| 摘要 |
<p>PURPOSE:To increase the strength of the part whereon high stress is to be imposed during helium applying step by a method wherein a high purity alumina is used for a base material, trenches are provided on the sealing surface of the base and a light transmissive alumina is used. CONSTITUTION:The whole body of an ultraviolet ray erasable semiconductor element 106 is covered with a light transmissive alumina cap 101 while a high purity alumina base 102, a lead 103 and said cap 101 are airtight-sealed by a low melting point glass 104. Trenches are provided on the sealing surface of the high purity base 102. Besides, a high melting point glass 105 is arranged on the boundary part between the light transmissive alumina cap 101 and the low melting point glass 104. On the other hand, the light transmissive alumina in fine particle diameter is applicable to a cap material. When the particle diameter becomes finer, the structure of the cap material becomes finer while reducing the cavities and avoiding the development of cracking phenomenon. Through these procedures, the strength of a package can be increased thereby enabling the package to be formed thinner.</p> |
