JP2008244289A - Electromagnetic shielding structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an electromagnetic shielding structure which is easy to manufacture an object having a high electromagnetic shield property, at low cost. <P>SOLUTION: The electromagnetic shielding structure is constructed, in a manner such that high-frequency functional components MC, MC mounted on a dielectric substrate 20A are covered with an electromagnetic shield component. On the dielectric substrate, transmission lines 7a, 7b, 9a-9c, an inside layer ground pattern 11, a pseudo coaxial vertical feeder line, and a plurality of hollow ground through holes 17a which are located at interval so as to enclose each high-frequency functional component are located. On the electromagnetic shielding component 30, a shield ring portion 21 from which a plurality of columnar conductors 21a to be inserted into each of a plurality of the hollow ground through holes protrude, and a cover portion 23 covering the shield ring are located, and the distance between the adjacent hollow ground through holes is smaller than 1/2 the effective in-substrate wavelength of a high-frequency signal used in the high-frequency functional component. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electromagnetic shield structure, and more particularly, to an electromagnetic shield structure that shields electromagnetic waves from a high-frequency functional component that is mounted on a wiring board and operates in a high frequency band such as a microwave band or a millimeter wave band.

  In devices such as wireless local area networks (LANs) and in-vehicle radars that use electromagnetic waves in high frequency bands such as microwave bands and millimeter wave bands, microwave integrated circuits (MIC) and monolithic / microwave integrated circuits ( High-frequency functional parts equipped with high-frequency integrated circuits such as MMIC (Monolithic MIC), such as amplifiers, phase shifters, and attenuators, cause electromagnetic coupling with other high-frequency noise radiation sources, and unnecessary operations such as oscillation due to characteristic fluctuations and feedback Therefore, electromagnetic shielding is applied to the high-frequency functional component.

  For example, in Non-Patent Document 1, the MMIC is flipped on the lower surface of an alumina single-layer substrate in which a microstrip transmission line disposed on the outer surface and a coplanar waveguide disposed on the inner surface are connected through holes. A package structure is described in which the MMIC is hermetically sealed by chip bonding and fixing a cap member to an alumina single layer substrate so as to cover the MMIC.

  In Non-Patent Document 2, a metal frame is provided on the lower surface of a multilayer alumina substrate using a thin film wiring technique, and a millimeter wave device such as MMIC is flip-chip bonded to the lower surface of the multilayer alumina substrate, and the upper surface of the multilayer alumina substrate is provided. A package structure is described in which a signal is transmitted from a provided microstrip line to a millimeter wave device by through connection using electromagnetic coupling.

Yoji Ohashi and three others, “MMIC Modules for 76 GHz Automotive Radar Sensors”, MWE '99 Microwave Workshop Digest [WS12-4] Takehiro Okumichi and 6 others, “Development of Millimeter-Wave Interconnection Technologies”, MWE 2000 Microwave Workshop Digest [WS5-1]

  As in the package structure described in Non-Patent Document 1, in the package structure in which the MMIC flip-chip bonded to the lower surface of the alumina substrate is hermetically sealed with the cap member, at least the area of the alumina substrate in the region where the cap member is fixed is used. Surface accuracy must be increased. Further, as in the packaging structure described in Non-Patent Document 2, in a package structure in which a metal frame is provided on the lower surface of the alumina substrate and a millimeter wave element such as MMIC is flip-chip bonded to the lower surface of the alumina substrate, alumina is used. In order to improve the airtightness between the substrate and the metal frame, it is necessary to improve the surface accuracy of the alumina substrate and the manufacturing accuracy of the joint at least in the region where the metal frame is fixed. However, in the case of an alumina substrate and a dielectric substrate other than the alumina substrate, if it is attempted to increase the surface accuracy and the manufacturing accuracy of the joint, the manufacturing cost increases.

  The present invention has been made in view of the above, and an object of the present invention is to obtain an electromagnetic shield structure that can easily form a high electromagnetic shielding property at a low cost.

