CN111182713A - High-frequency circuit board and manufacturing method thereof - Google Patents

High-frequency circuit board and manufacturing method thereof Download PDF

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Publication number
CN111182713A
CN111182713A CN202010040716.XA CN202010040716A CN111182713A CN 111182713 A CN111182713 A CN 111182713A CN 202010040716 A CN202010040716 A CN 202010040716A CN 111182713 A CN111182713 A CN 111182713A
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CN
China
Prior art keywords
layer
circuit
circuit layer
antenna
circuit board
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Pending
Application number
CN202010040716.XA
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Chinese (zh)
Inventor
徐颖龙
张昕
虞成城
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Shenzhen Sunway Communication Co Ltd
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Shenzhen Sunway Communication Co Ltd
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Publication date
Application filed by Shenzhen Sunway Communication Co Ltd filed Critical Shenzhen Sunway Communication Co Ltd
Priority to CN202010040716.XA priority Critical patent/CN111182713A/en
Publication of CN111182713A publication Critical patent/CN111182713A/en
Pending legal-status Critical Current

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/0213—Electrical arrangements not otherwise provided for
    • H05K1/0237—High frequency adaptations
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00—Printed circuits
    • H05K1/02—Details
    • H05K1/11—Printed elements for providing electric connections to or between printed circuits
    • H05K1/115—Via connections; Lands around holes or via connections
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
    • H05K3/42—Plated through-holes or plated via connections
    • H05K3/429—Plated through-holes specially for multilayer circuits, e.g. having connections to inner circuit layers

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Parts Printed On Printed Circuit Boards (AREA)

Abstract

The invention discloses a high-frequency circuit board and a manufacturing method thereof, wherein the high-frequency circuit board comprises a first antenna layer, a first substrate layer, a second circuit layer and a third circuit layer which are sequentially stacked, first conical holes are arranged on the first substrate layer and the second circuit layer, the small end of each first conical hole is arranged close to the first antenna layer, a first conductive medium is arranged in each first conical hole, and the first antenna layer is conducted with the second circuit layer through the first conductive medium; the second circuit layer is connected with the third circuit layer in a welding mode. The first antenna layer and the second circuit layer of the high-frequency circuit board are conducted in an electroless plating mode, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the base material not damaged, the manufactured antenna is higher in size precision, and the quality of the antenna and the yield of the circuit board can be improved.

