High-frequency package

Abstract

To obtain a high-frequency package that can improve high-frequency characteristics and cooling performance. [Solution] The high-frequency package 1 comprises a box-shaped cooling section 2 without a lid, a package device 3 housed in the cooling section 2, and a multilayer resin substrate 4 covering the space of the cooling section 2. The package device 3 comprises a carrier 32, a monolithic microwave integrated circuit 33, a sealing lid 31, a multilayer ceramic substrate 34, a connection pad 35 for high-frequency signals, and connection pads for DC power and control signals. The multilayer resin substrate 4 has strip lines for high-frequency signals in its inner layer, and on the back surface of the substrate, it has a connection pad 44 for high-frequency signals, connection pads for DC power and control signals, and a plurality of spring terminals 46. The package device 3 is fixed to the cooling section 2 by screws. Each of the plurality of spring terminals 46 is connected to the corresponding pad on the package device 3.

Description

Technical Field

[0001] The present disclosure relates to a high-frequency package used for transmitting and receiving high-frequency signals.

Background Art

[0002] Patent Document 1 discloses a microwave device which is a high-frequency package in which a signal surface and a heat dissipation surface are separated. In a conventional microwave device, a conductive copper pillar is erected on a pad portion of a monolithic microwave integrated circuit, and the monolithic microwave integrated circuit is flip-chip mounted on a package substrate, whereby the monolithic microwave integrated circuit is electrically connected to the package substrate. A heat spreader is attached to the surface opposite to the mounting surface of the monolithic microwave integrated circuit, thereby securing a heat dissipation path, and thereby realizing a separation structure between the signal surface and the heat dissipation surface. A conventional microwave device is molded with resin, and a conductive shield is provided on the outside of the resin mold, thereby suppressing radiation.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Conventional microwave devices have a problem that their high-frequency performance deteriorates because they are provided with a resin mold. Conventionally, when mounting a microwave device on a resin substrate and then attaching it to a cooling plate, it is necessary to sandwich a heat-conductive heat-dissipating material. Due to the problem of the thermal conductivity of the heat-conductive heat-dissipating material, conventional microwave devices also have a problem that their cooling performance deteriorates.

[0005] This disclosure has been made in view of the above, and aims to provide a high-frequency package that can improve high-frequency characteristics and cooling performance. [Means for solving the problem]

[0006] To solve the above-mentioned problems and achieve the objective, the high-frequency package according to this disclosure comprises a box-shaped cooling section without a lid, a package device housed in the cooling section, and a multilayer resin substrate covering the space of the cooling section. The package device comprises a carrier, a monolithic microwave integrated circuit mounted on the carrier, a sealing lid covering the monolithic microwave integrated circuit, a multilayer ceramic substrate connected to the monolithic microwave integrated circuit, connection pads for high-frequency signals connected to the multilayer ceramic substrate, and connection pads for DC power and control signals connected to the multilayer ceramic substrate. The multilayer resin substrate has strip lines for high-frequency signals in its inner layer, and on the back surface of the substrate, it has connection pads for high-frequency signals, connection pads for DC power and control signals, and a plurality of spring terminals. Each of the plurality of spring terminals is connected to either a connection pad for high-frequency signals or a connection pad for DC power and control signals. The package device is fixed to the cooling section by screws. Each of the plurality of spring terminals is connected to the corresponding pad of the package device. [Effects of the Invention]

[0007] The high-frequency package described herein has the effect of improving high-frequency characteristics and cooling performance. [Brief explanation of the drawing]