  The electromagnetic shield structure of the present invention that achieves the above object is mounted on a dielectric substrate having a transmission line, an inner layer ground pattern that forms a pair with the transmission line, and a pseudo coaxial vertical feed line, and the dielectric substrate, A high-frequency functional component connected to the pseudo-coaxial vertical feed line, a plurality of hollow ground through-hole portions formed on the dielectric substrate at intervals to surround the high-frequency functional component, and connected to the inner layer ground pattern, A plurality of columnar conductor portions that are inserted into each of the plurality of hollow ground through-hole portions project to form a frame-shaped shield ring portion in which a space for accommodating a high-frequency functional component is formed, and covers the shield ring portion The distance between the hollow ground through holes adjacent to each other is ½ of the effective wavelength in the substrate of the high frequency signal used in the high frequency functional component. It is characterized in that it is fully.

  In the electromagnetic shield structure of the present invention, the inner layer ground pattern, the plurality of hollow ground through holes, the plurality of columnar conductor portions, the shield ring portion, and the lid portion form a space for electromagnetically shielding the high-frequency functional component. . Since the plurality of hollow ground through holes are provided at intervals of less than half of the effective wavelength in the substrate of the high frequency signal used in the high frequency functional component, the dielectric substrate, the shield ring portion, and the lid portion Even if the high-frequency functional component is not hermetically sealed, high electromagnetic shielding properties can be easily obtained. Since the surface accuracy of the dielectric substrate and the manufacturing tolerance of the shield ring portion can be relaxed, according to the present invention, an electromagnetic shield structure with high electromagnetic shielding properties can be formed at low cost.

  Hereinafter, embodiments of the electromagnetic shield structure of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below.

Embodiment 1 FIG.
1 is a cross-sectional view schematically showing an example of an electromagnetic shield structure, FIG. 2 is a side view schematically showing a columnar conductor portion, a shield ring portion, and a lid portion constituting the electromagnetic shield structure shown in FIG. 3 is a top view schematically showing the electromagnetic shield structure shown in FIG. 1, and FIG. 4 is a bottom view schematically showing a shield ring portion constituting the electromagnetic shield structure shown in FIG.

The electromagnetic shield structure S ₁ shown in FIG. 1 includes a dielectric substrate 20A, high-frequency functional components MC and MC mounted on the lower surface of the dielectric substrate 20A, and a high-frequency functional component MC and MC formed of a conductive material. And an electromagnetic shielding member 30 for covering. The illustrated dielectric substrate 20A is a multilayer dielectric substrate in which a plurality of dielectric layers 1 are laminated, and the dielectric substrate 20A has transmission lines, vias, and the like of a predetermined pattern.

Specifically, as shown in FIG. 1, FIG. 3 and FIG. 4, the signal vias 3a, 3b and the signal via 3a for transmitting a high-frequency signal to the high-frequency functional parts MC, MC are arranged so as to surround the planar view. A plurality of ground vias 5a, a plurality of ground vias 5b arranged so as to surround the signal via 3b in plan view, transmission lines 7a and 7b arranged on the upper surface of the dielectric substrate 20A, and arranged on the lower surface of the dielectric substrate 20A Transmission lines 9a to 9c and internal transmission lines (not shown). Each ground via 5a surrounding the signal via 3a constitutes a pseudo coaxial vertical feed line Vf _1, the ground vias 5b surrounding the signal via. 3b constitutes a pseudo coaxial vertical feed line Vf ₂ Yes.

