KABLab at Boston University
nanomanufacturing, mesoscale science, and hierarchical materials

Nanomanufacturing: develop processes that merge top-down patterning and bottom-up assembly
Top-down techniques excel at defining patterns with very high resolution. In contrast, nature extensively uses self-assembly to produce complex 3D materials with superlative properties.[53]  We seek to leverage the best of both of these approaches by directing bottom-up assembly using top-down control. We draw from a diverse spectrum of top-down approaches including scanning probe lithography, two-photon polymerization, photolithography, and electron beam lithography. Ultimately, our goal is to develop new approaches for nanomanfucturing by fundamentally understanding each process and developing transformative advances in their capabilities. A major push has been scanning probe lithography. For instance, we found that it is possible to measure the amount of ink on a scanning probe in real time and that this feedback can lead to the observation of writing individual nanoscale features.[51] Additionally we discovered that massive arrays of cantilever-free pens can be actuated using light, allowing for very general and high throughput nanopatterning.[54]  

Mesoscopic science: investigate how mesoscopic order affects the behavior of soft materials
When do a collection of molecules become a material? This question underlies the field of mesoscale science that is focused on the grey area between individual molecules and bulk materials. Such size-dependent phenomena is well known in the solid state, but less explored in the field of soft materials, in part because it is hard to study the properties of soft materials at the nanoscale. For example, we recently provided a framework for unambiguously determining the mechanical properties of thin polymer films which allowed us to verify that amorphous polymers become softer as they are confined.[50]

Hierarchical materials: design and realize materials and devices that leverage hierarchical structure
Nature uses structures with many length scales to form extraordinary materials using otherwise mundane constituents. We take inspiration from this and seek to identify the most effective ways to combine materials in three dimensional arrangements to produce useful emergent properties. In addition to exploring new ways of designing hierarchical structural materials, we study systems in which miniscule interactions work constructively to make macroscopic effects. Recently, we have explored liquid marbles, or macroscopic liquid drops that are rendered non-wetting by virtue of being coated with hydrophobic microparticles. These are fascinating examples of hierarchical structures as we found that while the elastic behavior does not depend on the coating, the failure mechanics are dependent on the interactions between particles.[52

Assistant Professor Keith A. Brown leads the interdisciplinary KABLab. He holds appointments in Mechanical EngineeringMaterials Science & Engineering, and Physics

We gratefully acknowledge support from: 

The Air Force Office of Scientific Research 
Multidisciplinary University Research Initiative (MURI) FA9550-1-16-1-0150

The National Science Foundation
Nanomanufacturing (NM) CMMI-1661412

The American Chemical Society Petroleum Research Fund
Doctoral New Investigator 57452-DNI9

The Gordon and Betty Moore Foundation

The Moorman-Simon Interdisciplinary Career Development Professorship

The Boston University College of Engineering
Dean's Catalyst Award

The Boston University Nanotechnology Innovation Center (BUnano)

The Boston University Division of Materials Science & Engineering
MSE Innovation Award