High-frequency module

Abstract

A high-frequency module (1a) includes a multilayer wiring substrate (2), a plurality of components (3a, 3b) mounted on an upper surface (20a) of the multilayer wiring substrate (2), a sealing resin layer (4) laminated on the upper surface (20a) of the multilayer wiring substrate (2) and sealing the plurality of components (3a, 3b), and a shield (5). The shield (5) is composed of shield walls (5a, 5b) arranged in grooves (12) and (13), respectively, formed between the first component (3a) and the second component (3b) in the sealing resin layer (4) and a connecting conductor (11) coupling both the shield walls (5a, 5b). A first region (40a) and a second region (40b) in the sealing resin layer (4) split by the shield (5) are contiguous at the location of the connecting conductor (11) as seen from a direction perpendicular to the upper surface (20a) of the multilayer wiring substrate (2).

Claims

1. A high-frequency module comprising: a wiring substrate; a first component and a second component mounted on a principal surface of the wiring substrate; a shield member arranged between the first component and the second component; and a sealing resin layer provided on the principal surface of the wiring substrate and sealing the first component and the second component, wherein the shield member includes a first shield wall arranged in a first groove provided in the sealing resin layer, a second shield wall arranged in a second groove provided 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 is divided into a first region and a second region, the first component is sealed with the shield member in the first region, the second component is sealed with the shield member in the second region, and the first region and the second region are contiguous at a location of the connecting conductor, wherein the first shield wall and the second shield wall are spaced and are not in contact with each other.

2. The high-frequency module according to claim 1, wherein the connecting conductor includes a pair of leg sections and a bridge section, the pair of leg sections have first ends connected to the principal surface of the wiring substrate and stand on the principal surface, and the bridge section bridges second ends of the pair of leg sections.

3. The high-frequency module according to claim 2, wherein a third component or a wiring electrode is arranged between the pair of leg sections in the connecting conductor, and the connecting conductor straddles the third component or the wiring electrode.

4. The high-frequency module according to claim 1, wherein the connecting conductor is comprised of a metal block.

5. The high-frequency module according to claim 1, wherein as seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member includes a bent section, and the connecting conductor is arranged at the bent section.

6. The high-frequency module according to claim 1, further comprising: 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.

7. A high-frequency module comprising: a wiring substrate; a first component and a second component mounted on a principal surface of the wiring substrate; a shield member arranged between the first component and the second component and surrounding the first component; and a sealing resin layer provided on the principal surface of the wiring substrate and sealing the first component and the second component, wherein the shield member has a rectangular shape as seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member includes four shield walls arranged in four grooves, respectively, the four grooves spaced from each other and provided 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 is divided into a first region and a second region, the first component is sealed with the shield member in the first region, the second component is sealed with the shield member in the second region, and the first region and the second region are contiguous at a location of each of the connecting conductors, wherein the shield walls are spaced and are not in contact with each other.

8. A high-frequency module comprising: a wiring substrate; a first component and a second component mounted on a principal surface of the wiring substrate; a shield member arranged between the first component and the second component; and a sealing resin layer provided on the principal surface of the wiring substrate and sealing the first component and the second component, wherein the shield member includes a shield wall arranged in a groove provided 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 is divided into a first region and a second region, the first component is sealed with the shield member in the first region, the second component is sealed with the shield member in the second region, and the first region and the second region are integrally connected to each other at a location of each of the third end conductor and the fourth end conductor.

9. The high-frequency module according to claim 2, wherein as seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member includes a bent section, and the connecting conductor is arranged at the bent section.

10. The high-frequency module according to claim 3, wherein as seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member includes a bent section, and the connecting conductor is arranged at the bent section.

11. The high-frequency module according to claim 4, wherein as seen from a direction perpendicular to the principal surface of the wiring substrate, the shield member includes a bent section, and the connecting conductor is arranged at the bent section.

12. The high-frequency module according to claim 2, further comprising: 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.

