| 摘要 |
PURPOSE:To prevent the deterioration of elements caused by radiated heat by a method wherein the bottom periphery of a cap made of conductor and a through-hole are coated with a low melting point glass, and the package body is sealed with the cap by fusing the low melting point glass on heating the cap through the high-frequency induction heating system. CONSTITUTION:When high-frequency current is passed through a high-frequency heating coil 12, a high-frequency electric field generates, and the high-frequency current flows through the cap 13 arranged in the electric field. Since the through-hole 14 is formed at the center of the cap 13, the high-frequency current does not flow through the center but flow through the periphery, resulting in the generation of Joule heat. This heat does not transfer to the center because the through-hole 14 have a very high thermal resistance. Thereby, the temperature rapidly increases only in the periphery of the cap 13, and the low melting point glass 15 coating its bottom fuses; thus, the cap 13 can be sealed in a short time. Accordingly, the amount of radiated heat out of the center of the cap 13 bottom markedly reduces, and the temperature increase of the element 9 can be inhibited; then, the deterioration in characteristics of the element 9 can be prevented. |
