| 摘要 |
PURPOSE:To make a stepped part of an island large by a method wherein a holding tie bar which is extended in a direction nearly perpendicular to an extension direction of a tie bar and which connects the tie bar to a frame body is installed between the tie bar and the frame body of a lead frame and a mounting angle of the tie bar and the holding tie bar is changed. CONSTITUTION:Large cutouts are formed at four corner parts of a frame body 11; holding tie bars 16 crossing at a right angle to tie bars 14 are extended rectilinearly and are connected to the frame body 11. The holding tie bars 16 are formed at a total of four parts in parallel at two parts each on both sides of the tie bars 14; they are formed to be more slender than the tie bars 14 so as to be deformed mechanically more easily than the tie bars 14. Ends of leads 15 are held by using tie bars 16' in the same manner. Since a change in a mounting angle of the tie bars 14 and the holding tie bars 16 absorbs a stress of a drawing operation of an island 13, its absorption is executed mainly by a bending deformation of a metal material at amounting parts of the tie bars 14 and the holding tie bars 16. |