[0008] [Figure 1] A first plan view schematically showing the structure of the high-frequency package according to Embodiment 1. [Figure 2] A first cross-sectional view schematically showing the structure of the high-frequency package according to Embodiment 1. [Figure 3] A second plan view schematically showing the structure of the high-frequency package according to Embodiment 1. [Figure 4]A second cross-sectional view schematically showing the structure of the high-frequency package according to Embodiment 1. [Figure 5] A schematic plan view showing the structure of the package device of the high-frequency package according to Embodiment 1. [Figure 6] A schematic cross-sectional view showing the structure of the package device of the high-frequency package according to Embodiment 1. [Figure 7] This figure schematically shows a part of the structure of the multilayer resin substrate of the high-frequency package according to Embodiment 1. [Figure 8] This diagram schematically shows a part of the high-frequency package to explain a part of the connection between the package device and the multilayer resin substrate in the high-frequency package according to Embodiment 1. [Figure 9] Figure 1 schematically shows the structure of the high-frequency package according to Embodiment 2. [Figure 10] Figure 2 schematically shows the structure of the high-frequency package according to Embodiment 2. [Modes for carrying out the invention]

[0009] The high-frequency package according to the embodiment will be described in detail below with reference to the drawings.

[0010] Embodiment 1. Figure 1 is a first plan view schematically showing the structure of the high-frequency package 1 according to Embodiment 1. Figure 2 is a first cross-sectional view schematically showing the structure of the high-frequency package 1 according to Embodiment 1. Figure 2 shows a cross-section of the high-frequency package 1 when cut along the line II-II in Figure 1. The high-frequency package 1 has a box-shaped cooling section 2 without a lid, a package device 3 housed in the cooling section 2, and a multilayer resin substrate 4 covering the space of the cooling section 2. Figure 1 mainly shows the surface layer of the multilayer resin substrate 4 on the side facing the package device 3.

[0011] Each of the package device 3 and the multilayer resin substrate 4 is fixed to the cooling unit 2 by screws. The package device 3 is located in the space formed by the cooling unit 2 and the multilayer resin substrate 4. The cooling unit 2 has the role of dissipating the heat generated in the package device 3. The high-frequency package 1 further has an antenna element connection connector 5 provided on the multilayer resin substrate 4. The antenna element connection connector 5 is radiation-suppressed.

[0012] Figure 3 is a second plan view schematically showing the structure of the high-frequency package 1 according to Embodiment 1. Figure 3 mainly shows the surface layer of the multilayer resin substrate 4 on the side not facing the package device 3. Figure 4 is a second cross-sectional view schematically showing the structure of the high-frequency package 1 according to Embodiment 1. Figure 4 corresponds to Figure 2 and shows signal paths not shown in Figure 2. Figures 3 and 4 also show the transceiver 50 to which the multilayer resin substrate 4 is connected.

[0013] Figure 5 is a schematic plan view showing the structure of the package device 3 of the high-frequency package 1 according to Embodiment 1. As shown in Figure 2, the package device 3 has a sealing lid 31. Figure 5 schematically shows the structure of the package device 3 with the sealing lid 31 removed. Figure 6 is a schematic cross-sectional view showing the structure of the package device 3 of the high-frequency package 1 according to Embodiment 1. Figure 6 shows a cross-section when the package device 3 is cut along the line VI-VI in Figure 5. Figure 6 schematically shows the structure of the package device 3 with the sealing lid 31 removed.

[0014] As shown in FIGS. 2, 5, and 6, the package device 3 further includes a carrier 32, a monolithic microwave integrated circuit 33 mounted on the carrier 32, and a multilayer ceramic substrate connected to the monolithic microwave integrated circuit 33. The sealing lid 31 covers the monolithic microwave integrated circuit 33. The carrier 32 functions as a heat spreader for the monolithic microwave integrated circuit 33. The monolithic microwave integrated circuit 33 is mounted on the pedestal portion of the carrier 32. The multilayer ceramic substrate 34 is disposed on the carrier 32 so as to surround the monolithic microwave integrated circuit 33. The multilayer ceramic substrate 34 has a stepped structure. The multilayer ceramic substrate 34 functions as a multilayer sub-substrate that is electrically connected to the multilayer resin substrate 4.

