JP2008078184A - Multilayer wiring board for mounting high-frequency chip, and high-frequency circuit module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer wiring board for mounting high-frequency chips which can be formed thin without degrading characteristics of circuit elements of a flip-chip mounted high-frequency chip, especially Q of an inductor, and to provide a high-frequency circuit module. <P>SOLUTION: The high-frequency circuit module 1 is formed by flip-chip mounting a high-frequency chip 2 to a multilayer wiring board 3 for mounting high-frequency chips. In the multilayer wiring board 3 for mounting high-frequency chips, an intermediate layer 5 is stacked under a surface layer 4, and a first ground surface 6a is formed in the ground layer 6 of the intermediate layer 5. The first ground surface 6a is provided with an opening 6b at a position opposite to an circuit element (especially inductor) 2a. In addition, a lower layer 8 is stacked under the intermediate layer 5, and a second ground surface 8a is formed under the opening 6b in the lower layer 8. The ground surface 8a is 200 μm or more away from the opening 6b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a high-frequency chip mounting multilayer wiring board and a high-frequency circuit module, and more particularly to a high-frequency chip mounting multilayer wiring board that can be suitably used for mounting a bare chip high-frequency chip by flip-chip mounting, and The present invention relates to a high frequency circuit module obtained by mounting a high frequency chip on the multilayer wiring board for mounting the high frequency chip.

  In wireless communication devices such as mobile phones and wireless LAN systems, due to recent improvements in integration technology, an oscillator (VCO) and an inductor in the LNA / MIX part, which were conventionally externally attached, are also used in the RF part of the RF part ( A high-frequency chip is a general term for semiconductor integrated circuits that use communication signals in a high-frequency band.) This inductor is patterned in a coil shape by a microstrip line on the surface of the high-frequency chip.

  Here, a general high-frequency chip is formed as a bare chip in order to reduce the thickness of a device on which the high-frequency chip is mounted and improve portability and space saving. As shown in FIGS. 4 and 5, bumps 2c for electrically connecting to the multilayer wiring board 103 are formed on the inductor forming surface 2b of the high-frequency chip 2 formed as a bare chip. The bumps 2c The high frequency chip 2 is flip-chip mounted on the multilayer wiring board 103 by facing the connection terminal 104 a of the multilayer wiring board 103.

  On the other hand, in the conventional multilayer wiring board 103 on which the high-frequency chip 2 is mounted, a connection terminal 104a for electrically connecting to a circuit component is formed on the surface of the first layer 104 as the uppermost layer. The metal ground surface 106a was formed on almost the entire surface of the second layer 106, which is the lower layer. Since the ground surface 106a exhibits a so-called shielding effect, the conventional multilayer wiring board 103 is caused by the wiring patterns 107a and 108a formed on the surfaces of the layers 107, 108, 110 and 111 below the third layer. This prevents unnecessary digital noise from being generated in the high-frequency chip 2.

  As described above, the conventional high-frequency circuit module 101 obtained by mounting the high-frequency chip 2 on the multilayer wiring board 103 can obtain a stable operation without being affected by noise (see Patent Document 1). reference).

JP 2006-121147 A

  However, the thickness of the wireless communication device incorporating the conventional high-frequency circuit module 101 is gradually getting smaller day by day, and accordingly, the thickness of the conventional multilayer wiring board 103 is about 0.1 mm (100 μm) per layer or It had to be formed to a thickness less than that. As a result, when the high-frequency chip 2 is flip-chip mounted on the conventional multilayer wiring board 103, the circuit element of the high-frequency chip 2, for example, the inductor 2a is close to the second-layer ground surface 106a of the multilayer wiring board 103, and the inductor 2a Since the electrostatic capacitance between the capacitor 2 and the ground surface 106a increases, there is a problem that the impedance of the inductor 2a decreases due to a resonance phenomenon between the electrostatic capacitance and the inductor 2a.

