| 摘要 |
PURPOSE:To cool a ceramic wiring substrate effectively, by providing input and output pins on the lower surface of the ceramic wiring substrate, on which a pluralityof integrated circuit chips are mounted so that the pins are protruded, and constituting a metal cap, on which a heat radiating member covering the cap in an airtight manner is fixed on the upper surface. CONSTITUTION:Many input and output pins 14 of PGA are protruded from the lower surface of a ceramic multilayer wiring substrate 10. A sealing metallized part 15 is formed on the upper surface so as to surround integrated circuit chips 11. On the surface of a metal cap 16, heat insulating fins 18 made of aluminum alloy are bonded by a bonding agent 19 having good heat conductivity beforehand. A metallizing pattern 20 is formed in the mounting gap between the integrated circuit chip 11. Metal heat conducting plates 21 are inserted in a part under the metal cap 16. In this constitution, excellent heat radiating effect can be obtained with high mounting density being maintained. |
