With the thinning of a portable terminal or the like, further size reduction and height reduction of a radio frequency module mounted in the portable terminal are required. A radio frequency module in the related art is composed of an interposer substrate, a plurality of electronic circuit components mounted on the interposer substrate, and a resin member that seals the electronic circuit components.
A radio frequency module that does not include an interposer is known generally. Since the interposer is not provided, it is possible to achieve the height reduction.
An aspect of the present disclosure provides a radio frequency module comprising: a first component supported by a first surface, the first component extending along a first axis perpendicular to the first surface; a pedestal supported by the first surface, the pedestal extending along the first axis; and a second component supported by the pedestal, the second component extending along the first axis. Along the first axis, the first component is longer than the second component and the pedestal is between the second component and the first surface. A first solder is between the first surface and the first component, a second solder is between the pedestal and the second component, and a third solder is between the first surface and the pedestal. Along a second axis which is parallel to the first surface: a first dimension W1 of the first solder is greater than a second dimension W2 of the second solder, and a third dimension W3 of the third solder is greater than the second dimension W2.
Another aspect of the present disclosure provides a radio frequency module comprising a first component supported by a first surface, the first component extending along a first axis perpendicular to the first surface; a pedestal supported by the first surface, the pedestal extending along the first axis; a second component supported by the pedestal the second component extending along the first axis; and a plurality of first external terminals and a plurality of second external terminals that are supported by the first surface. The first component is connected to the first plurality of external terminals, and the second component is connected to the second plurality of external terminals via wirings extending through the pedestal. Along the first axis, the first component is longer than the second component and the pedestal is between the second component and the first surface. A first solder is between the first surface and the first component, a second solder is between the pedestal and the second component, and a third solder is between the first surface and the pedestal. Along a second axis which is parallel to the first surface: a first dimension W1 of the first solder is greater than a second dimension W2 of the second solder, and a third dimension W3 of the third solder is greater than the second dimension W2.
The first external terminal and the second external terminal can be used as external terminals for being mounted on another substrate or the like. A degree of variation in a size of the terminal may be smaller than in a case where the first external terminal and the second internal terminal are used as external connection terminals. As a result, it is possible to stably mount the radio frequency module on the substrate. In addition, with the configuration in which the temporary substrate is polished or ground, it is possible to achieve the height reduction in the radio frequency module 100.
Sizes of external terminals of the plurality of electronic circuit components constituting the radio frequency module are not the same as each other. For example, the size of the external terminal is different between a radio frequency integrated circuit (RFIC), a duplexer, a filter, a capacitor, an inductor, and the like.
In the radio frequency module disclosed in Patent Document 1, a plurality of components is supported by a support member, and external terminals of the plurality of components are exposed on one surface of the support member. That is, a plurality of external terminals having different sizes are exposed on one surface.
In a case where solder is placed on the external terminals having different sizes and a reflow treatment is performed, a height of a solder bump varies for each external terminal. Therefore, in a case where the radio frequency module is mounted on another substrate, connection failure tends to occur or an implementation state tends to be unstable. An object of the present disclosure is to provide a radio frequency module that is suitable for height reduction and can be stably mounted on a substrate.
A radio frequency module and a manufacturing method thereof according to a first embodiment will be described with reference to
A plurality of first components 30, a second component 40, and a pedestal 50 are covered with and supported by a support member 70 made of a resin. For example, the support member 70 is in contact with surfaces of the first components 30, the second component 40, and the pedestal 50 to support these components. The support member 70 has a first surface 70A and a second surface 70B that face opposite directions and are disposed substantially parallel to each other. A direction in which the first surface 70A and the second surface 70B are separated from each other is defined as a height direction. A direction perpendicular to the first surface 70A can also be referred to as the height direction. Here, the term “perpendicular direction” does not mean a direction that is strictly perpendicular in a geometrical sense, and includes a substantially perpendicular direction.
A plurality of first external terminals 61, a plurality of second external terminals 62, and a plurality of long terminals 68 are exposed on the first surface 70A. The plurality of long terminals 68 are not essential, and the long terminal 68 need not be provided. Exposed surfaces of the plurality of first external terminals 61, the plurality of second external terminals 62, and the plurality of long terminals 68 are substantially flush with the first surface 70A. In other words, the plurality of first external terminals 61, the plurality of second external terminals 62, and the plurality of long terminals 68 are disposed at the same position in the height direction as the first surface 70A. Due to a variation in a manufacturing process, a slight step may occur between the exposed surfaces of the plurality of first external terminals 61, the plurality of second external terminals 62, and the plurality of long terminals 68, and a boundary with the first surface 70A.
