High-frequency circuit package and sensor module

A high-frequency circuit package for housing a high-frequency circuit, comprising:

• a high-frequency circuit mounting substrate as a first dielectric substrate that includes
• a microstrip line that is connected to the high-frequency circuit formed on an underside surface layer and that is formed on the underside surface layer;
• a waveguide opening that is formed to surround a tip-open portion of the microstrip line and that is formed by not providing a first grounding conductor formed on the underside surface layer;
• a tip-short dielectric waveguide having a length of substantially ¼ of an in-substrate effective propagation wavelength for high-frequency signals in a substrate lamination direction from the waveguide opening;
• a first solder-ball-mounting conductor land group arranged on the first grounding conductor, so as to surround the waveguide opening, at intervals equal to or smaller than ¼ of a free space propagation wavelength for high-frequency signals;
• a second grounding conductor disposed around the high-frequency circuit;
• a third grounding conductor that functions as a return conductor for the high-frequency circuit and for the microstrip line, and that is formed on a substrate inner layer;
• a second solder-ball-mounting conductor land group arranged on the second grounding conductor, so as to surround the high-frequency circuit, at intervals equal to or smaller than ¼ of a free space propagation wavelength for high-frequency signals;
• and
• a third solder-ball-mounting conductor land group that functions to transmit a DC bias and a control signal for driving the high-frequency circuit;
• a mother control substrate as a second dielectric substrate, on which the high-frequency circuit mounting substrate is mounted in such a way that the high-frequency circuit is sandwiched therebetween, the mother control substrate including
• a fourth grounding conductor formed in a region that faces the high-frequency circuit mounted on the high-frequency circuit mounting substrate;
• a plurality of fourth conductor land groups that are electrically connected to the fourth grounding conductor and that are formed at positions facing the first, second, and third solder-ball-mounting conductor land groups;
• a waveguide formed at a position facing the waveguide opening of the high-frequency circuit mounting substrate and formed in a substrate lamination direction;
• and
• a line that transmits a DC bias and a control signal for driving the high-frequency circuit;
• and
• a solder ball group for connecting the first to third solder-ball-mounting conductor land groups with the plurality of fourth conductor land groups, wherein
• the high-frequency circuit is housed in a pseudo shielding cavity formed by the solder balls connected to the second solder-ball-mounting conductor land group and by the second to fourth grounding conductors.