The researchers harvested single sheets of tungsten selenide (WSe2) using adhesive tape, a technique invented for the production of graphene. They used a support and dielectric layer of boron nitride on a base of silicon dioxide on silicon, to come up with the thinnest possible LED.
Wow, it seems like the current research in graphene has spawned at least one other possible application, using adhesive tape to create thin layers of homogeneous materials. This time it’s a liquid crystal material with possible applications in thin/flexible LCD displays. As the article says until now Organic LED (OLED) has been the material of choice for thin and even flexible displays. It’s also reassuring MIT was able to publish some similar work in the same edition of Nature magazine. Hopefully this will spur some other researchers to put some money and people on pushing this further.
With all early announcements like this in a fully vetted, edited science journal, we won’t see the products derived from this new technology very soon. However, hope spring eternal for me, and I know just like with OLED, eventually if this can be further researched and it’s found to be superior in cost/performance, it will compete in the market place. I will say the steps in fabrication the researchers used are pretty novel and show some amount of creativity to quickly produce a workable thin film without inordinately expensive fabrication equipment. I thinking about specifically the epitaxial electron beam devices folks have used for nano-material research. Like a 3D printer for atoms these devices are a must-have for many electronics engineering and materials researchers. And they are notoriously slow (just like 3D printers) and expensive for each finished job (also similar to 3D printers). The graphene approach to manufacturing devices for research started with making strands of graphite filaments by firing a laser at a highly purified block of carbon, until after so many shots, eventually you might get a shard of a graphene sheet showing up. Using adhesive tape to “shear” a very pure layer of graphite into a graphene sheet, that was the lightning bolt. Simple adhesive tape could get a sufficiently homogeneous and workable layer of graphene to do real work. I feel like there’s a similar approach or affinity at work here for the researchers who used the same technique to make their tungsten selenide thin films for their thin LED displays.
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