WRITE, READ, ERASE, AGAIN AND AGAIN

Abstract

IN AN ADVANCE REMINISCENT OF the children's toy Etch A Sketch, researchers have developed a lithography method for preparing erasable nanometer-sized patterns. Similar to the play-thing with which kids sketch with aluminum powder then wipe the slate clean and start over again, the new technique provides a way to prepare nanoscale metal patterns that can be erased and redrawn repeatedly. Numerous procedures have been demonstrated in recent years for preparing nanoscale metal dots, wires, tubes, and other structures that may function as components of miniature electronic and optical devices. The processes are as varied as the structures themselves and rely on electrodeposition, electron-beam methods, scanning probe manipulations, and other distinct procedures. Despite the unique qualities of the fabrication methods, they tend to share an undesirable distinction: By and large, they're irreversible—meaning that the nanostructures cannot be created, removed, and recreated efficiently in a single pot. Now, ch...