[0015] As shown in FIGS. 2, 5, and 6, the package device 3 further includes a connection pad 35 for high-frequency signals connected to the multilayer ceramic substrate 34, a connection pad 36 for DC power supply and control signals connected to the multilayer ceramic substrate 34, and a wire 37 connecting the monolithic microwave integrated circuit 33 and the multilayer ceramic substrate 34. As described above, the multilayer ceramic substrate 34 has a stepped structure, and the first stage of the multilayer ceramic substrate 34 and the monolithic microwave integrated circuit 33 are connected by the wire 37.

[0016] As shown in FIG. 6, the multilayer ceramic substrate 34 has a high-frequency signal path 38 inside. The high-frequency signal from the monolithic microwave integrated circuit 33 passes through the wire 37 and further through the high-frequency signal path 38 inside the multilayer ceramic substrate 34, and is transmitted to the connection pad 35 for high-frequency signals disposed at the uppermost stage of the multilayer ceramic substrate 34. The control signal from the monolithic microwave integrated circuit 33 passes through the wire 37 and further through the inside of the multilayer ceramic substrate 34, and is transmitted to the connection pad 36 for DC power supply and control signals disposed at the uppermost stage of the multilayer ceramic substrate 34. The multilayer ceramic substrate 34 also has a ground path 39 inside.

[0017] As shown in FIG. 2, a sealing lid 31 is joined to the second layer of the multilayer ceramic substrate 34. Nitrogen is enclosed in the space formed by the sealing lid 31, the carrier 32, and the multilayer ceramic substrate 34. By joining the sealing lid 31 to the multilayer ceramic substrate 34 using solder, the space is in an airtight state. By making the inside of the package device 3 a hollow structure in this way, deterioration of the high-frequency performance of the monolithic microwave integrated circuit 33 is suppressed.

[0018] The multilayer ceramic substrate 34 may be composed of low-temperature co-fired ceramics or high-temperature co-fired ceramics. Since it is only necessary for the multilayer ceramic substrate 34 and the monolithic microwave integrated circuit 33 to be electrically connected, the multilayer ceramic substrate 34 and the monolithic microwave integrated circuit 33 may be electrically connected by means other than the wire 37.

[0019] As shown in FIG. 2, a refrigerant flow path 21 through which refrigerant flows is formed at the bottom of the cooling unit 2. The heat generated in the monolithic microwave integrated circuit 33 is dissipated to the refrigerant through the carrier 32 and further released to the outside of the high-frequency package 1.

[0020] As shown in FIG. 4, the multilayer resin substrate 4 has, on its inner layer, a strip line 41 for high-frequency signals, a strip line 42 for control signals, and a ground strip line 43. As shown in FIGS. 1 and 2, the multilayer resin substrate 4 has, on the surface layer on the side facing the package device 3, a connection pad 44 for high-frequency signals, a connection pad 45 for DC power supply and control signals, and a plurality of spring terminals 46. Each of the plurality of spring terminals 46 is connected to the connection pad 44 for high-frequency signals, the connection pad 45 for DC power supply and control signals, or the ground pad 48. Some of the spring terminals 46 are joined to the connection pad 44 for high-frequency signals of the multilayer resin substrate 4 or the connection pad 45 for DC power supply and control signals. The ground pad 48 is shown in FIG. 7 and will be described later. Surface-mounted components 47 are mounted on the surface layer of the multilayer resin substrate 4 on the side not facing the package device 3.

[0021] The connection pads 44 for high-frequency signals and 45 for DC power and control signals are arranged to correspond to the package device 3. Each of the multiple spring terminals 46 is connected to either the connection pad 44 for high-frequency signals, the connection pad 45 for DC power and control signals, or the ground pad 48. Furthermore, as described above, some of the spring terminals 46 are bonded to the connection pads 44 for high-frequency signals or the connection pads 45 for DC power and control signals on the multilayer resin substrate 4. Each of the multiple spring terminals 46 is connected to the corresponding pad on the package device 3. Each of the multiple spring terminals 46 is in contact with the connection pad 35 for high-frequency signals or the connection pad 36 for DC power and control signals on the package device 3, and is electrically connected to the contacting connection pad. The connection pad 35 for high-frequency signals in Figure 2 is an example of a pad on the package device 3 that corresponds to a spring terminal 46.