13. The high-frequency module according to claim 3, further comprising: 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.

14. The high-frequency module according to claim 4, further comprising: 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.

15. The high-frequency module according to claim 5, further comprising: 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.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) FIG. 1 is a cross-sectional view of a high-frequency module according to a first embodiment of the present disclosure taken along line A-A with arrows in FIG. 2.

(2) FIG. 2 is a plan view of the high-frequency module in FIG. 1 in a state where an upper surface of a shield film is removed.

(3) FIGS. 3A and 3B illustrate patterns of the shape of shield walls in FIG. 1.

(4) FIG. 4 illustrates a variation of the high-frequency module in FIG. 1 and is a cross-sectional view taken along line B-B with arrows in FIG. 5.

(5) FIG. 5 is a plan view of the high-frequency module in FIG. 4 in a state where an upper surface of a shield film is removed.

(6) FIG. 6 illustrates another variation of the high-frequency module in FIG. 1 and is a cross-sectional view taken along line C-C with arrows in FIG. 7.

(7) FIG. 7 is a plan view of the high-frequency module in FIG. 6 in a state where an upper surface of a shield film is removed.

(8) FIG. 8 is a cross-sectional view of a high-frequency module according to a second embodiment taken along line D-D with arrows in FIG. 9.

(9) FIG. 9 is a plan view of the high-frequency module in FIG. 8 in a state where an upper surface of a shield film is removed.

(10) FIG. 10 illustrates a variation of the high-frequency module in FIG. 8 and is a cross-sectional view taken along line E-E with arrows in FIG. 11.

(11) FIG. 11 is a plan view of the high-frequency module in FIG. 10 in a state where an upper surface of a shield film is removed.

(12) FIG. 12 is a cross-sectional view of a high-frequency module according to a third embodiment taken along line F-F with arrows in FIG. 13.

(13) FIG. 13 is a plan view of the high-frequency module in FIG. 12 in a state where an upper surface of a shield film is removed.

(14) FIG. 14 is a cross-sectional view of a high-frequency module according to a fourth embodiment taken along line G-G with arrows in FIG. 15.

(15) FIG. 15 is a plan view of the high-frequency module in FIG. 14 in a state where an upper surface of a shield film is removed.

(16) FIG. 16 illustrates a variation of the high-frequency module in FIG. 14.

(17) FIG. 17 is a cross-sectional view of a high-frequency module in related art.

DETAILED DESCRIPTION OF THE DISCLOSURE

First Embodiment

(18) A high-frequency module 1a according to a first embodiment of the present disclosure is described with reference to FIGS. 1 to 3B. FIG. 1 is a cross-sectional view of the high-frequency module 1a, FIG. 2 is a plan view of the high-frequency module 1a in a state where an upper surface of a shield film 6 and a sealing resin layer 4 are removed, and FIGS. 3A and 3B illustrate patterns of the shape of shield walls in the high-frequency module 1a in FIG. 1.

(19) As illustrated in FIGS. 1 and 2, the high-frequency module 1a according to the present embodiment includes a multilayer wiring substrate 2 (corresponding to “wiring substrate” in the present disclosure), a first component 3a and a second component 3b mounted on an upper surface 20a of the multilayer wiring substrate 2, the sealing resin layer 4 laminated on the upper surface 20a of the multilayer wiring substrate 2, the shield film 6 covering the surface of the sealing resin layer 4, and a shield 5 (corresponding to “shield member” in the present disclosure) disposed in the sealing resin layer 4. The high-frequency module 1a may be implemented on, for example, a mother board or the like of an electronic apparatus that uses high-frequency signals.

