JP2002111208A - Multilayered dielectric substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayered dielectric substrate having such a structure that through holes used for connecting signal lines of multiple layers to each other can be formed between arbitrary layers with a high degree of freedom. SOLUTION: The lower ends of the through holes 2 are positioned to the positions of cover pads 6 on a dielectric substrate 1c constituting the multilayered dielectric substrate, and the upper ends of the holes 2 are positioned to the positions corresponding to the right ends of strip lines 4 on another dielectric substrate 1b also constituting the multilayered dielectric substrate. On the substrate 1b, both ends of the strip lines 4 have notches 16 and the right ends of the lines 4 are positioned to the positions corresponding to the upper ends of the through holes 2 on the substrate 1c. In addition, the lower ends of the through holes 2 are positioned to the left ends of the strip lines 4 arranged at prescribed positions, and the upper ends of the holes 2 are positioned to the positions corresponding to the cover pads 6 of a dielectric substrate 1a. Therefore, when the dielectric substrates 1b and 1c are laminated upon another, the through holes 2 made through the substrates 1b and 1c can be connected to each other by aligning the connecting spots of the through holes 2 with each other and melting metallic bumps 9 by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer dielectric substrate, and more particularly, to a multilayer dielectric substrate having a through-hole used for connection between signal lines in a multilayer structure of a high-frequency substrate such as a Teflon substrate. Related to a body substrate.

[0002]

2. Description of the Related Art FIG. 4 shows a configuration of a multilayer substrate using a conventional Teflon substrate. Here, 2 is a through-hole formed in a straight line through the multilayers, 3 is a ground plane, 4 is a strip line that forms a metal pattern, 5 is a microstrip line that forms a metal pattern, 6 is a cover pad, and 7 is a cover pad. Reference numerals 14a to 14d denote Teflon substrates. Conventionally, when multi-layering is performed using Teflon substrates 14a to 14d having excellent high-frequency characteristics, the layers are adhered to each other using a thermocompression bonding sheet, and through holes 2 are used for interlayer connection of high-frequency signals. ing.

[0003]

However, in the conventional multi-layer structure using a Teflon substrate, the through hole 2 can be used only for the through-hole type, and can be used only for the connection between the fixed layers. There is a large limitation in forming a multi-layer structure of three or more substrates. In addition, a method of connecting through layers or electromagnetically is generally used for connection between layers, and free connection has been difficult.

That is, in the conventional Teflon substrate configuration, the through-hole 2 is realized by using a through-hole, and the bonding between the dielectric substrates is realized by using an insulating adhesive. Therefore, it is difficult to make an electrical connection between the layers, and it is basically impossible to freely form a through hole between all the layers.

There is a ceramic substrate as a substrate material suitable for a multi-layer substrate structure. However, since it has a high dielectric constant characteristic for use in an antenna, the frequency band can be narrowed and a substrate size of several tens cm square or more. There is a problem that it is difficult to realize this.

The present invention has been made in view of such a point. In particular, in the case of multi-layering a substrate for high frequency use such as a Teflon substrate, a through hole used for connecting signal lines between layers is optional. It is an object of the present invention to provide a multilayer dielectric substrate having a structure that can be manufactured with a high degree of freedom between layers.

[0007]

In the multilayer dielectric substrate of the present invention, a notch is provided in an adhesive material layer around a connecting portion of a through hole, and a metal bump is provided at a connecting portion of the through hole in each dielectric substrate. This prevents insulation at the connection points and enables a multilayer structure.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In order to achieve the above object, a multilayer dielectric substrate according to the present invention is a multilayer dielectric substrate in which a plurality of dielectric substrates 1 are laminated to form a multilayer structure. The substrates 1 are bonded together using an adhesive layer 15, and the adhesive layer 15 is provided with a notch 16 near the connection point of the through hole 2, and the connection between the through holes 2 in the multilayer dielectric substrate, or The connection between the through-hole 2 and the metal pattern is made by using a metal bump 9 provided at the connecting portion of the through-hole 2 so that the connection between the layers using the through-hole 2 can be performed. Have.

[0009] The material of the multilayer dielectric substrate is characterized in that it is a resin such as polyimide or liquid crystal polymer or Teflon.