Here, the disposition of the first external terminal 61 at the same position in the height direction as the first surface 70A means that the position in the height direction of one of two surfaces of the first external terminal 61 intersecting the height direction is the same as the position in the height direction of the first surface 70A. The same applies to a positional relationship between the second external terminal 62 and the long terminal 68, and the first surface 70A in the height direction. The configuration in which “the positions in the height direction are the same” includes a case where a deviation occurs in the position in the height direction due to a variation within an allowable range in the manufacturing process.
Each first component 30 has a plurality of first internal terminals 31 disposed on a surface facing the same direction as the first surface 70A (hereinafter, may be referred to as a lower surface 30A). The plurality of first internal terminals 31 are connected to the plurality of respective first external terminals 61 with solder members 81 interposed therebetween. A surface of the first component 30 facing a direction opposite to the lower surface 30A (hereinafter, may be referred to as a top surface 30B) is covered with the support member 70.
The pedestal 50 has a lower surface 50A facing the same direction as the first surface 70A, a top surface 50B facing a direction opposite to the lower surface 50A, a plurality of lower surface side internal terminals 51 disposed on the lower surface 50A, a plurality of top surface side internal terminals 52 disposed on the top surface 50B, and a plurality of wirings 53 connecting the lower surface side internal terminals 51 and the top surface side internal terminals 52 to each other. A printed circuit board is used, for example, as the pedestal 50. The plurality of lower surface side internal terminals 51 are connected to the plurality of respective second external terminals 62 with solder members 82 interposed therebetween.
The second component 40 includes a plurality of second internal terminals 41 disposed on a surface facing the same direction as the first surface 70A (hereinafter, may be referred to as a lower surface 40A). The plurality of second internal terminals 41 are connected to the plurality of respective top surface side internal terminals 52 with solder members 85 interposed therebetween, so that the second component 40 is disposed to be superimposed on the pedestal 50 in the height direction and is fixed to the pedestal 50. A surface of the second component 40 facing a direction opposite to the lower surface 40A (hereinafter, may be referred to as a top surface 40B) is covered with the support member 70.
A height-direction dimension of the first component 30 is denoted by h1, a height-direction dimension of the second component 40 is denoted by h2, and a height-direction dimension of the pedestal 50 is denoted by h3. The height-direction dimension h2 of the second component 40 is smaller than the height-direction dimension h1 of the first component 30 having the largest height-direction dimension h1. That is, among the first components 30 other than the first component 30 having the largest height-direction dimension h1, there may be the first component 30 having the height-direction dimension h1 smaller than the height-direction dimension h2 of the second component 40. The height-direction dimension h3 of the pedestal 50 is also smaller than the height-direction dimension h1 of the first component 30 having the largest height-direction dimension h1.
When the first surface 70A is viewed in plan view (hereinafter, may be simply referred to as “in plan view”), the second component 40 is included in the pedestal 50. At least a portion of the second component 40 may be in a positional relationship of overlapping with at least a portion of the pedestal 50. The second component 40 has the plurality of second internal terminals 41. In plan view, the plurality of second internal terminals 41 overlap with the plurality of respective second external terminals 62.
In plan view, a minimum dimension of each of the plurality of first external terminals 61 is denoted by W1, a minimum dimension of each of the plurality of second external terminals 62 is denoted by W2, a minimum dimension of the second internal terminal 41 is denoted by W3, and a minimum dimension of the long terminal 68 is denoted by W4. The term “minimum dimension” is defined as, when a plane figure is interposed in various directions between two parallel lines in contact with the plane figure on both sides, a minimum distance between the two parallel lines. For example, in a case where the plane figure has a square shape, the minimum dimension thereof is equal to a length of one side, and in a case where the plane figure has a rectangular shape, the minimum dimension thereof is equal to a length of the short side. In a case where the plane figure has a circular shape, the minimum dimension thereof is equal to a length of a diameter, and in a case where the plane figure has an elliptical shape, the minimum dimension thereof is equal to a length of a minor axis.
In plan view, a maximum value of the minimum dimension W1 of each of the plurality of first external terminals 61 is larger than a maximum value of the minimum dimension W3 of each of the plurality of second internal terminals 41. Further, a maximum value of the minimum dimension W2 of each of the second external terminals 62 is larger than the maximum value of the minimum dimension W3 of each of the plurality of second internal terminals 41. The maximum value of the minimum dimension W2 of each of the second external terminals 62 is equal to or smaller than the maximum value of the minimum dimension W1 of each of the first external terminals 61. The maximum value of the minimum dimension W4 of the long terminal 68 is equal to or larger than the maximum value of the minimum dimension W2 of the second external terminal 62 and is equal to or smaller than the maximum value of the minimum dimension W1 of the first external terminal 61. That is, the following expression is established. Here, max means a maximum value of a parameter in parentheses.
