| 摘要 |
PURPOSE:To prevent stress induced due to the thermal expansion coefficient difference between a pellet and a base from concentrating on a glass-sealed section. CONSTITUTION:A buffer material layer 14 formed of silver paste 15 whose main component is silver is formed as thick as 0.020mm or above on a base 11 of alumina ceramic, and a silicon pellet 22 is bonded onto the buffer material layer 14 with a gold-silicon eutectic layer 21. By this setup, a deformation difference between a base 11 and a pellet 22 caused by a thermal expansion coefficient difference between alumina ceramic and silicon at the change of temperature can be absorbed by the plastic deformation of the buffer material layer 14, so that stress induced in the base 22 due to a deformation difference can be restrained, and as a result a glass-sealed part 24 can be protected against separation and cracks. |