Description

High-frequency circuit board and manufacturing method thereof
Technical Field
The invention relates to the technical field of circuit boards, in particular to a high-frequency circuit board and a manufacturing method thereof.
Background
With the rapid development of applications such as automated driving, intelligent factories, smart homes and the like, the demand of high-frequency radar sensors is rapidly increased, and higher requirements are also put forward on high-frequency circuit boards serving as carriers. The conventional method for manufacturing the high-frequency circuit board needs to manufacture a coating on the outer layer, wherein the processing flows such as electroplating, resin filling, grinding and brushing and the like can cause the uniformity of the copper thickness of the outer layer to be poor and the roughness to be large. Further, the manufacturing accuracy of the outer-layer antenna size is affected, and finally the performance of the high-frequency antenna, such as resonant frequency, gain and impedance, is affected. In addition, the via holes on the bonding pads can cause the flatness of the copper surface to be poor, and the yield of the welded chip is affected, so that the conventional manufacturing method of the high-frequency circuit board cannot meet the requirement.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the high-frequency circuit board and the manufacturing method thereof are provided, and the uniformity and the flatness of the copper foil of the antenna layer are good.
In order to solve the technical problems, the invention adopts the technical scheme that:
a high-frequency circuit board comprises a first antenna layer, a first substrate layer, a second circuit layer and a third circuit layer which are sequentially stacked, wherein first conical holes are formed in the first substrate layer and the second circuit layer, small ends of the first conical holes are arranged close to the first antenna layer, first conductive media are arranged in the first conical holes, and the first antenna layer is conducted with the second circuit layer through the first conductive media; the second circuit layer is connected with the third circuit layer in a welding mode.
Further, a second substrate layer, a fourth circuit layer, a third substrate layer, a fifth circuit layer, a fourth substrate layer and a sixth circuit layer are sequentially arranged on a side face, far away from the second circuit layer, of the third circuit layer, a through hole is formed between the third circuit layer and the sixth circuit layer, an electroplated layer is arranged at the position of the through hole, and the third circuit layer, the fourth circuit layer, the fifth circuit layer and the sixth circuit layer are conducted through the electroplated layer.
Furthermore, an ink layer is arranged on one side surface of the sixth circuit layer, which is far away from the fifth circuit layer.
Further, a seventh line layer, a fifth substrate layer and an eighth antenna layer are sequentially arranged on a side face, away from the fifth line layer, of the sixth line layer, second conical holes are formed in the seventh line layer and the fifth substrate layer, small ends of the second conical holes are close to the eighth antenna layer, second conductive media are arranged in the second conical holes, the seventh line layer passes through the second conductive media and the eighth antenna layer are conducted, and the seventh line layer is connected with the sixth line layer in a welded mode.
Furthermore, the material of the first base material layer is FR4, PTFE or LCP.
Furthermore, the welding medium for welding connection of the second circuit layer and the third circuit layer is solder paste or conductive adhesive.
Furthermore, an electroplated layer and an ink layer are sequentially arranged on one side face, far away from the second base material layer, of the third circuit layer.
The invention adopts another technical scheme that:
the manufacturing method of the high-frequency circuit board comprises the steps of respectively manufacturing a first antenna layer and a second circuit layer on two sides of a double-sided copper-clad plate, then drilling from the second circuit layer to the first antenna layer to obtain a first conical hole, wherein the small end of the first conical hole is arranged close to the first antenna layer; filling a first conductive medium in the first conical hole to enable the first antenna layer to be conducted with the second circuit layer; and manufacturing a third circuit layer, and then welding and conducting the second circuit layer and the third circuit layer.
Further, after filling the first tapered hole with a first conductive medium to conduct the first antenna layer and the second circuit layer, the method further includes: and spraying ink on two surfaces of the double-sided copper-clad plate.
Further, a laser drill is used for drilling.
The invention has the beneficial effects that: the first antenna layer and the second circuit layer are conducted in an electroless plating mode, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the base material not to be damaged, the manufactured antenna is higher in size precision, and the quality of the antenna and the yield of the circuit board can be improved.
Drawings
Fig. 1 is a sectional view of a high-frequency circuit board according to a first embodiment of the present invention;
FIG. 2 is a broken view of a double-sided copper-clad plate according to a first embodiment of the present invention;
fig. 3 is a cross-sectional view of a high-frequency circuit board according to a first embodiment of the invention during a manufacturing process;
fig. 4 is another cross-sectional view of the high-frequency circuit board according to the first embodiment of the invention during the manufacturing process;
fig. 5 is another cross-sectional view of the high-frequency circuit board according to the first embodiment of the invention during the manufacturing process;
