| 摘要 |
PURPOSE:To prevent generation of cracks in a heat sink and to improve air- tightness of a semiconductor device by providing a convex cross section to the heat sink and by forming a cross section of a boundary between a flat part and a vertical part thereof to an arc. CONSTITUTION:An IC chip mount part of a ceramic package substrate 1 is hollowed to a rectangle or a square and a convex heat sink 6a (aluminum nitride) of high heat conductivity is inserted thereto from a rear of a ceramic package substrate 1 and attached through a bonding material 7a. A cross section of a boundary between a flat part 8a and a vertical part 9a of the heat sink 6a is formed to an arc 10. Stress concentration which is produced in the boundary between the flat part and the vertical part of the heat sink 6a can be prevented in a mechanical strength test of a package by forming the heat sink 6a to such a shape. Generation of cracks in a heat sink can be prevented and air-tightness of a semiconductor device can be improved in this way. |
