Multilayer Stack

Optical/antireflective Quantitative depth profiling of multilayered stacks coatings (Si02, Hf02, Ti02, Sn02, InSn Oj, etc.)... 

Fig. 4.62. Measured ellipsometric spectra of an a-Si/SiN multilayer stack (seven layers) on GaAs.

OLED devices are fabricated on a glass, plastic, metal, or ceramic substrate as a multilayer-stacked structure represented in Figure 3.1. 

Using this approach it is possible to prepare multi-layer stacks. First a layer under a first parameter set may lead to a first geometry, then underneath a second layer of tubes can be grown with a different parameter set. The underneath layer may be initiated at the bottom of a tube (to break through the bottom of a tube), or in the spaces between the tubes.Such multilayer stacks may be quite interesting in developing novel catalysts. 

Fig. 2.54 Neutron reflectivity profile for a symmetric PS-dPMMA diblock (Mw 30 kg moP1) as a function of incident wavevector (Russell 1990). The inset shows the scattering length density (b/V, the neutron scattering length per unit volume) profile normal to the film surface that was used to calculate the reflectivity profile shown as the solid line, This is typical of a block copolymer film containing a multilayer stack, with lamellae parallel to the surface.

The effect of GDM thickness on the capillary pressure curves has also been investigated.21 A pronounced shoulder was observed at low capillary pressures in the curves obtained for very thin samples. This feature was diminished for thicker samples and virtually non-existent in the capillary pressure curves obtained from multilayer stacks. The dependence of this feature on the sample surface area-to-volume ratio is a clear demonstration of finite-size effects.70... 

In Table 1, the consequences of requiring large areas for collection, the cost because of competition with currently available energy forms, materials specificity for performance, and durability (to reduce life-cycle costs) are summarized. These criteria dictate a multilayer stack collector design in which polycrystalline thin film(s) of the active material must be protected from a hostile terrestrial environment. 

Table 1. Cost, Performance, Durability, and Design Requirements in Multilayer Stacks for Collecting Solar Energy...

Polycrystalline Films/Coatings Materials Specific Multilayer Stacks Extensive Interfaces Interfacial Stability... 

Huskens et al. exploited host-guest interactions between dendritic guest molecules and CD-modified nanoparticles for the formation of organic/metal nanoparticle multilayers on a PDMS stamp (Fig. 13.15).88 The multilayer stacks were transferred to a complementary host surface, while no materials remained on the protruding areas of the PDMS stamp. These multilayers showed a well-defined thickness control of 2 nm per bilayer. 

Fig. 6.25 The multilayer stack actuator showing one strategy for electroding to avoid clamping stresses.

Figure 2. Asymmetric spin dependent scattering at CoFe/Cu and NiFe/Cu interfaces leads to the giant magnetoresistance effect observed in a (CoFe/Cu/NiFe/Cu)x2o multilayer stack (S. Cardoso, INESC MN).

Table P.6.c. Layer of finite thickness adding onto a multilayer stack...

P.6.c. Layer of finite thickness adding onto a multilayer stack P.6.C.I. Finite number of layers P.6.C.2. Limit of a large number of layers... 

Other nonfluorinated /3-diketonates such as Ba(dpm)2 have been used in conjunction with HF, in one case by sequential reaction using atomic layer deposition (ALD).311 This method also gave high-quality fluoride films and enabled deposition of multilayer stacks for optical filtering applications. 

In order to visualize the enzyme acting on the substrate, it was labeled with a water-soluble and highly photostable, fluorescent perylene diimide derivate (PDI) [41,42]. When labeled aPLAl ( 10 M) was added to a non-labeled POPC multilayer (stacks of bilayers), enzymes could be visualized as bright spots and areas of high enzyme localization could be clearly seen (Fig. 25.4). 

Figure 5. Calculated reflectance of a polysilicon multilayer stack with and without a surface oxide. (Reproduced with permission from Ref. M. Copyright 1979 Journal of the Optical Society of America.)...

Figure 8. Calculated 2 values for the p-Si layer in a multilayer stack, calculated as described in text. (Reproduced with permission from Ref. 25. Copyright 1984 American Physical Society.)...

Martin-Pahna RJ, Torres-Costa V, Arroyo-Hemandez M, Manso M, Perez-Rigueiro J, Martinez-Duart JM (2004) Porous silicon multilayer stacks for optical biosensing applications. Microelectron J 35 45 8... 

Swiss-roll cell This cell, shown in Figure 26.14, has been proposed for both electro-organic syntheses and wastewater treatment [29, 37, 38]. It is fabricated from a multilayer stack of the following sheet materials (a) a polymeric cathode spacer cloth or mesh, (b) a cathode mesh, (c) an ion-exchange membrane, (d) a polymeric anode spacer cloth or mesh, and (e) an anode mesh. These sheets are assembled in the sequence a-b-a-c-de-d-... 

In the previous sections, we summarized the current understanding of mechanical stresses in several individual thin films. One more significant fact has to be mentioned the stress behavior of thin film multilayer stacks is not simply the sum of the stresses of the individual layers. Instead, stacked thin films can pronouncedly affect each Ollier s properties [41]. Consequently, this influence has to be considered when selecting materials for an application. 

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