  In addition to the transmission line described above, the dielectric substrate 20A is formed so as to be paired with the transmission line and connected to the ground vias 5a and 5b, and around the upper opening end of the through hole TH. A hollow ground through hole made of a cylindrical conductor layer formed on the wall surface of the through hole TH, a front surface ground pattern 13a disposed on the back surface, a back surface ground pattern 15a disposed around the lower opening end of the through hole TH 17a and the like. Although one through hole TH and a hollow ground through hole 17a formed on the wall surface of the through hole TH appear in FIG. 1, the dielectric substrate 20A has a plurality of through holes and wall surfaces of the individual through holes. Hollow ground through holes 17a to 17g (see FIG. 3) formed above are formed. The hollow ground through holes 17 a to 17 g are provided on the dielectric substrate 20 </ b> A so as to surround the high-frequency functional parts MC and MC, and are connected to the inner layer ground pattern 11.

  Each high-frequency functional component MC, MC is a resin-sealed product with resin sealing or a metal-sealed product with metal sealing, and one of the high-frequency functional components MC, MC is a high-frequency functional component. MC is fixed to the transmission line 9a, and the other high-frequency functional component MC is fixed to the transmission line 9c with solder S. One end of the transmission line 9a is connected to the lower end of the signal via 3a, and one end of the transmission line 9c is connected to the lower end of the signal via 3b. The two high-frequency functional parts MC and MC are connected to each other by a transmission line 9b.

  On the other hand, the electromagnetic shield member 30 includes a frame-shaped shield ring portion 21 that surrounds each high-frequency functional component MC, MC and forms a space Cv (see FIG. 1) for accommodating the high-frequency functional component MC, MC, and a shield ring. A cover body portion 23 that covers the portion 21 and closes the space Cv. The shield ring portion 21 and the cover body portion 23 are formed of a conductive material such as a metal or an alloy and are fixed to each other. Yes. As shown in FIGS. 2 to 4, a plurality of columnar conductor portions 21 a to 21 g protrude from the upper surface of the shield ring portion 21, and these columnar conductor portions 21 a to 21 g are formed in the hollow ground through holes 17 a to 17 g. The shield ring portion 21 is engaged with the dielectric substrate 20A by being inserted and brought into contact with the hollow ground through holes 17a to 17g. At this time, one columnar conductor is inserted into one hollow ground through hole.

  As shown in FIG. 2, in order to make each columnar conductor part 21a-21g contact each corresponding hollow ground through-hole 17a-17g reliably, each columnar conductor part 21a-21g protrudes to the inner wall side of a hollow ground through-hole. Convex parts are formed. However, in FIG. 2, only a total of two convex portions appear, that is, the convex portion 22a formed on the columnar conductor portion 21a and the convex portion 22e formed on the columnar conductor portion 21e. Each convex portion presses the inner wall surface of the hollow ground through hole when the columnar conductor portion is inserted into the hollow ground through hole.

  The electromagnetic shield member 30 with the predetermined columnar conductor portions 21a to 21g engaged with the hollow ground through holes 17a to 17g is then soldered with the columnar conductor portions 21a to 21g to the hollow ground through holes 17a to 17g (see FIG. 1) or is fixed to the dielectric substrate 20A by fixing with a conductive adhesive. The inner layer ground pattern 11, the hollow ground through holes 17a to 17g, the columnar conductor portions 21a to 21g, the shield ring portion 21, and the lid portion 23 form a shield space for electromagnetically shielding the high-frequency functional components MC and MC. The

In the electromagnetic shield structure S ₁ having such a structure, a distance D (see FIG. 3) between two hollow ground through holes 17a to 17g adjacent to each other is a high frequency signal substrate used in each of the high frequency functional components MC and MC. It is selected to be less than half of the inner effective wavelength (effective wavelength in the dielectric substrate 20A). When the distance D is selected as described above, high electromagnetic shielding properties for the high-frequency functional parts MC and MC can be easily obtained by the electromagnetic shielding member 30. For this reason, the high-frequency noise radiation source such as the line discontinuity part and the wire connection part outside the shield space and the high-frequency noise radiation source inside the shield space are electromagnetically coupled to each other, so that each high-frequency functional component MC, MC Unnecessary operations such as fluctuations in characteristics and oscillation due to feedback can be suppressed. In order to obtain a high electromagnetic shielding property by the electromagnetic shielding member 30, it is preferable that the distance D is as small as possible, and the two through holes TH and TH having a desired inner diameter are adjacent (close) to each other. Regarding the interval between the two through holes TH and TH when forming, the manufacturing limit value is the lower limit value.

