Researchers Uncover New Way To Etch Fine Lines

Researchers have come up with a new way to use a material that can be switched from transparent to opaque and back to etch extremely narrow lines on chips. The team has produced lines 36-nm wide and says they can place many such lines spaced a similar distance apart. While the approach is not new, the researchers employed a unique way of harnessing the property to create a mask with exceptionally fine lines of transparency. The researchers exposed a photochromic material, one that changes color and therefore its transparency when exposed to light of different wavelengths, to a pair of simultaneous light patterns, each of a different wavelength. When the bright lines at one wavelength coincide with the dark lines at the other wavelength, extremely narrow lines of clear material are formed, interspersed with the opaque material. The banded layer then serves as a mask through which the first wavelength illuminates a layer of material underneath. MASSACHUSETTS INSTITUTE OF TECHNOLOGY, Cambridge, MA. (617) 253-1000.