Flexible electronic products are expected to be mass produced at low cost
Traditional electronic products usually give us the impression of "hard",unable to be stretched and bent.Flexible electronics,with its flexible, scalable, ultra light,low power consumption,durable, portable,comfortable and other features,has become an important innovation and development trend in the electronic industry in the future.However,flexible electronic products will move from laboratory to large-scale market-oriented business in the future, "manufacturing cost and large-scale mass production"is still a key challenge.
With the development of new semiconductor material technology, especially the research and development of solvated organic and inorganic semiconductor materials,it is possible to use traditional printing technology to manufacture various electronic components.The biggest characteristic of solvated organic and inorganic semiconductor materials is：Independent of the conductor or semiconductor properties of the substrate material,it can be deposited on any material in the form of thin film by evaporation, spin coating or printing.
Researchers at North Carolina State University have developed a new technology that uses metal direct printed circuits to make flexible,stretchable electronic devices.This technology uses a variety of metals and substrates and is compatible with existing manufacturing systems using direct printing technology.
The technology adopts the existing electrostatic printing technology,which has been used in many manufacturing processes using functional inks. However, the team, led by Jingyan Dong, associate professor of industrial and systems engineering at North Carolina State University and co-author of the research paper,used a molten metal alloy with a melting point as low as 60 ℃ instead of functional inks.The researchers' technical demonstration used three different alloys,printed on four different substrates:glass,paper,and two stretchable polymers.Dong said that this is direct printing,no mask,no etching,no mold, making the process more simple and direct.
The researchers tested the elasticity of the circuit on a polymer substrate and found that the conductivity of the circuit remained unaffected after 1000 bends.Even if it is stretched to 70% of the tensile strain,the circuit can still conduct electricity stably.The researchers also found that even if the circuits were bent or stretched too much,they were able to self recover.Dong believes that because of the low melting point,you can simply heat the affected area to 70 degrees Celsius,and then the metal will flow back together to repair the damage.
The researchers demonstrated the function of the printing technology by making a high-density touch sensor and putting an array of 400 pixels into a square centimeter area.Dong said they had demonstrated the flexibility and functionality of the solution and were happy to work with the industry to implement the technology in the manufacture of wearable sensors or other electronic devices.
Dong says the solution reduces costs and provides an efficient way to make high-resolution circuits that can be integrated into commercial devices.