3D Configurations Could Lead to New Microchips

Researchers at MIT have found a new way of making complex three-dimensional structures using self-assembling polymer materials that form tiny wires and junctions. The work has the potential to usher in a new generation of microchips and other devices made up of submicroscopic features.

Transcript

00:00:05 Computer chips have been shrinking every year, and they require the complicated placement of trillions of tiny wires. This is getting difficult, though, as we are reaching limits to how small we can focus light, the traditional method of making small patterns such as wires. Our group is looking for new ways to pattern even smaller wires, that have the additional feature of being able to assemble spontaneously. We use a strategy involving diblock copolymers, which are large molecules made of two polymers

00:00:31 that are bound together and act as chemically distinct blocks. These blocks would rather not be neighbors, so they spontaneously separate, kind of like oil and water, but on a smaller scale. When they are put on a surface, they are able to form wire-like cylinder structures, but these cylinders usually form in a partially disordered pattern, making them unsuitable for most applications. Recently, we have discovered strategies for controlling their behavior in three dimensions. Here's how we do it:

00:00:57 We use barriers, which are made of silica-like materials, and which are used to order the cylinders as they form. We chemically alter the barriers to be repulsive to the self-assembled cylinders, and then introduce the diblock copolymers to the surface, allowing them to spontaneously self-assemble. Here we are looking at a simulation, but let's look at an actual experimental result, as seen with an electron microscope. This is what the final product looks like.

00:01:22 By precisely choosing the correct barrier positioning and size, we can control the self-assembly to create complicated 3D networks of cylindrical wires that may one day find their way into your next computer.