February 11, 2004 – A device created at MIT makes the most precise measurement device of all: the Nanoruler, with “ticks” a few hundred-billionths of a meter apart.
The Nanoruler achieves precision 10 to 1000 times that of conventional methods by combining two of them: mechanical ruling (dragging a sharp point across a surface) and interference lithography (two beams of interfering light producing “fringes” that can record grooves on a surface in a single exposure).
Thus, the tool is able to pattern parallel lines and spaces (gratings) across surfaces larger than 300mm in diameter, with a precision of less than one nanometer — “the equivalent of shooting a target the size of a nickel in Manhattan all the way from San Francisco,” quipped Carl Chen, part of the team at MIT’s Space Nanotechnology Laboratory in the Center for Space Research.
The tool’s precision is key to a number of applications, including semiconductors, but it’s also useful for creating gratings with tiny distances that can spread light into a spectrum for analysis. For example, NASA’s Chandra X-Ray Observatory is using a “high-energy transmission grating” developed at the MIT lab to spread x-rays into a spectrum, from which scientists can examine chemical compositions and temperatures of the source (e.g., the corona of a star).