JP6734750B2 - High frequency package - Google Patents

Description

The present invention relates to a high frequency package capable of transmitting a high frequency signal, and more particularly, to a high frequency package configured to have an electronic component mounted thereon and capable of transmitting a high frequency signal via a transmission line.

Conventionally, a high-frequency package has been used in which electronic components such as semiconductor chips are placed on a laminated substrate including a plurality of dielectric layers, and a transmission line of a high-frequency signal transmitted between the electronic components and an external substrate is configured. There is. The design of the wiring structure is important to realize a high-frequency package with good high-frequency signal transmission characteristics. That is, it is required to design in consideration of impedance matching in order to suppress the influence of capacitive coupling between signal lines and the inductance component as much as possible and to reduce the reflection loss in the input/output section. A general transmission line in this type of high-frequency package is, for example, a signal wiring formed from an electronic component terminal to an upper dielectric layer, a plurality of via conductors extending in the stacking direction, and a lower dielectric layer. There is known a wiring structure in which an external terminal is electrically connected via each of the signal wirings formed in (1) to (4). Among them, the plurality of via conductors shown in Patent Documents 1, 2, and 4 have a structure in which individual via conductors penetrating each dielectric layer extend linearly along the stacking direction, while in Patent Document 3, The plurality of via conductors shown have a structure in which the whole extends obliquely when viewed in cross section.

Japanese Patent No. 4413234 JP, 2007-53411, A JP-A-6-21253 JP, 2014-154593, A

In the above-mentioned conventional wiring structure, by shortening the length of the signal wiring in the ground conductor removal region other than the coplanar line structure in the upper layer and the lower layer, the influence of the inductance component in this portion is reduced. In addition to this, the wiring structure of Patent Document 3 has an effect of suppressing the influence of multiple reflection because there are no discontinuous connection points in the plurality of via conductors. However, in the wiring structure of Patent Document 3, since the entire plurality of via conductors are obliquely extended, the distance from the surrounding ground via conductor cannot be kept constant, and impedance matching is ensured at this portion. Becomes difficult to do. Therefore, even if the above-mentioned conventional wiring structure is adopted, it is difficult to realize good high frequency characteristics by achieving both suppression of the influence of multiple reflection and good impedance matching.

The present invention has been made to solve the above problems, and provides a high-frequency package that achieves both good suppression of the effects of multiple reflections and good impedance matching, and good transmission characteristics of high-frequency signals. Is.

In order to solve the above problems, a high-frequency package of the present invention is a high-frequency package capable of mounting an electronic component on a laminated substrate including a plurality of laminated dielectric layers, and has a terminal of the electronic component in plan view. A first signal line extending in a first direction from a terminal pad connected to the first pad to a first connection point formed on the first dielectric layer of the plurality of dielectric layers; A second signal line extending in the first direction from a second connection point formed on a second dielectric layer of the plurality of dielectric layers to a pad for external connection; and the plurality of dielectric layers A plurality of via conductors that penetrate through the stack in the stacking direction and electrically connect between the first connection point and the second connection point, and the plurality of dielectric layers each include the plurality of via conductors in plan view. And a ground conductor formed so as to surround a region in which the via conductor is arranged. The plurality of via conductors extend from an upper end portion formed in a dielectric layer below the first dielectric layer to a lower end portion formed in a dielectric layer above the second dielectric layer. A linear via portion extending linearly along the stacking direction, a first diagonal via portion extending diagonally from the first connection point to the upper end portion of the linear via portion, and the second A second diagonal via portion extending diagonally from a connection point to the lower end portion of the linear via portion , wherein the first signal wiring is formed on one surface of the laminated substrate, and the laminated substrate. A position where the second signal wiring is formed on the other surface of the first connection point, and the first connection point, the linear via portion, and the second connection point are sequentially displaced along the first direction in a plan view. It is characterized by being placed in.

According to the high frequency package of the present invention, a high frequency signal is transmitted via the transmission line including the first signal wiring, the plurality of via conductors, and the second signal wiring, and the plurality of via conductors are Connecting the first diagonal via portion, the linear via portion, and the second diagonal via portion from the first connection point on the first signal wiring side to the second connection point on the second signal wiring side. It has a structure. In this case, the positions of the first connection point, the linear via portion, and the second connection point are sequentially shifted along the first direction in a plan view, whereby the first and second signal wirings are arranged. The inductance component can be reduced by shortening the length of the signal wiring in the ground conductor removal region. With the wiring structure of the present invention, it is possible to suppress multiple reflection due to discontinuous connection points between via conductors that are adjacent to each other in the stacking direction, and in comparison with the case where the entire plurality of via conductors are arranged diagonally. Since the lengths of the first and second diagonal via portions can be shortened and the impedances can be matched, it is easy to ensure good impedance matching.

In the present invention, each of the first and second diagonal via portions can be a via portion that penetrates two or three dielectric layers of the plurality of dielectric layers. In this case, the portion where each of the first and second diagonal via portions is formed preferably has a thickness in the range of 15% to 30% with respect to the total thickness of the plurality of dielectric layers. .. If the thickness of the portion where each of the first and second diagonal via portions is formed is too thin, the impedance cannot be matched due to the influence of the inductance component. Further, if the thickness of the formation portion of the first and second diagonal via portions is too large, the impedance of the diagonal via portions becomes low, which impedes impedance matching.

