Self-Assembled One-Dimensional Nanostructure Arrays

Abstract

A range of proposed devices relies on the electronic, optical or magnetic properties of one-dimensional (1D) chains of nanoparticles. Here, well-controlled 1D arrays have been formed by templating a spherical-morphology block copolymer within a narrow groove. Significantly, the domains are distorted into ellipses with aspect ratio and major axis orientation controlled by the groove width. This technique gives unprecedented control over the period, particle size, aspect ratio, and orientation of nanoparticles in 1D arrays, making it valuable for creating self-assembled masks for the fabrication of novel devices.

Local Defectivity Control of 2D Self‐Assembled Block Copolymer Patterns

“…Our method for forming defect-free local areas in symmetric PS-b-PMMA thin film striped patterns involves engineering surface geometries with appropriate surface and interfacial tensions, defining confined volumes commensurate to intrinsic polymer dimensions for free-energy minimization, - and promoting polymer shear flow along preferred directions. The technique augments previously demonstrated graphoepitaxy methods for inducing orientational order in confined thin films of spherical, [12][13][14] cylindrical, [15,16] and lamellar [17] block copolymers. For self-assembled spherical and cylindrical phase morphologies (i.e., minority-block spheres or cylinders embedded in a matrix of the majority block), graphoepitaxy works best when the polymer minority block preferentially wets the substrate material (both trench bottoms and sidewalls) to form a brush monolayer on all surfaces.…”

Self-assembled block copolymers: Bulk to thin film

“…389 Later, Ross and Thomas and coworkers studied the packing of a multiple layer of poly(ferrocenyl dimethyl silane) (PFS) spherical microdomains in PS-b-PFS by varying the width of the trough (W). [390][391][392][393] When W = nd (in which n is the integer, and d is the distance between the rows of spherical domains in a closed-packed two dimensional array; thus d = p/2 in which p is the center-to-center spacing of spheres), the n layers of spherical microdomains with a diameter of D o (in which D o is the diameter of PFS in the bulk PS-b-PFS) are observed. However, for (n -1/2)d < W < nd, the total layers of spherical microdomains are n, but the diameters of these spheres are smaller than D o .…”

Block Copolymer Lithography for Magnetic Device Fabrication

“…9A). 113 Figure 9B shows that the diameter of the domains, measured perpendicular to the channel, increases with the groove width, while the diameter parallel to the channel remains constant. Figure 9C shows the aspect ratio of the domains vs W/d 0 also increases with template width.…”

“…Ordered spherical, cylindrical and lamellar microdomains have been observed in narrow templates regardless of the incommensurability. To drive the inplane long-range order of spherical and cylindrical microdomains in thin films, lithographically-defined grooved substrates, 32,65,[101][102][103][104][105][106][107][108][109][110][111][112][113][114][115] soft PDMS stamps and hard imprint molds 116,117 have been used as templates to impose lateral confinement. In-plane cylinders typically line up along the edges of the templates, while spheres and perpendicularly-oriented cylinders align their most densely-packed rows parallel to the edges.…”