[0022] The ground connected to the multilayer resin substrate 4 passes through through vias inside the multilayer resin substrate 4 and is connected to the monolithic microwave integrated circuit 33 via carrier 32. The ground for the high-frequency signal passes through through vias inside the multilayer resin substrate 4 and is connected to the ground pad 48. As described above, the ground pad 48 is shown in Figure 7. As described above, several spring terminals 46 are connected to the connection pads 44 for high-frequency signals or to the connection pads 45 for DC power and control signals on the multilayer resin substrate 4.

[0023] Figure 7 is a schematic diagram showing a part of the structure of the multilayer resin substrate 4 of the high-frequency package 1 according to Embodiment 1. Figure 7 is an enlarged view of the circular portion labeled VII in Figure 1. The multilayer resin substrate 4 further has a plurality of ground pads 48 located on the surface layer facing the package device 3. Figure 7 shows a connection pad 44 for high-frequency signals, a plurality of spring terminals 46, and a plurality of ground pads 48. Some of the plurality of spring terminals 46 are connected to the plurality of ground pads 48. As described above, some of the spring terminals 46 are joined to the connection pad 44 for high-frequency signals or to the connection pads 45 for DC power and control signals of the multilayer resin substrate 4.

[0024] In Embodiment 1, as shown in Figure 7, each circular portion designated as VII in Figure 1 contains nine spring terminals 46 for high-frequency signals, and each of the nine spring terminals 46 for high-frequency signals is arranged in one of the nine sections arranged in a 3x3 grid without overlap. The central spring terminal 46 is connected to a connection pad 44 for high-frequency signals, and the eight spring terminals 46 surrounding the center are connected to one of the eight ground pads 48. This simulates a coaxial structure and suppresses the radiation of high-frequency signals. As described above, some of the spring terminals 46 are joined to the connection pads 44 for high-frequency signals or to the connection pads 45 for DC power and control signals on the multilayer resin substrate 4.

[0025] Similar to the case of high-frequency signals, radiation from DC power supplies and control signals can be suppressed by providing ground pads 48 around the center. Furthermore, since surface mount components 47 can be mounted on the side of the multilayer resin substrate 4 that does not face the package device 3, the high-frequency package 1 contributes to the efficient use of the component mounting area.

[0026] Figure 8 is a schematic diagram showing a part of the high-frequency package 1 to illustrate a part of the connection between the package device 3 and the multilayer resin substrate 4 of the high-frequency package 1 according to Embodiment 1. As shown in Figure 8, the connection pads 36 for DC power and control signals on the package device 3 and the connection pads 45 for DC power and control signals on the multilayer resin substrate 4 are connected via spring terminals 46.

[0027] The assembly of the high-frequency package 1 is described below. When assembling the high-frequency package 1, the package device 3 is mounted on the cooling unit 2 and screwed in place. The multilayer resin substrate 4 is placed over the package device 3 and screwed to the cooling unit 2 so that the connection pads 35 for high-frequency signals and 36 for DC power and control signals on the package device 3 are connected to the corresponding spring terminals 46 on the multilayer resin substrate 4. This allows the high-frequency package 1 to be assembled. The spring terminals 46 can absorb positional misalignment during assembly. Aside from the assembly of the package device 3, the assembly work for the high-frequency package 1 basically consists only of screwing, thus contributing to improved productivity. As described above, several spring terminals 46 are joined to the connection pads 44 for high-frequency signals or the connection pads 45 for DC power and control signals on the multilayer resin substrate 4. Each of the multiple spring terminals 46 is in contact with the connection pad 35 for high-frequency signals or the connection pad 36 for DC power and control signals on the package device 3, and is electrically connected to the contacting connection pad.

