JPWO2020110741A1 - Radar device - Google Patents

Abstract

To provide a radar device that can suppress the temperature rise of electronic components. A substrate (10) provided with a MMIC chip (14) on one main surface (11), a horn (20) arranged on one main surface (11) of the substrate (10), and a substrate (10). It is a radar device (1) provided with a heat radiating plate (40) provided on the other main surface (12), and a heat radiating pattern (15) is formed on one main surface (11) of the substrate (10). The MMIC chip (14) is connected to the heat dissipation pattern (15) via the thermal paste (G1), and the horn (20) is connected to the heat dissipation pattern (15) via the thermal paste (G2). There is.

Description

The present invention relates to a radar device.

In recent years, as a basic technology for automatic driving and the like, a radar device for detecting an obstacle around a vehicle has been developed. An electronic component that generates radio waves is mounted on the radar device, and since this electronic component consumes a particularly large amount of power, there is a risk of malfunction due to heat generation. For this reason, a radar device that ensures heat dissipation of electronic components is known (see, for example, Patent Document 1). In the radar device described in Patent Document 1, a ground pattern is formed on the upper surface of the substrate so as to surround the electronic components. The frame is installed so as to be in contact with the ground pattern on the substrate, and the heat generated by the electronic components is released to the frame via the ground pattern.

Japanese Unexamined Patent Publication No. 2017-161322

However, in the above radar device, although a ground pattern is formed around the electronic component, the heat generated by the electronic component is not directly transmitted to the ground pattern. There is a slight gap between the electronic component and the ground pattern, and the thermal resistance between the electronic component and the ground pattern is large, so the temperature of the electronic component cannot be sufficiently lowered. Therefore, the temperature of the electronic component may rise above the permissible temperature.

The present invention solves the above problems, and an object of the present invention is to provide a radar device capable of suppressing a temperature rise of an electronic component.

The radar device of one aspect of the present invention includes a substrate provided with electronic components on one main surface, a horn arranged on one main surface of the substrate, and heat dissipation provided on the other main surface of the substrate. A radar device including a plate, wherein a heat dissipation pattern is formed on one main surface of the substrate, and the electronic component is connected to the heat dissipation pattern via a first heat dissipation member and the heat dissipation pattern is described. The horn is connected to the heat dissipation pattern via a second heat dissipation member.

According to the present invention, in addition to the heat dissipation path in the thickness direction of the substrate from the electronic component to the heat sink, a heat dissipation path having a small thermal resistance from the electronic component to the horn is formed, effectively raising the temperature of the electronic component. It can be suppressed. Further features relating to the present invention will become apparent from the description herein and the accompanying drawings. In addition, problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

An exploded perspective view of the radar device according to the first embodiment. The cross-sectional schematic diagram of the radar apparatus which concerns on 1st Embodiment. FIG. 3A is an explanatory diagram of a radio wave radiation state according to a comparative example, and FIG. 3B is an explanatory diagram of a radio wave radiation state of the first embodiment. FIG. 4A is an explanatory diagram of a radio wave radiating state by the plurality of antennas according to the comparative example, and FIG. 4B is an explanatory diagram of a radio wave radiating state by the plurality of antennas of the first embodiment. FIG. 5A is an explanatory diagram of a heat transfer path and a heat dissipation path according to a comparative example, and FIG. 5B is an explanatory diagram of a heat transfer path and a heat dissipation path according to the first embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the second embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the third embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the fourth embodiment. FIG. 5 is a schematic cross-sectional view of the radar device of the fifth embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the sixth embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the seventh embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the eighth embodiment. FIG. 6 is a schematic cross-sectional view of the radar device of the ninth embodiment.

[First Embodiment]
Hereinafter, the overall configuration of the radar device according to the first embodiment will be described with reference to FIG. FIG. 1 is an exploded perspective view of the radar device according to the first embodiment. In the following description, a millimeter-wave radar will be illustrated as a radar device, but the technology of the present disclosure can be used for another radar device that emits radio waves to detect obstacles.

As shown in FIG. 1, the radar device 1 is a millimeter-wave radar device, which emits radio waves in the millimeter-wave band and receives reflected waves from an obstacle to detect an obstacle. A plurality of MMIC (Monolithic Microwave Integrated Circuit) chips 14 are provided on one main surface 11 of the substrate 10 of the radar device 1. A plurality of antennas 13 are connected to each MMIC chip 14 via a feeder line (not shown). A radio wave is radiated from each antenna 13 by the power supply from each MMIC chip 14, and the radio wave captured by each antenna 13 is sent to each MMIC chip 14 through a feeding line.

The antenna 13 may be a flat antenna such as a patch antenna provided on the substrate 10 or a surface mount type chip antenna provided on the substrate 10. Although the MMIC chip 14 for transmission / reception is arranged as a semiconductor chip on the substrate 10, the MMIC chip 14 for transmission and the MMIC chip 14 for reception may be arranged individually. As the semiconductor chip, another MIC (Microwave Integrated Circuit) chip may be used. Further, as the substrate 10, a glass epoxy substrate, a ceramic substrate, or the like may be used, or a high-frequency substrate made of a fluororesin having a low dielectric constant may be used.

On one main surface 11 of the substrate 10 of the radar device 1, a resin horn 20 having a rectangular shape in a plan view and whose outer surface is metal-plated is arranged. In the horn 20, a waveguide 23 is formed at a position corresponding to a plurality of antennas 13 on the substrate 10. The types of the waveguides 23 are divided into short-distance, medium-distance, and long-distance. By emitting radio waves from the plurality of waveguides 23 to the outside, it is possible to detect obstacles having different distances from the radar device 1. Each waveguide 23 is formed in a prismatic or conical shape by the tapered surface of the horn 20 so as to become wider as the distance from one main surface 11 of the substrate 10 increases.

