BACKGROUND OF THE DISCLOSURE

Field of the Disclosure

The present disclosure relates to a high-frequency module including a sealing resin layer covering a plurality of components mounted on a wiring substrate and a shield wall for preventing mutual interference of noise between the components.

Description of the Related Art

A high-frequency module implemented in a mobile terminal device may include a shield layer for blocking electromagnetic waves. In one example of that type of high-frequency module, the shield layer may cover the surface of mold resin with which components mounted on a wiring substrate are covered.

Such a shield layer is disposed to block noise from the outside. If a plurality of components are mounted on the wiring substrate, there is a problem that noise arising from a component interferes with another component among the plurality of components. Therefore, in addition to the shield layer for noise from the outside, a shield wall for mutually blocking noise between the mounted components may be disposed. The shield wall may be formed by, for example, forming a groove in a resin layer by laser processing and filling the groove with a conductor, such as conductive paste. In that case, the laser light used in forming the groove may affect the wiring substrate, and it may cause a crack in the wiring substrate and may damage the wiring. To avoid that situation, a high-frequency module including a shield between components and capable of minimizing damage to a wiring substrate has been proposed.

One such example is described in Patent Document 1 and illustrated as a high-frequency module100inFIG. 17. In the high-frequency module100, a plurality of electronic components102aand102bare mounted on an upper surface101aof a circuit substrate101, and the electronic components102aand102bare both sealed with a resin section103. The resin section103has a groove104between both the electronic components102aand102b. In the groove104, an exposed section106where a portion of a metal piece105is not covered with the resin section103and is exposed is present. The exposed section106and a shield conductor107formed on the surface of the resin section103are connected to each other, and thus the metal piece105functions as a shield wall between both the electronic components102aand102b.Patent Document 1: Japanese Unexamined Patent Application Publication No. 2011-187677 (see paragraphs 0014 to 0021,FIG. 1, and the like)

BRIEF SUMMARY OF THE DISCLOSURE

The high-frequency module100described in Patent Document 1, however, has a structure in which the groove104divides the resin section103so that the resin section103is entirely divided into the region on the electronic component102aside and the region on the electronic component102bside. Therefore, the high-frequency module100has a reduced mechanical strength, and it may be warped by its production process or thermal stress.

The present disclosure is made in consideration of the above problem. It is an object of the present disclosure to provide a high-frequency module having a configuration that includes a groove formed in a sealing resin layer and a shield disposed between components, the high-frequency module capable of having an improved mechanical strength and reducing the occurrence of warpage with continuous shield walls arranged in two spaced grooves and connected by a connecting conductor without entirely dividing the sealing resin layer.

To achieve the above object, a high-frequency module according to the present disclosure includes a wiring substrate, a first component and a second component, a shield member, and a sealing resin layer. The first component and the second component are mounted on a principal surface of the wiring substrate. The shield member is arranged between the first component and the second component. The sealing resin layer is formed on the principal surface of the wiring substrate and seals the first component and the second component. The shield member includes a first shield wall arranged in a first groove formed in the sealing resin layer, a second shield wall arranged in a second groove formed in the sealing resin layer, the second groove spaced from the first groove, and a connecting conductor arranged on the principal surface of the wiring substrate and connecting a first end of the first shield wall and a first end of the second shield wall. The sealing resin layer includes a first region where the first component is sealed with the shield member and a second region where the second component is sealed therewith, and the first region and the second region are contiguous at a location of the connecting conductor.

According to that configuration, because the first groove and the second groove are not in contact with each other, the first region and the second region in the sealing resin layer are not entirely divided. Thus, degradation in mechanical strength caused by dividing the sealing resin layer can be suppressed, and the occurrence of warpage can be reduced.

The connecting conductor may include a pair of leg sections having first ends connected to the principal surface of the wiring substrate and standing on the principal surface and a bridge section bridging second ends of the pair of leg sections. According to that configuration, a metal pin and wire can be used as the connecting conductor.

A third component or a wiring electrode may be arranged between the pair of leg sections in the connecting conductor, and the connecting conductor may straddle the third component or the wiring electrode. According to that configuration, the shield wall between the components can straddle another component or the wiring electrode.

The connecting conductor may be made of a metal block. In that case, the metal block can be used as the connecting conductor.

As seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member may include a bent section, and the connecting conductor may be arranged at the bent section. If the grooves for accommodating the shield walls are formed by, for example, laser processing or the like, when the grooves have the bent section, the laser scanning stops momentarily, and thus the length of the laser radiation time is extended. Accordingly, the energy of the laser light is more strongly exerted on the bent section than the other areas, and under the same laser condition, the damage to the wiring substrate is increased. According to the above-described configuration, where the connecting conductor is arranged on each of the bent sections and the grooves are formed in a zigzag shape, damage to the substrate caused by laser light in forming the grooves can be avoided.

The high-frequency module may further include a first end conductor arranged on an edge of the principal surface of the wiring substrate and connected to a second end of the first shield wall and a second end conductor arranged on the edge of the principal surface of the wiring substrate and connected to a second end of the second shield wall.

For example, if the grooves for accommodating the shield walls are formed by laser processing, it is likely that a crack occurs in particular, in the edge of the wiring substrate. Consequently, according to that configuration, the first and second end conductors are arranged on the edge of the wiring substrate so that the first and second grooves do not reach the edge of the wiring substrate, and thus damage to the wiring substrate can be avoided.

A high-frequency module may include a wiring substrate, a first component and a second component, a shield member, and a sealing resin layer. The first component and the second component may be mounted on a principal surface of the wiring substrate. The shield member may be arranged between the first component and the second component and may surround the first component. The sealing resin layer may be formed on the principal surface of the wiring substrate and may seal the first component and the second component. The shield member may have a rectangular shape as seen from a direction perpendicular to the principal surface of the wiring substrate. The shield member may include four shield walls arranged in four grooves, respectively, the four grooves spaced from each other and formed along sides of the rectangular shape, and four connecting conductors arranged on the principal surface of the wiring substrate at four corner sections of the rectangular shape, respectively. The sealing resin layer may include a first region where the first component is sealed with the shield member and a second region where the second component is sealed therewith, and the first region and the second region may be contiguous at a location of each of the connecting conductors.

According to that configuration, the shield walls surrounding the component and not dividing the resin in the sealing resin layer can be formed.

A high-frequency module may include a wiring substrate, a first component and a second component, a shield member, and a sealing resin layer. The first component and the second component may be mounted on a principal surface of the wiring substrate. The shield member may be arranged between the first component and the second component. The sealing resin layer may be formed on the principal surface of the wiring substrate and may seal the first component and the second component. The shield member may include a shield wall arranged in a groove formed in the sealing resin layer, a third end conductor arranged on an edge of the principal surface of the wiring substrate and connected to a first end of the shield wall, and a fourth end conductor arranged on the edge of the principal surface of the wiring substrate and connected to a second end of the shield wall. The sealing resin layer may include a first region where the first component is sealed with the shield member and a second region where the second component is sealed therewith, and the first region and the second region may be contiguous at a location of each of the third end conductor and the fourth end conductor.

According to that configuration, even with the single shield wall, the shield between the components can be formed without dividing the resin in the sealing resin layer.

According to the present disclosure, the grooves for accommodating the shield walls functioning as the shield between the components are formed without dividing the sealing resin layer, the two shield walls arranged in the two grooves are connected by the connecting conductor, and thus the shield between the components can be disposed while the sealing resin layer is not entirely divided. Therefore, the mechanical strength of the module can be improved without degrading the function of the shield between the components, and this can lead to reduced warpage of the module.