(20) The multilayer wiring substrate 2 may be a laminate of a plurality of insulating layers 2a to 2d made of, for example, a low-temperature co-fired ceramic material or glass epoxy resin. Mounting electrodes (not illustrated) for mounting the components 3a and 3b and a surface-layer electrode 7 connected to two shield walls 5a and 5b constituting the shield 5, as described below, are formed on the upper surface 20a of the multilayer wiring substrate 2 (corresponding to “principal surface of the wiring substrate in the present disclosure), and a plurality of outer electrodes 8 for outer connection are formed on a lower surface 20b. In the present embodiment, various inner wiring electrodes 9 are arranged between neighboring ones of the insulating layers 2a to 2d. A plurality of via conductors 10 for connecting the inner wiring electrodes 9 formed on different ones of the insulating layers 2a to 2d are formed inside the multilayer wiring substrate 2. The surface-layer electrode 7 is connected to the inner wiring electrode 9 functioning as a ground electrode.

(21) Each of the mounting electrodes, surface-layer electrode 7, outer electrodes 8, and inner wiring electrodes 9 is made of a metal that can be typically used as a wiring electrode, such as copper, silver, or aluminums. Each of the via conductors 10 is made of a metal, such as silver or copper. Each of the mounting electrodes, surface-layer electrode 7, and outer electrodes 8 may be coated with nickel and gold plating.

(22) The first component 3a is configured as a semiconductor device made of a semiconductor, such as silicon or gallium arsenide, or a chip component, such as a chip inductor, a chip capacitor, or a chip resistor. When seen from a direction perpendicular to the upper surface 20a of the multilayer wiring substrate 2, the first component 3a is mounted in a position in a first region 40a in the sealing resin layer 4. The second component 3b is configured as a semiconductor device made of a semiconductor, such as silicon or gallium arsenide, or a chip component, such as a chip inductor, a chip capacitor, or a chip resistor. When seen from the direction perpendicular to the upper surface 20a of the multilayer wiring substrate 2, the second component 3b is mounted in a position in a second region 40b in the sealing resin layer 4.

(23) The sealing resin layer 4 covers the upper surface 20a of the multilayer wiring substrate 2 and the components 3a and 3b and is laminated on the multilayer wiring substrate 2. The sealing resin layer 4 can be made of a resin that can be typically used as a sealing resin, such as an epoxy resin.

(24) The shield film 6 is used for blocking noise from the outside to the various inner wiring electrodes 9 inside the multilayer wiring substrate 2 and the components 3a and 3b and covers an upper surface 4a and side surfaces 4c of the sealing resin layer 4 and side surfaces 20c of the multilayer wiring substrate 2. The shield film 6 can be formed as a multilayer structure including a close contact film laminated on the surface of the sealing resin layer 4, a conductive film laminated on the close contact film, and a protective film laminated on the conductive film.

(25) The close contact film is disposed to enhance the strength of contact between the conductive film and the sealing resin layer 4 and can be made of, for example, a metal, such as stainless steel. The conductive film is a layer that virtually serves the shielding function of the shield film 6 and can be made of, for example, a metal selected among copper, silver, and aluminum. The protective film is disposed to prevent the conductive film from corrosion and scratches and can be made of, for example, stainless steel.

(26) The shield 5 is arranged between the first component 3a and the second component 3b in the sealing resin layer 4 and is composed of two shield walls of the first shield wall 5a and the second shield wall 5b and a connecting conductor 11 connecting both the shield walls 5a and 5b. Specifically, as illustrated in FIG. 2, when seen from the direction perpendicular to the upper surface 20a of the multilayer wiring substrate 2, a first groove 12 and a second groove 13 are formed so as to partition the sealing resin layer 4 into two regions of the first region 40a and the second region 40b. By filling both the grooves 12 and 13 with conductive paste predominantly composed of a material, such as copper or silver, the shield walls 5a and 5b are formed. Both the grooves 12 and 13 are spaced so that they are not in contact with each other. Accordingly, both the shield walls 5a and 5b are also spaced so that they are not in contact with each other. The connecting conductor 11 is arranged so as to connect both the shield walls 5a and 5b, and the first shield wall 5a, the connecting conductor 11, and the second shield wall 5b constitute the continuous shield 5. Thus, the shield 5 separates the sealing resin layer 4 into the first region 40a and the second region 40b. The connecting conductor 11 is made of a metal in the shape of a block having a height smaller than that of the sealing resin layer 4, and the first region 40a and the second region 40b in the sealing resin layer 4 are contiguous above the connecting conductor 11. Here, the connecting conductor 11 can be fixed to a land electrode formed on the upper surface 20a of the multilayer wiring substrate 2, that land electrode can be electrically connected to a ground terminal, and thus the shield 5 can be connected to the ground. In that case, it is not necessary to connect the shield 5 and the inner electrodes exposed to the side surfaces 20c of the multilayer wiring substrate 2.