The horn 20 includes PBT (Polybutylene Terephthalate) resin, PPS (Poly Phenylene Sulfide) resin, PP (Poly Propylene) resin, ABS (Acrylonitrile Butadiene Styrene) resin, PS (Poly Styrene) resin, and PE (Poly Ethylene) resin. , PVC (Poly Vinyl Chloride) resin, PC (Poly Carbonate) resin, PET (Poly Ethylene Terephthalate) resin, LCP (Liquid Crystal Polymer) resin, PPO (Poly Phenylene Oxide) resin, epoxy (Epoxy) resin, Si (Silicone) A thermoplastic resin containing a resin, a polyester resin or the like as a main component, or a heat-curable resin that is lightweight and has a low thermal conductivity may be used. The metal film 28 (see FIG. 2) formed on the outer surface of the horn 20 by metal plating has silver (Ag), copper (Cu), gold (Au), and nickel (Ni) having high thermal conductivity and shielding properties. ), Tin (Sn) and the like may be used. The metal film 28 on the outer surface of the horn 20 may be formed by a sputtering method, an inkjet method, a screen printing method, a CVD (Chemical Vapor Deposition) method, a PVD (Physical Vapor Deposition) method, or the like, in addition to plating.

On the horn 20, a lens 30 having a rectangular shape in a plan view is arranged so as to cover the plurality of waveguides 23. On the back surface of the lens 30 on the substrate 10 side, a plurality of lens surfaces 31 (see FIG. 2) are formed corresponding to the plurality of waveguides 23 of the horn 20. The radio waves radially diffused from the antenna 13 in the waveguide 23 are converted into plane waves by the lens 30 and emitted to the outside. The reflected wave from the outside is converged in the waveguide 23 by the lens 30 and received by the antenna 13. A dielectric material such as PBT resin or PPS resin may be used for the lens 30.

The outer edges of the horn 20 and the lens 30 are held by a rectangular frame-shaped housing 35.
The housing 35 has an opening edge portion 36 that prevents the horn 20 and the lens 30 from coming off, and a side wall portion 37 that forms a side surface of the radar device 1. A cover 39 forming the surface of the radar device 1 is fixed on the opening edge portion 36 of the housing 35. The cover 39 bulges except for the outer peripheral portion fixed to the housing 35, and functions as a radome that protects the inside of the device from the natural environment such as rain and wind. A resin material such as PBT resin or PPS resin may be used for the housing 35 and the cover 39.

On the other main surface 12 of the substrate 10, a heat radiating plate 40 for releasing the heat of the substrate 10 is provided.
On the surface of the heat radiating plate 40 on the substrate 10 side, a plurality of support bases 41 are formed at positions corresponding to the plurality of MMIC chips 14 on the substrate 10. The back surface of the heat radiating plate 40 is supported by a base 45 forming the back surface of the radar device 1. The support surface of each support base 41 is in contact with the substrate 10 via the heat radiating sheet S1, and the base 45 is in contact with the heat radiating plate 40 via the heat radiating sheet S2. In the radar device 1, a heat radiating path 40 and a base 45 form a heat radiating path for escaping the heat of the MMIC chip 14. A material having high thermal conductivity such as aluminum may be used for the heat sink 40 and the base 45.

A detailed configuration of the radar device according to the first embodiment will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view of the radar device according to the first embodiment.

As shown in FIG. 2, the MMIC chip 14 is arranged on one main surface 11 of the substrate 10, and the antenna 13 is provided apart from the MMIC chip 14. Further, on one main surface 11 of the substrate 10, a horn 20 having a metal film 28 formed by metal plating on the outer surface of the resin molded body is arranged. A peripheral wall portion 21 surrounding the outer edge of the substrate 10 is provided on the outer peripheral portion of the horn 20, and the peripheral wall portion 21 is formed in a stepped shape so as to avoid the opening edge portion 36 of the housing 35. A horn body 22 on which a waveguide 23 is formed is provided on the inner portion of the horn 20, and a portion corresponding to the MMIC chip 14 and the antenna 13 partially protrudes from the back surface of the horn body 22 on the substrate 10 side.

On the back surface of the horn body 22, a cross-sectional view trap-shaped contact portion 24 that contacts the surface of the MMIC chip 14 is provided at a position corresponding to the MMIC chip 14. Further, on the back surface of the horn main body 22, a thin guide portion 25 projecting along the waveguide 23 is provided at a portion corresponding to the antenna 13. The waveguide 23 is formed by a tapered wall surface 26 of the horn main body 22 and the guide portion 25 so that the facing distance becomes wider as the distance from one main surface 11 of the substrate 10 increases. A lens 30 is arranged on the front surface side of the horn body 22, and a convex lens surface 31 having the center line of the waveguide 23 as the optical axis is formed on the back surface of the lens 30.

A heat radiating plate 40 is provided on the other main surface 12 of the substrate 10. A peripheral wall portion 42 surrounding the outer edge of the substrate 10 is provided on the outer peripheral portion of the heat radiating plate 40, and a support base 41 that contacts the substrate 10 at a portion corresponding to the MMIC chip 14 is provided on the inner portion of the heat radiating plate 40. .. The peripheral wall portion 42 of the heat radiating plate 40 is in contact with the peripheral wall portion 21 of the horn 20, and the support base 41 of the heat radiating plate 40 is in contact with the substrate 10 via the heat radiating sheet S1. The heat radiating plate 40 is supported by the base 45 via the heat radiating sheet S2. Since the base 45 is made of a metal having a high thermal conductivity like the heat sink 40, the base 45 also functions as a heat sink.

