MIT researchers have made a breakthrough that could pave the way for creating fully 3D-printed electronics without the need for semiconductors.
Their new study, published in Virtual and Physical Prototyping, demonstrates a method for 3D printing resettable fuses, key components of electronic devices that usually require semiconductors.
This development could bring electronics fabrication to homes, labs, and small businesses worldwide, potentially avoiding the costly semiconductor production process.
Semiconductors, such as silicon, are essential for most modern electronics because they can control the flow of electrical signals.
However, manufacturing these components requires specialized cleanroom facilities, which are only available in a few locations around the world.
During the COVID-19 pandemic, a shortage of semiconductor fabrication facilities led to widespread electronics shortages, affecting industries from consumer products to national defense.
The MIT team, led by Luis Fernando Velásquez-García, discovered a way to 3D print electronic components that can perform similar functions to semiconductor-based devices.
Their work could open the door to a future where 3D printing can be used to create fully functional electronics without relying on traditional semiconductor manufacturing.
The researchers didn’t initially set out to 3D print semiconductor-free devices.
Instead, their discovery came while working on a project to fabricate magnetic coils using extrusion printing, a method where the printer melts material and layers it to create an object.
They noticed that the polymer filament they were using, which was mixed with copper nanoparticles, showed an unusual property: when a large current passed through it, the material’s resistance spiked but returned to normal once the current stopped.
This resettable fuse behavior is something typically associated with semiconductors.
The team realized this phenomenon could be used to create transistors, the building blocks of logic gates that perform computation in electronic devices.
By adjusting the voltage fed into the printed material, they could switch the device on and off, much like a traditional silicon-based transistor.
The researchers tested other materials, but only the copper-doped polymer showed this behavior. They believe the copper nanoparticles spread out when heated by the current, causing the resistance spike, and return to their original configuration as the material cools.
While the 3D-printed switches don’t match the performance of silicon-based transistors, they could be used for basic tasks like turning a motor on and off.
Importantly, the devices remained functional after 4,000 switching cycles, showing their durability.
The process of 3D printing these devices is also more environmentally friendly than traditional semiconductor manufacturing, using biodegradable materials and less energy. The researchers aim to further improve their technique and explore other materials that could enable even more complex circuits.
Their ultimate goal is to 3D print fully functional electronics, such as motors or other components, using extrusion printing alone.
This could revolutionize the electronics industry, allowing devices to be created on-demand, anywhere in the world, without the need for complex manufacturing facilities.
Source: MIT.
