JP6922561B2 - Electronic devices and methods for manufacturing electronic devices - Google Patents

Description

The present invention relates to an electronic device and a method for manufacturing the electronic device.

Conventionally, in a substrate mounting structure in which a chip is mounted on a mounting substrate with a flip chip and an underfill material is filled between the two, the underfill material is applied to at least one part of the mounting substrate or the chip. There is a substrate mounting structure characterized in that a groove structure for preventing intrusion is formed and has an underfill material unfilled region (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2003-243444

By the way, in the conventional substrate mounting structure (electronic device), an underfill material unfilled region is provided in a portion corresponding to an optical interface on the chip side to secure an optical path, and when the chip operates at a high frequency, an underfill material is provided. There is no disclosure about the deviation of the operating frequency or the dielectric loss tangent due to the high dielectric constant of the fill material. The deviation of the operating frequency and the dielectric loss tangent lead to the loss of the electronic device.

Therefore, it is an object of the present invention to provide an electronic device with reduced loss and a method for manufacturing the electronic device.

The electronic device according to the embodiment of the present invention is provided between the substrate, the high frequency module provided facing the substrate, and the substrate and the high frequency module, and the plurality of terminals of the substrate and the high frequency module. A carbon extending in a direction from the substrate to the high-frequency module, surrounding the plurality of pillars in a plan view between the plurality of pillars connecting the plurality of terminals and the high-frequency module and the substrate. It is poured into the gap between the nanotube and the carbon nanotube, and includes an underfill that surrounds the plurality of pillars in a plan view between the high frequency module and the substrate.

It is possible to provide an electronic device with reduced loss and a method for manufacturing the electronic device.

It is sectional drawing which shows the electronic device 100 of embodiment. It is a figure which shows the manufacturing process of the electronic device 100. It is a figure which shows the electronic device 100M of the modification of embodiment.

Hereinafter, an electronic device of the present invention and an embodiment to which the method for manufacturing the electronic device is applied will be described.

<Embodiment>
FIG. 1 is a cross-sectional view showing the electronic device 100 of the embodiment. Here, the XYZ coordinate system will be used for description. Here, for convenience of explanation, the XY plane view is referred to as a plane view, and the Z-axis direction is referred to as a height direction (vertical direction).

The electronic device 100 includes a wiring board 110, a high frequency module 120, a copper pillar 130, a CNT (Carbon Nano Tube) 140, and an underfill 150.

The wiring board 110 is, for example, a wiring board such as FR-4 (Flame Retardant type 4), and has terminals 111A and 111B on the upper surface. The wiring board 110 is an example of a board. A semiconductor chip, an electronic module, an electronic component, or the like other than the high frequency module 120 may be mounted on the wiring board 110. The wiring board 110 may be a multilayer board having a wiring layer other than the upper surface. Although FIG. 2 shows two terminals 111A and 111B, the wiring board 110 actually has more terminals.

The high frequency module 120 has terminals 121A and 121B on the lower surface, and is mounted on the wiring board 110 by copper pillars 130, CNT 140, and underfill 150. The high frequency module 120 has a rectangular shape in a plan view.

The high frequency module 120 is, for example, an LSI (Large Scale Integrated circuit) or a millimeter wave module that operates at a high frequency of 30 GHz or more. The high frequency means, for example, a frequency of 30 GHz or more. Here, the high frequency band may be regarded as a millimeter wave band. The millimeter wave band is, for example, a radio wave having a wavelength of about 1 mm to 10 mm, and is a band having a frequency of about 30 GHz to 300 GHz.

The terminals 121A and 121B are connected to the terminals 111A and 111B of the wiring board 110 via the copper pillar 130. Although FIG. 2 shows two terminals 121A and 121B, the high frequency module 120 may actually have more terminals.

The copper pillar 130 is a columnar metal wiring that connects the terminals 111A and 111B of the wiring board 110 and the terminals 121A and 121B of the high frequency module 120. The copper pillar 130 is an example of a pillar or a conductive pillar. The copper pillar 130 is produced, for example, by depositing copper plating by electroplating in a state where a mask is formed on a portion of the wiring board 110 excluding terminals 111A and 111B. The height of the copper pillar 130 in the Z-axis direction is equal to the height of the CNT 140 minus the thickness of the terminals 111A and 121A or the thickness of the terminals 111B and 121B.

Although two copper pillars 130 are shown in FIG. 1, in reality, the copper pillars 130 may be provided with more copper pillars 130. All copper pillars 130 connected to the high frequency module 120 are arranged inside the rectangular contour of the high frequency module 120 in plan view.