  Further, since it is not necessary to hermetically seal each high-frequency functional component MC, MC, the surface accuracy of the dielectric substrate 20A, particularly the surface accuracy of the lower surface, the manufacturing tolerance of the electromagnetic shield member 30, particularly the shield ring portion 21. The manufacturing tolerances of the dielectric substrate 20A and the electromagnetic shield member 30 can be reduced as a result. Since the columnar conductor portions 21a to 21g are provided in the shield ring portion 21, when the electromagnetic shield member 30 is mounted on the dielectric substrate 20A, the electromagnetic shield member 30 is positioned by the columnar conductor portions 21a to 21g. The electromagnetic shield member 30 can be easily fixed with solder S (see FIG. 1), conductive adhesive, or the like.

Therefore, according to the above-described electromagnetic shield structure S ₁ , it is easy to reduce the manufacturing cost of a device that requires an electromagnetic shield. Further, since each high frequency functional component MC, MC is mounted on the lower surface of the dielectric substrate 20A and electromagnetically shielded, the upper surface of the dielectric substrate 20A is large even at a position above the high frequency functional component MC, MC. Type capacitor C (see FIGS. 1 and 3), a control digital / analog circuit, and the like can be mounted, and it is easy to increase the mounting density of electronic components and downsize the dielectric substrate 20A. .

Embodiment 2. FIG.
FIG. 5 is a cross-sectional view schematically showing another example of the electromagnetic shield structure. In the electromagnetic shield structure S ₂ shown in the figure, the solid ground vias 18a, 18b high-frequency function on the lower surface of the dielectric substrate 20B provided the parts MC, MC are mounted, these high-frequency functional components MC, MC electromagnetic shield The member 40 is electromagnetically shielded. Among the constituent elements shown in FIG. 5, those common to the constituent elements shown in FIG. 1 are denoted by the same reference numerals as those used in FIG. 1 and description thereof is omitted.

  The solid ground vias appearing in FIG. 5 are the two solid ground vias 18a and 18b. The dielectric substrate 20B includes, for example, 7 as in the dielectric substrate 20A described in the first embodiment. Two solid ground vias are provided at intervals so as to surround each high-frequency functional component MC, MC. The distance D (see FIG. 3) between the solid ground vias adjacent to each other is selected to be less than ½ of the effective wavelength in the substrate of the high-frequency signal used in each high-frequency functional component MC, MC. Further, the lower ends of the individual solid ground vias are covered with the back surface ground pattern. In the figure, two backside ground patterns 19a and 19b appear.

  On the other hand, the electromagnetic shield member 40 surrounds the high-frequency functional parts MC, MC and forms a space Cv that accommodates the high-frequency functional parts MC, MC. The electromagnetic shield member 40 covers the shield ring part 31 and covers the shield ring part 31. It has a lid part 33 that closes the space Cv, and the shield ring part 31 and the lid part 33 are formed of a conductive material such as metal or alloy and are fixed to each other. The upper surface of the shield ring portion 31 is a flat surface. The electromagnetic shield member 40 is made of, for example, solder S formed using a solder paste in a state where the upper surface of the shield ring portion 31 is in contact with the solid ground vias 19a and 19b via the back ground patterns 19a and 19b. Alternatively, it is fixed to the dielectric substrate 20B by a conductive adhesive.

