Researchers from the Massachusetts Institute of Technology have come up with a new platform for growing the crystals needed for nano-light emitting diodes (nanoLEDs) in ultra-precise arrays — to within a margin of 50 nanometers.
"Studying nanoscale materials through high-throughput methods often requires that the materials are precisely localized and engineered at that scale," explains lead author Patricia Jastrzebska-Perfect of the importance of the team's work. "By providing that localized control, our technique can improve how researchers investigate and tune the properties of materials for diverse applications."
The research project focused on halide perovskites, known as a great material for solar cells and light-emitting diodes but typically built to a micron-scale on thin films. Creating nano-scale implementations opens up new potential, including the creation of ultra-compact crystal-based nanoLEDs — which is exactly what the team has built to prove its platform.
Eschewing traditional approaches the problem, including lithographic patterning, as being too difficult to control and integrate, the researchers developed an approach which allows the halide perovskite crystals to be grown on-site exactly where they need to be — to an error margin of 50 nanometers, a distance thousands of times smaller than the width of a human hair.
The process relies on a nanoscale template built with specially-shaped "wells." A solution with halide perovskite growth material is applied and pools in the wells, forming a tiny crystal in each. These crystals then form the heart of the nanoLEDs: apply electricity, and receive light.
The manufacturing process is scalable, the researchers claim, and could have potential for on-chip optical communication systems, microscopy, and in high-resolution display sytems, while the same approach could be used to produce other on-chip nanodevices.
The team's work has been published in the journal Nature Communications under open-access terms.