The CNT 140 is a rectangular annular member having a sheet structure provided on the upper surface of the wiring board 110 so as to surround all the copper pillars 130 connected to the high frequency module 120 in a plan view. More specifically, the CNT 140 is provided along the rectangular outer circumference of the high frequency module 120 in a plan view, and the CNT 140 located inside the rectangular annular region is located below the high frequency module 120. The CNT 140 located outside the rectangular annular region is located outside the outer circumference of the high frequency module 120.

The CNT 140 located on the innermost side of the rectangular annular region is, for example, located 50 micrometers inside the rectangular outer circumference of the high frequency module 120 (from the side wall of the high frequency module 120).

The height of the CNT 140 is equal to the height of the copper pillar 130 plus the thicknesses of the terminals 111A and 121A or the thicknesses of the terminals 111B and 121B. The upper end of the CNT 140 located below the high frequency module 120 in a plan view is in contact with the lower surface of the high frequency module 120. The CNT 140 extends along the direction from the wiring board 110 toward the high frequency module 120.

Here, the direction from the wiring board 110 toward the high frequency module 120 is synonymous with the direction from the high frequency module 120 toward the wiring board 110, and is the Z-axis direction. Further, the direction in which the CNT 140 extends is the direction in which the CNT 140 grows in a tubular shape.

Further, the fact that the CNT 140 extends along the direction from the wiring board 110 toward the high frequency module 120 means that the CNT 140 extends parallel to the Z-axis direction and X even if it is not parallel to the Z-axis direction. It means that the CNT 140 extends in the Z-axis direction as a whole, not in the axial direction and the Y-axis direction.

Further, the CNT 140 is provided, for example, by transferring a bundle of vertically oriented multilayer carbon nanotubes onto a resin sheet (not shown in FIG. 1) provided on the upper surface of the wiring board 110.

Vertically oriented multi-walled carbon nanotubes are CNTs oriented in the vertical direction on a substrate for making CNTs. The root side near the substrate grows substantially perpendicular to the substrate, but curves as the distance from the substrate increases. It may include a section that does not grow in the vertical direction, such as when it is bent or when it is bent. As an example, the CNT 140 is obtained by transferring vertically oriented multi-walled carbon nanotubes, which may include such curved CNTs or bent sections, onto a resin sheet provided on the upper surface of the wiring board 110.

Therefore, when vertically oriented multi-walled carbon nanotubes are used, it is said that the CNT 140 extends along the direction (Z-axis direction) from the wiring board 110 to the high-frequency module 120 between the wiring board 110 and the high-frequency module 120. , The vertically oriented multi-walled carbon nanotubes are provided so that the orientation direction faces the Z-axis direction. Although vertically oriented multi-walled carbon nanotubes have high thermal conductivity (about 1500 W / m · K), the distance between each one on the root side near the substrate during synthesis is tens to hundreds of nanometers. It is about a meter, and as it approaches the tip, several to several tens of bundles are bundled, and the distance between each bundle is about several nanometers. Such a bundle-shaped CNT 140 is a nanocarbon bonded structure having excellent stress absorption characteristics.

Here, a mode in which the height of the CNT 140 is equal to the height of the copper pillar 130 plus the thicknesses of the terminals 111A and 121A or the thicknesses of the terminals 111B and 121B will be described. , The height of the CNT 140 may be higher than the height of the copper pillar 130 plus the thicknesses of the terminals 111A and 121A or the thicknesses of the terminals 111B and 121B. In this case, of the CNTs 140, the CNTs 140 located below the high-frequency module 120 in a plan view come into contact with the lower side of the high-frequency module 120 in a state of being pressed in the height direction, and are outside the high-frequency module 120 in a plan view. A portion of the located CNT 140 contacts the side surface of the high frequency module 120.

The underfill 150 is poured into the gap of the CNT 140 and closes the gap of the CNT 140. Since the CNTs 140 are arranged at intervals of several nanometers to several hundreds of nanometers, the underfill material for forming the underfill 150 is a gap between the CNTs 140 due to the suction effect of the capillary phenomenon. Or it is sucked into the gap between the bundles. That is, the underfill 150 is in contact with the lower surface of the high frequency module 120 in a coexisting manner together with the CNT 140 on the lower surface of the high frequency module 120. The underfill 150 also contacts the lower part of the side surface of the high frequency module 120 and fixes the lower part of the side surface of the high frequency module 120.