[0028] As described above, the high-frequency package 1 according to Embodiment 1 can suppress the degradation of the high-frequency performance of the monolithic microwave integrated circuit 33 by making the inside of the package device 3 a hollow structure. In addition, since the high-frequency package 1 has a cooling section 2, it can dissipate the heat generated in the monolithic microwave integrated circuit 33. Furthermore, since a refrigerant channel 21 through which a refrigerant flows is formed at the bottom of the cooling section 2, the high-frequency package 1 can dissipate the heat generated in the monolithic microwave integrated circuit 33 to the refrigerant, and thereby release that heat to the outside of the high-frequency package 1. In other words, the high-frequency package 1 can improve both high-frequency characteristics and cooling performance. Moreover, since the package device 3 and the multilayer resin substrate 4 are connected by a spring terminal 46, the high-frequency package 1 contributes to improving positional misalignment during component mounting.

[0029] Embodiment 2. Figure 9 is the first schematic diagram showing the structure of the high-frequency package 1A according to Embodiment 2. The high-frequency package 1 according to Embodiment 1 has only one package device 3. The high-frequency package 1A has multiple package devices 3. This is the main difference between Embodiment 1 and Embodiment 2. Figure 9 shows the cooling section 2 in which the multiple package devices 3 are housed, and the multilayer resin substrate 4. The arrows in Figure 9 indicate that the multilayer resin substrate 4 is inverted and mounted on the cooling section 2 during the assembly of the high-frequency package 1A.

[0030] The configuration of each of the multiple package devices 3 in Embodiment 2 is the same as the configuration of the package device 3 in Embodiment 1. The cooling unit 2 in Embodiment 2 has a space in which the multiple package devices 3 can be arranged and housed at the bottom without overlapping. The multiple package devices 3 are arranged in this space without overlapping. The multilayer resin substrate 4 in Embodiment 2 has a number of connection pads 44 for high-frequency signals, connection pads 45 for DC power and control signals, and spring terminals 46 corresponding to the connections with the multiple package devices 3. Figure 10 is a second diagram schematically showing the structure of the high-frequency package 1A according to Embodiment 2, and shows the high-frequency package 1A after the component mounting is completed. A transceiver 50 is also shown in Figure 10.

[0031] High-frequency signals from the multilayer resin substrate 4 are transmitted to the multilayer ceramic substrate 34 via strip lines 41 for some high-frequency signals inside the multilayer resin substrate 4, connection pads 44 for high-frequency signals on the surface, and spring terminals 46. A ground spring terminal 46 is arranged to surround the high-frequency signal transmission section, simulating a coaxial structure, thereby suppressing the radiation of high-frequency signals.

[0032] The high-frequency signal transmitted to the multilayer ceramic substrate 34 is transmitted to the monolithic microwave integrated circuit 33 via wire 37 through the interior of the multilayer ceramic substrate 34. Because the space in which the monolithic microwave integrated circuit 33 is located is hermetically sealed, the high-frequency package 1A can suppress degradation of high-frequency performance compared to conventional microwave devices with resin molding. The heat generated in the monolithic microwave integrated circuit 33 is transferred to the cooling unit 2 via carrier 32. In other words, the structure of the high-frequency package 1A is such that a heat dissipation interface is secured on the side opposite to the electrical interface. The heat transferred to the cooling unit 2 is released from the cooling unit 2 to the outside of the high-frequency package 1A.