Since the outer surface of the horn 20 is covered with the metal film 28, a shield layer 29 that shields radio waves by the metal film 28 is formed on the wall surface of the horn 20 forming the waveguide 23. As a result, the shielding property of the radio wave in the waveguide 23 is ensured, and the directivity and intensity of the radio wave are improved. Further, since the contact portion 24 is in contact with the surface of the MMIC chip 14 via the metal film 28, the heat transfer path R2 from the MMIC chip 14 to the shield layer 29 is formed by the metal film 28, and the MMIC chip is formed. A heat dissipation path R3 from 14 to the heat dissipation plate 40 is formed of the metal film 28. As a result, the occurrence of dew condensation in the waveguide 23 is prevented, and the temperature rise of the MMIC chip 14 is suppressed.

The directivity and intensity of radio waves of the radar device will be described with reference to FIGS. 3A and 3B.
FIG. 3A is an explanatory diagram of a radio wave radiation state according to a comparative example. FIG. 3B is an explanatory diagram of a radio wave radiation state of the first embodiment. The radar device of the comparative example is different from the radar device of the present embodiment only in that the outer surface of the resin horn is not metal-plated.

As shown in FIG. 3A, in the radar device 50 according to the comparative example, when power is supplied from the MMIC chip 53 to the antenna 52, radio waves are radiated from the antenna 52 to the outside. The radio wave from the antenna 52 toward the inside of the waveguide 55 is guided to the lens surface 57 through the waveguide 55, converted into a plane wave on the lens surface 57, and used for detecting an obstacle. The radio wave from the antenna 52 to the outside of the waveguide 55 travels straight inside the resin horn 54 and is emitted to the outside, and is not used for detecting obstacles. Therefore, although the weight of the horn 54 can be reduced, the radio wave utilization efficiency is lowered, and the directivity and intensity of the radio wave are lowered.

On the other hand, as shown in FIG. 3B, in the radar device 1 according to the first embodiment, the shield layer 29 is formed by the metal film 28 on the tapered wall surface 26 of the horn 20 forming the waveguide 23, and the waveguide is formed. The shielding property of 23 is secured. Both the radio wave from the antenna 13 to the inside of the waveguide 23 and the radio wave from the antenna 13 to the outside of the waveguide 23 are guided to the lens surface 31 by the shield layer 29 of the horn 20 and converted into a plane wave by the lens surface 31. Used to detect obstacles. Therefore, the weight of the horn 20 can be reduced, the radio wave utilization efficiency is increased, the directivity and intensity of the radio wave are improved, and the detection accuracy is improved.

The radio wave interference of the radar device will be described with reference to FIGS. 4A and 4B. FIG. 4A is an explanatory diagram of a state of radiation of radio waves by a plurality of antennas according to a comparative example. FIG. 4B is an explanatory diagram of a radio wave radiating state by the plurality of antennas of the first embodiment.

As shown in FIG. 4A, in the radar device 50 according to the comparative example, a plurality of waveguides 55 are formed corresponding to the plurality of antennas 52, and radio waves are radiated from each antenna 52 at the same time. Radio waves from each antenna 52 toward the inside of each waveguide 55 are guided to the lens surface 57 through the waveguide 55, converted into a plane wave on the lens surface 57, and used for detecting obstacles. The radio waves from each antenna 52 toward the outside of each waveguide 55 travel straight through the resin horn 54 and enter the adjacent waveguide 55, causing radio wave interference. Obstacle detection performance deteriorates due to this radio wave interference.

On the other hand, as shown in FIG. 4B, in the radar device 1 according to the first embodiment, even if radio waves are radiated from a plurality of antennas 13 at the same time, the shield layer 29 of the horn 20 allows the radio waves to go out of the waveguide 23. Leakage is prevented. Both the radio waves from the antenna 13 toward the inside of the waveguide 23 and the radio waves from the antenna 13 toward the outside of the waveguide 23 are guided to the lens surface 31 by the shield layer 29 of the horn 20 and converted into a plane wave by the lens surface 31. Used to detect obstacles. Therefore, radio wave interference does not occur between the plurality of waveguides 23, and obstacle detection performance does not deteriorate due to radio wave interference.

The heat transfer path and heat dissipation path of the radar device will be described with reference to FIGS. 5A and 5B.
FIG. 5A is an explanatory diagram of a heat transfer path and a heat dissipation path according to a comparative example. FIG. 5B is an explanatory diagram of a heat transfer path and a heat dissipation path according to the first embodiment.

As shown in FIG. 5A, in the radar device 50 according to the comparative example, when the air inside the device is warmed by the heat generated by the MMIC chip 53, dew condensation 59 is generated on the tapered wall surface 58 of the horn 54 due to the temperature difference between the inside and outside, and the radio wave is transmitted. May be disturbed. Further, the heat generated by the MMIC chip 53 is transmitted to the support base 61 of the heat radiating plate 60 via the substrate 51 and the heat radiating sheet S1, and further transmitted from the heat radiating plate 60 to the base 62 via the heat radiating sheet S2. The temperature rise of the MMIC chip 53 cannot be effectively suppressed only by the heat dissipation path R1 from the MMIC chip 53 in the thickness direction of the substrate 51.

On the other hand, as shown in FIG. 5B, in the radar device 1 according to the first embodiment, a heat transfer path R2 from the MMIC chip 14 to the shield layer 29 is formed on the outer surface of the horn 20.
The heat transfer path R2 is formed by a metal film 28 that covers the outer surface of the horn 20 from the contact portion 24 to the guide portion 25, and the metal film 28 of the heat transfer path R2 and the metal of the shield layer 29 are formed at the tip portion of the guide portion 25. The membranes 28 are connected. The heat generated by the MMIC chip 14 is transmitted to the shield layer 29 through the heat transfer path R2, and the shield layer 29 is warmed to suppress the generation of dew condensation 59. In this way, the heat generated by the MMIC chip 14 is used in order to suppress the occurrence of dew condensation 59 on the waveguide 23.