Therefore, the underfill 150 is provided in a rectangular annular region (region in which the CNTs 140 are arranged) surrounding all the copper pillars 130 connected to the high frequency module 120 in a plan view, and fixes the bundled CNTs 140 to each other. At the same time, the high frequency module 120 is fixed to the wiring board 110. Further, since the underfill material is sucked into the gap of the CNT 140, the underfill material does not flow inward of the CNT 140 provided in the rectangular annular shape in a plan view.

Since the gap between each CNT 140 or the gap between bundles is about several nanometers to several hundred nanometers, the suction effect is large, but the region where CNT 140 does not exist (CNT 140 provided in a rectangular ring in a plan view). This is because the suction effect does not occur in the area inside the area).

In this way, the underfill 150 seals the gap of the CNT 140, and the underfill material does not flow into the region where the CNT 140 does not exist, so that the gap 10 is formed between the wiring board 110 and the high frequency module 120. Provided. The gap 10 is a rectangular parallelepiped space whose upper and lower sides are sealed by the wiring board 110 and the high-frequency module 120, and its four sides are sealed by the CNT 140 and the underfill 150. The copper pillar 130 is located inside the void 10. The void 10 also extends between the copper pillar 130 and the CNT 140 and the underfill 150 in the cross section shown in FIG.

Further, when the void 10 is provided, the inside of the void 10 can be filled with the inert gas by sealing in an atmosphere of an inert gas such as nitrogen or argon or in a vacuum, or the inside of the void 10 can be filled. It is possible to create a vacuum, improve reliability by suppressing humidity, and further suppress reduction of high frequency characteristics.

The underfill material (resin material) for forming the underfill 150 is not particularly limited as long as it can be embedded between bundles of CNTs 140 and / or between individual CNTs 140s, and is particularly limited. Although not, the following can be used. For example, acrylic resin, epoxy resin, silicone resin, polyvinyl resin, wax and the like can be applied.

Next, a method of manufacturing the electronic device 100 will be described. FIG. 2 is a diagram showing a manufacturing process of the electronic device 100.

First, as shown in FIG. 2A, copper pillars 130 are provided on the terminals 111A and 111B on the upper surface of the wiring board 110, and a resin sheet 141 is provided on the upper surface of the wiring board 110. The copper pillar 130 is produced, for example, by depositing copper plating by electroplating in a state where a mask is formed on a portion of the wiring board 110 excluding terminals 111A and 111B. The mask used when manufacturing the copper pillar 130 may be removed by using an etching solution.

The resin sheet 141 is, for example, a silicone grease, a hot melt resin (a hot melt resin such as a polyamide hot melt resin, a polyurethane hot melt resin, or a polyolefin hot melt resin), or a heat conductive sheet, and is a rectangular annular shape provided with a CNT 140. It may be applied to the area of the above by screen printing or the like.

Next, as shown in FIG. 2 (B), a high-frequency module 120 is prepared by transferring the CNT 140 onto the resin sheet 141 and further providing the terminals 121A and 121B on the lower surface, and soldering the terminals 121A and 121B and copper. Join the pillars 130. A conductive adhesive may be used instead of the solder, or the terminals 121A and 121B and the copper pillar 130 may be bonded by thermocompression bonding.

Transcription of CNT140 may be performed as follows. A bundle of vertically oriented multi-walled carbon nanotubes is synthesized in advance on a substrate for CNT production, and the bundle of vertically oriented multi-walled carbon nanotubes is peeled off from the substrate for CNT production and transferred onto a silicone rubber, and further, a silicone rubber-like vertical. By transferring the bundle of oriented multilayer carbon nanotubes onto the resin sheet 141, the CNTs 140 can be arranged on the resin sheet 141.

In the state shown in FIG. 2B, the tip of the CNT 140 is exposed on the upper end side of the CNT 140 located outside the outer circumference of the high frequency module 120 in a plan view like a sword mountain.

Next, as shown in FIG. 2C, the underfill material 151 is applied from the upper end side of the CNT 140 located outside the outer circumference of the high frequency module 120 in a plan view. The underfill material 151 spreads among all the CNTs 140 while being sucked into the gaps of the CNTs 140, and also spreads between the CNTs 140 located below the high frequency module 120.

As a result, as shown in FIG. 2D, the underfill 150 poured between the CNTs 140 is completed. In this state, the lower surface of the high frequency module 120 along the outer circumference is fixed to the wiring board 110 by the CNT 140 and the underfill 150.

