| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high quality substrate at low cost by forming a heat dissipating insulating film on the rear surface of a ceramic substrate. SOLUTION: An insulating film 11 mixed with powder exhibiting high thermal conductivity is formed on the rear surface of a ceramic substrate 1 and composed of resin based paint mixed with powder exhibiting high thermal conductivity. A polyester based or epoxy based heat resistant resin is suitably used as the resin based paint. Copper powder is suitably used as the powder exhibiting high thermal conductivity being mixed with the resin based paint composing the insulating film 11. Mixing ratio of the powder exhibiting high thermal conductivity to the basic resin is set in the range of 30-150 wt.%: 100 wt.%. Mixing ratio is determined appropriately depending on the quantity of heat being dissipated. When the powder exhibiting high thermal conductivity and the resin based paint are mixed and kneaded, individual powder is previously coated with resin and thereby excellent electric insulation is ensured without having adverse effect on the quality of a package.
|