Further, the present invention is characterized in that a substrate made of ceramic is used as at least one or more dielectric substrates 1 among the multilayer dielectric substrates.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1A is a view showing the structure of a multilayer dielectric substrate according to a first embodiment of the present invention.
FIG. 3 is a cross-sectional view of a multilayer substrate stacked by layers.
Here, 1 is a dielectric substrate, 2 is a through hole, 3 is a ground plane, 4 is a strip line that forms a metal pattern, 5 is a microstrip line that forms a metal pattern, 6 is a cover pad, 7 is a feed element, 8 Is a parasitic element.
The dielectric substrate 1 in this embodiment is a Teflon substrate.
Note that this multi-layer substrate configuration is a configuration for realizing a through-hole 2 having a high degree of freedom, which can be easily realized by a resin-based substrate such as polyimide, also by a Teflon substrate or the like.

FIG. 2B shows details of an example of connection between layers by the through hole 2. Here, 1a is a dielectric substrate having an upper ground plate 3, 1b is a dielectric substrate having an adhesive layer 15, 1c is a dielectric substrate having a lower ground plate 3, 4 is a strip line, and 5 is a microstrip line. , 6 are cover pads, 9 is a metal bump provided at a connection point of the through hole 2, and 16 is a cutout of the adhesive layer 15 provided near the connection point of the through hole 2.

First, the through hole 2 in the dielectric substrate 1c will be described. As shown in the figure, a metal bump 9 is provided at a connection position of the through hole 2. The metal bump 9 has a cylindrical shape, but melts when heated for connection, and becomes substantially flat. Through hole 2
Is disposed at the position of the cover pad 6 of the base plate 3, and the upper end thereof is disposed at a position corresponding to the right end of the strip line 4 of the dielectric substrate 1b.

Next, the strip line 4 and the through hole 2 in the dielectric substrate 1b will be described. Notches 16 of an adhesive layer 15 are provided at both ends of the strip line 4. As described above, the right end is located at a position corresponding to the upper end of the through hole 2 of the dielectric substrate 1c, and the left end is located at a predetermined position. Dielectric substrate 1
b, the lower end of the through hole 2 is disposed on the left end of the strip line 4, and the upper end of the through hole 2 is
It is arranged at a position corresponding to the cover pad 6 of FIG.

Therefore, when the dielectric substrates 1b and 1c are laminated by bonding with the adhesive layer 15, the positions of the connection points of the through holes 2 are aligned, and the metal bumps 9 are heated and melted to thereby form the mutual connection. The through holes 2 of the dielectric substrates 1b and 1c can be connected to each other, and one end of the through hole 2 can be connected to the metal layer of one layer. Connection is possible in the same way. However, it is necessary to provide a cutout 16 in the adhesive layer 15 near the connection point of the through hole 2 to prevent insulation.

FIG. 2 is a view showing the structure of a multilayer dielectric substrate according to a second embodiment of the present invention, and is a cross-sectional view of a multilayer substrate in which six Teflon substrates and three polyimide resin substrates are stacked. Things. Here, 1 is a dielectric substrate made of a Teflon substrate, 2 is a through hole, 3 is a ground plate, 4
Is a strip line, 5 is a microstrip line, 6 is a cover pad, 7 is a feed element, 8 is a passive element, 10 is a polyimide substrate laminated below the dielectric substrate 1,
Reference numeral 11 denotes an MMIC chip provided on the polyimide substrate 10, and reference numeral 12 denotes an Au wire of the MMIC chip 11.

Although this multilayer substrate has excellent high-frequency characteristics using only a multilayer Teflon substrate, it is difficult to sufficiently integrate a complicated control circuit and the like. Therefore, a multilayer substrate made of a polyimide resin substrate 10 is added as an auxiliary to the Teflon substrate. This is an embodiment of the present invention. This board uses a Teflon board to create a circuit that requires excellent high-frequency characteristics over the microwave band, and realizes a circuit pattern and the like that is complex and does not require high-frequency characteristics with integrated circuits, high-frequency circuits, and control circuits. Only when the polyimide substrate 10 is used, an efficient multi-layer substrate configuration is realized. A similar effect can be obtained by using a substrate using a liquid crystal polymer instead of the polyimide substrate 10 described above.

FIG. 3 is a view showing the structure of a multilayer dielectric substrate according to a third embodiment of the present invention. Two layers of a Teflon substrate, four layers of a ceramic substrate below the substrate, and further a polyimide resin substrate are provided. FIG. 3 is a cross-sectional view of a multi-layer substrate configuration having a total number of 9 layers stacked three layers. Here, 1 is a dielectric substrate made of a Teflon substrate, 2 is a through hole, 3 is a ground plane, 4 is a strip line, 5 is a microstrip line, 6 is a cover pad, 7 is a feed element, 8 is a passive element, 10 Is a polyimide substrate, 11 is an MMIC chip, 1
Reference numeral 2 denotes an Au wire, and reference numeral 13 denotes a ceramic substrate.

