| 摘要 |
<p>PROBLEM TO BE SOLVED: To form a high-accuracy through-holes by preventing deterioration and deformation of a sheet material and deformation of the through-holes caused by the heat dissipation defect of work heat in forming the through-holes which are capable of coping with an increase in I/O pads of a silicon chip and are arrayed approximately to a grid form of a narrow pitch and space by irradiating with a la ser beam. SOLUTION: This piercing method consists in performing the piercing while moving from a piercing point to the next piercing point in forming the through- holes arrayed approximately to the grid form to the prescribed sheet 1 by irradiation with the laser beam 4, in which the piercing is performed while moving the piercing point when the piercing point after the piercing is moved to the next piercing point in such a manner that the ratio of the movement is attained so that the shortest distance is <=50% of the total number of the movements at this time.</p> |
