| 摘要 |
PURPOSE:To realize an inexpensive film substrate consisting only of two sheets of Cu foil by a method wherein two sheets of Cu foil are pressedly bonded by a thermosetting, insulating adhesive and one of the Cu foil sheets is provided with a conductive pattern while the other is provided with a supporting pattern overlapping said conductive pattern. CONSTITUTION:Cu foil 11 and 12 sandwitching a thermosetting, insulating adhesive 13 are pressed to form a film substrate 10. Next, the Cu foil 11 is etched into a frame pattern 17, a pad 15 located within the pattern 17 for fixing a semiconductor device, and a conductive pattern 14 consisting of a plurality of electrode leads 16 running in four directions. The Cu foil 12 is etched into a supporting pattern 18 encircled by a rear frame pattern 19 and rear frame leads 20. The supporting pattern 18 laps over the pad 15 and the leads 16 on the Cu foil 11, and are specifiedly wire bonded to them. An inexpensive film substrate without using expensive, heat resisting plastic film is obtained. |