Next, the minimum dimension in a case where the shape of the first external terminal 61 in plan view is a shape other than the square shape, the circular shape, or the like will be described with reference to
An xy rectangular coordinate system in which a direction in which the two first external terminals 61 are separated from each other is an x direction is defined. An x-direction dimension of each of the first external terminals 61 is denoted by Lx, and a y-direction dimension thereof is denoted by Ly. In the example illustrated in
Next, an antenna module equipped with the radio frequency module according to the first embodiment will be described with reference to
A plurality of antenna elements 91 are disposed on an antenna surface 90B of the antenna substrate 90 opposite to the mounting surface 90A. As the antenna element 91, for example, a patch antenna is used. In
The plurality of antenna elements 91 are connected to the plurality of respective lands 94 with the wirings 92 in the antenna substrate 90 interposed therebetween. That is, each of the plurality of antenna elements 91 are connected to the second component 40.
A radio frequency connector 93 is mounted on the mounting surface 90A of the antenna substrate 90. The radio frequency connector 93 is connected to one first external terminal 61 with the wiring 92 in the antenna substrate 90 interposed therebetween.
Each of the power amplifier 42 and the low noise amplifier 43 includes an active element. For example, the power amplifier 42 includes a transistor 420, and the low noise amplifier 43 includes a transistor 43Q. Heat is generated mainly in the transistor 420 of the power amplifier 42 during the transmission of the radio frequency signal.
In
In addition,
Next, a manufacturing method of the radio frequency module according to the first embodiment will be described with reference to
As illustrated in
As illustrated in
Either the procedure of mounting the pedestal 50 on the temporary substrate 160 or the procedure of fixing the second component 40 to the pedestal 50 may be performed first. In the steps so far, an intermediate product 161 including the temporary substrate 160, the first component 30, the second component 40, and the pedestal 50 is produced.
As illustrated in
As illustrated in
Next, an advantageous effect of the first embodiment will be described with reference to
As illustrated in
As illustrated in
In general, a terminal of a component having a small height-direction dimension has a dimension smaller than a dimension of a terminal of a component having a large height-direction dimension. As illustrated in
In the first embodiment, the first external terminal 61 and the second external terminal 62 are exposed on the first surface 70A, and the maximum value of the minimum dimension W2 of each of the second external terminals 62 is larger than the maximum value of the minimum dimension W3 of each of the second internal terminals 41. Therefore, as compared with a configuration in which the first external terminal 61 and the second internal terminal 41 are exposed on the first surface 70A, the degree of variation in the minimum dimension of each of the plurality of terminals exposed on the first surface 70A is reduced. That is, the pedestal 50 has a function of increasing the dimension of the second external terminal 62 for connecting the second component 40 to an external substrate or the like to be larger than the dimension of the second internal terminal 41, to approach the dimension of the first external terminal 61.
In a case where the degree of variation in the minimum dimension of each of a plurality of terminals including the first external terminals 61 and the second external terminals 62 is reduced, the degree of variation in the height of the solder applied onto the first external terminal 61 and the second external terminal 62 is also reduced. As a result, it is possible to easily and stably mount the radio frequency module according to the first embodiment on another substrate, such as the antenna substrate 90 (
In a case where the minimum dimension W2 of each of the second external terminals 62 is increased, and a difference from the minimum dimension W3 of each of the second internal terminals 41 is too large, a degree of discontinuity of a characteristic impedance of a feed line from the second internal terminal 41 to the antenna element 91 (
In a case where a difference between the maximum value and a minimum value of the minimum dimension of each of the plurality of terminals including the first external terminals 61 and the second external terminals 62 is too large, it is difficult to stably mount the radio frequency module 100 on another substrate. In order to maintain the advantageous effect in that the radio frequency module 100 can be stably mounted on another substrate, it is preferable that the difference between the maximum value and the minimum value of the minimum dimension of each of the plurality of terminals including the first external terminals 61 and the second external terminals 62 is smaller than a difference between a maximum value and a minimum value of a minimum dimension of each of a plurality of terminals including the first external terminals 61 and the second internal terminals 41.