  When the impedance of the inductor 2a decreases, the inductance decreases, and the Q (quality-factor) of the inductor 2a decreases. For example, when the inductor 2a is used in an oscillator, if the inductance is reduced, the oscillation frequency may be shifted to the high frequency side. Further, the phase noise characteristic of the VCO is also deteriorated due to the decrease of the Q of the inductor 2a.

  Therefore, the present invention has been made in view of these points, and a multilayer for mounting a high-frequency chip that can be formed thin without reducing the characteristics of circuit elements of a high-frequency chip mounted on a flip chip, in particular, the Q of an inductor. The object is to provide a wiring board.

  In addition, the present invention provides a high-frequency circuit module that can prevent the characteristics of the circuit elements of the high-frequency chip, particularly the Q of the inductor, from being deteriorated even if the high-frequency chip is flip-chip mounted on the multilayer wiring board for high-frequency chip mounting. It is an object of the present invention to provide

  In order to achieve the above-described object, a multilayer wiring board for mounting a high-frequency chip according to the present invention has, as a first aspect, connected to a bump when a high-frequency chip having circuit elements and bumps formed on the surface is flip-chip mounted. A surface layer having connection terminals to be laminated, and an opening at a position opposite to the circuit element, the layer being laminated without being separated from the circuit element by a distance that does not cause deterioration of characteristics of the circuit element below the surface layer. An intermediate layer having a first ground plane, and a layer below the intermediate layer and separated from the circuit element by a distance that does not cause characteristic deterioration of the circuit element, and the opening. And a lower layer having a second ground plane having an area equal to or larger than that of the opening at the facing position. It is.

  According to the high-frequency chip mounting multilayer wiring board of the first aspect of the present invention, the first ground plane is formed in the intermediate layer, and the opening is formed in the first ground plane. Even if the thickness is made thin, it is possible to prevent the distance between the circuit element and the first ground plane from approaching and the capacitance from increasing, resulting in deterioration of characteristics. In addition, since the second ground plane is formed at a position separated from the circuit element by a distance that does not cause the characteristic deterioration of the circuit element, the wiring formed in the lower layer or a layer stacked below the lower layer It is possible to prevent unnecessary digital noise from occurring in the high-frequency chip due to the pattern.

  The multilayer wiring board for mounting a high-frequency chip according to a second aspect of the present invention is the multilayer wiring board for mounting a high-frequency chip according to the first aspect, wherein the intermediate layer is composed of one ground layer and at least one wiring layer. The ground layer is laminated closer to the surface layer than the wiring layer and has the first ground surface, and the wiring layer is sandwiched between the opening and the second ground surface. It is characterized in that it does not have a wiring pattern and a ground plane at the position.

  According to the multilayer wiring board for mounting a high-frequency chip of the second aspect of the present invention, the wiring pattern and the ground plane are not formed at the positions sandwiched between the opening and the second ground plane in the wiring layer. When the high frequency chip is mounted, it is possible to prevent the deterioration of the characteristics of the circuit elements, and it is possible to prevent the digital noise from adversely affecting the circuit elements of the high frequency chip.

  A multilayer wiring board for mounting a high-frequency chip according to a third aspect of the present invention is the multilayer wiring board for mounting a high-frequency chip according to the first or second aspect, wherein the circuit element is a coil-shaped element formed using a microstrip line. It is an inductor, and the opening is opened by a size equivalent to the size occupied by the inductor.

  According to the multilayer wiring board for mounting a high-frequency chip of the third aspect of the present invention, the inductor formed in a coil shape using the microstrip line is exposed on the surface, so that the capacitance with the ground plane is large. The impedance tends to decrease along with this, but by forming an opening in the first ground plane for the inductor and opening the opening to a minimum size, It is possible to minimize the occurrence of digital noise while preventing a decrease in impedance.

  The multilayer wiring board for mounting a high-frequency chip according to a fourth aspect of the present invention is the multilayer wiring board for mounting a high-frequency chip according to any one of the first to third aspects, wherein the opening is formed with the first ground plane. It is characterized by being formed as a through hole for electrically connecting the second ground plane.