At this time, the heat generated by the MMIC chip 14 is easily transmitted to the metal film 28 on the outer surface of the horn 20, but since the resin-molded portion of the horn 20 has low thermal conductivity, the resin-molded portion inside the metal film 28 on the outer surface of the horn 20. It is difficult for heat to be transmitted to. Since heat is intensively transferred from the MMIC chip 14 to the metal film 28 having a high thermal conductivity and a small heat capacity, the shield layer 29 can be heated in a short time through the heat transfer path R2 by the heat generated by the MMIC chip 14. Therefore, the shield layer 29 can be warmed immediately after the radar device 1 is started, and the disturbance of the radio wave due to the dew condensation 59 can be effectively suppressed.

Further, in the radar device 1 according to the first embodiment, a heat dissipation path R3 from the MMIC chip 14 to the heat dissipation plate 40 is formed on the outer surface of the horn 20. The heat radiation path R3 is formed by a metal film 28 that covers the outer surface of the horn 20 from the contact portion 24 to the peripheral wall portion 21, and the heat radiation path R3 is formed by the mating surface of the peripheral wall portion 21 of the horn 20 and the peripheral wall portion 42 of the heat radiation plate 40. The metal film 28 is in contact with the heat radiating plate 40. The heat generated by the MMIC chip 14 is transmitted to the peripheral wall portion 42 of the heat radiating plate 40 through the heat radiating path R3, and is transmitted from the heat radiating plate 40 to the base 45 via the heat radiating sheet S2.
In this way, in addition to the heat dissipation path R1 from the MMIC chip 14 in the thickness direction of the substrate 10, the temperature rise of the MMIC chip 14 can be suppressed by the heat dissipation path R3 from the MMIC chip 14 through the outer surface of the horn 20.

Here, the shield layer 29, the heat transfer path R2, and the heat dissipation path R3 are formed of a metal film 28 made of the same material, but the configuration is not limited to this. Even if the shield layer 29 is formed of a metal film having a higher shielding property than the heat transfer path R2 and the heat dissipation path R3, and the heat transfer path R2 and the heat dissipation path R3 are formed of a metal film having a higher thermal conductivity than the shield layer 29. good. For example, nickel having a high shielding property may be used for the shield layer 29, and copper having a high thermal conductivity may be used for the heat transfer path R2 and the heat dissipation path R3. A thickness of 0.021 μm or more is required to secure the shielding property with nickel, and a thickness of 10 μm or more is required to secure the heat transfer property with copper.

Further, when the shield layer 29, the heat transfer path R2, and the heat dissipation path R3 are formed by the same metal film 28, the metal film of the heat transfer path R2 and the heat dissipation path R3 is larger than the wall thickness of the metal film 28 of the shield layer 29. The wall thickness of 28 may be formed to be large. For example, when the shield layer 29, the heat transfer path R2, and the heat dissipation path R3 are formed of a copper film, the shield layer 29 is formed of a copper film having a thickness of 0.24 μm or more, and the heat transfer path R2 and the heat dissipation path R3 are 10 μm. It may be formed of a copper film having a thickness of the above. As a result, the heat generated by the MMIC chip 14 becomes easier to transfer heat from the MMIC chip 14 to the metal film 28 by the amount that the metal film 28 of the heat transfer path R2 and the heat dissipation path R3 becomes thicker. Further, the shield layer 29 may be formed of a plurality of layers, for example, a two-layer structure of nickel having a high shielding property and copper having a high thermal conductivity.

As described above, in the radar device 1 of the first embodiment, the shielding property in the waveguide 23 is ensured by the metal film 28, and the directivity and the radio strength of the radio wave emitted from the waveguide 23 are improved. .. Further, by adopting the resin horn 20, the amount of metal used can be suppressed and the weight of the radar device 1 can be reduced. The heat transfer path R2 passing through the outer surface of the horn 20 makes it possible to suppress the occurrence of dew condensation on the waveguide 23 by utilizing the heat generated by the MMIC chip 14. Further, the heat radiating path R3 passing through the outer surface of the horn 20 allows the heat generated by the MMIC chip 14 to escape to the heat radiating plate 40, so that the temperature rise of the MMIC chip 14 can be suppressed.

In the first embodiment, the heat dissipation path is increased by the metal film 28 on the outer surface of the horn 20, but the heat dissipation path is increased by using the heat dissipation pattern provided on the substrate 10 and the heat dissipation member provided on the MMIC chip 14. You may. Hereinafter, the heat dissipation path of the radar device will be described with reference to the second to ninth embodiments. Further, in the second to ninth embodiments, substantially the same configuration and similar configurations as those of the first embodiment will be described with the same reference numerals.

[Second Embodiment]
FIG. 6 is a schematic cross-sectional view of the radar device of the second embodiment. The radar device of the second embodiment is different from the first embodiment only in a partial configuration of the substrate, the horn, and the heat radiating plate. Therefore, only the heat dissipation path will be mainly described, and the description of the configuration similar to that of the first embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 6, in the radar device 1 according to the second embodiment, the MMIC chip 14 is provided as an electronic component on one main surface 11 of the substrate 10. A heat dissipation path R4 is formed on one main surface 11 of the substrate 10 by a heat dissipation pattern 15 extending from the vicinity of the MMIC chip 14 to the outer edge of the substrate 10. The heat dissipation pattern 15 is electrically separated from the circuit pattern. One end of the heat dissipation pattern 15 is slightly separated from the MMIC chip 14, and the other end of the heat dissipation pattern 15 is in contact with the peripheral wall portion 21 of the horn 20 at the outer edge portion of the substrate 10. The heat dissipation pattern 15 may be formed of a material having high thermal conductivity such as copper or aluminum. Further, the other end of the heat dissipation pattern 15 may extend along the outer edge of the substrate 10.

