Cu structure

The symbol Cu, Cu Cuy, on the other hand, represents the cubic Cu structure as a stacking sequence of triangular layers viewed along the direction of the unit cell diagonal, which is perpendicular to the layers themselves. 

Relationships between the filling-up of the Cu structure and structures such as CsCl (see Fig. 3.31), Li3Bi and MnCu2Al have also been considered. 

Massive electrochemical attack known as galvanic corrosion [58,59] is the most severe form of copper corrosion. It can completely remove the copper from the structures (Figs. 17.25 and 17.26). It can occur when the wafers are exposed to a corrosive electrolyte for an extended period. It can also occur if the slurry does not contain enough or effective corrosion inhibitor. The source of such a galvanic potential on the patterned copper surface may be due to the fact that some copper structures connected to transistors have a different electrical potential than the rest of the wafer surface. Another possible cause of this type of galvanic potential is related to the barrier material induced metal metal battery effect. Most copper CMP slurries have been developed for Cu structures with Ta or TaN as a barrier material. In some cases, other metals may also be used in addition to the barrier metal. For example, a metal hard mask could contribute to the galvanic corrosion effects. It is also possible that some types of copper are more susceptible to corrosion that others. The grain... 

The magnetostrictive measurements were made on the same Ni plate. In the external magnetic fields more than 100 mT the change of deformations were not essential. However, the GMR effect appeared as usual in such fields. There was not any correlation between the magnetostrictive deformation and the stepwise change of current of the Ni-polymer-Cu structure. 

Shear superstructures of the anormal or multiple kind in the Al-subfamily of the Cu structure family are numerous. If the composition is Nj < 0.75, a shear variant of the Cu3Au type remains possible in the Al-subfamily when the shear vector which... 

The high rigidity is the key feature of the chiral spirobiindane ligands, which exhibited special advantages in many asymmetric reactions. One example is the Cu complex of chiral spiro bisoxazoline ligand (S, S,S)-23a (R=Ph). Zhu et al. [33] analyzed the X-ray structures of Cu(I)-(5, 5,5)-23a with various anions (PF, C10 , and BArp). All the complexes have an unexpected binuclear Cu structure, as shown... 

Recently it was shown that Raney copper has some activity for methanol synthesis [7,8], However, ZnO deposition on the surface is essential to a highly active copper surfaces [7], Previous investigations sought to improve the ZnO content in the leached Cu structures by changing the Zn content of the Al-Cu-Zn alloy [2-4], This paper describes a leaching/precipitation technique which produces ZnO promoted Raney Cu (RCD) and ZnO enriched Raney Cu-Zn (RCZD)... 

Determine values of the adsorption equilibrium constant for CO on Cu, the heat of adsorption, and the effective diffusivity of CO within the Cu structure under these conditions. You may assume that is very large. The carrier gas in all runs with CO was He, however, inert runs, as shown, were conducted with Ar. 

Several other research groups are actively contributing in this field of CcO model chemistry. Naruta et al. have reported tris(2-pyridylmethyl)amine Cu complex-linked iron meso-tetra-phenylporphyrin derivatives and well-characterized Fe—(O2)—Cu species that are similar to [( L)Fe -(0 )-Cu ]+ (Structure (7)). A CcO model developed by Casella and co-workers is a natural porphyrin derivative, in which a polybenziimidazole residue for the Cu coordination site is attached to the propionic acid side chain of the deuteroporphyrin. A new class of picket porphyrin, bearing covalently linked, axially placed tris(heterocycle) chelates for a copper ion, has been synthesized and characterized by Wilson and co-workers. ... 

The Cu/epoxy sample used for the above analysis was prepared in a novel way, tailored to get particularly flat and easy-to-scan surfaces. In this recent approach, electron beam lithography (EBL) and the lift-off technique were employed in order to produce well-defined Cu structures [29]. The sample preparation procedure is illustrated in Fig. 8.4 a. 

In the closely packed (1 X 1) Cu structure (Figure 4.33c) the copper atoms are obviously discharged and no co-adsorption of anions can be detected. The strain of an epitaxial layer... 

The experimental data are seen to differ from those calculated for a model with ideal Cu structure (discrepancy factor R = 0.14). The results obtained for a model with defect structure [Cuo.875Ho.i253Cuo.i25 with a copper atom in the center of hydrogen atom octant (i g. 2) are closer to the experimental date (R = 0.07). This structure seems to be stabilized by hydrogen atoms. The IR-spectrum of the sample [5] contains the absorption band in the region 2000-1900 cm-1 corresponding to the Me-H bond vibration [6]. 

Figure 4.26 Examples of defects that are observed to form over time after damascene Cu structures are created by CMP (Reprinted with permission from Canaperi et al., 2010).

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