(27) In the present embodiment, both the grooves 12 and 13 are formed by laser processing. During that processing, the surface-layer electrode 7 also performs the function of protecting the upper surface 20a of the multilayer wiring substrate 2 from damage caused by the laser. As illustrated in FIG. 3A, each of both the grooves 12 and 13 may be formed with a depth at which it does not reach the upper surface 20a of the multilayer wiring substrate 2. As illustrated in FIG. 3B, each of both the grooves 12 and 13 may be formed with a depth at which it reaches the upper surface 20a of the multilayer wiring substrate 2 in some areas and does not reach the upper surface 20a of the multilayer wiring substrate 2 in the other areas. In both the cases illustrated in FIGS. 3A and 3B, the first shield wall 5a and the second shield wall 5b are connected by the connecting conductor 11. The first region 40a and the second region 40b in the sealing resin layer 4 are contiguous above the connecting conductor 11. As illustrated in FIGS. 3A and 3B, when each of both the grooves 12 and 13 has a depth at which it does not reach the upper surface 20a, the surface-layer electrode 7 may not be formed.

(28) Consequently, according to the above-described embodiment, because both the grooves 12 and 13 are not in contact with each other, both the shield walls 5a and 5b are also not in contact with each other, and the sealing resin layer 4 is not entirely divided. Thus, cracks of the sealing resin layer 4, degradation in mechanical strength of the high-frequency module 1a, and the occurrence of warpage thereof can be reduced. Because both the shield walls 5a and 5b are connected by the connecting conductor 11, they function as a single continuous shield as the shield arranged between the components. Each of both the grooves 12 and 13 has a depth at which it does not reach the upper surface 20a of the multilayer wiring substrate 2, and thus damage to the upper surface 20a of the multilayer wiring substrate 2 and damage to components adjacent to both the grooves 12 and 13 can be reduced. In addition, the top surface of the high-frequency module can easily provide a printable area.

(29) (Variations of High-Frequency Module 1a)

(30) In the above-described embodiment, the connecting conductor 11 is made of a metal in the shape of a block. In another example, as in a module 1b illustrated in FIGS. 4 and 5, a connecting conductor 11a may be made of a U-shaped metal pin or wire including a pair of leg sections 14a and a bridge section 14b bridging both the leg sections 14a. Both the leg sections 14a are connected to the surface-layer electrode 7, and the connecting conductor 11a stands on the upper surface 20a of the multilayer wiring substrate 2. In that configuration, because the connecting conductor 11a has the U shape, a wiring electrode can be arranged between both the leg sections 14a in the connecting conductor 11a.

(31) In a module 1c illustrated in FIGS. 6 and 7, a connecting conductor 11b is the one in which a plurality of U-shaped metal pins or wires each including a pair of leg sections (not illustrated) and a bridge section 14b connecting both the leg sections are coupled. In the module 1b illustrated in FIGS. 4 and 5, the bridge section or a portion of the bridge section and the leg sections is connected to the first shield wall 5a and the second shield wall 5b. In the module 1c, neither of the leg sections is connected to the shield wall 5a or 5b, and the bridge section is connected to both the shield walls 5a and 5b. When seen from the direction perpendicular to the upper surface 20a of the multilayer wiring substrate 2, the connecting conductor 11b is arranged in a position where the bridge sections 14b are substantially orthogonal to both the shield walls 5a and 5b. In that configuration, a third component 3c can be arranged between both the leg sections in the connecting conductor 11b.

