High-frequency circuit package and sensor module

Patent metadata

Field	Value
Publication number	US-9070961-B2
Application number	US-200913062349-A
Country	US
Kind code	B2
Filing date	Sep 2, 2009
Priority date	Sep 5, 2008
Publication date	Jun 30, 2015
Grant date	Jun 30, 2015

Abstract

Shielding of high-frequency circuits is achieved using a simple and inexpensive configuration not using any lid. A high-frequency circuit mounting substrate ( 20 ) is disposed, on an underside surface layer of which are disposed high-frequency circuits ( 21 and 22 ) and is formed a first grounding conductor that has same electric potential as grounding conductors of the high-frequency circuits and that surrounds the high-frequency circuits. A mother control substrate ( 3 ) is disposed, on which the high-frequency circuit mounting substrate ( 20 ) is mounted in such a way that the high-frequency circuits are sandwiched therebetween and on which a second grounding conductor is formed in a region facing the high-frequency circuits. Plural first lands are formed on the first grounding conductor of the high-frequency circuit mounting substrate ( 20 ) to surround the high-frequency circuits. Plural second lands are formed that are electrically connected to the second grounding conductor at positions on a surface layer of the mother control substrate ( 3 ) which face the first lands. Plural solder balls ( 30 G 2 ) are disposed for connecting the first lands and the second lands. The high-frequency circuits are housed in pseudo shielding cavities surrounded by the solder balls ( 30 G 2 ), the grounding conductors of the high-frequency circuits, and the first and second grounding conductors.

First claim

The invention claimed is:

1. A high-frequency circuit package comprising:
a first dielectric substrate having a high-frequency circuit formed and disposed on an underside surface layer and having a first grounding conductor that has a same electric potential as a grounding conductor of the high-frequency circuit and that is formed on the underside surface layer to surround the high-frequency circuit;
a second dielectric substrate, on which the first dielectric substrate is mounted in such a way that the high-frequency circuit is sandwiched therebetween, the second dielectric substrate having a second grounding conductor formed in a region that faces the high-frequency circuit; and
solder balls for connecting a plurality of conductor lands and surrounding the high-frequency circuit at positions at which the first and second grounding conductors face each other, the conductor lands being arranged at intervals smaller than ¼ of an operating signal wavelength for the high-frequency circuit, wherein
the high-frequency circuit is housed in a pseudo shielding cavity that is formed due to mutual connection established between the first and second dielectric substrates by the solder balls, and that includes the plurality of solder balls, the first and second grounding conductors, and the grounding conductor of the high-frequency circuit,
the first dielectric substrate includes
a microstrip line that is connected to the high-frequency circuit and that is formed on the underside surface layer;
a waveguide opening formed by partially not providing the first grounding conductor so as to surround a tip-open portion of the microstrip line; and
a tip-short dielectric waveguide that is electrically connected to the waveguide opening and that has the length of substantially ¼ of an in-substrate effective propagation wavelength for high-frequency signals in a substrate lamination direction from the waveguide opening;

the second dielectric substrate includes a waveguide that is formed at a position facing the waveguide opening and that is formed in a substrate lamination direction, and
a plurality of waveguide conductor lands, which are arranged at positions of the first and second grounding conductors facing each other at intervals equal to or smaller than ¼ of a free space propagation wavelength for high-frequency signals so as to surround the waveguide opening and the waveguide, are mutually connected by solder balls to take out an input-output signal of the high-frequency circuit through the waveguide of the second dielectric substrate.

2. The high-frequency circuit package according to claim 1 , wherein
the first dielectric substrate includes, on the underside surface layer,
a first wiring pattern that is connected to the high-frequency circuit and that transmits a DC bias and a control signal for driving the high-frequency circuit; and
first signal lands connected to the wiring pattern;

the second dielectric substrate includes
a DC power source and a control circuit mounted thereon for driving the high-frequency circuit;

the second dielectric substrate includes, on a mounting surface for the first dielectric substrate,
a second wiring pattern for transmitting signals from the DC power source and the control circuit; and
a plurality of second signal lands that are connected to the second wiring pattern and that are formed at positions facing the first signal lands; and

the first and second signal lands facing each other are mutually connected by solder balls so that the DC power source and the control circuit mounted on the second dielectric substrate drive the high-frequency circuit mounted on the first dielectric substrate.

3. The high-frequency circuit package according to claim 1 , wherein the second grounding conductor formed on the second dielectric substrate is electrically connected to the plurality of conductor lands that surround the high-frequency circuit at intervals smaller than ¼ of an operating signal for the high-frequency circuit and is formed on the surface layer or the inner layer of the second dielectric substrate.

4. The high-frequency circuit package according to claim 1 , wherein horizontal and vertical dimensions of a region, which is surrounded by the solder balls for connecting the plurality of conductor lands that are formed to surround the high-frequency circuit at positions at which the first grounding conductor and the second grounding conductor face each other and that are arranged at predetermined intervals smaller than ¼ of an operating signal wavelength for the high-frequency circuit, are set to be smaller than ½ of a free space propagation wavelength for high-frequency signals or set to avoid the length equal to ½ thereof.

5. The high-frequency circuit package according to claim 1 , wherein
a plurality of the high-frequency circuits are formed and disposed on the underside surface layer of the first dielectric substrate,
the first dielectric substrate includes a plurality of the microstrip lines respectively connected to the plurality of high-frequency circuits, a plurality of the waveguide openings, and a plurality of the tip-short waveguides,
the second dielectric substrate includes a plurality of the waveguides formed at positions facing the plurality of waveguide openings and formed in a substrate lamination direction, and
the plurality of waveguide conductor lands, which are arranged on the first grounding conductor and on the second grounding conductor at positions facing each other at intervals equal to or smaller than ¼ of a free space propagation wavelength for high-frequency signals to surround the plurality of waveguide openings and the plurality of waveguides, are mutually connected by the solder balls to take out an input-output signal of each of the high-frequency circuits through the waveguides of the second dielectric substrate.

6. The high-frequency circuit package according to claim 1 , wherein the high-frequency circuit is housed in a non-airtight manner in between the first dielectric substrate and the second dielectric substrate.

7. A sensor module comprising:
the high-frequency circuit package according to claim 1 ; and
an antenna that is disposed on the second dielectric substrate on the opposite side of the mounting surface for the first dielectric substrate and that is connected to the waveguide.

8. 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 fr

Assignees

• Suzuki Takuya
• Mitsubishi Electric Corp

Inventors

• Suzuki Takuya

Classifications

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/721

  of bump connectors · CPC title

• H10W90/701

  characterised by the relative positions of pads or connectors relative to package parts · CPC title

• H10W72/00

  Interconnections or connectors in packages · CPC title

• H10W44/248

  for antennas · CPC title