The MMIC chip 14 is coated with heat-dissipating grease G1 as a semi-solid or gel-like heat-dissipating member, and the MMIC chip 14 is connected to one end of the heat-dissipating pattern 15 via the heat-dissipating grease G1. Further, the other end of the heat radiation pattern 15 is coated with the heat radiation grease G2, and the other end of the heat radiation pattern 15 is connected to the horn 20 via the heat radiation grease G2. The thermal resistance can be reduced by allowing the heat radiating greases G1 and G2 to enter the gap between the MMIC chip 14 and the heat radiating pattern 15 and the gap between the horn 20 and the heat radiating pattern 15. As the heat radiating member, a heat radiating adhesive in which the heat conductive filler is dispersed in an adhesive may be used instead of the heat radiating grease in which the heat conductive filler is dispersed in the grease.

Further, in the horn 20 and the heat radiating plate 40, a heat radiating path R5 is formed by protrusions 27 and 43 protruding from the outer edge of the substrate 10. The protruding portion 27 of the horn 20 protrudes from the peripheral wall portion 21 so as to cover the outer edge portion on one main surface 11 side of the substrate 10, and the protruding portion 43 of the heat radiating plate 40 is the other main surface of the substrate 10. It protrudes from the peripheral wall portion 42 so as to cover the outer edge portion on the 12 side, and the protrusion portion 27 of the horn 20 and the protrusion portion 43 of the heat radiation plate 40 are in contact with each other. The protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are formed along the outer edge portion of the substrate 10, and the horn 20 and the heat radiating plate 40 are in contact with each other in a wide range. The horn 20 and the heat radiating plate 40 may have protruding portions 27 and 43 partially formed along a part of the outer edge portion of the substrate 10.

Depending on the contact state between the protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40, the thermal resistance may increase due to a slight gap between the contact surfaces of the protruding portions 27 and 43. Therefore, the protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are connected via the heat radiating grease G3. As a result, the gap between the contact surface between the protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 is filled with the thermal paste G3, and the thermal resistance between the horn 20 and the heat radiating plate 40 is increased by the thermal paste G3. Can be reduced. When the protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are in contact with each other without a gap, the heat radiating grease G3 is unnecessary.

As described above, in the radar device 1 of the second embodiment, the heat radiation path R4 from the MMIC chip 14 to the horn 20 is formed by the heat radiation pattern 15 and the heat radiation greases G1 and G2. Further, in the radar device 1, a heat dissipation path R5 from the horn 20 to the heat dissipation plate 40 is formed by the protrusions 27 and 43 and the heat dissipation grease G3. As described above, in addition to the heat dissipation path R1 from the MMIC chip 14 toward the thickness of the substrate 10, the heat dissipation paths R4 and R5 form a heat dissipation path having a small thermal resistance. Therefore, the temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths R1, R4, and R5.

[Third Embodiment]
FIG. 7 is a schematic cross-sectional view of the radar device of the third embodiment. The radar device of the third embodiment is different from the second embodiment in that a heat radiating sheet is used instead of the heat radiating grease as the heat radiating member. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 7, in the radar device 1 according to the third embodiment, the heat radiating sheet S3 is attached to the MMIC chip 14, and the MMIC chip 14 is attached to one end of the heat radiating pattern 15 via the heat radiating sheet S3. It is connected. A heat radiating sheet S4 is attached to the other end of the heat radiating pattern 15, and the other end of the heat radiating pattern 15 is connected to the horn 20 via the heat radiating sheet S4. The protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are connected via a heat radiating sheet S5 provided along the outer edge of the substrate 10. As the heat radiating sheet, for example, a sheet material containing a heat conductive filler is used.

As described above, in the radar device 1 of the third embodiment, the heat dissipation path R4 from the MMIC chip 14 to the horn 20 is formed by the heat dissipation pattern 15 and the heat dissipation sheets S3 and S4. Further, in the radar device 1, a heat radiation path R5 from the horn 20 to the heat radiation plate 40 is formed by the protrusions 27 and 43 and the heat radiation sheet S5. In this way, the temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths R1, R4, and R5. Further, the thickness of the heat radiating member can be made constant, and the variation in heat radiating property due to the difference in the thickness of the heat radiating member can be reduced. In addition, it is possible to suppress variations in device dimensions during assembly of the radar device 1.

[Fourth Embodiment]
FIG. 8 is a schematic cross-sectional view of the radar device of the fourth embodiment. The radar device of the fourth embodiment is different from the second embodiment in that a heat dissipation path is formed by a metal plate. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 8, in the radar device 1 according to the fourth embodiment, the heat radiating adhesive A1 is applied to the MMIC chip 14, and the MMIC chip 14 passes through the heat radiating adhesive A1 to one end of the heat radiating pattern 15. It is connected to the. The other end of the heat radiating pattern 15 is coated with the heat radiating grease G2, and the other end of the heat radiating pattern 15 is connected to the horn 20 via the heat radiating grease G2. A heat dissipation path R6 is formed on one main surface 11 of the substrate 10 by a metal plate 19 separated from the main surface 11 in the height direction. The metal plate 19 extends from the upper surface of the MMIC chip 14 to an intermediate portion of the heat dissipation pattern 15 in the extending direction.

One end of the metal plate 19 is supported by the heat-dissipating adhesive A1 on the MMIC chip 14, and the other end of the metal plate 19 is supported by the heat-dissipating adhesive A2 on the heat-dissipating pattern 15. The metal plate 19 may be made of a material having a high thermal conductivity, such as copper or aluminum, as in the heat dissipation pattern 15. The shape and structure of the metal plate 19 are not particularly limited. The protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are connected via a heat radiating grease G3 provided along the outer edge of the substrate 10. In the fourth embodiment, a heat radiating sheet may be used instead of the heat radiating greases G2 and G3.

As described above, in the radar device 1 of the fourth embodiment, in addition to the above-mentioned heat dissipation paths R1, R4, R5, the heat dissipation adhesives A1, A2 and the metal plate 19 move from the MMIC chip 14 to the heat dissipation pattern 15. The heat dissipation path R6 is formed. The temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths R1 and R4-R6.

