| 摘要 |
<p>PURPOSE:To prevent the generation of warps and cracks by using soft metals or soft alloys with high plastic deformability, for the join of the connecting structure of base material or covering part material made of aluminum nitride with connecting part material for the base material or covering material. CONSTITUTION:A metallized layer 2 is formed on a part of the surface of an aluminum nitride substrate 1. To this metallized layer 2, a lead frame 3 is soldered with metallic solder, etc., and joined. Buffering material 13, made of soft metals such as copper, etc., with nickel solder layers formed on the surfaces is interposed between the metallized layer 2 and lead frame 3. Besides, a semiconductor element 4 such as an FFT, etc., with a large amount of heat generation is mounted at a specified position of the aluminum nitride substrate 1, and it is connected to the metallized layer 2 or lead frame 3 with pieces of bonding wire 5. This makes it possible to prevent the generation of cracks or warps, as almost all the stress generated by the difference between the thermal expansion coefficients of the aluminum nitride substrate 1 and connecting part material 3 is absorbed by the plastic deformation of the buffering material 13.</p> |
