Princeton Researchers Create First Ever Completely 3D Printed Quantum Dot LEDs

It seems like everything is being 3D printed now-a-days. From human body parts, to electronics, to toys and gadgets for the kids, 3D printing is slowly becoming a mainstream technology. If you have followed the industry over the last year or so, you have likely heard about companies and researchers 3D printing optics, as well as LEDs.  Although an entire LED had not been 3D printed, researchers had been working on numerous possible ways of doing so.

As it turns out, this research may have finally paid off. A team led by Michael McAlpine at Princeton University, who last year made waves after 3D printing a bionic ear out of bovine cells and tiny particles of silver, have managed to 3D print an entire functioning quantum dot LED.

For those who are not aware, quantum dot LEDs have incredibly high color purity, as well as durability, efficiency, and flexibility which are unmatched in other more common display and lighting technologies. These LEDs are similar to, but not exactly the same as, LEDs found in common television screens and computer monitors.

The LEDs were created by mixing five different materials together in layers using a custom 3D printer which the team had spent the previous 6 months and $10,000-$20,000 creating. The first layer consists of a silver nanoparticle ring to act as a conductive base. Next comes two polymer layers followed by the quantum dots which consist of cadmium selenide nanoparticles which have been wrapped in a shell made of zinc sulfide. This is all topped off by the fifth and final layer which is made up of an eutentic gallium indium cathode and allows the electrons to leave the LED. All these materials have been 3D printed into one object within a single fabrication process, making this an incredible feat.  Although other researchers in the past may have claimed to have 3D printed LEDs, those  LEDs were not 100% printed like these created by McAlpine and his team.  The implications of this accomplishment could have a far reaching impact within dozens of industries.

“The conventional microelectronics industry is really good at making 2-D electronic gadgets,” says McAlpine. “With TVs and phones, the screen is flat. But what 3-D printing gives you is a third dimension, and that could be used for things that people haven’t imagined yet, like 3-D structures that could be used in the body.”

McAlpine believes that eventually if these types of 3D printers drop in price, people could one day be 3D printing their own do-it-yourself TVs or computer screens. Next up for McAlpine and his team are 3D printed transistors. They are looking to develop the technology which could one day allow for the printing of mini computers and functioning gadgets from the comfort of one’s home. Imagine the interesting applications one could come up with if a single printer could fabricate display technology along with transistors.  3D printed smartphones, anyone?

Let’s hear your thoughts on this work being down at Princeton, in the 3D Printed Quantum Dot LED forum thread on 3DPB.com.