Blending Plastics, Semiconductors To Form Flexible Chips

FAYETTEVILLE, Ark. - Disposable cell phones, flexible computer screens and wristwatch computers could be within technology’s grasp if organic plastics and electronic materials are combined to share a few traits. Plastic is cheap and flexible but slow in conducting electricity; while semiconductors are fast and "smart" in electronics but are heavy, brittle and expensive. So University of Arkansas physics professor Huaxiang Fu decided to use solid state theory to examine the properties of a combination of organic material and inorganic semiconductors. He and his colleague found that the hybrid will retain the superior electronic properties of semiconductors as well as its mechanical flexibility of organic material—and that it even has a few advantages over the pure semiconductor material.

Fu and his colleague Jing Li of Rutgers University report their findings in an upcoming issue of the Journal of Chemical Physics.

Researchers have synthesized organic-semiconductor hybrids, but their properties are not understood. Fu and Li’s calculations provide an overview of the needed understanding and knowledge to foster widespread use of hybrid composites. They looked at the properties of a single atomic layer of semiconductor material sandwiched between two atomic layers of organic polymers.

Knowing the probable properties of such materials allows researchers to make decisions about which materials to pursue for development into devices.

"This is a powerful example of what theory can do," Fu said.

Researchers thought that the atomic bonding in the organic material would affect the semiconductor’s properties, and it does but only slightly.

Fu and Li found that the hybrid material would conduct electricity nearly as well as pure semiconductor material. Further, they discovered that the hybrid material has a large energy absorption window, which means that it uses energy more efficiently than the pure semiconductor material.

With such a hybrid, researchers and manufacturers could use less of the expensive semiconductor material and still get the same or better electronic performance out of a device. Further, the material will be flexible.

"This will make devices much less expensive and easier to process," Fu said. "The market for these materials could be potentially huge."