A high-frequency package on which a high-frequency semiconductor device, which operates in a high frequency band such as a microwave band and a millimeter-wave band, is mounted is often housed in a cavity that is airtightly and electrically shielded with a metallic frame or the like, considering environment resistance, operational stability, corrosion resistance, and the like.
Patent Document 1 discloses a technique in which a control signal line is wired on a dielectric multilayer substrate, a metallic frame is arranged on the dielectric multilayer substrate, and a microwave integrated circuit is mounted in the metallic frame, thereby improving input/output isolation of the integrated circuit, and in which airtight sealing is enabled by welding.
Patent Document 1: Japanese Patent Application Laid-open No. 2001-203290