Surface-energy pattern

Fig. 2 Droplet fusion devices, (a) Fusion based on electrocoalescence. Reproduced with permission from [40]. (b) Droplet fusion based on surface energy patterning. Reproduced with permission from [41]. (c) Fusion based on changing the concentration of surfactant in continuous phase. Reproduced with permission from [42]. (d) Pillars assisted droplet fusion. Reproduced with permission from [43]...

Figure 11.12 Morphological evolution in a 5 nm-thick film on a striped surface (/p = 3p,m = 2X). W=0.6, 1.2, 2.1, and 2.7 pm, respectively, for (a)-(d). The first image in this figure, as well as in the subsequent figures, represents the substrate surface energy pattern black and white represent the more-wettable...

Another method to improve printing resolution is to make use of predefined surface energy patterns on a substrate that forces material to remain in a preferred area on the surface. " These techniques rely on the use of expensive masks and conventional photolithography, which subsequendy increases the production costs. The resolution can be improved to a few micrometers. For example, Sirringhaus et al. obtained line... 

We did not extensively discuss the consequences of lateral interactions of surface species adsorbed in adsorption overlayers. They lead to changes in the effective activation energies mainly because of consequences to the interaction energies in coadsorbed pretransition states. At lower temperatures, it can also lead to surface overlayer pattern formation due to phase separation. Such effects cannot be captured by mean-field statistical methods such as the microkinetics approaches but require treatment by dynamic Monte Carlo techniques as discussed in [25]. 

Adsorbed layers, thin films of oxides, or other compounds present on the metal surface aggravate the pattern of deactivation of metastable atoms. The adsorption changes the surface energy structure. Besides, dense layers of adsorbate may hamper the approach of metastable atom sufficiently close to the metal to suppress thus the process of resonance ionization. An example can be work [130], in which a transition from a two- to one-electron mechanism during deactivation of He atoms is exemplified by the Co - Pd system (111). The experimental material on the interaction of metastable atoms with an adsorption-coated surface of... 

A number of researchers have used surface energy libraries to examine the self-assembly of block copolymer species in thin films. It is well known that substrate-block interactions can govern the orientation, wetting symmetry and even the pattern motif of self-assembled domains in block copolymer films [29]. A simple illustration of these effects in diblock copolymer films is shown schematically in Fig. 6. However, for most block copolymer systems the exact surface energy conditions needed to control these effects are unknown, and for many applications of self-assembly (e.g., nanolithography) such control is essential. 

Fig. 6 Illustration of surface energy effects on the self-assembly of thin films of volume symmetric diblock copolymer (a). Sections b and c show surface-parallel block domains orientation that occur when one block preferentially wets the substrate. Symmetric wetting (b) occurs when the substrate and free surface favor interactions with one block B, which is more hydrophobic. Asymmetric wetting (c) occurs when blocks A and B are favored by the substrate and free surface, respectively. For some systems, a neutral substrate surface energy, which favors neither block, results in a self-assembled domains oriented perpendicular to the film plane (d). Lo is the equilibrium length-scale of pattern formation in the diblock system...

Julthongpiput D, Zhang W, Douglas JF, Karim A, Fasolka MJ (2007) Pattern-directed to isotropic dewetting transition in polymer films on micropattemed surfaces with differential surface energy contrast. Soft Matter 3 613-618... 

The situation where the excess electric charge in the bulk of the semiconductor is zero has a particular importance because this can often be obtained experimentally. This state is called flat band situation and the respective electrode potential, flat band potential because in the absence of electric fields inside the semiconductor the position of the band edge energies runs flat from the interior to the surface 20>. This energy pattern at the semiconductor-electrolyte contact is shown in Fig. 10 for the flat band situation, i. e. an anodic and a cathodic... 

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