| 摘要 |
PURPOSE:To avoid defects caused by thermal expansion by a method wherein a pellet is partially bonded to a mounting part so as to make a bonding area smaller. CONSTITUTION:When copper alloy is employed as a material for a lead frame 2, a large difference exists between the thermal expansion coefficient of a pellet 8 and the thermal expansion coefficient of the lead frame 2. Therefore, when a thermal test such as a temperature cycle test or a heat shock test is carried out, distortion is created in the lead frame 2. As a result, defects such as disconnection of an aluminum electrode or short circuit are created in the outer circumference of the pellet 8 which has a large size due to high integrity. If unevenness 4 is provided on the tab 3 of the lead frame 2 so as to make the pellet 2 bonded to the tab 3 at the protruded parts only, the tab 3 can be deformed between the protruded parts without being restricted by the pellet 8. If the tab 3 is partially deformed between the respective protruded parts, application of stress to the pellet 8 can be avoided or suppressed.
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