[Fifth Embodiment]
FIG. 9 is a schematic cross-sectional view of the radar device of the fifth embodiment. The radar device of the fifth embodiment is different from the second embodiment in that a heat dissipation path is formed by a wall portion. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 9, the radar device 1 according to the fifth embodiment is formed in an annular shape so that one end side of the heat dissipation pattern 15 surrounds the MMIC chip 14. A heat-dissipating grease G1 is applied to the MMIC chip 14, and the heat-dissipating pattern 15 is connected to the annular portion of the MMIC chip 14 via the heat-dissipating grease G1. The other end of the heat radiating pattern 15 is coated with the heat radiating grease G2, and the other end of the heat radiating pattern 15 is connected to the peripheral wall portion 21 of the horn 20 via the heat radiating grease G2. In the horn 20, a heat dissipation path R7 is formed by a wall portion 33 surrounding the MMIC chip 14.

The wall portion 33 projects from the back surface of the horn 20 on the substrate 10 side and is connected to the annular portion of the heat dissipation pattern 15 via the heat radiation grease G4. The cross-sectional shape of the wall portion 33 in a plan view is not limited to the annular shape, and may be any shape that can surround the MMIC chip 14. Similarly, the annular portion of the heat dissipation pattern 15 is not limited to the annular shape, and may be any shape that can surround the MMIC chip 14. Further, the protruding portion 27 of the horn 20 and the protruding portion 43 of the heat radiating plate 40 are connected via a heat radiating grease G3 provided along the outer edge of the substrate 10. In the fifth embodiment, a heat radiating sheet may be used instead of the heat radiating grease G1-G4.

As described above, in the radar device 1 of the fifth embodiment, in addition to the above-mentioned heat dissipation paths R1, R4, and R5, heat is dissipated from one end of the heat dissipation pattern 15 toward the horn 20 by the thermal paste G4 and the wall portion 33. Path R7 is formed. The temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths R1, R4, R5, and R7.

[Sixth Embodiment]
FIG. 10 is a schematic cross-sectional view of the radar device of the sixth embodiment. The radar device of the sixth embodiment is different from the second embodiment in that a heat dissipation path is formed by heat dissipation vias. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 10, in the radar device 1 according to the sixth embodiment, the thermal paste G1 is applied to the MMIC chip 14 on one main surface 11 of the substrate 10, and the MMIC chip 14 applies the thermal paste G1. It is connected to one end of the heat dissipation pattern 15 via. The other end of the heat radiating pattern 15 is coated with the heat radiating grease G2, and the other end of the heat radiating pattern 15 is connected to the horn 20 via the heat radiating grease G2. A heat dissipation pattern 16 is formed on the other main surface 12 of the substrate 10 along the outer edge of the substrate 10, and the heat dissipation pattern 16 is connected to the heat dissipation plate 40 via the thermal paste G5.

A heat dissipation path R8 is formed on the outer edge of the substrate 10 by a conductive heat dissipation via 17 that penetrates the substrate 10 in the thickness direction and connects the heat dissipation pattern 15 and the heat dissipation pattern 16. As described above, instead of forming the heat dissipation path by the protruding portion of the horn 20 and the heat dissipation plate 40, the device can be miniaturized by forming the heat dissipation path by the heat dissipation via 17. The heat dissipation pattern 15 is not limited to the configuration in which the heat dissipation patterns 15 and 16 are provided on one main surface 11 and the other main surface 12, and the heat dissipation pattern 15 may be provided only on one main surface 11. In the sixth embodiment, a heat radiating sheet may be used instead of the heat radiating greases G1, G2, and G5.

As described above, in the radar device 1 of the sixth embodiment, in addition to the heat radiation paths R1 and R4 described above, a heat radiation path R8 from the horn 20 to the heat radiation plate 40 is formed by the heat radiation via 17. The temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths R1, R4, and R8. The heat radiating via 17 may be formed so that the horn 20 and the heat radiating plate 40 can be connected, and the heat radiating via 17 may not be connected to the heat radiating patterns 15 and 16.

[7th Embodiment]
FIG. 11 is a schematic cross-sectional view of the radar device of the seventh embodiment. The radar device of the seventh embodiment is different from the second embodiment in that the heat dissipation pattern is covered with a resist layer except for a part. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 11, in the radar device 1 according to the seventh embodiment, the heat dissipation pattern 15 is covered with a resist layer 18 except for both ends. A heat-dissipating grease G1 is applied to the MMIC chip 14, and the MMIC chip 14 is connected to one end (exposed portion) of the heat-dissipating pattern 15 exposed from the resist layer 18 via the heat-dissipating grease G1. Further, the heat radiating grease G2 is applied to the other end (exposed part) of the heat radiating pattern 15 exposed from the resist layer 18, and the other end of the heat radiating pattern 15 is connected to the horn 20 via the heat radiating grease G2. .. The heat dissipation path of the seventh embodiment is the same as that of the second embodiment.

As described above, in the radar device 1 of the sixth embodiment, the temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths. Even if the heat dissipation pattern 15 is covered with the resist layer 18, it is possible to form a heat dissipation path having a small thermal resistance.

[8th Embodiment]
FIG. 12 is a schematic cross-sectional view of the radar device of the eighth embodiment. The radar device of the eighth embodiment is different from the second embodiment in that the horn is provided with a contact portion that abuts on the MMIC chip. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 12, in the radar device 1 according to the eighth embodiment, the contact portion 24 of the horn 20 is in contact with the surface of the MMIC chip 14 via the heat radiation grease G1. Therefore, the horn 20 is formed with a heat transfer path R2 from the MMIC chip 14 to the shield layer (see FIG. 1) and a heat transfer path R3 from the MMIC chip 14 to the heat sink 40. Further, in the radar device 1 according to the eighth embodiment, heat dissipation paths R1, R4, and R5 are formed as in the second embodiment. Therefore, the occurrence of dew condensation in the waveguide is prevented, and the temperature rise of the MMIC chip 14 is suppressed.