[0033] When assembling the high-frequency package 1A, multiple package devices 3 are mounted on the cooling unit 2 and secured with screws. The multilayer resin substrate 4 is placed over the multiple package devices 3 so that the connection pads 35 for high-frequency signals and the connection pads 36 for DC power and control signals of each package device 3 are connected to the corresponding spring terminals 46 on the multilayer resin substrate 4, and the multilayer resin substrate 4 is secured to the cooling unit 2 with screws. This allows the high-frequency package 1A to be assembled. The spring terminals 46 can absorb misalignment during assembly. Figure 9 shows multiple connection screws 6, and the cooling unit 2 and the multiple package devices 3 are fixed by multiple connection screws 6. Figure 10 shows multiple connection screws 7, and the cooling unit 2 and the multilayer resin substrate 4 are fixed by multiple connection screws 7. Some of the spring terminals 46 are joined to the connection pads 44 for high-frequency signals or the connection pads 45 for DC power and control signals on the multilayer resin substrate 4. Each of the multiple spring terminals 46 is in contact with a connection pad 35 for high-frequency signals or a connection pad 36 for DC power and control signals of the package device 3, and is electrically connected to the contacting connection pad.

[0034] The configurations shown in the above embodiments are examples only, and it is possible to combine them with other known technologies, combine different embodiments, and omit or modify parts of the configuration without departing from the spirit of the invention. [Explanation of Symbols]

[0035] 1, 1A high-frequency package, 2 cooling section, 3 package device, 4 multilayer resin substrate, 5 antenna element connection connector, 6, 7 connection screws, 21 coolant flow path, 31 sealing lid, 32 carrier, 33 monolithic microwave integrated circuit, 34 multilayer ceramic substrate, 35, 44 connection pads for high-frequency signals, 36, 45 connection pads for DC power and control signals, 37 wire, 38 high-frequency signal path, 39 ground path, 41 strip line for high-frequency signals, 42 strip line for control signals, 43 strip line for ground, 46 spring terminal, 47 surface mount components, 48 ​​ground pad, 50 transceiver.

Claims

1. A box-shaped cooling unit without a lid, The package device housed in the aforementioned cooling section, The cooling section comprises a multilayer resin substrate that covers the space of the cooling section, The package device comprises a carrier, a monolithic microwave integrated circuit mounted on the carrier, a sealing lid covering the monolithic microwave integrated circuit, a multilayer ceramic substrate connected to the monolithic microwave integrated circuit, connection pads for high-frequency signals connected to the multilayer ceramic substrate, and connection pads for DC power and control signals connected to the multilayer ceramic substrate. The multilayer resin substrate has strip lines for high-frequency signals in its inner layer, and on its back surface, it has connection pads for high-frequency signals, connection pads for DC power and control signals, and a plurality of spring terminals. Each of the plurality of spring terminals is connected to the connection pad for the high-frequency signal or the connection pad for the DC power supply and control signal, The package device is fixed to the cooling section by screws, Each of the plurality of spring terminals is connected to the corresponding pad of the package device. A high-frequency package characterized by the following features.

2. A second package device housed in the cooling section and having the same configuration as the package device. The high-frequency package according to claim 1, further comprising the above.

3. The package device placed on the cooling section, The package device comprises a multilayer resin substrate connected to the aforementioned package device, The aforementioned package device is A heat spreader thermally connected to the cooling unit, The heat spreader comprises a monolithic microwave integrated circuit, a multilayer ceramic substrate arranged around the monolithic microwave integrated circuit and connected to the monolithic microwave integrated circuit, and a multilayer sub-sub The multilayer resin substrate has electronic components mounted on its surface, and on its back surface it has a plurality of connection pads for high-frequency signals and a plurality of connection pads for DC power supplies and control signals. Each of the multiple connection pads for high-frequency signals and the multiple connection pads for DC power and control signals on the multilayer resin substrate is connected to the corresponding connection pad of the package device via a spring terminal. A high-frequency package characterized by the following features.

4. The multiple connection pads for high-frequency signals on the multilayer resin substrate are surrounded by multiple ground pads. The high-frequency package according to feature 3.

5. The aforementioned multilayer sub-substrate is a multilayer ceramic substrate. The high-frequency package according to feature 3.

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