The present multilayer substrate realizes a microstrip antenna with a parasitic element in a multilayer Teflon substrate. The parasitic element 8 and the second layer are formed on the first layer of the dielectric substrate 1.
The feed element 7 is formed in a layer. In the ceramic substrate layer 13, an array power supply circuit connected to the power supply element 7 is formed, and the ceramic substrate 1
3 shows an example in which an active device in the form of an MMIC chip is mounted on the lower surface of No. 3. Here, in particular, the ceramic substrate 13
Not only allows the power supply circuit to be reduced in size due to the high dielectric constant, but also because the active device is directly connected to the surface of the ceramic substrate 13 so that the high thermal conductivity of the substrate 13 reduces the power consumption. The Teflon substrate has an advantage that heat radiation, which is unthinkable, is possible.

[0020]

As described above, according to the multilayer dielectric substrate of the first aspect of the present invention, at least two dielectric substrates are formed by laminating a plurality of dielectric substrates 1 to form a multilayer structure.
At least one dielectric substrate 1 is bonded using an adhesive layer 15, and a cutout 16 is provided in the adhesive layer 15 near a connection point of the through-hole 2, so that the through-hole 2 in the multilayer dielectric substrate is The connection between them or the connection between the through hole 2 and the metal pattern is made by using a metal bump 9 provided at the connection point of the through hole 2, and the connection between the layers using the through hole 2 can be made. I did it. As a result, it is possible to freely connect between the layers, and to connect a complicated line without trouble in arrangement.

A feature of the multilayer dielectric substrate according to the present invention is that the substrate material constituting the multilayer dielectric substrate is:
It is to form a multilayered dielectric substrate 1 using a resin such as polyimide or liquid crystal polymer or Teflon.
Therefore, multilayering with a thin substrate is possible. Thereby, a finer line circuit can be arranged. Therefore, a more complicated circuit can be designed.

Further, the feature of the multilayer dielectric substrate according to the present invention is that at least one of the multilayer dielectric substrates is provided.
It is to use a substrate made of ceramic as a raw material for one or more dielectric substrates 1. Therefore, high thermal conductivity, which cannot be realized with a Teflon substrate, can be used. This makes it possible to easily achieve heat radiation of a small power amplifier. Therefore, simpler thermal design becomes possible.

[Brief description of the drawings]

FIG. 1A is a diagram showing a structure of a multilayer dielectric substrate according to a first embodiment of the present invention, and FIG. 1B is a diagram showing details of interlayer connection by through holes.

FIG. 2 is a diagram showing a structure of a multilayer dielectric substrate according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a structure of a multilayer dielectric substrate according to a third embodiment of the present invention.

FIG. 4 is a diagram showing an antenna configuration for realizing conventional spatial power combining.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 dielectric substrate 2 through hole 3 ground plane 4 strip line 5 microstrip line 6 cover pad 7 feed element 8 parasitic element 9 metal bump 10 polyimide substrate 11 MMIC chip 12 Au wire 13 ceramic substrate 14 a to d Teflon substrate 15 adhesive layer 16 Notch

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01Q 21/06 H01Q 21/06 H05K 1/11 H05K 1/11 H (72) Inventor Toshikazu Hori Chiyoda, Tokyo 2-3-1, Otemachi-ku, Tokyo F-term (reference) in Nippon Telegraph and Telephone Corporation 5E317 AA01 AA24 BB01 BB11 CC53 GG16 5E346 AA13 AA43 CC10 CC14 CC16 CC21 EE12 FF45 HH17 HH24 5J021 AA09 AB06 HA05 HA10 JA07 5J045 AB05 DA06 AB06 DA06 FA02 HA03 MA07 NA01 5J046 AA07 AB13 QA02

Claims (3)

[Claims] 1. A multi-layer dielectric substrate in which a plurality of dielectric substrates (1) are laminated to form a multilayer, wherein at least two or more dielectric substrates (1) are bonded to an adhesive layer (1).
The adhesive layer (15) is provided with a notch (16) in the vicinity of the connection point of the through hole (2), and the adhesive layer (15) is provided between the through holes (2) in the multilayer dielectric substrate. The connection or the connection between the through hole (2) and the metal pattern is made by using a metal bump (9) provided at the connecting portion of the through hole (2), and between the layers using the through hole (2). A multilayer dielectric substrate, characterized in that it can be connected. 2. The multilayer dielectric substrate according to claim 1, wherein a material of said multilayer dielectric substrate is resin such as polyimide or liquid crystal polymer or Teflon (registered trademark). 3. At least one of said multilayer dielectric substrates
The multilayer dielectric substrate according to claim 1, wherein a substrate made of ceramic is used as the one or more dielectric substrates.