| 摘要 |
PURPOSE:To avoid the occurrence of the defect caused by the insufficient wetting by attaching the pellet to th Au-Si eutectic layer which is formed previously on the Au layer of the lead frame via the different Si bar. CONSTITUTION:Si bar 2 featuring the smooth surface is pressure-bonded to the gold plated layer on the tab on lead frame 1 to from Au-Si eutectic layer 3 previously on the surface of the gold layer. Then bar 2 is removed, and the Si pellet is welded to layer 3. With this method, the insufficient wetting caused by the residual gas, pinholes or the contamination of the surface can be avoided owing to existence of the smooth Au-Si eutectic layer formed previously. Thus, the defect of the device can be reduced. |