  According to the multilayer wiring board for mounting a high-frequency chip of the fourth aspect of the present invention, a cylindrical metal film is formed between the first ground surface and the second ground surface, and the metal film is the first metal film. Since the gap formed between the ground plane and the second ground plane is separated, it is possible to prevent digital noise from entering between the first ground plane and the second ground plane. it can.

  The multilayer wiring board for mounting a high-frequency chip according to a fifth aspect of the present invention is the above-described multilayer wiring board for mounting a high-frequency chip according to any one of the first to fourth aspects. It is characterized by a distance of 200 μm or more.

  According to the multilayer wiring board for mounting a high-frequency chip according to the fifth aspect of the present invention, the circuit element of the high-frequency chip is deteriorated in characteristics by separating the circuit element of the high-frequency chip by a distance of 200 μm or more from the ground plane. For example, it is possible to prevent the Q of the inductor from being lowered.

  The high-frequency circuit module of the present invention has a multilayer wiring board for mounting a high-frequency chip according to any one of the first to fifth aspects, a circuit element, and a bump on the surface, and the bump is disposed on the surface. And a high-frequency chip that is flip-chip mounted while being electrically connected to a connection terminal of the multilayer wiring board for mounting the high-frequency chip.

  According to the high frequency circuit module of the present invention, the first ground plane is formed in the intermediate layer of the multilayer wiring board for high frequency chip mounting on which the high frequency chip is mounted, and the opening is formed in the first ground plane. Therefore, even if the surface layer and the intermediate layer are formed thin, it is possible to prevent the distance between the circuit element and the first ground plane from approaching and the capacitance from increasing, resulting in deterioration of characteristics. In addition, since the second ground plane is formed at a position separated from the circuit element by a distance that does not cause the characteristic deterioration of the circuit element, the wiring formed in the lower layer or a layer stacked below the lower layer It is possible to prevent unnecessary digital noise from occurring in the high-frequency chip due to the pattern.

  According to the multilayer wiring board for mounting a high-frequency chip and the high-frequency circuit module according to the present invention, the first ground plane close to the circuit element of the high-frequency chip has the opening, and the second ground is positioned opposite the opening. Therefore, the opposing distance between the circuit element (for example, the inductor) and the ground plane can be separated by a distance that does not cause deterioration of the characteristics of the circuit element while forming each layer thin. There is an effect that a multilayer wiring board for mounting a high-frequency chip can be thinly formed without deteriorating the characteristics of circuit elements, particularly the Q of the inductor.

  Hereinafter, a multilayer wiring board for mounting a high frequency chip and a high frequency circuit module according to the present invention will be described with reference to FIGS. Here, FIG. 1 is an exploded perspective view showing the high-frequency circuit module 1 of the present embodiment, and FIG. 2 is a cross-sectional view taken along arrow 2-2 of FIG.

  As shown in FIGS. 1 and 2, the high-frequency circuit module 1 of the present embodiment includes a high-frequency chip 2 and a multilayer wiring board 3 for mounting a high-frequency chip of the present embodiment.

  The high-frequency chip 2 is a semiconductor integrated circuit that uses a communication signal in a high-frequency band, and has circuit elements 2a necessary for wireless communication equipment such as a capacitor and an inductor. The high-frequency chip 2 is a bare chip, and the circuit elements 2a and bumps 2c described above are formed on the surface 2b facing the high-frequency chip mounting multilayer wiring board 3 when flip-chip mounting is performed. The circuit element 2a is formed using a microstrip line. For example, the inductor as one of the circuit elements 2a is formed in a coil shape using a microstrip line. The bump 2c is formed using a highly conductive metal such as Au or Al.

  As shown in FIGS. 1 and 2, the multilayer wiring board 3 for mounting a high frequency chip according to this embodiment includes a surface layer 4, an intermediate layer 5, and a lower layer 8. The surface layer 4, the intermediate layer 5, and the lower layer 8 are laminated in the order of the surface layer 4, the intermediate layer 5, and the lower layer 8 from above (in a direction close to the high frequency chip 2).

