Metal plate processing method, lead frame processing method, lead frame, semiconductor device manufacturing method, and semiconductor device

摘要

An object of the present invention is to, in methods of processing metal plates and lead frames, enable workpieces to be finely processed into a satisfactory configuration with high dimensional accuracy without suffering the effect of heat produced under irradiation of a laser beam. According to the present invention, resist films (1) are first coated on both surfaces of a metal plate (1), and a laser beam (202) is then irradiated to the metal plate (101) from surfaces of the resist films (1) to form a multiplicity of discontinuous through holes (3) in line, while leaving joints (6) as not-processed portions between the adjacent through holes (3). Openings (2) formed in each resist film (1) by the laser cutting are joined with each other to serve as an etching pattern. Next, etching is carried out to etch side walls (6) defining the through holes and also to remove the joints (6), thereby interconnecting the through holes (3) formed in line to form a gap (303a) of a desired shape. Instead of forming the through holes (3) and the joints (6) in the metal plate (101) by irradiating the laser beam (202), non-penetrating cut grooves (51) may be formed in the metal plate (101) with a joint (52) left as a non-processed portion at the bottoms of the cut grooves, followed by removing the joint by etching.