| 摘要 |
PURPOSE: To remove dross and spatter easily, surely and quickly while a fine and highly accurate form is kept without causing deformation after laser bear machining, relating to a method of working a lead frame. CONSTITUTION: Both surfaces of a metal board 1 are coated with chemical corrosion-resistant films 2, and, cutting grooves 3 passing through the metal board 1 are, by applying a laser beam, formed according to the form of a lead frame. Next, the metal board 1 after laser beam machining is dipped in etchant for chemical polishing process, and further, ultrasonic vibration from an ultrasonic wave generator part is applied to the metal board 1 through the etchant. At that tire, with the use of an acoustic lens, the ultrasonic vibration is locally focussed at least on fine part such as art inner lead, and, convergence position of the ultrasonic vibration is scanned in the area where the fine part exists. |
