to thick native films often encountered before abrasion. As a minimum, monolayer adsorption of contaminants is almost certainly assured in all but the best ultra-high vacuum (< 1 x torr or <1 X 10 Pa) or in systems which simultaneously sputter substrate surfaces with argon or other inert ion during catalyst deposition. Some interfacial impurities between the substrate and the catalyst layer are tolerated in practice. However, the state of the substrate surface immediately prior to catalyst deposition is critical for wetting and adherence of the catalyst layers and for prevention of delamination. Theoretical flux maxima will not be achieved if thick impurity layers at the cata-lyst/substrate interface hinder hydrogen diffusion. 

After RGA data are collected and analyzed, the package is delidded to examine the inside components, interconnections, materials, and surfaces. Because removing the lid is a destructive process, it should be done in a lid-down position with special equipment to vacuum off any debris. After delidding, the components, surfaces, and connections are optically examined followed by analytical testing such surface analysis for contaminants, especially chloride and sodium ions. Scanning acoustical microscopy (SAM) is very useful in detecting voids, cracks or delamination within the adhesive or at the adhesive bond line. An excellent overview of SAM and its variations may be found in Ardebili and Pecht. ... 

Reliability requirements may be classified as short term or long term. Thus, delamination may occur shortly after curing due to contaminated surfaces, improper... 

Certain performance losses of fuel cells during steady-state operation can be fully or partially recovered by stopping and then restarting the life test. These recoverable losses are associated to reversible phenomena, such as cathode catalyst surface oxidation, cell dehydration or incomplete water removal from the catalyst or diffusion layers [85]. Other changes are irreversible and lead to unrecoverable performance losses, such as the decrease in the ECSA of catalysts, cathode contamination with ruthenium, membrane degradation, and delamination of the catalyst layers. 

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