JP2000138495A - Package of high-frequency integrated circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a high-frequency integrated circuit to be mounted with sufficient space in the millimetric wave range where packaging conditions are too severe to prevent the propagation of waveguide modes due to limitations of the width of a package. SOLUTION: A high-frequency circuit portion 3 comprising semiconductor devices, etc., is mounted on a package base 1 and hermetically sealed with a dielectric sealing plate 4 made of dielectric. A radio wave absorber 5 is bonded to the outside of the dielectric sealing plate 4. The package base 1 with the radio wave absorber 5 bonded is further covered with a cap 6 of metal or others to be electromagnetically shielded. This allows reductions in the entry of too high external signals to be prevented by the radio wave absorber 5 and the leakage of internal signals outside a package.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency integrated circuit package structure, and more particularly, to a structure effective for a millimeter wave region as a frequency band, which is sealed with a lid made of a dielectric material, and The present invention relates to a high-frequency integrated circuit package in which a radio wave absorber is mounted between a lid and a cap for electric shielding.

[0002]

2. Description of the Related Art FIG.
As shown in FIG. 4, a structure surrounded by a conductor wall was employed.

FIG. 3 is a perspective view showing the structure of a conventional high-frequency package, and FIG. 4 is a sectional view of the prior art shown in FIG.

In FIG. 3 and FIG.
The circuit board 33 mounted on the circuit board 1 is surrounded by a conductor wall formed by a cap 36 for electromagnetic shielding.

[0005]

However, in the case of such a conventional structure, especially when the power difference at the same frequency is large between the input and the output as in an amplifier having a high gain, the width of the conductor wall is large. If the frequency is below the cutoff frequency of the propagation mode of the waveguide, feedback occurs at the input and output, causing problems such as oscillation and deterioration of frequency characteristics.

Therefore, the width of the conductor wall of the package needs to be sufficiently smaller than the cutoff of the waveguide mode. However, in the millimeter wave region such as 60 GHz, when the design is made in consideration of the cutoff of the waveguide, the width of the conductor wall is about 2 mm, and it is difficult to mount and arrange an element such as an actual MMIC.

When the conductor wall is formed with a width larger than the cut-off of the waveguide, feedback occurs between input and output, causing problems such as oscillation. In this case, the amount of feedback between input and output can be reduced by attaching a radio wave absorber or the like to the wall surface of the conductor wall, and oscillation can be avoided.

However, in a semiconductor device operating at a millimeter wave, a radio wave absorber for generating OUT gas cannot be arranged in a hermetically sealed package due to the reliability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a novel high-frequency integrated circuit package capable of solving the above-mentioned disadvantages inherent in the prior art. To provide.

[0010]

In order to achieve the above object, a high-frequency integrated circuit package according to the present invention comprises a package base on which a high-frequency circuit board and the like are mounted and the high-frequency circuit board and the like on the package base. A dielectric sealing plate made of a dielectric material disposed on the package base so as to be sealed, a radio wave absorber disposed outside the dielectric sealing plate, and the radio wave absorber; A metal cap or the like disposed to surround the radio wave absorber so as to shield the radio wave absorber.

A matching dielectric substrate is provided between the dielectric sealing plate and the radio wave absorber.

The relative permittivity of the dielectric sealing plate is set to 10 or less.

The high-frequency integrated circuit package according to the present invention also includes a package base on which a high-frequency circuit board and the like are mounted, a package metal wall formed on the package base so as to surround the high-frequency circuit board and the like, and A sealing dielectric substrate disposed on a package metal wall, a matching dielectric substrate formed on the sealing dielectric substrate, and a radio wave absorber formed on the matching dielectric substrate And a cap for electromagnetic shielding mounted on the package base so as to surround each of the components arranged on the package base.

[0014]

Next, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment] FIG. 1 is a perspective view showing a first embodiment of the present invention.

[Configuration of First Embodiment] Referring to FIG. 1, a high-frequency circuit section 3 including a semiconductor element, a bypass capacitor and the like is mounted on a package base (vess carrier) 1 and an LID (dielectric material) is used. It is hermetically sealed by a dielectric sealing plate 4 as a lid. A radio wave absorber 5 is attached to the outside of the dielectric sealing plate 4.

The package base 1 to which the radio wave absorber 5 is attached is further electromagnetically shielded by a cap 6 made of an electromagnetic shielding metal or the like, so that a signal from the outside that cannot be prevented by the radio wave absorber 5 is prevented. A configuration is adopted to reduce intrusion and leakage of signals inside the package to the outside.