Second Embodiment

(32) A high-frequency module 1d according to a second embodiment of the present disclosure is described with reference to FIGS. 8 and 9. FIG. 8 is a cross-sectional view of the high-frequency module 1d. FIG. 9 is a plan view of the high-frequency module 1d in a state where the upper surface of the shield film 6 and the sealing resin layer 4 are removed.

(33) The high-frequency module 1d according to the present embodiment differs from the high-frequency module 1a according to the first embodiment described with reference to FIGS. 1 to 3B in that the shield 5 has bent sections, as illustrated in FIGS. 8 and 9. Since the other configurations are the same as those of the high-frequency module 1a according to the first embodiment, the same reference numerals are used therein, and the description is omitted.

(34) In the present embodiment, a shield 50 is composed of three shield walls 50a, 50b, and 50c and two connecting conductors 11c, and it has a zigzag shape including bent sections 5a1 and 5b1 as seen from the direction perpendicular to the upper surface 20a of the multilayer wiring substrate 2. Each of grooves 12a, 13a, and 15 for accommodating the shield walls 50a, 50b, and 50c, respectively, has a linear shape. At the bent section 5a1, the shield walls 50a and 50c are connected by one of the connecting conductors 11c, and at the bent section 5b1, the shield walls 50b and 50c are connected by the other connecting conductor 11c.

(35) In forming the grooves for accommodating the shield walls by laser processing, because energy of the laser light is more strongly exerted on the bent sections 5a1 and 5b1 than on the other sections, the grooves are deeper under the same laser condition. Therefore, damage is likely to occur in the upper surface 20a of the multilayer wiring substrate 2 at the bent sections 5a1 and 5b1. In this configuration, however, the connecting conductors 11c are disposed at the bent sections 5a1 and 5b1, and thus the laser light is not exerted on the bent sections for a long time. Therefore, no damage occurs in the upper surface 20a of the multilayer wiring substrate 2, and the shield 50 can be formed without narrowing the region where components can be arranged.

(36) (Variation of High-Frequency Module 1d)

(37) In the above-described embodiment, the three shield walls 50a, 50b, and 50c and the two connecting conductors 11c constitute the shield 50. As in a high-frequency module 1e illustrated in FIGS. 10 and 11, a shield 51 including the bent sections 5a1 and 5b1 may be composed of the two grooves 12a and 13a and a single connecting conductor 11d. The shield 51 including the bent sections 5a1 and 5b1 can be formed by arranging the connecting conductor 11d in the position corresponding to the shield wall 50c in the high-frequency module 1d illustrated in FIGS. 8 and 9, instead of the groove and shield wall.

Third Embodiment

(38) A high-frequency module if according to a third embodiment of the present disclosure is described with reference to FIGS. 12 and 13. FIG. 12 is a cross-sectional view of the high-frequency module 1f. FIG. 13 is a plan view of the high-frequency module if in a state where the upper surface of the shield film 6 and the sealing resin layer 4 are removed.

(39) The high-frequency module if according to the present embodiment differs from the high-frequency module 1a according to the first embodiment described with reference to FIGS. 1 to 3B in that a shield 52 surrounds the first component 3a, as illustrated in FIGS. 12 and 13. Since the other configurations are the same as those of the high-frequency module 1a according to the first embodiment, the same reference numerals are used therein, and the description is omitted.