  The surface layer 4 has a plurality of connection terminals 4a formed using a highly conductive metal such as Cu, Al, Ag on the surface of the insulating substrate 4g, and is arranged at a position closest to the high-frequency chip 2. It is installed. Since the connection terminals 4a come into contact with the bumps 2c of the high frequency chip 2 when the high frequency chip 2 is flip-chip mounted, the connection terminals 4a are arranged corresponding to the positions where the bumps 2c are formed. The surface layer 4 and the other layers 6, 7, 8, and 9 are formed to a thickness of about 100 μm in order to reduce the thickness of the multilayer wiring board 3 for mounting a high frequency chip.

  The intermediate layer 5 is laminated below the surface layer 4. In the present embodiment, the intermediate layer 5 is formed by laminating one ground layer 6 and one wiring layer 7.

  The ground layer 6 is laminated closer to the surface layer 4 than the wiring layer 7, and is formed on the surface of the insulating substrate 6 g using a highly conductive metal such as Cu, Al, or Ag. 1 ground surface 6a. As described above, since the thickness of the surface layer 4 is about 100 μm, the ground layer 6 is laminated at a position at least about 100 μm away from the high-frequency chip 2.

  The first ground surface 6a of the ground layer 6 has an opening 6b at a position facing the circuit element 2a. Of all the circuit elements 2a included in the high-frequency chip 2, the inductor exhibits the greatest characteristic deterioration when close to the ground plane. Therefore, the opening 6b of the present embodiment has an inductor as shown in FIG. The opening is the same size as the occupied size. When the placement position of the inductor cannot be specified or when the characteristic deterioration of the other circuit element 2a is taken into consideration, the size of the opening 6b is preferably opened by a size equivalent to the size occupied by the high-frequency chip 2.

  The wiring layer 7 has a wiring pattern 7a and a ground plane 7b formed on the surface of the insulating substrate 7g using a highly conductive metal such as Cu, Al, or Ag (the wirings in FIGS. 1 and 2). The pattern 7a and the ground plane 7b are merely examples.) However, the wiring pattern 7a and the ground surface 7b are not formed on the surface of the wiring layer 7 and below the opening 6b. In other words, the wiring pattern 7 a and the ground surface 7 b that face the high-frequency chip 2 through the opening 6 b do not exist in the wiring layer 7.

  The lower layer 8 is laminated below the intermediate layer 5. Here, the intermediate layer 5 of the present embodiment is composed of the ground layer 6 and the wiring layer 7. Each layer has a thickness of about 100 μm and a total thickness of about 200 μm, and the surface layer 4 has a thickness of about 100 μm. Therefore, the lower layer 8 is laminated at a distance of at least about 300 μm from the circuit element 2 a of the high frequency chip 2.

  Further, the lower layer 8 has a second ground surface 8a on the surface of the insulating substrate 8g having a surface area equal to or larger than that of the opening 6b at a position facing the opening 6b. Yes. The second ground surface 8a is formed using a highly conductive metal such as Cu, Al, or Ag, and is formed on a part of the surface of the lower layer 8 as shown in FIG. However, the second ground surface 8a may be formed on the entire surface of the lower layer 8, although not shown.

  Further, as shown in FIG. 2, the second ground surface 8a is electrically connected to the first ground surface 6a by using a through hole 9 drilled downward from the opening 6b of the first ground surface 6a. It is preferable that it is connected to. By using the opening 6 b as the through hole 9, the first ground surface 6 a and the second ground surface 8 a have a cylindrical shape that covers the side surface of the through hole 9 formed using the opening 6 b of the ground layer 6. They are continuously connected by the metal film 9a.

  Note that a ground layer 11 having a wiring layer 10 and a ground surface 11 a may be laminated below the lower layer 8.