fig. 6 is another cross-sectional view of the high-frequency circuit board according to the first embodiment of the invention during the manufacturing process;
fig. 7 is another cross-sectional view of the high-frequency circuit board according to the first embodiment of the invention during the manufacturing process;
fig. 8 is another cross-sectional view of the high-frequency circuit board according to the first embodiment of the invention;
fig. 9 is a sectional view of a high-frequency wiring board according to a second embodiment of the present invention.
Description of reference numerals:
1. a first antenna layer; 2. a first base material layer; 3. a second circuit layer; 4. a third circuit layer; 5. a first conductive medium; 6. a second substrate layer; 7. a fourth line layer; 8. a third substrate layer; 9. a fifth circuit layer; 10. a fourth substrate layer; 11. a sixth wiring layer; 12. electroplating layer; 13. an ink layer; 14. a seventh wiring layer; 15. a fifth base material layer; 16. an eighth antenna layer; 17. a second conductive medium; 18. a double-sided copper-clad plate; 19. a first tapered bore.
Detailed Description
In order to explain technical contents, achieved objects, and effects of the present invention in detail, the following description is made with reference to the accompanying drawings in combination with the embodiments.
The most key concept of the invention is as follows: the first antenna layer and the second circuit layer are conducted in an electroless plating mode, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the base material from being damaged.
Referring to fig. 1 to 9, a high-frequency circuit board includes a first antenna layer 1, a first substrate layer 2, a second circuit layer 3, and a third circuit layer 4, which are sequentially stacked, wherein first tapered holes 19 are formed in the first substrate layer 2 and the second circuit layer 3, small ends of the first tapered holes 19 are disposed near the first antenna layer 1, first conductive media 5 are disposed in the first tapered holes 19, and the first antenna layer 1 is conducted with the second circuit layer 3 through the first conductive media 5; the second circuit layer 3 is connected with the third circuit layer 4 by welding.
From the above description, the beneficial effects of the present invention are: the first antenna layer and the second circuit layer are conducted in an electroless plating mode, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the base material not to be damaged, the manufactured antenna is higher in size precision, and the quality of the antenna and the yield of the circuit board can be improved.
Further, a second substrate layer 6, a fourth circuit layer 7, a third substrate layer 8, a fifth circuit layer 9, a fourth substrate layer 10 and a sixth circuit layer 11 are sequentially arranged on a side face, away from the second circuit layer 3, of the third circuit layer 4, a through hole is formed between the third circuit layer 4 and the sixth circuit layer 11, a plating layer 12 is arranged at the through hole, and the third circuit layer 4, the fourth circuit layer 7, the fifth circuit layer 9 and the sixth circuit layer 11 are communicated through the plating layer 12.
As can be seen from the above description, the third to sixth circuit layers are conventional four-layer boards, and the adjacent two circuit layers are electrically connected through the plating layer.
Further, an ink layer 13 is disposed on a side of the sixth circuit layer 11 away from the fifth circuit layer 9.
Further, a seventh line layer 14, a fifth substrate layer 15 and an eighth antenna layer 16 are sequentially arranged on a side face, away from the fifth line layer 9, of the sixth line layer 11, second taper holes are formed in the seventh line layer 14 and the fifth substrate layer 15, small ends of the second taper holes are close to the eighth antenna layer 16, a second conductive medium 17 is arranged in the second taper holes, the seventh line layer 14 is communicated with the eighth antenna layer 16 through the second conductive medium 17, and the seventh line layer 14 is connected with the sixth line layer 11 in a welded mode.
As is apparent from the above description, the antenna layers may be provided on both sides of the high-frequency circuit board.
Further, the material of the first base material layer 2 is FR4, PTFE or LCP.
As can be seen from the above description, the material of the substrate layer can be selected as required.
Further, a welding medium for welding connection of the second circuit layer 3 and the third circuit layer 4 is solder paste or conductive adhesive.
As can be seen from the above description, the welding medium can be selected as desired.
Furthermore, an electroplated layer 12 and an ink layer 13 are sequentially arranged on one side surface of the third circuit layer 4 away from the second substrate layer 6.
The invention adopts another technical scheme that:
the manufacturing method of the high-frequency circuit board comprises the steps of respectively manufacturing a first antenna layer 1 and a second circuit layer 3 on two sides of a double-sided copper-clad plate 18, then drilling from the second circuit layer 3 to the first antenna layer 1 to obtain a first conical hole 19, and arranging the small end of the first conical hole 19 close to the first antenna layer 1; filling the first tapered hole 19 with a first conductive medium 5 to make the first antenna layer 1 and the second circuit layer 3 be conducted; and manufacturing a third circuit layer 4, and then welding and conducting the second circuit layer 3 and the third circuit layer 4.
According to the description, the first antenna layer and the second circuit layer are manufactured separately, and the first antenna layer and the second circuit layer are conducted in an electroless plating mode, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the base material not damaged. The manufacturing method of the high-frequency circuit board is simple and low in manufacturing cost.