As described above, in the radar device 1 of the seventh embodiment, the temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths. Further, by increasing the heat dissipation path, even if the metal film plated on the outer surface of the resin horn 20 is thinly formed, the temperature rise of the MMIC chip 14 can be suppressed to a specified temperature.

[9th Embodiment]
FIG. 13 is a schematic cross-sectional view of the radar device of the ninth embodiment. The radar device of the ninth embodiment is different from the second embodiment in that a metal horn is used. Therefore, the description of the configuration similar to that of the second embodiment will be omitted as much as possible. Here, the heat dissipation path of the MMIC chip will be described, but the heat dissipation path of the following embodiment can also be applied to the heat dissipation of other electronic components.

As shown in FIG. 13, in the radar device 1 according to the ninth embodiment, the horn 20 is made of a material having high shielding properties and thermal conductivity such as aluminum. Further, in the radar device 1 according to the ninth embodiment, heat dissipation paths R1, R4, and R5 are formed as in the second embodiment. Even with such a configuration, the temperature rise of the MMIC chip 14 can be effectively suppressed by the plurality of heat dissipation paths. Further, by using a metal horn 20 having a large heat capacity, the heat dissipation of the MMIC chip 14 can be improved.

In each of the above-described embodiments, a plurality of antennas 13 are provided on the substrate 10 and a plurality of waveguides 23 are formed on the horn 20, but a single antenna 13 is provided on the substrate 10 and the horn. A single waveguide 23 may be formed in 20.

Further, in each of the above-described embodiments, the metal film 28 is formed on the entire outer surface of the horn 20, and the shield layer 29, the heat transfer path R2, and the heat dissipation path R3 are formed, but the configuration is not limited to this. A metal film 28 may be partially formed on the outer surface of the horn 20, and a shield layer 29, a heat transfer path R2, and a heat dissipation path R3 may be formed.

As described above, the radar device (1) described in the present embodiment has a substrate (10) in which an electronic component (MMIC chip 14) is provided on one main surface (11) and one main substrate (10). A radar device (1) including a horn (20) arranged on a surface (11) and a heat sink (40) provided on the other main surface (12) of a substrate (10). A heat dissipation pattern (15) is formed on one main surface (11) of (10), and the electronic component (MMIC chip 14) is a first heat dissipation member (heat dissipation grease G1, heat dissipation sheet S1, heat dissipation adhesive A1). ), And the horn (20) is connected to the heat dissipation pattern (15) via the second heat dissipation member (heat dissipation grease G2, heat dissipation sheet S2).

According to this configuration, the electronic component (MMIC chip 14) is connected to the heat dissipation pattern (15) via the heat dissipation member (heat dissipation grease G1, heat dissipation sheet S1, heat dissipation adhesive A1), and the heat dissipation pattern (15) is the heat dissipation member. It is connected to the horn (20) via (heat dissipation grease G2, heat dissipation sheet S2). Therefore, in addition to the heat dissipation path (R1) in the thickness direction of the substrate (10) from the electronic component (MMIC chip 14) to the heat sink (40), the thermal resistance from the electronic component (MMIC chip 14) to the horn (20). A small heat dissipation path (R4) is formed. The temperature rise of the electronic component (MMIC chip 14) can be effectively suppressed by the plurality of heat dissipation paths.

In the radar device (1) according to the present embodiment, the first heat radiating member and the second heat radiating member are semi-solid or gel-shaped heat radiating members (heat radiating greases G1, G2, heat radiating adhesive A1).

According to this configuration, the semi-solid or gel-like heat-dissipating member (heat-dissipating grease G1, G2, heat-dissipating adhesive A1) dissipates heat from the gap between the electronic component (MMIC chip 14) and the heat-dissipating pattern (15) or the horn (20). Since it enters the gap of the pattern (15), the thermal resistance can be reduced.

In the radar device (1) according to the present embodiment, the semi-solid or gel-like heat-dissipating member is a heat-dissipating grease (G1-G5) or a heat-dissipating adhesive (A1, A2).

According to this configuration, the gap between the members can be filled with the heat radiating grease (G1-G5) or the heat radiating adhesive (A1, A2).

In the radar device (1) described in the present embodiment, the first heat radiating member and the second heat radiating member are heat radiating sheets (S3-S5).

According to this configuration, the thickness of the heat radiating member can be made constant, and the variation in heat radiating property due to the difference in the thickness of the heat radiating member can be reduced. Further, since the heat radiating sheet (S3-S5) is sandwiched between the horn (20) and the substrate (10), it is possible to suppress variations in the device dimensions during assembly.

In the radar device (1) according to the present embodiment, the horn (20) and the heat radiating plate (40) have protrusions (27, 43) protruding from the outer edge of the substrate (10), and the horn (27, 43). The protruding portion (27) of 20) and the protruding portion (43) of the heat radiating plate (40) are in contact with each other.

According to this configuration, a heat dissipation path (R5) from the horn (20) to the heat dissipation plate (40) is formed. By increasing the heat dissipation path, it is possible to more effectively suppress the temperature rise of the electronic component (MMIC chip 14).

In the radar device (1) according to the present embodiment, the protruding portion (27) of the horn (20) and the protruding portion (43) of the heat radiating plate (40) are aligned along the outer edge of the substrate (10). It is formed.

According to this configuration, the heat dissipation path (R5) can be formed in a wide range around the substrate (10).

In the radar device (1) according to the present embodiment, the protruding portion (27) of the horn (20) and the protruding portion (43) of the heat radiating plate (40) are in a semi-solid or gel-like third state. It is connected via a heat radiating member (heat radiating gel G3).