  Next, the operation of the high-frequency chip mounting multilayer wiring board 3 and the high-frequency circuit module 1 according to this embodiment will be described with reference to FIGS. 1 to 3. Here, FIG. 3 is a graph showing characteristic deterioration of the inductor.

  The high-frequency chip mounting multilayer wiring board 3 of the present embodiment includes a surface layer 4, an intermediate layer 5, and a lower layer 8, as shown in FIGS. When the surface layer 4 is referred to as a first layer, the ground layer 6 of the intermediate layer 5 is a second layer, and a first ground surface 6a is formed on the ground layer 6 as the second layer. Since the thickness of each layer is made uniform, the surface layer 4, the intermediate layer 5, and the lower layer 8 are also uniformly thinned when the multilayer wiring board 3 for mounting a high frequency chip is thinned. For this reason, when each layer is thinned, the high frequency chip 2 is brought close to the first ground plane 6a so that the characteristic deterioration of the circuit element 2a of the high frequency chip 2, particularly the inductor, becomes remarkable.

  Therefore, an opening 6b is formed in the first ground surface 6a of the ground layer 6 of the present embodiment at a position facing the circuit element 2a of the high-frequency chip 2, particularly the inductor. Therefore, even if each layer is formed thin and the distance between the position where the high-frequency chip 2 is disposed and the first ground plane 6a approaches, the circuit element 2a of the high-frequency chip 2 is connected to the first ground plane 6a. Can be kept away from As a result, the multilayer wiring board 3 for mounting a high-frequency chip according to the present embodiment is such that when the high-frequency chip 2 is flip-chip mounted, the distance between the circuit element 2a, in particular, the inductor and the first ground plane 6a is reduced. Therefore, it is possible to prevent unnecessary capacitance generated in the inductor from being increased and the characteristics of the inductor from being deteriorated.

  In the present embodiment, when the high-frequency chip 2 is flip-chip mounted, the lower layer 8 is separated by a distance (this distance will be described later in detail) from which the circuit element 2a does not deteriorate in characteristics. The second ground surface 8a having the same area as the opening 6b or larger than the opening 6b at a position facing the opening 6b of the first ground surface 6a in the lower layer 8 thereof. Is formed. Therefore, the shielding effect of the first ground surface 6a and the second ground surface 8a as a whole is almost the same as the shielding effect of the first ground surface 6a having no opening 6b, and the shielding effect is obtained by forming the opening 6b. Will not deteriorate. Therefore, when the high frequency chip 2 is flip-chip mounted on the high frequency chip mounting multilayer wiring board 3 of the present embodiment, the cause is the wiring pattern 8c formed in the lower layer 8 or a layer laminated below the lower layer 8. Thus, unnecessary digital noise can be prevented from occurring in the high-frequency chip 2.

  However, if the wiring pattern 7a or the ground surface 7b of the wiring layer 7 is formed at a position between the opening 6b and the second ground surface 8a, the wiring pattern 7a or the ground surface 7b and the high-frequency chip 2 are formed. And the circuit element 2a are coupled to each other, leading to deterioration of the characteristics of the circuit element 2a. Further, even if the wiring layer 7 is laminated by a distance that does not cause the characteristic deterioration of the circuit element 2a, if the wiring pattern 7a is formed at a position facing the high-frequency chip 2 through the opening 6b, The circuit element 2a of the high frequency chip 2 is adversely affected by digital noise. Therefore, in the wiring layer 7 of the present embodiment, the wiring pattern 7a and the ground surface 7b are formed so as not to be disposed between the opening 6b and the second ground surface 8a. Thereby, the characteristic deterioration of the circuit element 2a can be prevented, and the influence of digital noise on the circuit element 2a of the high-frequency chip 2 can be prevented.

