Patent Number: 055725627
Section: abstract

Fine, sub-micron line features and patterns are created in a sensitized layer on a semiconductor wafer by a source of X-ray radiation. The X-ray source emits very low wavelength radiation along a path towards a sensitized surface of a semiconductor wafer. An image mask substrate is disposed in the path of the radiation, and is provided with a patterned opaque material on a surface of a substrate thereof. The substrate is formed of beryllium, which is robust and has a thermal coefficient of expansion closely conforming to that of common image mask carriers. Further, a wide variety of opaqueing materials adhere well to the beryllium substrate, and the substrate is relatively insensitive to moisture. The image mask is spaced sufficiently close to the wafer that radiation passing through the mask forms a corresponding pattern in the surface of the wafer. For X-ray radiation, the opaqueing material is gold, tungsten, platinum, barium, lead, iridium, rhodium, or the like.