In the electromagnetic shielding structure S ₂ having the above-described configuration, the electromagnetic shielding member 40 provides high electromagnetic shielding properties for the high-frequency functional parts MC and MC for the same reason as in the electromagnetic shielding structure S ₁ described in the first embodiment. Can be easily obtained. Further, the surface accuracy of the dielectric substrate 20B, particularly the surface accuracy of the lower surface, and the manufacturing tolerance of the electromagnetic shield member 40, particularly the manufacturing tolerance of the shield ring portion 31, can be loosened. As a result, the dielectric substrate 20B and the electromagnetic shield member 40 manufacturing costs can be reduced. Therefore, according to the electromagnetic shield structure S ₂ described above, it becomes easy to reduce the manufacturing cost of equipment that requires an electromagnetic shield.

Embodiment 3 FIG.
FIG. 6 is a cross-sectional view schematically showing still another example of the electromagnetic shield structure. In the electromagnetic shield structure S ₃ shown in the figure, the high-frequency functional components MC and MC are mounted on the lower surface of the dielectric substrate 20C having the hollow ground through holes 17a and 17b, and these high-frequency functional components MC and MC are used as the electromagnetic shield member 50. Is electromagnetically shielded. Among the constituent elements of the dielectric substrate 20C, those having the same functions as those of the constituent elements shown in FIG. 1 are designated by the same reference numerals as those used in FIG.

  The hollow ground through holes appearing in FIG. 6 are the two hollow ground through holes 17a and 17b. Each of the dielectric substrates 20C includes, for example, the same as in the dielectric substrate 20A described in the first embodiment. Seven hollow ground through holes are provided at intervals so as to surround the high-frequency functional parts MC and MC. Each hollow ground through hole is formed on the wall surface of the through hole TH provided in the dielectric substrate 20C in the same manner as each hollow ground through hole in the dielectric substrate 20A (see FIG. 1) described in the first embodiment. It consists of the formed cylindrical conductor layer. Further, the distance D (see FIG. 3) between two hollow ground holes adjacent to each other is selected to be less than ½ of the effective wavelength in the substrate of the high-frequency signal used in each of the high-frequency functional parts MC and MC.

  On the other hand, the electromagnetic shield member 50 has a conductive chassis portion 41 that supports the dielectric substrate 20C. The conductive chassis 41 surrounds the high-frequency functional components MC, MC and surrounds the high-frequency functional components MC, MC. A frame-shaped shield ring portion 43 that forms a space Cv (see FIG. 6) to be accommodated is formed by cutting. The conductive chassis portion 41 closes the space Cv. The dielectric substrate 20 </ b> C is screwed to the electromagnetic wave shielding member 50, specifically, to the shield ring portion 43 by conductive screws inserted into individual hollow ground through holes. In FIG. 6, a conductive screw 50a inserted into the hollow ground through hole 17a and a conductive screw 50b inserted into the hollow ground through hole 17b appear. Note that these conductive screws also function as a heat radiator that dissipates heat generated by the operation of the high-frequency functional parts MC and MC to the outside of the space Cv.

In the electromagnetic shielding structure S ₃ having the above-described configuration, the electromagnetic shielding member 50 provides high electromagnetic shielding properties for the high-frequency functional parts MC and MC for the same reason as in the electromagnetic shielding structure S ₁ described in the first embodiment. Can be easily obtained. Further, the surface accuracy of the dielectric substrate 20C, particularly the surface accuracy of the lower surface, and the manufacturing tolerance of the electromagnetic shield member 50, particularly the manufacturing tolerance of the shield ring portion 43, can be loosened. As a result, the dielectric substrate 20C and the electromagnetic shield member 50 manufacturing costs can be reduced. Further, the dielectric substrate high-frequency functional components are mounted so commonly used is fixed to the conductive chassis, by previously forming a shield ring 43 to a conductive chassis 41, as in the electromagnetic shielding structure S ₃ If the electromagnetic shielding member 50 is configured, the number of components can be reduced as compared with the case where a lid for electromagnetic shielding is provided separately from the conductive chassis 41. Therefore, according to the above-described electromagnetic shield structure S ₃ , it is easy to reduce the manufacturing cost of equipment that requires an electromagnetic shield.