  Here, how far the lower layer 8 having the second ground surface 8a is stacked from the circuit element 2a of the high-frequency chip 2 depends on whether or not the circuit element 2a is deteriorated in characteristics by the second ground surface 8a. That is, the distance is determined such that the characteristic of the circuit element 2a does not deteriorate. Among the circuit elements 2a of the high-frequency chip 2, it is an inductor that is most likely to be deteriorated in characteristics by being brought close to the ground plane (second ground plane 8a in the present embodiment). As shown in FIG. 3, when the distance from the ground plane is about 0 to 200 μm, the inductor has a large capacitance between the inductor and the ground, and its oscillation frequency changes greatly. It is known to be. However, it is also known that the transmission frequency does not change much if the distance from the ground plane is 200 μm or more. Therefore, in this embodiment, by setting the distance at which the characteristic deterioration of the circuit element 2a does not occur to a distance of 200 μm or more, the circuit element 2a of the high frequency chip 2 is deteriorated, for example, the inductor Q is reduced. Can be prevented.

  The distance at which the characteristic deterioration of the circuit element 2a described above does not occur is adjusted by the thickness of the surface layer 4 laminated above the lower layer 8, and the ground layer 6 and the wiring layer 7 of the intermediate layer 5. In the present embodiment, each layer has a thickness of about 100 μm and is separated from the circuit element 2 a by at least about 300 μm, so that the above-mentioned distance condition of 200 μm or more is satisfied. If the total thickness of the surface layer 4 and the intermediate layer 5 becomes 200 μm or less because each layer is formed thin, another wiring layer is interposed between the ground layer 6 and the lower layer 8 of the intermediate layer 5. 7 and a dummy layer are laminated and adjusted so as to satisfy the condition of a distance of 200 μm or more.

  However, as shown in FIG. 1, when there is a wiring layer 7 between the first ground surface 6a and the second ground surface 8a, the wiring pattern 7a of the wiring layer 7 is connected to the high-frequency chip 2 through the opening 6b. Even if it is not formed at the opposite position, digital noise generated from the wiring pattern 7a of the wiring layer 7 may enter from the opening 6b. Therefore, the opening 6b of the present embodiment is opened by a size equivalent to the size occupied by the inductor of the high-frequency chip 2. Since the inductor is formed in a coil shape on the surface 2b of the high-frequency chip 2 using a microstrip line, when the capacitance between the inductor and the ground surface increases, a resonance phenomenon occurs and impedance tends to decrease. Therefore, by forming the opening 6b in the first ground plane 6a in accordance with the size of the inductor that is particularly susceptible to characteristic deterioration, it is possible to prevent a decrease in impedance and to allow digital noise to enter. Can be minimized.

  Of course, as shown in FIG. 2, the opening 6b formed in the first ground surface 6a is most preferably formed as a through hole 9 connected to the second ground surface 8a. That is, in the present embodiment, by using the opening 6b as the through hole 9, a cylindrical metal film 9a is formed between the first ground surface 6a and the second ground surface 8a, and the cylindrical shape The metal film 9a can separate a gap formed between the first ground surface 6a and the second ground surface 8a. As a result, the first ground surface 6a and the second ground surface 8a are continuously formed through the through holes 9 formed in the opening 6b, so that the first ground surface 6a and the second ground surface are formed. It is possible to prevent digital noise from entering between 8a and 8a.

  The high-frequency circuit module 1 according to the present embodiment is obtained by flip-chip mounting the high-frequency chip 2 on the multilayer wiring board 3 for mounting a high-frequency chip according to the present embodiment described above. When the high-frequency chip 2 is flip-chip mounted, the surface 2b of the high-frequency chip 2 on which the circuit element 2a is formed faces the surface layer 4 of the multilayer wiring board 3 for mounting the high-frequency chip, and the circuit element 2a is likely to be close to the surface layer 4. Become. Therefore, in the high-frequency circuit module 1 of the present embodiment, as described above, the first ground surface 6a is formed on the intermediate layer 5 of the multilayer wiring board 3 for mounting a high-frequency chip, and the first ground surface 6a is formed on the first ground surface 6a. Since the opening 6b is formed, it is possible to prevent the circuit element 2a of the high-frequency chip 2 that is flip-chip mounted from deteriorating characteristics.

