Abstract: A method of fabricating a resist pattern for a gamma gate of high electron mobility transistors of gallium arsenide (GaAs) elements for high-speed data communication with low noise is disclosed. The method of fabricating the gamma gate according to the present invention includes the steps of forming a first resist pattern by coating a first resist on a GaAs substrate, and exposing, developing and baking the coated first resist, sequentially; and forming a second resist pattern by coating a second resist on the GaAs substrate and the first resist pattern. and exposing, developing and baking the coated second resist, sequentially. A portion of the GaAs substrate covered by the first and the second resist patterns defines a region that a footprint of the gamma gate is formed, and a portion of the GaAs substrate which is covered by the first resist pattern, but not covered by the second resist pattern defines a region that a head of the gamma gate is formed.

Abstract: The present invention provides an optical system for crystallization tool for producing an crystallized silicon thin film by using an excimer laser as a light source to crystallize an amorphous silicon thin film through a fine stripped pattern, including 1st to 10th lenses sequentially arranged along an optical axis from said excimer laser, wherein the 1st lens having both side made convex; the 2nd lens having one side made convex toward the light source and the other side concave; the 3rd lens having one side made convex toward the light source and the other side concave; the 4th lens having both side concave; the 5th lens having both side made convex; the 6th lens having one side concave toward the light source and the other side made convex; the 7th lens having one side made convex toward the light source and the other side concave; the 8th lens having both side made convex; the 9th lens having one side made convex toward the light source and the other side concave; and the 10th lens having both side made

Abstract: The present invention provides an optical system for crystallization tool for producing an crystallized silicon thin film by using an excimer laser as a light source to crystallize an amorphous silicon thin film through a fine stripped pattern, including 1st to 10th lenses sequentially arranged along an optical axis from said excimer laser, wherein the 1st lens having both side made convex; the 2nd lens having one side made convex toward the light source and the other side concave; the 3rd lens having one side made convex toward the light source and the other side concave; the 4th lens having both side concave; the 5th lens having both side made convex; the 6th lens having one side concave toward the light source and the other side made convex; the 7th lens having one side made convex toward the light source and the other side concave; the 8th lens having both side made convex; the 9th lens having one side made convex toward the light source and the other side concave; and the 10th lens having both side made

Abstract: Provided with an optical system which is applicable to an exposure apparatus used in the manufacture of semiconductors and includes a combination of a spherical mirror having a function of refraction and lenses for astigmation control, using a CaF.sub.2 lens as the last lens, thereby making it possible to use a light source operating at a short wavelength and a wide bandwidth, enhance the life of the optical system, and transfer the enlarge pattern of a mask onto the wafer for realizing fine line width.

Abstract: The present invention relates to an apparatus for forming fine patterns in semiconductor devices, display devices and micro-electro-mechanical systems and more particularly to an image projecting system using an optical component, which is made of birefringent material, in the lithography techniques. The lithography apparatus according to the present invention comprises an optical lens system in which an image of a photomask is transferred to an object by a light source, wherein said optical lens system comprises a plurality of isotropic optical unit and at least one birefringent optical unit, said birefringent optical unit including at least one of said birefringent optical components.

Abstract: A X-ray mask structure which reduces the distortion of the membrane, the X-ray mask structure including, a mask substrate having an opening in the central part thereof, a membrane formed on the mask substrate, the membrane having the chip site on which absorbers are arranged according to a desired pattern of a semiconductor device, and a support ring for supporting the mask substrate, which is defined by a plurality of fragments.