Method of manufacturing a thermally conductive substrate with leadframe and heat radiation plate

摘要

A lead frame (100) is provided on a top surface of an electrically insulating sheet (101). A radiation plate (102) is attached to the bottom surface of the insulating sheet. By locating end portions of the radiation plate inside the periphery of the insulator sheet, it is possible to ensure a sufficiently large creeping distance between the lead frame and the radiation plate without decreasing a lead frame area on which components can be actually mounted. This arrangement acts to prevent electrical discharge between the lead frame and the radiation plate.