[Operation of First Embodiment] Next, the operation of the first embodiment will be described. A functional circuit such as an amplifier is mounted inside the package. In the case of a conventional package in which a high-frequency circuit or the like is mounted and the entire surface is covered with metal or the like, there is a mode in which a portion surrounded by the package wall propagates as a waveguide, and there is a level difference between input and output of the amplifier. In such a case, there is a problem in that feedback occurs from the input to the output and oscillation occurs.

In the first embodiment according to the present invention, since the ceiling of the upper surface of the package base 1 on which the high-frequency circuit and the like are mounted is sealed with the dielectric sealing plate 4, the waveguide is guided. Tube mode stops propagating.

A radio wave absorber 5 is mounted on the upper surface of the lid outside the dielectric sealing plate 4 used for hermetic sealing to reduce unnecessary radiation and prevent oscillation and the like.

Further, for general use in a wide frequency range, a high dielectric constant has an effect. Therefore, it is desirable to reduce the dielectric constant as much as possible and set the relative dielectric constant to 10 or less.

[Embodiment 2] Next, a second embodiment of the present invention will be described.
An embodiment will be described with reference to the drawings.

FIG. 2 is a sectional view showing a second embodiment according to the present invention.

[Configuration and Operation of Second Embodiment] Referring to FIG. 2, a circuit board 23 is provided on the surface of a package base 21.
Is mounted, and a sealing dielectric substrate 24 is disposed on a package metal wall 22 provided around a circuit board 23 of the package base 21.

A matching dielectric substrate 27 is provided on the upper surface of the sealing dielectric substrate 24, and a radio wave absorber 25 is provided on the matching dielectric substrate 27.

The circuit board 2 is mounted on the package base 21.
3. An electromagnetic shielding cap 26 is attached so as to surround the sealing dielectric substrate 24, the matching dielectric substrate 27, and the radio wave absorber 25.

In the second embodiment, as shown in FIG. 2, in order to improve the characteristics by using a radio wave absorber for millimeter waves, an impedance matching substrate is further provided on the sealing dielectric substrate 24. Is inserted. By adopting such a configuration, it is particularly effective in the second embodiment to adjust the thickness of the dielectric to match the impedance to the radio wave absorber 25 with respect to the operating frequency.

[0028]

As described above, according to the present invention, in order to prevent the propagation of the waveguide mode, the package is mounted with a sufficient space even in the millimeter wave region where the mounting conditions are severe due to the limitation of the package width. It is possible to

Also, since the radio wave absorber is attached to the outside of the hermetically sealed package, high reliability can be maintained without considering the OUT gas generated by the resin and the like contained in the radio wave absorber. It is.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment according to the present invention.

FIG. 2 is a sectional view showing a second embodiment according to the present invention.

FIG. 3 is a perspective view of a conventional technique.

4 is a cross-sectional view of the prior art shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Package base 3 ... High frequency circuit part 4 ... Dielectric sealing plate 5 ... Radio wave absorber 6 ... Electromagnetic shielding metal cap (CAP) 21 ... Package base 22 ... Package metal wall 23 ... Circuit board 24 ... Dielectric for sealing Body substrate 25 Radio wave absorber 26 Electron shield cap (CAP) 27 Dielectric substrate for matching

Claims (5)

[Claims] 1. A dielectric material comprising a package base on which a high-frequency circuit board and the like are mounted, and a dielectric disposed on the package base so as to seal the high-frequency circuit board and the like on the package base. A sealing plate, a radio wave absorber disposed outside the dielectric sealing plate, and a metal cap or the like disposed to surround the radio wave absorber so as to shield the radio wave absorber. A high frequency integrated circuit package characterized by having: 2. The high frequency integrated circuit package according to claim 1, further comprising a matching dielectric substrate provided between said dielectric sealing plate and said radio wave absorber. 3. The high-frequency integrated circuit package according to claim 1, wherein the relative permittivity of the dielectric sealing plate is set to 10 or less. 4. A package base on which a high-frequency circuit board or the like is mounted, and a package metal wall formed on the package base so as to surround the high-frequency circuit board or the like.
A sealing dielectric substrate provided on the package metal wall, a matching dielectric substrate formed on the sealing dielectric substrate, and a radio wave absorption formed on the matching dielectric substrate A high-frequency integrated circuit package comprising: a body; and an electromagnetic shielding cap mounted on the package base so as to surround the components disposed on the package base. 5. The dielectric substrate for sealing has a relative dielectric constant of 10
The high-frequency integrated circuit package according to claim 4, further comprising: