Ball-arranging substrate for placement of bumps, ball-arranging head, ball-arranging apparatus and method for arranging balls

A ball-arranging substrate comprising a substrate with a main surface, a plurality of ball-arranging holes formed on the main surface for sucking and holding minute electroconductive balls at the locations corresponding to those of electrodes formed on a semiconductor device or a printed circuit board, wherein when light illuminates the ball-arranging surface to allow optical recognition of the arrangement of the minute electroconductive balls by means of the light reflected by the minute electroconductive balls and by the main surface, the wave length of the light of the light source is set in the range of 300 to 900 nm, and the reflectivity is made not more than 50% based on the light source. A reflective mirror should be provided on the rear surface of the substrate opposite to the light source, in the case when the substrate is transparent to the irradiated light.