| 摘要 |
<p>PURPOSE:To maintain high heat-dissipating properties and airtightness stably by interposing an alloy layer consisting of a metallic-layer constitutive metal and silicone between a second ceramic substrate and a metallic layer. CONSTITUTION:A first ceramic substrate 11 uses an alumina sintering body as a parent material. First and second ceramic base bodies 11, 10 are joined, interposing a metallic layer 12 composed of a closed loop-shaped aluminum piece, but a transition region 121 is formed particularly between the second ceramic base body 10 and the metallic layer 12, and contributes to the maintenance of bonding force. The second ceramics 10 consists of a plate obtained by pressure-sintering (200kg/cm<2>, 2,000 deg.C, 3hr) high-purity synthetic aluminum nitride powder (grain size of 1mum or less), which is acquired by thermally treating the mixture of high-purity alumina powder and carbon powder under a nitrogen atmosphere for 5hr at 1,600 deg.C and successively removing excess carbon by heating in the presence of oxygen, in the nitrogen atmosphere.</p> |
