We take thousands of scanning electron micrographs every year to document, characterize, and evaluate our surfaces. This collection contains our favorite images from the year, highlighting patterns from our ongoing research initiatives as well as the natural sources that help inspire us.

Developing patterns

A look at some patterns currently being developed

Hierarchical features in a diamond die

The inverse pattern in the mold

The structure replicated from the mold

400nm features replicated into a UV-cured polymer

5µm features replicated into a UV-cured polymer

Interwoven indents created in a nickel mold

Multi-scale features replicated into a UV-cured polymer

Replica Defects

As shown by the edge of this replica, the defects stand out in otherwise uniform patterns.

Areas where resist didn't fill, creating voids in the replica

A thin portion of resist resulting in a lack of feature fill (left) and a scratch in the resist creating loose polymer gumdrops (right)

Wrinkles and bubbles in the replicated polymer

Occasionally hard particles in the mold will damage the indenting tool, leading to missing features

Insects

These small organisms often possess nanopatterns that help them survive. Scientists study them to enhance their understanding of nanostructures.

The moth-eye effect gets its name from the hierarchical structures that can be found on the top of a moth's eye. These bio-inspired surfaces can be used to supress reflections on optics or increase transmission through solar panels.

Comparison of a textured moth's eye (left) and the smooth eye of a green june beetle (right).

Biocidal nanopillars seen on a cicada wing (top) and the scales from a moth's wing (bottom).

These images were taken by Lauren Micklow, Nicky Scott, Brenna Tryon, and Malcolm Shumel at the North Carolina State University Analytical Instrumentation Facility using an FEI Quanta 3D DualBeam SEM/FIB or a Helios 5 Hydra DualBeam SEM/pFIB.

The following is a collection of scanning electron micrographs taken as a part of ongoing research initiatives at SMS. They highlight patterns that are being developed for active projects and internal research as well as relevant patterns found in nature.

Molds

Metal molds created using our seamless nanopatterning process, nanocoining.

Ripples in the diamond die were replicated into the electroformed copper mold

Ripples in the diamond die were also replicated into the high phosphorous nickel mold

Material flow resulting from the nanocoining indenting process

Close up of material flow due to indenting

Square and rectangular grids

Closeup view of square grid

Linear gratings

Polymer Replicas

Following the fabrication of a master mold, the pattern can be transferred using nanofabrication techniques including thermal embossing and nanoimprint lithography.

Nanoimprint lithography (NIL) with a mold created with nanocoining at SMS was used to pattern this resist. Subsequent etching steps transferred this pattern into a metal layer to create a metal-mesh film for plasmonic IR absorbers.

Microlenses with a 2µm pitch

Linear grating with a 2µm pitch

Square grid with a 5µm pitch

Thermally embossed micro-pyramids

UV-cured polymer micro-pyramids

Micro-pyramids at the edge of a thermally embossed replica

Replica Flaws

Wrinkles and bubbles in replicas

A bubble between a UV-cured grid pattern and its polycarbonate backing

A pyramid pattern with a bubble

A photopolymer peeling off of the polycarbonate backing

A polymer ridge created from a crack in the mold

Interwoven Indents

Intentional tiling errors during the nanocoining process create patterns consisting of differently sized features.

A micropattern replicated into a photopolymer using a flexible shim and a batch NIL process

A pattern replicated using one of our seamless sleeves and a UV Roll-to-Roll NIL process

Nature

Many engineered nanopatterns find inspiration from nature. The biomimetic effects include hydrophobicity and structural color.

Intricate hierarchical patterns make lotus leaves self-cleaning and hydrophobic.

The microscopic tree-like structures give Morpho butterfly wings their vibrant blue color through a phenomenon known as structural color This image resembles a forest with tree-covered hills.

These images were taken by Lauren Micklow, Nicky Cates, and Brenna Tryon at the North Carolina State University Analytical Instrumentation Facility using an FEI Quanta 3D DualBeam SEM/FIB or a Helios 5 Hydra DualBeam SEM/pFIB.

SEM Gallery: The Art of Nanoscale Research

SEM Gallery: Images from Our Work at the Nanoscale