Patent ID: 6146920
Filing Date: 2000-11-14
Classification: H01L,H05K,Y10T

Abstract:
A method for forming bumps in an LSI package, comprising the steps of:mounting semiconductor chips onto a flexible printed circuit board;temporarily fixing electrically conductive balls by using fixing liquid comprising one selected from a group consisting of flux, solder paste and an adhesive containing an electrically conductive agent, onto pads which are provided on said flexible printed circuit board so as to be electrically connected to said semiconductor chips;winding up said flexible printed circuit board having said electrically conductive balls temporarily fixed thereto, onto a reel;forming bumps by feeding out said flexible printed circuit board having said electrically conductive balls temporarily fixed thereto from said reel, and heating said flexible printed circuit board;winding up said flexible printed circuit board having said bumps formed thereon, onto another reel; andforming LSI packages by cleansing and trimming said flexible printed circuit board.