We report the first simulations of nonsolvent-induced phase separation (NIPS) that predict membrane microstructures with graded asymmetric pore size distribution. In NIPS, a polymer solution film is immersed in nonsolvent bath, enriching nonsolvent, and leading to forms solid polymer-rich matrix polymer-poor pores. demonstrate how mass-transfer-induced spinodal decomposition, thermal fluctuations, glass-transition dynamics-implemented mobility contrast between phases-are essential formation...

We develop a multi-fluid model for ternary polymer solution using the Rayleighian formalism of Doi and Onuki, give an efficient pseudo-spectral method solving both diffusion momentum equations that result. Subsequently, we find numerical simulation is capable describing systems at micron length-scale easily reaches millisecond time-scales. In addition, characterize thermodynamics kinetics including (i) phase behavior, (ii) structure interfaces, (iii) mutual coefficients, (iv) bulk spinodal...

Motivated by the much discussed, yet unexplained, presence of macrovoids in polymer membranes, we explore impact Marangoni flows process nonsolvent induced phase separation. Such have been hypothesized to be important formation macrovoids, but little quantitative evidence has produced date. Using a recently developed multifluid field model, find that roll cells indicative solutal instability are manifest during solvent/nonsolvent exchange across stable interface. However, these weak and...

We use self-consistent field theory (SCFT) to study the self-assembly of diblock copolymers confined in cylindrical and non-cylindrical prepatterns. This situation arises contact holes -the hole shrink problem- where goal is produce a with reduced dimensions relative guiding prepattern. In this study, we focus on systems critical (CD) ranging from ~50nm ~100nm leading formation single PMMA domain middle holes. found that different morphologies arise process are strongly governed by...

We have investigated the directed self-assembly (DSA) of cylinder-forming block copolymers inside cylindrical guiding templates. To complement and corroborate our experimental study, we use field-theoretic simulations to examine fluctuations-induced variations in size position microdomain that forms middle hole. Our study goes beyond usual mean-field approximation self-consistent field theory (SCFT) incorporates effects thermal fluctuations description process using complex Langevin (CL)...

ABSTRACT We investigate the directed self‐assembly (DSA) of cylinder‐forming block copolymers inside extended guiding templates different sizes and shapes. focus in particular on that promote formation linear arrays two or three cylinders for contact hole multiplication. Using self‐consistent field theory (SCFT) simulations, we uncover existence windows two‐ three‐cylinder assess their stability relative to other defective morphologies present templates. From SCFT which DSA are lowest free...

We use self-consistent field theory to investigate the directed self-assembly of cylinder-forming block copolymers for purpose a graphoepitaxial pitch multiplication. focus in particular on conditions where two minor-block cylinders form inside confining rounded templates with neutral sidewalls and substrates. In addition perfect cylinders, various defective morphologies can also self-assemble guiding templates. According SCFT simulations, formation energy defects is typically above 20kT, or...

We have studied the self-assembly of PS-PMMA block copolymers by means SCFT simulations in elongated templates and established commensurability windows for formation single rows two three cylindrical VIAs. Our results indicate that VIAS with increasing CD form inside dimensions. The VIAs are symmetrically arranged template resulting hole-to-hole distances range from 24 nm to 34 lengths between 80 140 nm. emphasize present work assumed perfect templates; future studies will examine VIA...

Using phase-field simulations, we investigate the bulk coarsening dynamics of ternary polymer solutions undergoing a glass transition for two models phase separation: diffusion only and with hydrodynamics. The is incorporated in both by imposing mobility viscosity contrasts between polymer-rich polymer-poor phases evolving microstructure. For microstructures composed clusters matrix, significantly hinder coarsening, effectively leading to structural arrest. do not impede domain growth;...

We investigate the directed self-assembly (DSA) of cylinder-forming block copolymers inside cylindrical guiding templates. To complement and corroborate our experimental investigations, we use field-theoretic simulations to examine fluctuation-induced variations in size position microdomain that forms middle hole. Our study goes beyond usual mean-field approximation self-consistent field theory (SCFT) incorporates effects thermal fluctuations description process using complex Langevin (CL)...

To conclude, linear block copolymers are promising materials for DSA in cylindrical templates. However, contact multiplication extended and rounded templates, low defect formation energies correspondingly high levels anticipated AB diblocks. In contrast, A2B-type miktoarm show potential achieving the required defectivity threshold. Future work will include computational studies of with n > 2 such as A3B A4B, confinement rows many cylinders beyond two.

We use three-dimensional self-consistent field theory (SCFT) to study the self-assembly of cylinder forming diblock copolymers confined in elongated templates. This situation arises contact holes where goal is produce a hole with reduced dimensions as well narrowed pitch center-to-center distance cylinders. In this study, we focus on systems two minor-block cylinders form inside A defective bridge structure extensively studied work and evaluate defect various wall affinities such "all...

We use three-dimensional self-consistent field theory (SCFT) to study the directed self-assembly (DSA) of cylinder-forming block copolymers in a peanut-shaped (also called egg-box) prepattern. The design prepattern shape will target pitch reduction contact holes. idea is that DSA not only lead reduced critical dimensions relative template but also repair defects guiding prepatterns and produce defect-free blends homopolymers with various lengths volume fractions. Using SCFT simulations, we...

We use self-consistent field theory (SCFT) to study shape rectification in overlapped cylindrical and non-cylindrical prepatterns. Specifically, we examine the potential of directed self-assembly (DSA) block copolymers not only reduce critical dimensions relative template, but also repair defects guiding prepatterns produce defectfree contact holes. In our over a wide range prepattern dimensions, found that central minorblock domain arise with decreasing center-to-center distance prepattern....

Nonsolvent-induced phase separation (NIPS) is a complex but important phenomenon involved in the manufacture of fibers and other polymeric industrial products. We performed situ x-ray photon correlation spectroscopy (XPCS) measurements on cuprammonium cellulose solution immersed aqueous acetone to reveal structure dynamics NIPS process microscopic scale. A combination structural information from small angle scattering profiles dynamic XPCS analysis revealed that occurs via two steps:...

Using phase-field simulations, we investigate the bulk coarsening dynamics of ternary polymer solutions undergoing a glass transition for two models phase separation: diffusion-only and with hydrodynamics. The is incorporated in both by imposing mobility viscosity contrasts between polymer-rich polymer-poor phases evolving microstructure. For microstructures composed clusters matrix, significantly hinder coarsening, effectively leading to structural arrest. do not impede domain growth;...