ELASTIC LEAD FOR ELECTRICAL AND MECHANICAL CONNECTION OF INTEGRATED CIRCUIT CHIP PACKAGE TO SUBSTRATE SURFACE AND PREPARATION THEREOF

摘要

PURPOSE: To prolong the lifetime by providing an elastic lead, including at least two regions different in thickness for avoiding the shortening of the life of a surface-mounted integrated circuit chip package due to heat. CONSTITUTION: An integrated circuit chip package 30 mounted on the surface of a board 36 has a lead frame 32. An elastic lead 32 includes at least two regions different in thickness. A first region 42 has a uniform thickness t and is formed adjacent to the package 30, when the lead 32 connects the package 30 to the surface of the board 36. A second region 44 has a reduced thickness tr and is formed at a position to improve the elasticity of the lead 32 during a thermal cycle, when the lead 32 connects the package 30 to the surface of the board 36, where tr