  The electromagnetic shield structure of the present invention has been described with reference to the embodiment. However, as described above, the present invention is not limited to the above-described embodiment. For example, the high frequency functional component may be mounted on either the upper surface or the lower surface of the dielectric substrate. Further, the layer configuration on the dielectric substrate, the arrangement pattern of the transmission line, the shape of the hollow ground through hole, and the like can be selected as appropriate. The form of engagement between the hollow ground through hole and the electromagnetic shield member and the form of engagement between the solid ground via and the electromagnetic shield member can be selected as appropriate. For example, the upper surface of the shield ring portion can be brought into direct contact with the lower surface of the hollow ground through hole or solid ground via.

A plurality of hollow ground through holes and at least one ground via can be provided in one dielectric substrate. Also in this case, each hollow ground through hole and ground via are each connected to the inner layer ground pattern. Further, the plurality of hollow ground through holes and the at least one ground via are adjacent to each other (close to each other) (hollow ground through holes or ground vias) in a high frequency signal substrate used in a high frequency functional component. It arrange | positions so that it may become less than 1/2 of an effective wavelength. As in the electromagnetic shield structure S ₁ shown in FIG. 1, a plurality of columnar conductor portions project from the upper surface of the shield ring portion constituting the electromagnetic shield member, and one columnar conductor portion is provided in one hollow ground through hole. The electromagnetic shield member is fixed to the dielectric substrate by inserting and fixing with solder or a conductive adhesive. Alternatively, as in the electromagnetic shield structure S ₃ shown in FIG. 6, the dielectric substrate is made into an electromagnetic wave shielding member by the conductive screw inserted into each hollow ground through hole, specifically, the shield ring portion. Screwed on.

  Further, the electromagnetic shield member having the shield ring portion and the lid portion may be produced by separately manufacturing the shield ring portion and the lid portion and then assembling them into a predetermined shape. It may be formed integrally with the lid portion. For example, if a sheet metal is pressed into an electromagnetic shield member having a columnar conductor part, a shield ring part, and a lid part, the manufacturing cost of the electromagnetic shield member is reduced and the shape of the shield ring part is complicated. Becomes easier. If the shape of the shield ring part can be complicated, the shape of the cavity in the electromagnetic shield member can be made to match the arrangement of the high-frequency functional parts, so it is easy to reduce the size of the electromagnetic shield member become. The electromagnetic shield structure of the present invention can be variously modified, modified, combined, etc. other than those described above.

1 is a cross-sectional view schematically showing an electromagnetic shield structure of a first embodiment. It is a side view which shows roughly the columnar conductor part, shield ring part, and cover part which comprise the electromagnetic shielding structure shown in FIG. It is a top view which shows roughly the electromagnetic shielding structure shown in FIG. It is a bottom view which shows roughly the shield ring part which comprises the electromagnetic shielding structure shown in FIG. It is sectional drawing which shows the electromagnetic shielding structure of Embodiment 2 roughly. It is sectional drawing which shows schematically the electromagnetic shielding structure of Embodiment 3.

Explanation of symbols

7a, 7b, 9a-9c Transmission line 11 Inner layer ground pattern 17a-17g Hollow ground through hole 18a, 18b Solid ground via 19a, 19b Backside ground pattern 20A-20C Dielectric substrate 21, 31, 43 Shield ring portion 21a Columnar conductor Part 23, 33 Lid part 30, 40, 50 Electromagnetic shield member 41 Conductive chassis D Distance between adjacent hollow ground through holes TH Through hole

Claims (7)