Further, after the first conductive medium 5 is filled in the first tapered hole 19 to make the first antenna layer 1 and the second circuit layer 3 conductive, the method further includes: and (3) spraying ink on two sides of the double-sided copper-clad plate 18.
As is apparent from the above description, the sprayed ink can protect the wiring board and can prevent short-circuiting from being caused.
Further, a laser drill is used for drilling.
As can be seen from the above description, the precision of drilling with a laser drill is high.
Example one
Referring to fig. 1 to 8, a first embodiment of the present invention is:
the utility model provides a high frequency circuit board, as shown in fig. 1, includes first antenna layer 1, first substrate layer 2, second circuit layer 3 and the third circuit layer 4 that stacks gradually the setting, be equipped with first bell mouth on first substrate layer 2 and the second circuit layer 3, the tip of first bell mouth is close to first antenna layer 1 sets up, be equipped with first conductive medium 5 in the first bell mouth, first antenna layer 1 passes through first conductive medium 5 with second circuit layer 3 switches on. The second circuit layer 3 is connected with the third circuit layer 4 in a welding mode, and a welding medium for welding the second circuit layer 3 with the third circuit layer 4 is solder paste or conductive adhesive. In this embodiment, a second substrate layer 6, a fourth circuit layer 7, a third substrate layer 8, a fifth circuit layer 9, a fourth substrate layer 10, and a sixth circuit layer 11 are sequentially disposed on a side of the third circuit layer 4 away from the second circuit layer 3, a through hole is disposed between the third circuit layer 4 and the sixth circuit layer 11, an electroplated layer 12 is disposed at the through hole, and the third circuit layer 4, the fourth circuit layer 7, the fifth circuit layer 9, and the sixth circuit layer 11 are conducted through the electroplated layer 12. In the present embodiment, the third wiring layer 4 to the sixth wiring layer 11 have a conventional four-layer board structure. And an ink layer 13 is arranged on one side surface of the sixth circuit layer 11 away from the fifth circuit layer 9. An electroplated layer 12 is further arranged on one side surface of the sixth circuit layer 11 away from the fifth circuit layer 9, and the electroplated layer 12 can be protected by the ink layer 13. And an electroplated layer 12 and an ink layer 13 are sequentially arranged on one side surface of the third circuit layer 4 away from the second base material layer 6. In this embodiment, the material of the first substrate layer 2, the second substrate layer 6, the third substrate layer 8, and the fourth substrate layer 10 is FR4, PTFE, or LCP.
The manufacturing method of the high-frequency circuit board comprises the following steps:
as shown in fig. 2, the double-sided copper-clad plate 18 is first cut into pieces and cut into required specifications.
As shown in fig. 3, the first antenna layer 1 and the second circuit layer 3 are respectively manufactured on two sides of the double-sided copper-clad plate 18, and the line directions of the first antenna layer 1 and the second circuit layer 3 can be set as required.
As shown in fig. 4, a hole is drilled from the second circuit layer 3 in the direction of the first antenna layer 1, resulting in a first tapered hole 19, the small end of the first tapered hole 19 being arranged close to the first antenna layer 1. The number of the holes can be set according to needs, in the embodiment, the number of the holes is two, and a laser drilling machine is adopted for drilling.
As shown in fig. 5, the first tapered hole 19 is filled with a first conductive medium 5 to make the first antenna layer 1 and the second circuit layer 3 electrically connected.
As shown in fig. 6, ink is sprayed on both sides of the double-sided copper-clad plate 18 to obtain an ink layer 13.
As shown in fig. 7, the third circuit layer 4 is fabricated, and in this embodiment, the third circuit layer 4 to the sixth circuit layer 11 can be fabricated together, which is a conventional four-layer board fabrication method. And then the second circuit layer 3 and the third circuit layer 4 are welded and conducted, so that the structure shown in fig. 1 is obtained.
In this embodiment, a high-frequency circuit board structure as shown in fig. 8 can be produced, and fig. 8 is an inverted state of fig. 1.
Example two
Referring to fig. 9, a second embodiment of the present invention is: a high-frequency circuit board is different from the first embodiment in that: sixth circuit layer 11 is equipped with seventh circuit layer 14, fifth substrate layer 15 and eighth antenna layer 16 on keeping away from the side of fifth circuit layer 9 in proper order, be equipped with the second taper hole on seventh circuit layer 14 and the fifth substrate layer 15, the little end in second taper hole is close to eighth antenna layer 16 sets up, be equipped with second conducting medium 17 in the second taper hole, seventh circuit layer 14 passes through second conducting medium 17 with eighth antenna layer 16 switches on, seventh circuit layer 14 with sixth circuit layer 11 welded connection. The high-frequency circuit board in this embodiment is a symmetric structure, that is, antenna layers are disposed on both sides of the circuit board.
In summary, according to the high-frequency circuit board and the manufacturing method thereof provided by the invention, the first antenna layer and the second circuit layer of the high-frequency circuit board are conducted in an electroless plating manner, so that the uniformity, the roughness and the flatness of the copper foil of the first antenna layer can keep the characteristics of the substrate from being damaged, the manufactured antenna has higher dimensional accuracy, and the antenna quality and the yield of the circuit board can be improved.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent changes made by using the contents of the present specification and the drawings, or applied directly or indirectly to the related technical fields, are included in the scope of the present invention.