According to this configuration, a slight gap between the contact surfaces of the protruding portion (27) of the horn (20) and the protruding portion (43) of the heat radiating plate (40) is filled with a heat radiating member to reduce the thermal resistance. Can be done.

In the radar device (1) described in this embodiment, a metal plate (19) is provided so as to be separated from one main surface (11) of the substrate (10) in the height direction, and the metal plate (19) is provided. It is supported by a first heat-dissipating member (radiating adhesive A1) on an electronic component (MMIC chip 14) and a fourth heat-dissipating member (radiating adhesive A2) on a heat-dissipating pattern (15).

According to this configuration, a heat dissipation path (15) from the electronic component (MMIC chip 14) to the heat dissipation pattern (15) via the metal plate (19) at a position separated from one main surface (11) of the substrate (10). R6) is formed. By increasing the heat dissipation path, it is possible to more effectively suppress the temperature rise of the electronic component (MMIC chip 14).

In the radar device (1) described in the present embodiment, the horn (20) is provided with a wall portion (33) surrounding the electronic component (MMIC chip 14), and the wall portion (33) is a fifth heat radiating member. It is connected to the heat dissipation pattern (15) via (heat dissipation grease G4).

According to this configuration, a heat dissipation path (R7) is formed from the heat dissipation pattern (15) to the horn (20) via the wall portion (33). By increasing the heat dissipation path, it is possible to more effectively suppress the temperature rise of the electronic component (MMIC chip 14).

In the radar device (1) described in the present embodiment, a heat radiating via (17) penetrating the board (10) in the thickness direction is provided on the outer edge of the board (10), and the horn (20) is a heat radiating via (20). It is connected to the heat radiating plate (40) via 17).

According to this configuration, a heat dissipation path (R8) from the horn (20) to the heat dissipation plate (40) is formed via the heat dissipation via (17). By increasing the heat dissipation path, it is possible to more effectively suppress the temperature rise of the electronic component (MMIC chip 14). Further, since it is not necessary to form a protruding portion on the horn (20) and the heat radiating plate (40), the size of the device can be reduced.

In the radar device (1) described in the present embodiment, the heat dissipation pattern (15) is covered with the resist layer (18) except for a part, and the electronic component (MMIC chip 14) is the first heat dissipation member (heat dissipation). It is connected to the exposed portion of the heat dissipation pattern (15) exposed from the resist layer (18) via the grease G1, the heat dissipation sheet S1, and the heat dissipation adhesive A1), and the horn (20) is connected to the second heat dissipation member (heat dissipation grease). It is connected to another exposed portion of the heat dissipation pattern (15) exposed from the resist layer (18) via G2 and the heat dissipation sheet S2).

According to this configuration, the thermal resistance of the electronic component (MMIC chip 14) and the heat dissipation pattern (15) and the thermal resistance of the heat dissipation pattern (15) and the horn (20) are reduced to form a heat dissipation path having a small thermal resistance. Can be done.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs are designed without departing from the spirit of the present invention described in the claims. You can make changes. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add / delete / replace other configurations with respect to a part of the configurations of each embodiment.

1 Radar device 10 Board 11 One main surface 12 The other main surface 14 MMIC chip (electronic component)
15 Heat dissipation pattern 17 Heat dissipation via 18 Resist layer 19 Metal plate 20 Horn 27 Overhang 33 Wall 40 Heat dissipation plate 43 Overhang 45 Base A1 Thermal adhesive A2 Thermal adhesive G1-G5 Thermal grease R1-R8 Thermal path S1-S5 Thermal paste sheet

Claims (11)

A radar device including a substrate provided with electronic components on one main surface, a horn arranged on one main surface of the substrate, and a heat radiating plate provided on the other main surface of the substrate. hand,
A heat dissipation pattern is formed on one main surface of the substrate, the electronic component is connected to the heat dissipation pattern via the first heat dissipation member, and the horn dissipates heat through the second heat dissipation member. A radar device characterized by being connected to a pattern. The radar device according to claim 1, wherein the first heat radiating member and the second heat radiating member are semi-solid or gel heat radiating members. The radar device according to claim 2, wherein the semi-solid or gel-like heat-dissipating member is a heat-dissipating grease or a heat-dissipating adhesive. The radar device according to claim 1, wherein the first heat radiating member and the second heat radiating member are heat radiating sheets. The horn and the heat radiating plate have a protruding portion protruding from the outer edge of the substrate.
The radar device according to claim 1, wherein the protruding portion of the horn and the protruding portion of the heat radiating plate are in contact with each other. The radar device according to claim 5, wherein the protruding portion of the horn and the protruding portion of the heat radiating plate are formed along the outer edge of the substrate. The radar device according to claim 5, wherein the protruding portion of the horn and the protruding portion of the heat radiating plate are connected via a semi-solid or gel-like third heat radiating member. A metal plate is provided so as to be separated from one main surface of the substrate in the height direction, and the metal plate is formed by the first heat radiating member on the electronic component and the fourth heat radiating member on the heat radiating pattern. The radar device according to claim 1, wherein the radar device is supported. The radar device according to claim 1, wherein the horn is provided with a wall portion surrounding the electronic component, and the wall portion is connected to the heat radiation pattern via a fifth heat radiation member. A heat radiating via that penetrates the substrate in the thickness direction is provided on the outer edge of the substrate.
The radar device according to claim 1, wherein the horn is connected to the heat radiating plate via the heat radiating via. The heat dissipation pattern is covered with a resist layer except for a part, and the electronic component is connected to an exposed portion of the heat dissipation pattern exposed from the resist layer via the first heat dissipation member, and the horn. The radar device according to any one of claims 1 to 10, wherein the radar device is connected to another exposed portion of the heat dissipation pattern exposed from the resist layer via the second heat dissipation member.

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