  In the high frequency circuit module 1 of the present embodiment, since the second ground plane 8a is formed at a position separated from the circuit element 2a by a distance that does not cause deterioration of the characteristics of the circuit element 2a, digital noise is generated by the high frequency chip. 2 can be prevented.

  That is, according to the multilayer wiring board 3 for mounting a high-frequency chip and the high-frequency circuit module 1 of the present embodiment, the opening 6b is provided in the first ground plane 6a adjacent to the circuit element 2a of the high-frequency chip 2, and the opening Since the second ground plane 8a is provided at the position opposite to the portion 6b, the characteristic distance of the circuit element 2a is deteriorated with respect to the facing distance between the circuit element 2a (for example, an inductor) and the ground plane while each layer is formed thin. Therefore, the multilayer wiring board 3 for mounting a high frequency chip can be thinly formed without deteriorating the characteristics of the circuit element 2a of the high frequency chip 2, particularly the inductor.

  In addition, this invention is not limited to embodiment mentioned above etc., A various change is possible as needed.

  For example, two or more wiring layers 7 of the intermediate layer 5 may be laminated, or the intermediate layer 5 may be formed only by the ground layer 6 without laminating one wiring layer 7.

  In the present embodiment, the opening 6b is formed to be the through hole 9, but in other embodiments, the opening 6b is formed by providing a hole only in the first ground surface 6a. A through hole (not shown) for connecting the first ground surface 6a and the second ground surface 8a may be formed in another portion.

Exploded perspective view showing the high-frequency circuit module of the present embodiment 2-2 sectional view of FIG. Graph showing deterioration of inductor characteristics An exploded perspective view showing a conventional high-frequency circuit module 4-5 arrow sectional view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High frequency circuit module 2 High frequency chip 3 Multilayer wiring board for high frequency chip mounting 4 Surface layer 5 Intermediate layer 6 Ground layer 6a First ground surface 6b Opening 7 Wiring layer 8 Lower layer 8a Second ground surface 9 Through hole 9a Metal film

Claims (6)

A surface layer having connection terminals to be connected to the bumps when flip-chip mounting a high-frequency chip having circuit elements and bumps formed on the surface;
A first ground plane having an opening at a position facing the circuit element is provided below the surface layer without being separated from the circuit element by a distance that does not cause deterioration of characteristics of the circuit element. Intermediate layer,
Below the intermediate layer, the circuit elements are stacked apart from the circuit element by a distance that does not cause deterioration in characteristics of the circuit element, and are equal to or larger than the opening at a position facing the opening. A multilayer wiring board for mounting a high-frequency chip, comprising: a lower layer having a second ground plane having an area. The intermediate layer is composed of one ground layer and at least one wiring layer,
The ground layer is laminated closer to the surface layer than the wiring layer, and has the first ground surface.
2. The multilayer wiring board for mounting a high frequency chip according to claim 1, wherein the wiring layer does not have a wiring pattern and a ground surface at a position sandwiched between the opening and the second ground surface. The circuit element is a coiled inductor formed using a microstrip line,
The multilayer wiring board for mounting a high-frequency chip according to claim 1 or 2, wherein the opening is opened by a size equivalent to a size occupied by the inductor. The said opening part is formed as a through-hole which electrically connects a said 1st ground surface and a said 2nd ground surface, The any one of Claims 1-3 characterized by the above-mentioned. Multi-layer wiring board for mounting high frequency chips. 5. The multilayer wiring board for mounting a high-frequency chip according to claim 1, wherein the distance at which the characteristic deterioration of the circuit element does not occur is a distance of 200 μm or more. A multilayer wiring board for mounting a high-frequency chip according to any one of claims 1 to 5,
A circuit element and a bump are provided on the surface, and a high-frequency chip that is flip-chip mounted while electrically connecting the bump to a connection terminal of the multilayer wiring board for mounting the high-frequency chip. High frequency circuit module.

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