PURPOSE: To improve working accuracy by comprising a mask for machining with a base plate made of a material possible to essentially transmit a laser beam, and the pattern of a reflection film reflecting a laser beam arranged on this base material.
CONSTITUTION: A photoresist pattern is formed on the surface of a base plate 5 by a mask 5b for machining. Then the pattern of a Ne. Mg coating film is formed by spattering, and the photoresist is removed to make an AR (antireflection) coating film 11. All the laser beams are reflected by the AR coating film 11. For this Ne. Mg coating film, when another laser beam is used, a coating film with another material is used. All of a laser beam 8a butting the AR coating film 11 are reflected, and they are not absorbed at all by a mask 5b for working. Also, an object 6b to be worked is irradiated by the laser beam 8b in a part where there is no AR coating film 11.
KATAYAMA KAORU
WAI SHINICHI
MIYAUCHI TAKEOKI
HITACHI COMPUTER ELECTRONIC