Further, in order to suppress the attenuation of the advantageous effect in that the radio frequency module 100 can be stably mounted on another substrate, it is preferable to adopt a configuration in which the maximum value of the minimum dimension W4 of each of the plurality of long terminals 68 is equal to or larger than the maximum value of the minimum dimension W2 of each of the second external terminals 62 and is equal to or smaller than the maximum value of the minimum dimension W1 of each of the plurality of first external terminals 61.
The height-direction dimension h2 of the second component 40 included in the radio frequency module 100 according to the first embodiment is smaller than the height-direction dimension h1 of the first component 30. Since the second component 40 having a relatively small height-direction dimension is disposed to be superimposed on the pedestal 50, the top surface 40B of the second component 40 is close to the second surface 70B of the support member 70. Therefore, a thermal resistance of a heat transfer path from the second component 40 to the second surface 70B of the support member 70 is reduced. As a result, the heat radiation from the second component 40 can be enhanced. In particular, in a case where the second component 40 includes the active element such as the transistor 420 (see
Further, in the first embodiment, the first component 30 is connected to the first external terminal 61 without the interposer or the like interposed therebetween. Therefore, it is possible to achieve the height reduction of the radio frequency module 100 as compared with a configuration including the interposer or the like. In a case where the height-direction dimension h3 of the pedestal 50 is too large, the effect of the height reduction is reduced. In order to maintain the advantageous effect in that the height reduction is achieved, it is preferable that the height-direction dimension h3 of the pedestal 50 is equal to or smaller than the height-direction dimension h1 of the first component 30 having the largest height-direction dimension h1. Further, it is preferable that a sum of the height-direction dimension h3 of the pedestal 50 and the height-direction dimension h2 of the second component 40 is 1.5 times or less the height-direction dimension h1 of the first component 30 having the largest height-direction dimension h1.
Next, another manufacturing method of the radio frequency module 100 according to the first embodiment will be described with reference to
As illustrated in
As illustrated in
As illustrated in
As illustrated in
As illustrated in
The radio frequency module 100 manufactured by the present manufacturing method according to the embodiment does not include the lower surface side internal terminal 51 that is disposed on the pedestal 50 of the radio frequency module 100 illustrated in
Next, a radio frequency module according to a modification example of the first embodiment will be described with reference to
Next, a radio frequency module according to another modification example of the first embodiment will be described with reference to
In the present modification example, the first component 30 and the second component 40 included in the radio frequency module 100 can be connected to each other in the radio frequency module 100. Therefore, the number of wirings in the mounting substrate on which the radio frequency module 100 is mounted can be reduced.
Next, a radio frequency module according to still another modification example of the first embodiment will be described with reference to
In the first embodiment (
The structure of the radio frequency module 100 according to the present modification example is produced by, for example, exposing, in the step of polishing or grinding the temporary substrate 160 illustrated in
In the present modification example, further height reduction of the radio frequency module 100 can be achieved. In the step illustrated in
Next, a radio frequency module according to still another modification example of the first embodiment will be described with reference to
In the first embodiment (
By exposing the top surface 40B of the second component 40 from the support member 70, the heat radiation from the second component 40 can be further enhanced. In order to adopt this structure, the height-direction dimension of the pedestal 50 may be set such that the height from the first surface 70A to the top surface 40B of the second component 40 and the height to the exposed top surface 30B of the first component 30 are equal to each other.
Next, a radio frequency module according to a second embodiment will be described with reference to
The antenna component 110 further includes a plurality of antenna terminals 112 disposed on a surface facing the same direction as the direction in which the first surface 70A faces. The plurality of antenna terminals 112 are connected to the plurality of respective radiating elements 111 via the feed lines 113 interposed therebetween. A plurality of third external terminals 63 are exposed on the first surface 70A in addition to the first external terminal 61 and the second external terminal 62. That is, the third external terminal 63 is disposed at the same position in the height direction as the first external terminal 61 and the second external terminal 62.
The plurality of antenna terminals 112 are connected to the plurality of respective third external terminals 63 with the solder members 83 interposed therebetween. A surface of the antenna component 110 facing a direction opposite to the direction in which the first surface 70A faces (hereinafter, may be referred to as a top surface 110B) is flush with the second surface 70B of the support member 70 and is exposed from the support member 70.
The second component 40 is, for example, a radio frequency integrated circuit (RFIC), and the second component 40 is connected to the radiating element 111 with the second external terminal 62, the wiring on the mounting substrate, the third external terminal 63, the solder member 83, the antenna terminal 112, and the feed line 113 interposed therebetween. As illustrated in
The radio frequency signal is supplied from the second component 40 to each of the plurality of radiating elements 111, and a radio wave is emitted from each of the radiating elements 111. A boresight of the radiating element 111 faces the direction opposite to the direction in which the first surface 70A faces. That is, the boresight of the radiating element 111 faces a direction opposite to a direction of a boresight of the antenna element 91 of the antenna module illustrated in
Next, an advantageous effect of the second embodiment will be described.
