Substrate microstructured

O. Zinger, G. Zhao, Z. Schwartz, J. Simpson, M. Wieland, D. Landolt, B. Boyan, Differential regulation of osteoblasts by substrate microstructural features. Biomaterials 26 (2005) 1837. 

Ballhom, R., and Heimann, R.B. (2007) Cold gas dynamic spraying (CGDS) of Ti02 (anatase) coatings on polymer substrates microstructural characterisation and photocatalytic efficiency. /. Photochem. Photobid. A, 187 (2-3), 285-292. 

Ischenko, V. et al. The effect of SiC substrate microstructure and impurities on the phase formation in carbide-derived carbon. Carbon 49, 1189-1198, 2011. 

Fig. 5. A 90° polished cross section of a production white titania enamel, with the microstructure showing the interface between steel and direct-on enamel as observed by reflected light micrography at 3500 x magnification using Nomarski Interface Contrast (oil immersion). A is a steel substrate B, complex interface phases including an iron—nickel alloy C, iron titanate crystals D, glassy matrix E, anatase, Ti02, crystals and F, quart2 particle.

As with chemical etches, developing optimum conversion coatings requires assessment of the microstructure of the steel. Correlations have been found between the microstructure of the substrate material and the nature of the phosphate films formed. Aloru et al. demonstrated that the type of phosphate crystal formed varies with the orientation of the underlying steel crystal lattice [154]. Fig. 32 illustrates the different phosphate crystal morphologies that formed on two heat-treated surfaces. The fine flake structure formed on the tempered martensite surface promotes adhesion more effectively than the knobby protrusions formed on the cold-rolled steel. 

Since multiple electrical and optical functionality must be combined in the fabrication of an OLED, many workers have turned to the techniques of molecular self-assembly in order to optimize the microstructure of the materials used. In turn, such approaches necessitate the incorporation of additional chemical functionality into the molecules. For example, the successive dipping of a substrate into solutions of polyanion and polycation leads to the deposition of poly-ionic bilayers [59, 60]. Since the precursor form of PPV is cationic, this is a very appealing way to tailor its properties. Anionic polymers that have been studied include sulfonatcd polystyrene [59] and sulfonatcd polyanilinc 159, 60]. Thermal conversion of the precursor PPV then results in an electroluminescent blended polymer film. 

When dealing with polymer blends or blockcopolymers, surface enrichment or microstructures may be observed as already discussed in Sect. 3.1. Quite similar effects may be expected for buried interfaces e.g. between polymer and substrate where one component may be preferentially enriched. In a system of PS, PVP and diblock copolymer PS-6-PVP it has been shown by FRS that the copolymer enrichment is strongly concentration dependent [158]. In a mixed film of PS(D) and end-functionalized PS on a silicon wafer the end-functionalized chains will be attached to the silicon interface and can be detected by NR [159],... 

The ECALE synthesis of V-VI (V Sb, Bi) compounds has been attempted in a few works. Antimony telluride, Sb2Te3, nanofilms with a homogeneous microstructure and an average size of about 20 nm were formed epitaxially on a Pt substrate [61]. The optical band gap of these films was blue-shifted in comparison with that of the bulk single-crystal Sb2Tc3 compound. 

Shen Q, Arae D, Toyoda T (2004) Photosensitization of nanostructured TiOa with CdSe quantum dots effects of microstructure and electron transport in HO2 substrates. J Photoch Photobio A 164 75-80... 

Unfortunately, although EBA cements have been subjected to a considerable amount of development, this work has not been matched by fundamental studies. Thus, the setting reactions, microstructures and molecular structures of these EBA cements are still largely unknown. In addition, the mechanism of adhesion to various substrates has yet to be explained. Such knowledge is a necessary basis for future developments. 

The role of the substrate temperature can be inferred from a plot of /J2 ev and R versus max at the three temperatures mentioned 200, 250, and 300°C (see Figure 49). At a substrate temperature of 200°C the refractive index is lower at every max than at a substrate temperature of 250°C. Further, the threshold at which dense material is obtained is observed to be a few electron volts higher than at 250°C. The refractive index at 300°C is high and independent of max-The microstructure parameter R as a function of max behaves similarly for material deposited at 200 and at 250°C. At 300°C the value of R is less than 0.1 and independent of max- It is noteworthy to show the relation between the internal stress and max as a function of temperature (Fig. 50). The stress is linearly... 

The deposition rate increases upon increasing the pressure. This is explained by noting that the impingement rate per unit area, r,, of molecules on the filament is linearly dependent on the pressure as r, = pj 2nksT, with the gas temperature. However, as the pressure becomes higher, the collisional mean free path of the silane becomes smaller, and the silane supply to the filaments becomes restricted. Moreover, the transport of deposition precursors to the substrate is restricted as well. The mean free path of silane was estimated to be 2.5 cm at a pressure of 0.02 mbar [531]. i.e.. the mean free path about equals the distance between filament and substrate. Indeed, a maximum in deposition rate is observed at this pressure. This corresponds to a value of pdk of 0.06 (cf. [530]). The microstructure parameter plotted as a function of pd has a minimum around Ms = 0.06 0.02 [530]. 

The strong dependence of the magnetic properties on the microstructure of the magnetic alloy implies that the substrate will also influence the magnetics, since the substrate will affect the nucleation and growth, the structure, and the PO of the material deposited on it. For electrochemically deposited films, most studies have examined underlayer effects as secondary to other aspects of magnetic thin films. A few relevant papers dealing primarily with the effects of underlayers can nevertheless be mentioned here. 

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