Patent ID: 9095931
Filing Date: 2015-08-04
Classification: B23K,H01L,H05K

Abstract:
1. A laser processing method for forming a laser processed hole in a workpiece configured by bonding a first member formed of a first material and a second member formed of a second material, said laser processed hole extending from said first member to said second member, said laser processing method comprising the steps of: detecting the wavelength of plasma light generated by applying a pulsed laser beam to said first member and said second member; continuing the application of said pulsed laser beam at a first power until the light intensity of said plasma light generated from only said first member and detected is decreased to reach a predetermined value; applying said pulsed laser beam at a second power which is lower than said first power and generates no cracks in said first member when the light intensity of said plasma light has reached said predetermined value; and stopping the application of said pulsed laser beam when said plasma light generated from said second member is detected.