In the second embodiment, as in the first embodiment, the radio frequency module 100 can be stably mounted on the mounting substrate, and the height reduction of the radio frequency module 100 can be achieved. Further, in the second embodiment, the radio waves can be radiated in a direction opposite to the direction in which the first surface 70A of the support member 70 faces. That is, the radio waves can be radiated in a direction in which the component mounting surface of the mounting substrate on which the radio frequency module 100 is mounted faces.
Next, a modification example of the second embodiment will be described. The radio frequency module 100 according to the second embodiment may be mounted on the antenna substrate 90 illustrated in
Next, a radio frequency module according to a third embodiment will be described with reference to
For example, each of the radiating element 111B and the ground plane 114B is configured of a metal pattern perpendicular to the first surface 70A. The radiating element 111B and the ground plane 114B constitute the patch antenna. The antenna component 110 having such a structure can be produced by using, for example, a 3D printer.
Next, an advantageous effect of the third embodiment will be described. In the third embodiment, as in the second embodiment, the radio frequency module 100 can be stably mounted on the mounting substrate, and the height reduction of the radio frequency module 100 can be achieved. Further, in the third embodiment, the radio waves can be radiated in the direction opposite to the direction in which the first surface 70A faces and the direction parallel to the first surface 70A.
Next, a radio frequency module according to a modification example of the third embodiment will be described.
The radio frequency module 100 according to the third embodiment includes one lateral radiating element 111B, but a plurality of lateral radiating elements 111B may be arranged in a direction parallel to the first surface 70A to constitute an antenna array. In addition, the plurality of lateral radiating elements 111B may be disposed, and the directions of the boresights of the plurality of respective radiating elements 111B may be directed in a plurality of directions parallel to the first surface 70A.
Next, a radio frequency module according to a fourth embodiment will be described with reference to
For example, in plan view, at least one shield functional component 30S is disposed between the antenna component 110 and the second component 40. The second component 40 is not disposed between the antenna component 110 and the shield functional component 30S. As illustrated in
A top surface 133B of the internal support member 133, which faces a direction opposite to a direction in which the second surface 133A faces, and a side surface 133C connecting the second surface 133A and the top surface 133B to each other are covered with a metal film 32. The metal film 32 is covered with the support member 70 (
At least one of the first internal terminals 31 is exposed on the side surface 133C of the internal support member 133 and is connected to the metal film 32. The metal film 32 is connected to the first external terminal 61 (see
As the shield functional component 30S, in addition to the component having the structure illustrated in
Next, an advantageous effect of the fourth embodiment will be described.
In the fourth embodiment, as in the third embodiment, the radio frequency module 100 can be stably mounted on the mounting substrate, and the height reduction of the radio frequency module 100 can be achieved. Further, the metal film 32 of the shield functional component 30S functions as an electromagnetic shield film. That is, the shield functional component 30S functions as a reflector that reflects the radio waves radiated from the antenna component 110. Therefore, it is possible to improve the radiation characteristics of the radiating elements 111A and 111B of the antenna component 110 in the boresight direction. Further, the isolation between the antenna component 110 and other components in the radio frequency module 100 can be enhanced.
Next, a radio frequency module according to a modification example of the fourth embodiment will be described.
In the fourth embodiment (
Each of the above-described embodiments is merely an example, and it is needless to say that the configurations illustrated in different embodiments can be partially replaced or combined with each other. The same actions and effects of the same configurations in a plurality of embodiments are not sequentially referred to for each embodiment. Further, the present disclosure is not limited to the above-described embodiments. For example, it is obvious to a person skilled in the art that various modifications, improvements, combinations, and the like can be made.
Number | Date | Country | Kind |
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2022-057917 | Mar 2022 | JP | national |
The present application is a continuation application of PCT International Application No. PCT/JP2023/008087 filed on Mar. 3, 2023, designating the United States of America, which is based on and claims priority to Japanese patent application JP 2022-057917, filed Mar. 31, 2022. The entire disclosures of the above-identified applications, including the specifications, the drawings, and the claims are incorporated herein by reference in their entirety.
Number | Date | Country | |
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Parent | PCT/JP2023/008087 | Mar 2023 | WO |
Child | 18896937 | US |