Researchers at the University of Pennsylvania have created the thinnest plates that can be picked up and manipulated by hand, using corrugated plates of aluminum oxide. They are thousands of times thinner than a sheet of paper and hundreds of times thinner than household cling wrap, but they spring back to their original shape after being bent and twisted.Like cling wrap, comparably thin materials immediately curl up on themselves and get stuck in deformed shapes if they are not stretched on a frame or backed by another material. Graphene is even thinner, but it also curls up.