Full scale, microscopically resolved tomographies of sandstone and carbonate rocks augmented by experimental porosity and permeability values.

We report a dataset containing full-scale, 3D images of rock plugs augmented by petrophysical lab characterization data for application in digital rock and capillary network analysis. Specifically, we have acquired microscopically resolved tomography datasets of 18 cylindrical sandstone and carbonate rock samples having lengths of 25.4 mm and diameters of 9.5 mm. Based on the micro-tomography data, we have computed porosity-values for each imaged rock sample. For validating the computed porosity values with a complementary lab method, we have measured porosity for each rock sample by using standard petrophysical characterization techniques. Overall, the tomography-based porosity values agree with the measurement results obtained from the lab, with values ranging from 8% to 30%. In addition, we provide for each rock sample the experimental permeabilities, with values ranging from 0.4 mD to above 5D. This dataset will be essential for establishing, benchmarking, and referencing the relation between porosity and permeability of reservoir rock at pore scale.

Dielectrophoretic microbead sorting using modular electrode design and capillary-driven microfluidics.

Multiplexing assays using microbeads in microfluidics offers high flexibility and throughput, but requires the ability to sort particles based on their physical properties. In this paper, we present a continuous method for separating microbeads that is compact, modular and adaptive, employing an optimized electrode layout that alternates sorting and concentration of microbeads using dielectrophoresis and a nested design. By simulating the combined effects of the hydrodynamic drag and dielectrophoresis forces on polystyrene beads, the parameters of the electrode layout and voltage configuration are optimized for maximum separation based on particle size with a small number of slanted planar electrodes. Experimental verification confirms the efficient separation of 10 µm and 5 µm beads, with ~98% of all concentrated beads sorted in two separate streams and only ~2% of 5 µm beads leaking into the 10 µm bead stream. In addition, this method is implemented on capillary-driven microfluidic chips for maximum portability and ease of use.

Incorporating mask topography edge diffraction in photolithography simulations.

In deep ultraviolet lithography simulations, conventional application of Kirchhoff's boundary conditions on the mask surface provides the so-called "thin-mask" approximation of the object field. Current subwavelength lithographic operation, however, places a serious limitation on this approximation, which fails to account for the topographical, or "thick-mask," effects. In this paper, a new simulation model is proposed that is theoretically founded on the well-established physical theory of diffraction. This model relies on the key result that diffraction effects can be interpreted as an intrinsic edge property, and modeled with just two fixed parameters: width and transmission coefficient of a locally determined boundary layer applied to each chrome edge. The proposed model accurately accounts for thick-mask effects of the fields on the mask, greatly improving the accuracy of aerial image simulations in photolithography, while maintaining a reasonable computational cost.