MASK FOR LASER MACHINING

• Main Authors: TANAKA MINORU, INOUE KENICHI, MIZOE YUKIO, SUGANO KENICHI, YAMAGUCHI MITSUHIKO
• Format: Patent
• Language: English
• Published: 06.07.1999
• Edition: 6
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

PROBLEM TO BE SOLVED: To improve machining precision of a micro-pattern and to reduce machining cost by providing a metallic film, which is to be patterned on a quartz plate glass, with a mulatilayer structure of plural metals of different properties and thereby improving laser resistance of a mask. SOLUTION: In performing high-precision microfabrication on a polyimide insulating film 11 on a ceramic substrate 12, a mask 4 to use is designed to have a metallic film of a three layered structure, in which a Cr film 8 with a large reflectance and a high melting point is formed as the initial layer on a quartz plate glass 5, in which a Cu film 9 with a large thermal conductivity is formed next on the initial layer, and in which a Cr film 10 is further formed as a barrier for preventing oxidation of the Cu film 9. Incidentally, it is desirable that the thickness of the Cr film 8 is 0.075 μm, Cu film 9 is 3 μm, and Cr film 10 is 0.075 μm which is for the prevention of oxidation of the Cu film 9. As a result, in carrying out laser beam machining with an energy density of 0.4-0.8 J/cm , the resistance can be fifteen times or higher compared with the mask of a single Cr film.