New Thin Film Process Opens Possibilities for Making Flexible Photonic Devices

A simple filtration process helped Rice University researchers create flexible, wafer-scale films of highly aligned and closely packed carbon nanotubes. They have made inch-wide films of densely packed, chirality-enriched single-walled carbon nanotubes. In the right solution of nanotubes and under the right conditions, the tubes assemble themselves by the millions into long rows that are aligned better than once thought possible. The thin films offer possibilities for making flexible electronic and photonic devices, with a bendable computer chip rather than a brittle silicon one.

Transcript

00:00:00 [Music] carbon nanot tubes are their diameters are only on the order of one nanometer but their length can be millimeters cenm and individually they they have exhibited unusual properties Optical properties electronic magnetic properties they are extremely anisotropic but when you assemble them um typically

00:00:35 what you end up with is is a random network of of nanot types so therefore you you lose all the wonderful properties of individual carbon nanot types what we discovered here is is a new method it's a very simple method based on a vacuum filtration method to to make make huge wafer scale films okay centim Ines similar to silicon Wafers right in in which the nanot tubes are

00:01:04 globally aligned that's one of the uh discoveries we we made in in this work the the the second part is there's a there's a large family variety of carbon nanot tubes there are different species of carbon nanot some of them are metallic some of them are semiconducting and they have different properties depending on depending on the diameter okay diameter and the so-called um chyo

00:01:30 angle typically if you have an ensemble of carbon nanot tubes it's a mixture it's a mixture of metallic tubes and semiconducting tubes with different properties we were able to use one of these techniques uh before making films so so the result is we we now have a film okay in which the nanot tubes are aligned and also the the all the nanot tubes are

00:01:58 have the same diameter and same chyal angle okay so essentially we have a single Crystal like big object which consists of yeah single chirality carbon netives [Music]