(40) In the present embodiment, the shield 52 is composed of four shield walls 52a to 52d and four connecting conductors 11e and has a rectangular shape. The first component 3a is arranged inside the rectangular shield 52. Four grooves 16a to 16d disposed in the sealing resin layer 4 are spaced away from each other so as not to be in contact with each other and are formed along the sides of the rectangular shape. By filling the grooves 16a to 16d with conductive paste predominantly composed of copper, silver, or the like, the shield walls 52a to 52d are arranged. The connecting conductors 11e are arranged at the four corner sections of the rectangular shape, and the rectangular shield 52 is formed.

(41) According to that configuration, the shield arranged between components having various shapes can be formed by utilizing the combination of the plurality of shield walls and the plurality of connecting conductors.

Fourth Embodiment

(42) A high-frequency module 1g according to a fourth embodiment of the present disclosure is described with reference to FIGS. 14 and 15. FIG. 14 is a cross-sectional view of the high-frequency module 1g. FIG. 15 is a plan view of the high-frequency module 1g in a state where the upper surface of the shield film 6 and the sealing resin layer 4 are removed.

(43) The high-frequency module 1g according to the present embodiment differs from the high-frequency module 1a according to the first embodiment described with reference to FIGS. 1 to 3B in that a shield 53 is composed of a single shield wall and two end conductors 17a and 17b formed on an edge of the upper surface 20a of the multilayer wiring substrate 2, as illustrated in FIGS. 14 and 15. Since the other configurations are the same as those of the high-frequency module 1a according to the first embodiment, the same reference numerals are used therein, and the description is omitted.

(44) In the present embodiment, the shield 53 is composed of a shield wall 53a and the end conductors 17a and 17b (corresponding to “third end conductor” and “fourth end conductor” in the present disclosure) formed on the edge of the upper surface 20a of the multilayer wiring substrate 2. The shield wall 53a is formed by filling a groove 18 formed in the sealing resin layer 4 with conductive paste predominantly composed of copper, silver, or the like.

(45) According to the above-described embodiment, even with the single shield wall 53a, because it is connected to the two end conductors 17a and 17b arranged on the edge of the upper surface 20a of the multilayer wiring substrate 2, the shield 53 between the first component 3a and the second component 3b can be configured without entirely dividing the sealing resin layer 4.

(46) (Variation of High-Frequency Module 1g)

(47) As in a high-frequency module 1h illustrated in FIG. 16, a shield 54 may be composed of two or more shield walls, one or more connecting conductors, and two end conductors. The shield 54 is composed of three shield walls 54a, 54b, and 54c arranged by filling the three grooves 12a, 13a, and 15 with conductive paste predominantly composed of copper, silver, or the like, the two connecting conductors 11c, and two end conductors 19a and 19b (corresponding to “first end conductor” and “second end conductor” in the present disclosure).

(48) In that configuration, because the end conductors 19a and 19b can be arranged on the edge of the upper surface 20a of the multilayer wiring substrate 2, the edge being more susceptible to laser than the other sections in forming the grooves 12a and 13a, damage to the multilayer wiring substrate 2 can be avoided.

(49) The present disclosure is not limited to the above-described embodiments, and various changes other than the above-described ones can be made as long as they do not depart from its spirit. For example, the configurations in the above-described embodiments and variations may be combined.

(50) The term “on” used herein includes when elements are in direct contact with each other and when another element is present between elements.

(51) The present disclosure is applicable to various high-frequency modules including a sealing resin layer covering components mounted on a wiring substrate and a shield wall for preventing mutual interference of noise between the components. 1a to 1h high-frequency module 2 multilayer wiring substrate (wiring substrate) 3a, 3b component (first component, second component) 3c third component 4 sealing resin layer 5, 50 to 54 shield (shield member) 5a, 5b, 50a to 50c, 52a to 52d, 53a, 54a to 54c shield wall 5a1, 5b1 bent section 11, 11a to 11e connecting conductor 12, 13, 12a, 13a, 15, 16a to 16d groove 17a, 17b end conductor (third end conductor, fourth end conductor) 19a, 19b end conductor (first end conductor, second end conductor) 40a first region 40b second region