The underfill material 150 is vertically sealed by the wiring board 110 and the high frequency module 120 in order to fix the bundle-shaped CNTs 140 provided in a rectangular annular shape in a plan view and seal the gap between the CNTs 140, and the CNTs 140 and the underfill material 150. A void 10 appears in which the four sides are sealed by the material 150.

The CNT 140 can be manufactured by the following method. Iron having a thickness of 2.5 nm is deposited as a catalyst metal on the surface of a substrate for CNT production by a sputtering method. In addition, an electron beam vapor deposition (EB) method or a molecular beam epitaxy (MBE) method may be used for depositing the catalyst metal. As the substrate, a silicon substrate with a thermal oxide film (thickness of about 300 nm) is used, but a silicon substrate, an alumina substrate, a quartz substrate, or a sapphire substrate may also be used, and there is no particular limitation.

Subsequently, by the hot filament chemical vapor deposition (CVD) method, a mixed gas of acetylene and argon was used as the raw material gas, the substrate for CNT production was heated to 620 ° C., and carbon nanotubes were grown at a pressure of 1 kPa. do. In addition to this, a remote plasma CVD method, a plasma CVD method, and a thermal CVD method may be used as the growth method.

As a result of the growth, a bundle of carbon nanotubes grows perpendicular to the substrate for CNT production. The length of the carbon nanotubes can be arbitrarily adjusted according to the growth conditions and the growth time. When the temperature of the substrate for CNT production is 620 ° C and the pressure is 1 kPa, the carbon nanotubes have a growth time of 60 minutes and are about 150 microns. You can get a bunch of.

When an iron catalyst having a thickness of 1 nm is used under the same synthesis conditions, multi-walled carbon nanotubes having a length of about 250 microns can be grown. As the raw material gas for the multi-walled carbon nanotubes, for example, acetylene can be used. In addition to acetylene, hydrocarbons such as methane and ethylene, or alcohols such as ethanol and methanol may be used.

The catalyst species and the base film of the catalyst are not similarly limited, and the catalyst species may be a metal or an alloy thereof that can be a catalyst for carbon nanotubes such as cobalt, nickel, iron, gold, silver, and platinum. Further, although the form in which the base film is not used is described here, molybdenum, titanium, hafnium, zirconium, niobium, vanadium, tantalum nitride, titanium silicide, aluminum, aluminum oxide, titanium oxide, tantalum, and tungsten are used as the base film. A metal or alloy base film containing at least one of copper, gold, platinum and the like may be used. When iron, cobalt, nickel or the like is used as the catalyst, the nanotubes can be grown in the range of 300 ° C. to 1100 ° C., preferably in the range of 500 ° C. to 800 ° C.

As described above, in the electronic device 100, the gap 10 is provided under the high frequency module 120. The gap 10 is a rectangular parallelepiped space whose upper and lower sides are sealed by the wiring board 110 and the high-frequency module 120, and its four sides are sealed by the CNT 140 and the underfill 150, and the copper pillar 130 passes through the inside of the gap 10. ..

Here, a comparative electronic device that does not include the CNT 140, has no gap 10 under the high-frequency module, and has an underfill as a whole between the high-frequency module and the wiring board will be examined. The underfill material is a bonding material that stably fixes the high-frequency module to the wiring board, but since it has a higher dielectric constant than air, it is dielectric loss tangent when placed near the module driven by high frequency. There is a loss of high frequency characteristics due to the large tan δ) and a loss due to the deviation of the operating frequency of the high frequency module from the design value. The dielectric constant of the resin underfill material is about 2 to about 3. Therefore, in the electronic device for comparison, the loss becomes large.

Here, in the electronic device for comparison, it is difficult to fix the high frequency module to the wiring board while preventing the underfill material from flowing under the high frequency module. This is because it is not easy to control the fluidity of the underfill material.

On the other hand, in the electronic device 100 of the embodiment, the CNT 140 having a sheet structure is arranged on the outer peripheral portion of the high frequency module 120, and the underfill material 151 is poured (sucked) into the CNT 140 to wire the high frequency module 120. A gap 10 can be provided under the high frequency module 120 while being stably fixed to the substrate 110.

If the gap 10 is provided under the high-frequency module 120 in this way, air will be present in the space under the high-frequency module 120, as compared with the case where an underfill is present as in a comparative electronic device. Therefore, the dielectric constant in the region below the high frequency module 120 can be lowered, and the loss of the high frequency characteristics and the like of the high frequency module 120 can be reduced.

Therefore, according to the embodiment, it is possible to provide the electronic device 100 with reduced loss.

