| 摘要 |
PURPOSE:To make the generation of a crack and a breaking in an insulating substrate to nil, to make perfect the hermetic sealing of the interior of a package and to actuate a semiconductor element normally and stably over a long period of time by a method wherein the outer peripheral edge of a metallized metal layer provided on the base of the recessed part of the substrate is buried in the substrate and at the same time, the thickness of the buried part of the layer is specified. CONSTITUTION:Ceramic in an insulating substrate 1 and molybdenum, tungsten and the like, which are contained in a metallized metal layer 3, are different from each other in thermal expansion coefficient. Therefore, a stress due to a difference in thermal expansion coefficient between both of the substrate 1 and the layer 3 is generated and this is inhered in the interior of the substrate 1 when the thickness of the buried part, which is buried in the substrate 1, of the layer 3 is less than 15mum, the stress, which is made to inhere in the substrate 1, is reduced, a stress at the time of welding of a cap body 2 can not be cancelled completely and a crack and a breaking are generated in the substrate 1. Moreover, when the thickness of the buried part exceeds 45mum, a defective lamination is generated between the layer 3 in the outer periphery part of the base of the substrate 1 and the ceramic and accordingly an incomplete hermetic sealing is generated in the substrate 1. Therefore, the thickness of the site, which is buried in the substrate 1, of the layer 3 is specified within a range of 15 to 45mum.
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