UNC Chapel Hill and NC State are part of a larger university research group that has received $7.5 million in funding from the U.S. Department of Defense to develop organic semiconductors for the next generation of electronics over a five-year period.
UNC’s Department of Chemistry Chair Wei You will work with NC State’s Herald Ade, Aram Amassian and Franky So. The two Triangle universities will work alongisde the University of Washington’s David Ginger and Xiaosong Li and Iowa State’s Baskar Ganapathysubramanian.
The project—titled “Next Generation Molecular Dopants for Organic Electronics: From Fundamentals to New Device Concepts”—could help to improve the portable power, energy efficiency and durability of screens and information display devices used in the cockpit and the field.
The research team is specifically looking to advance the technology of a class of semiconductors called organic semiconductors. Semiconductors generally are made from silicon and serve as the brain of modern electronics, powering smartphones, radios, televisions, computers and more. Organic semiconductors may bring the potential to change lives and the way the military operates.
“This is the one of the outstanding issues that people have paid much more attention to lately,” said UNC’s You, “but nobody can solve the problem yet because this is becoming a bottleneck from the Department of Defense standpoint for such devices to be successful.”
The Department of Defense has a vested interest in seeing if soldiers can carry lightweight organic plastic solar cells to charge their devices instead of hauling around pounds of traditional batteries, You said.
“If we imagine that the modern soldier is possibly carrying maybe 50 pounds of stuff on his or her body when they go to the battlefield…all of them will need electricity,” You said. “What that means is that when they are on the mission in the battlefield, they possibly need to carry 20 pounds of battery with them.”
Semiconductors are critical components of modern technologies, said NC State’s Amassian, as they are the hardware that provide the brains and computational power to all machines.
“As we embed semiconductors and machines in our daily lives, in our clothes, on our skin and even in medicine, it is important that we develop soft and printable semiconductors that exhibit properties and compatibility with biological systems,” Amassian said. “That is why advancement in next-generation semiconductors is so important to our society.”
A molecular dopant is a molecule which, when added to other materials, adds or withdraws one or more charges (electrons), and in doing so “tunes” the electronic and optical properties of matter—which is of vital importance for semiconductors. Amassian said that understanding how doping happens in molecular systems is currently far behind that of conventional semiconductors, a deficit that this research hopes to help bridge so that molecular doping may be widely used in printed electronics to create exquisitely controlled materials.
At NC State, one of the focal points will be to leverage robotic experimentation platforms created in the laboratory in conjunction with data science and artificial intelligence to help extract features from large datasets and guide the design of next-generation dopants and materials, Amassian said.
“This means a lot to my students and me as we have labored for years to design and build these new research platforms,” Amassian said, “and we are honored that our vision has resonated—as evidenced by this award.”
UNC’s You said that achieving new advances in organic semiconductors requires collaboration and new thinking, and the universities’ research will ultimately transform the field by providing in-depth knowledge of the doping mechanism and its effect on charge carrier density and mobility.
By utilizing machine learning and robotics, the team is also predicting where semiconductor enhancements should go next.
“The other unique aspect of our program is that we’re not just talking about doing trial and error,” You said. “We actually apply the high throughput robotic platform to create a lot of data, and that will be screened by using machine learning that will help us to act on what to do next.”