Claims (10)

1. A high-frequency circuit board is characterized by comprising a first antenna layer, a first substrate layer, a second circuit layer and a third circuit layer which are sequentially stacked, wherein first conical holes are formed in the first substrate layer and the second circuit layer, small ends of the first conical holes are arranged close to the first antenna layer, first conductive media are arranged in the first conical holes, and the first antenna layer is conducted with the second circuit layer through the first conductive media; the second circuit layer is connected with the third circuit layer in a welding mode.
2. The high-frequency circuit board according to claim 1, wherein a second substrate layer, a fourth circuit layer, a third substrate layer, a fifth circuit layer, a fourth substrate layer and a sixth circuit layer are sequentially arranged on a side surface of the third circuit layer away from the second circuit layer, a through hole is arranged between the third circuit layer and the sixth circuit layer, a plating layer is arranged at the through hole, and the third circuit layer, the fourth circuit layer, the fifth circuit layer and the sixth circuit layer are conducted through the plating layer.
3. The high-frequency circuit board according to claim 2, wherein an ink layer is disposed on a side of the sixth circuit layer away from the fifth circuit layer.
4. The high-frequency circuit board according to claim 2, wherein a seventh circuit layer, a fifth substrate layer and an eighth antenna layer are sequentially disposed on a side surface of the sixth circuit layer away from the fifth circuit layer, second tapered holes are disposed on the seventh circuit layer and the fifth substrate layer, small ends of the second tapered holes are disposed near the eighth antenna layer, a second conductive medium is disposed in the second tapered holes, the seventh circuit layer is conducted with the eighth antenna layer through the second conductive medium, and the seventh circuit layer is welded to the sixth circuit layer.
5. The high-frequency circuit board according to claim 1, wherein the material of the first substrate layer is FR4, PTFE or LCP.
6. The high-frequency wiring board according to claim 1, wherein a soldering medium for soldering connection of the second wiring layer and the third wiring layer is solder paste or conductive paste.
7. The high-frequency circuit board according to claim 2, wherein a plating layer and an ink layer are further provided on a side of the third circuit layer away from the second substrate layer in this order.
8. The manufacturing method of the high-frequency circuit board is characterized in that a first antenna layer and a second circuit layer are respectively manufactured on two sides of a double-sided copper-clad plate, then, drilling is carried out from the second circuit layer to the first antenna layer to obtain a first conical hole, and the small end of the first conical hole is arranged close to the first antenna layer; filling a first conductive medium in the first conical hole to enable the first antenna layer to be conducted with the second circuit layer; and manufacturing a third circuit layer, and then welding and conducting the second circuit layer and the third circuit layer.
9. The method for manufacturing a high-frequency circuit board according to claim 8, wherein the step of filling the first tapered hole with the first conductive medium to conduct the first antenna layer and the second circuit layer further comprises: and spraying ink on two surfaces of the double-sided copper-clad plate.
10. The method for manufacturing a high-frequency circuit board according to claim 8, wherein the drilling is performed by a laser drill.
CN202010040716.XA 2020-01-15 2020-01-15 High-frequency circuit board and manufacturing method thereof Pending CN111182713A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010040716.XA CN111182713A (en) 2020-01-15 2020-01-15 High-frequency circuit board and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010040716.XA CN111182713A (en) 2020-01-15 2020-01-15 High-frequency circuit board and manufacturing method thereof

Publications (1)

Publication Number Publication Date
CN111182713A true CN111182713A (en) 2020-05-19

Family

ID=70652703

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010040716.XA Pending CN111182713A (en) 2020-01-15 2020-01-15 High-frequency circuit board and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN111182713A (en)

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