A dielectric substrate having a transmission line, an inner layer ground pattern paired with the transmission line, and a pseudo coaxial vertical feed line;
A high frequency functional component mounted on the dielectric substrate and connected to the pseudo coaxial vertical feed line;
A plurality of hollow ground through holes formed in the dielectric substrate so as to surround the high frequency functional component and connected to the inner layer ground pattern;
A plurality of columnar conductor portions inserted into each of the plurality of hollow ground through holes, and a frame-shaped shield ring portion in which a space for accommodating the high-frequency functional component is formed;
A lid portion covering the shield ring portion;
The distance between the hollow ground through holes adjacent to each other is less than ½ of the effective wavelength in the substrate of the high frequency signal used in the high frequency functional component.
An electromagnetic shield structure characterized by that.   2. The electromagnetic shield structure according to claim 1, wherein the plurality of columnar conductor portions have a convex portion that presses the inner wall surface of the hollow ground through hole. A dielectric substrate having a transmission line, an inner layer ground pattern paired with the transmission line, and a pseudo coaxial vertical feed line;
A high frequency functional component mounted on the dielectric substrate and connected to the pseudo coaxial vertical feed line;
A plurality of solid ground vias formed on the dielectric substrate so as to surround the high-frequency functional component and connected to the inner layer ground pattern;
A frame-shaped shield ring portion formed in contact with each of the plurality of solid ground vias and having a space for accommodating the high-frequency functional component;
A lid portion covering the shield ring portion;
The distance between the solid ground vias adjacent to each other is less than ½ of the effective wavelength in the substrate of the high-frequency signal used in the high-frequency functional component.
An electromagnetic shield structure characterized by that. A dielectric substrate having a transmission line, an inner layer ground pattern paired with the transmission line, and a pseudo coaxial vertical feed line;
A high frequency functional component mounted on the dielectric substrate and connected to the pseudo coaxial vertical feed line;
A plurality of hollow ground through holes and at least one ground via formed in the dielectric substrate so as to surround the high frequency functional component and connected to the inner layer ground pattern;
A plurality of columnar conductor portions inserted into each of the plurality of hollow ground through holes, and a frame-shaped shield ring portion in which a space for accommodating the high-frequency functional component is formed;
A lid portion covering the shield ring portion;
The distance between adjacent ones of the plurality of hollow ground through holes and the at least one ground via is less than ½ of an effective wavelength in a substrate of a high frequency signal used in the high frequency functional component Arranged so that,
An electromagnetic shield structure characterized by that. A dielectric substrate having a transmission line, an inner layer ground pattern paired with the transmission line, and a pseudo coaxial vertical feed line;
A high frequency functional component mounted on the dielectric substrate and connected to the pseudo coaxial vertical feed line;
A plurality of hollow ground through holes formed in the dielectric substrate so as to surround the high frequency functional component and connected to the inner layer ground pattern;
A conductive chassis portion formed with a frame-shaped shield ring portion formed in contact with each of the plurality of hollow ground through holes and having a space for accommodating the high-frequency functional component;
A plurality of conductive screws inserted into each of the plurality of hollow ground through holes to fix the dielectric substrate to the shield ring portion;
The distance between the hollow ground through holes adjacent to each other is less than ½ of the effective wavelength in the substrate of the high frequency signal used in the high frequency functional component.
An electromagnetic shield structure characterized by that. A dielectric substrate having a transmission line, an inner layer ground pattern paired with the transmission line, and a pseudo coaxial vertical feed line;
A high frequency functional component mounted on the dielectric substrate and connected to the pseudo coaxial vertical feed line;
A plurality of hollow ground through holes and at least one ground via formed in the dielectric substrate so as to surround the high frequency functional component and connected to the inner layer ground pattern;
A conductive chassis portion formed with a frame-shaped shield ring portion formed in contact with each of the plurality of hollow ground through holes and having a space for accommodating the high-frequency functional component;
A plurality of conductive screws inserted into each of the plurality of hollow ground through holes to fix the dielectric substrate to the shield ring portion;
The distance between adjacent ones of the plurality of hollow ground through holes and the at least one ground via is less than ½ of an effective wavelength in a substrate of a high frequency signal used in the high frequency functional component Arranged so that,
An electromagnetic shield structure characterized by that.   The electromagnetic shielding structure according to claim 1, wherein the high-frequency functional component is a resin-sealed product or a metal-sealed product.

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