Further, the wiring board 110 and the high frequency module 120 are connected by a CNT 140, and the CNT 140 has high thermal conductivity and high pressure response to a load, so that the heat dissipation is improved and the impact resistance is increased. Can be made to.

As a result, even if heat is generated due to the high frequency driving of the high frequency module 120, stable operation of the high frequency module 120 can be realized for a long period of time, and even if an external impact is applied, the wiring board 110 and the high frequency are generated. A stable electrical connection with the module 120 by the copper pillar 130 can be ensured, and reliability can be improved.

Although the electronic device 100 including the copper pillar 130 has been described above, the CNT may be used as the pillar instead of the copper pillar 130. FIG. 3 is a diagram showing an electronic device 100M of a modified example of the embodiment.

The electronic device 100M includes a wiring board 110, a high frequency module 120, a CNT pillar 130M, a CNT 140, and an underfill 150. The electronic device 100M has a configuration in which the copper pillar 130 of the electronic device 100 shown in FIG. 1 is replaced with the CNT pillar 130M, and the terminals 111A and 111B of the wiring board 110 and the terminals 121A and 121B of the high frequency module 120 are connected.

Like the CNT 140, the CNT pillar 130M extends in the direction from the wiring board 110 toward the high frequency module 120. Further, the CNT pillar 130M connects the terminals 111A and 111B and the terminals 121A and 121B.

Such a CNT pillar 130M can be produced, for example, by growing a bundle of carbon nanotubes on the terminals 111A and 111B. For example, an aluminum (Al) layer (15 nanometers) and an iron (Fe) layer (on top of metal terminals 111A, 111B such as gold or platinum, for example, on a tantalum (Ta) layer (30 nanometers)). 2.5 nanometers). The tantalum layer is provided to prevent the gold or platinum used as the terminals 111A and 111B from diffusing toward the catalyst side, and the aluminum layer and the iron layer are used as a catalyst for growing a bundle of carbon nanotubes.

A tantalum layer, an aluminum layer, and an iron layer are deposited on the entire upper surface of the wiring board 110 (the entire upper surface of the terminals 111A and 111B and the portion where the terminals 111A and 111B are not provided) by a sputtering method, and photolithography is performed. A tantalum layer, an aluminum layer, and an iron layer are formed only on the upper surfaces of the terminals 111A and 111B by patterning with.

Subsequently, by the hot filament chemical vapor deposition (CVD) method, a mixed gas of acetylene and argon (10%) was used as the raw material gas, and the carbon nanotubes were formed at a temperature of the wiring substrate 110 at 620 ° C. and a pressure of 1 kPa. grow up. The growth time is 20 minutes. As a result, the bundle of carbon nanotubes as the CNT pillar 130M can be obtained with a length of about 20 microns. The length of the CNT can be adjusted by the synthesis conditions such as the synthesis time and the synthesis temperature, the catalyst film thickness, and the catalyst type.

With such CNT pillars 130M formed on the terminals 111A and 111B of the wiring board 110, the CNT pillars 130M are joined to the terminals 121A and 121B with a conductive adhesive. Further, the electronic device 100M can be manufactured by applying the underfill material 151 from the upper end side of the CNT 140 to form the underfill 150.

In addition to the conductive adhesive, hot melt resins such as polyamide hot melt resin, polyurethane hot melt resin, and polyolefin hot melt resin, solder, and metal nanopaste are used to bond the CNT pillars 130M to the terminals 121A and 121B. You may use it.

As a method for growing the CNT pillar 130M, a remote plasma CVD method, a plasma CVD method, or a thermal CVD method may be used in addition to the above. The raw material gas for the multi-walled carbon nanotubes is not limited to acetylene, and hydrocarbons such as methane and ethylene, or alcohols such as ethanol and methanol may be used.

Similarly, the catalyst and the ground film are not limited to those described above, and the catalyst species may be a metal or an alloy thereof that can be a catalyst for carbon nanotubes such as cobalt, nickel, iron, gold, silver, and platinum. The base film is a metal containing at least one of molybdenum, titanium, hafnium, zirconium, niobium, vanadium, tantalum nitride, titanium silicide, aluminum, aluminum oxide, titanium oxide, tantalum, tungsten, copper, gold, platinum and the like. A film structure made of an alloy may be used.

Similar to CNT140, the CNT pillar 130M may use a conductive adhesive, a polyamide hot melt resin, a polyurethane hot melt resin, a hot melt resin such as a polyolefin hot melt resin, solder, or a metal nanopaste. In that case, it may be applied to the rectangular annular region where the CNT 130 is provided by screen printing or the like.

