Conformal coverage

The Oriented Substituent Pharmacophore PRopErtY Space (OSPPREYS) approach, introduced by Martin and Hoeffel [6], is in software terms an extension of CCG s MOE package, written using SVL. The 3D oriented substituent pharmacophores are aimed towards better representation of diversity and similarity in combinatorial libraries in the 3D pharmacophore space. Combinatorial library design often operates only on substituents rather than on the final products as the complications related to the conformational coverage in the 3D space and the scaffold dependency limit the product-based approaches to smaller libraries. The 3D oriented substituent pharmacophores add two more points and the corresponding distances to each substituent pharmacophore which represent the relationship of the substituents in the product with only little additional information. The fingerprints permit the creation of property space by multidimensional scaling (MDS) and, since scaffold independent, can be stored separately and applied to different libraries [6],... 

Since CVD processes offer the possibility of conformal coverage of a severe terrain, this method of depositing aluminum has been considered. The most completely explored method employs an aluminum-organic compound, TIBAL,31 32 which is... 

Smellie, A., Kahn, S.D. and Teig, S., Analysis of conformational coverage. 2. Application of conformational models, J. Chem. Inf. Comput. Sci., 35, 295-304, 1995b. 

The potential benefits of CVD over other film deposition techniques are that CVD-derived films can be deposited under conditions that give conformal coverage, they can be deposited at low temperatures, there can be a high level of compositional control, thin layers can be deposited, the technique can be scaled to coat large areas uniformly, and there is also the possibility for area-selective deposition13 as a result of the chemical nature of this process. The details of CVD and related chemical deposition processes such as atomic layer epitaxy (ALE), organometallic vapor-phase epitaxy (OMVPE), and others have been described elsewhere.6... 

Rapid thermal CVD [191] used Conformal coverage over high-aspect-ratio... 

Remote plasma-enhanced CVD features is possible, i.e., improved control of interfacial properties Excellent conformal coverage of complex... 

Nickel plating is also extensively used for decorative and corrosion resistance applications. In most cases, it is electrolytically deposited. However, some applications can require high purity films or good conformal coverage that can be better performed by the CVD process. 

Although many reports are available on deposition performed at atmospheric pressure, low pressure operation is convenient in order to obtain satisfactory molar fractions of the precursor (of the order of 10 ) at relatively low (if possible less than 100°C) volatilization temperature, and also to achieve improved conformal coverage of the substrates. Only few investigations have been performed with varying deposition pressure."" It is worth noting that Ni(HL ) and NiCp have been decomposed in molecular beam epitaxy (MBE) conditions, but with a high carbon contamination for the latter." ... 

Nonvolatile FeRAM devices ntilize either PZT or SET derivatives. In low density memory FeRAM prodncts, CSD is frequently nsed as the deposition method. For high-density 4- or 32-Mbit FeRAM prototypes, CSD is still used by industry to fabricate ferroelectric PZT thin-fihn capacitors, although gas phase methods like MOCVD have advantages due to the potential for conformal coverage of small three-dimensional strnctures. 

These conditions will ensure that snfficient flnx is maintained into deep narrow volnmes, that shadowing and depletion effects dnring deposition are minimised and that a continnons conformal coverage is obtained. There are now several solution-phase deposition techniques available that show excellent surface coverage and a few gas-phase techniques that seem similarly suitable. 

Figure 6.9 EDX (energy-dispersive X-ray emission) Une scan across the cross-section of a nanoporous Xi02 film filled with CuInSi in an ILGAR process. ILGAR has the capability to provide conformal coverage even in very small volumes at large depths.

Only when a potential substantially larger than the deposition threshold is applied at the electrode will the deposition potential be attained on the TiOa surface or at the top of the TiOi layer, in which case a conformal coverage or top-surface deposition is obtained. Attempts to achieve void-filling coverage by electroless or purely chemical techniques have enjoyed only limited success. This is probably due to bottleneck effects in the transport path for the precursor solution as the deposition proceeds. 

Smellie A S, S D Kahn and S L Teig 1995a Analysis of Conformational Coverage 1. Validation and Estimation of Coverage. Journal of Chemical Information and Computer Sdence 35 285-294... 

Therefore, it can coat complex-shaped components and deposit coating with good conformal coverage... 

Therefore, it has difficulty coating complex-shaped components and producing conformal coverage Tend to use expensive sintered solid targets/sources Potential difficulties in large-area deposition and varying the composition or stoichiometry of the deposits... 

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