Surface energy libraries

More recently, NIST researchers [13, 19] developed a device to more precisely generate surface energy libraries using OV-ozonolysis. Pictured in Fig. 5, this device achieves graded UV-ozonolysis through a computer-driven translation stage. 

Fig. 4 Water contact angle data (a) and surface energy data (b) from a surface energy library produced through the graded UV-ozonolysis of an ODS self-assembled monolayer on sihcon. (Reproduced with permission from [17])...

Fig. 5 Illustration of NIST Gradient UV-Ozone device for generating surface energy libraries on substrates functionalized with hydrophobic SAM species. The sample stage accelerates the specimen blue) beneath a slit-source of UV light. (Reproduced with permission from [12])...

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. 

The model contains a surface energy method for parameterizing winds and turbulence near the ground. Its chemical database library has physical properties (seven types, three temperature dependent) for 190 chemical compounds obtained from the DIPPR" database. Physical property data for any of the over 900 chemicals in DIPPR can be incorporated into the model, as needed. The model computes hazard zones and related health consequences. An option is provided to account for the accident frequency and chemical release probability from transportation of hazardous material containers. When coupled with preprocessed historical meteorology and population den.sitie.s, it provides quantitative risk estimates. The model is not capable of simulating dense-gas behavior. 

Hoeppener S, Wiesbrock F, Hoogenboom R, Thijs HML, Schubert US (2006) Morphologies of spin-coated films of a library of diblock copoly(2-oxazoline)s and their correlation to the corresponding surface energies. Macromol Rapid Commun 27 405 11... 

Fig. 7 2D thickness-surface energy gradient library for mapping the effects of these parameters on the self-assembly of PS-b-PMMA block copolymer thin films. See text for a fuU description. Lq is the equilibrium self-assembly period and h is the film thickness. Dashed white lines delineate the neutral surface energy region, which exhibits nanostructures oriented perpendicular to the substrate plane. (Derived from [18] with permission)... 

Fig. 8 Illustration of a gradient micropattem library. The central band of the library exhibits a micropattem that gradually changes the chemical differences between the striped domains and the matrix until the surface is chemically homogeneous. The bands on the top and bottom of the library are the calibration fields for static matrix and gradient respectively. 7 is surface energy...

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