Although the electronic device according to the exemplary embodiment of the present invention and the method for manufacturing the electronic device have been described above, the present invention is not limited to the specifically disclosed embodiments, and claims for patent. Various modifications and changes are possible without departing from the range of.
The following additional notes will be further disclosed with respect to the above embodiments.
(Appendix 1)
With the board
A high-frequency module provided facing the substrate and
A plurality of pillars provided between the substrate and the high-frequency module and connecting a plurality of terminals of the substrate and a plurality of terminals of the high-frequency module, respectively.
Between the high-frequency module and the substrate, carbon nanotubes that surround the plurality of pillars in a plan view and extend along the direction from the substrate to the high-frequency module.
An electronic device that is poured into the gaps between the carbon nanotubes and includes an underfill that surrounds the plurality of pillars in a plan view between the high frequency module and the substrate.
(Appendix 2)
The electronic device according to Appendix 1, wherein a region surrounded by the carbon nanotube, the underfill, and the plurality of pillars in a plan view between the substrate and the high frequency module is a void.
(Appendix 3)
The electronic device according to Appendix 1 or 2, wherein the pillar is a metal pillar or a carbon nanotube pillar.
(Appendix 4)
The electronic device according to Appendix 3, further comprising a catalytic metal layer provided on the surface of a plurality of terminals of the substrate and used for the growth of the carbon nanotube pillars.
(Appendix 5)
The distance between each of the carbon nanotubes on the root side near the substrate during synthesis is about several tens to several hundreds of nanometers, and as the carbon nanotubes approach the tip, several to several tens of carbon nanotubes are bundled and one. The electronic device according to any one of Supplementary note 1 to 4, wherein each of the electronic devices has a bundle-like structure having an interval of about several nanometers.
(Appendix 6)
Among the carbon nanotubes surrounding the plurality of pillars between the high frequency module and the substrate, the position of the carbon nanotube located on the innermost side in the plan view is within 50 micrometers from the side surface of the high frequency module. , The electronic device according to any one of Appendix 1 to 5.
(Appendix 7)
A process of providing a plurality of pillars, one end of which is connected to each of a plurality of terminals on the first surface of the board, and
A step of surrounding the plurality of pillars in a plan view on the first surface of the substrate and providing carbon nanotubes extending along a direction protruding from the first surface.
A step of providing a high-frequency module on the plurality of pillars and the carbon nanotubes and joining a plurality of terminals of the high-frequency module to the other ends of the plurality of pillars.
A method for manufacturing an electronic device, which comprises a step of pouring an underfill material into a gap between the carbon nanotubes so as to surround the plurality of pillars in a plan view.

100 Electronic device 110 Wiring board 111A, 111B terminal 120 High frequency module 121A, 121B terminal 130 Copper pillar 140 CNT
150 Underfill 100M Electronics 130M CNT Pillar

Claims (5)

With the board
A high-frequency module provided facing the substrate and
A plurality of pillars provided between the substrate and the high-frequency module and connecting a plurality of terminals of the substrate and a plurality of terminals of the high-frequency module, respectively.
Between the high-frequency module and the substrate, carbon nanotubes that surround the plurality of pillars in a plan view and extend along the direction from the substrate to the high-frequency module.
An electronic device that is poured into the gaps between the carbon nanotubes and includes an underfill that surrounds the plurality of pillars in a plan view between the high frequency module and the substrate. The electronic device according to claim 1, wherein a region surrounded by the carbon nanotubes, the underfill, and the plurality of pillars in a plan view between the substrate and the high frequency module is a void. The electronic device according to claim 1 or 2, wherein the pillar is a metal pillar or a carbon nanotube pillar. The electronic device according to claim 3, further comprising a catalytic metal layer provided on the surface of a plurality of terminals of the substrate and used for the growth of the carbon nanotube pillars. A process of providing a plurality of pillars, one end of which is connected to each of a plurality of terminals on the first surface of the board, and
A step of surrounding the plurality of pillars in a plan view on the first surface of the substrate and providing carbon nanotubes extending along a direction protruding from the first surface.
A step of providing a high-frequency module on the plurality of pillars and the carbon nanotubes and joining a plurality of terminals of the high-frequency module to the other ends of the plurality of pillars.
A method for manufacturing an electronic device, which comprises a step of pouring an underfill material into a gap between the carbon nanotubes so as to surround the plurality of pillars in a plan view.

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