A team from the Massachusetts Institute of Technology has made an important breakthrough in the field of electronic manufacturing: they used full 3D printing technology to produce active electronic device devices that do not require semiconductor materials.
This groundbreaking research, published in the latest issue of the journal Virtual and Physical Prototyping, opens up new avenues for future electronics manufacturing.
The team used ordinary 3D printers and low-cost, biodegradable materials to print these semiconductor-free devices. Although these devices are not yet powerful enough to match conventional semiconductor transistors, they can perform some basic control tasks, such as regulating the speed of electric motors. This new technology uses less energy and produces less waste, not only lowering production costs but also reducing environmental impact.
During the experiment, the team discovered that polymer filaments doped with copper nanoparticles have a special phenomenon: when a large current is passed through, the material will show a significant increase in resistance; and once the power supply is stopped, its resistance quickly returns to the initial state. This property allows the material to be used as a switching component, similar to transistors in semiconductors. The team tried a variety of polymer filaments with different dopings, including carbon, carbon nanotubes and graphene, but only filaments containing copper nanoparticles demonstrated self-resetting capabilities.
Based on this phenomenon, the team believes that the thermal effect caused by the current may cause the copper particles to diffuse, increasing the resistance; and after cooling, the copper particles regroup and the resistance decreases. In addition, the process of the polymer matrix changing from crystalline to amorphous and back may also contribute to the change in resistance.
Using this principle, the team developed a new logic gate composed of filaments made of copper-doped polymers, which can control the change in resistance by adjusting the input voltage.
In addition, adding other functional particles to the polymer filaments can also achieve more complex and diverse applications. This achievement shows the possibility of small enterprises independently producing simple smart hardware in the future.
Transistors can realize on-off control of output current and realize multiple logic gate functions through different circuit configurations. This time, the research team successfully used full 3D printing technology to produce active electronic device components that do not require semiconductor materials. Although the performance is not enough to match that of transistors, polymer filaments doped with copper nanoparticles already have basic control functions, and this material is low in cost and has little waste, and may become a "substitute" for transistors.