Pointing to similarities with graphene, the TUM team says silicon can form layers that are one atom thick. With unusual optoelectrical properties, the silicon nanosheets might find application in flexible displays, FETs and photodetectors.
“Silicon nanosheets are interesting because today’s IT builds on silicon and, unlike graphene, the basic material does not need to be exchanged,” said researcher Tobias Helbich. “However, the nanosheets are very delicate and disintegrate quickly when exposed to UV light, which has limited their application significantly.”
Helbich, in collaboration with Professor Bernhard Rieger, has embedded the silicon nanosheets into a polymer, protecting them from decay. At the same time, the nanosheets are protected against oxidation.
“What makes our nanocomposite special is that it combines the positive properties of both of its components,” Helbich continued. “The polymer matrix absorbs light in the UV domain, stabilises the nanosheets and gives the material the properties of the polymer. At the same time, the optoelectronic properties of the nanosheets are maintained.”
In what is said to be the first successful application of the nanocomposite, a research team created photodetector featuring polymer embedded silicon nanosheets on a silicon dioxide surface coated with gold contacts.