In the present invention, the via diameters of the first and second oblique via portions can be set to be the same or slightly larger than the via diameter of the linear via portion in plan view. Here, "slightly large" means that the via diameters of the first and second oblique via portions are several percent (0.1 to 15%) larger than the via diameter of the linear via portion. In this case, it is desirable to set the via diameter of each of the straight via portion and each of the first and second diagonal vias so as to have a desired characteristic impedance. When the characteristic impedance of the transmission line of the high frequency package is designed to be, for example, 50Ω, it can be dealt with by appropriately adjusting the via diameters of the first and second diagonal vias with respect to the straight via portion.

According to the present invention, as a high-frequency signal transmission line in a high-frequency package, a plurality of via conductors connecting upper and lower signal wirings are connected to a first diagonal via portion, a straight via portion, and a second diagonal via portion. In addition, by defining the predetermined arrangement order along the first direction in plan view, the length of the signal wiring in the ground conductor removal region of the upper and lower signal wirings is shortened to reduce the inductance component, and It is possible to suppress the multiple reflection from the discontinuous connection portion of the via conductor, and it is possible to easily secure the impedance matching by the linear via portion at the center in the stacking direction. Therefore, by combining these, it is possible to improve the transmission characteristics of the high frequency signal in the high frequency package.

It is sectional drawing of the partial area|region of the high frequency package 1 of this embodiment. FIG. 2 is a plan view of a region of the high frequency package 1 shown in FIG. 1 viewed from above a dielectric layer L(1). This is a modification example of the wiring structure of FIG. 1 in which each of the formation portions of the diagonal via portions 21 and 22 has a thickness in the range of 15 to 30% of the whole. It is a typical sectional view regarding a comparative example having a conventional wiring structure. It is a figure which shows the verification result of the S parameter of a comparative example (FIG. 4). It is a figure which shows the verification result of the S parameter of this embodiment (FIG. 1). It is a figure which shows the verification result of the impedance of a comparative example (FIG. 4). It is a figure which shows the verification result of the impedance of this embodiment (FIG. 1).

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below is an example of a mode to which the present invention is applied, and the present invention is not limited by the contents of the present embodiment.

The outline of the structure of the high-frequency package of the present embodiment will be described with reference to FIGS. 1 and 2. 1 shows a cross-sectional view of a partial region of the high frequency package 1 of the present embodiment, and FIG. 2 shows a plan view of the high frequency package 1 shown in FIG. 1 as seen from above the dielectric layer L(1). ing. In the high frequency package 1 of the present embodiment, an electronic component (not shown) such as a semiconductor chip is placed in a region (right side of FIG. 1) not shown in FIGS. 1 and 2, and a plurality of terminals of the electronic component are arranged. The wiring structure of the present invention is formed for electrical connection with an external circuit. In FIGS. 1 and 2, one transmission line from one terminal pad (not shown) connected to the terminal of the electronic component to one external connection pad (not shown) on the bottom surface of the high-frequency package 1 is provided. An applied wiring structure is illustrated.

The laminated substrate of the high frequency package 1 shown in FIG. 1 has a structure in which a plurality of dielectric layers L are laminated in total. Among these, eleven dielectric layers L(1) to L(11) numbered in order from the top layer correspond to a plurality of dielectric layers included in the formation region of the wiring structure of the present invention. Although not shown in FIG. 1, two wall-shaped dielectric layers L are provided to surround the electronic components mounted on the high-frequency package 1, and the eleven dielectric layers L(1) to L(11) are provided. It may be formed on the upper part. Each dielectric layer L is formed to have a thickness according to the required electrical characteristics, and a conductor pattern unique to each is formed on the surface thereof. For example, a laminated substrate including a plurality of dielectric layers L is formed of a high temperature fired multilayer ceramic having a relatively high dielectric constant.

In the formation area of the wiring structure according to the present invention, on the surface of the uppermost dielectric layer L(1) (first dielectric layer of the present invention), a signal extended from the above-mentioned one terminal pad is provided. The wiring 10 (first signal wiring of the present invention) is formed. Further, on the back surface of the lowermost dielectric layer L(11) (the second dielectric layer of the present invention), the signal wiring 11 extending to one pad for external connection (the second dielectric layer of the present invention). Signal wiring) is formed. In the lower part of FIG. 1, for convenience, the lateral direction of the drawing is defined as the X direction (first direction of the present invention), the stacking direction of the plurality of dielectric layers L is defined as the Z direction, and the X direction and the Z direction are indicated by arrows. It is shown in. It should be noted that the + (plus) side direction of the X direction is the left direction, and the-(minus) side direction of the X direction is the right direction. Further, the + (plus) side direction of the Z direction is the upward direction, and the − (minus) side direction of the Z direction is the downward direction. Similarly, in the lower part of FIG. 2, the direction orthogonal to the X direction in plan view (the direction perpendicular to the paper surface of FIG. 1) is defined as the Y direction, and the X direction and the Y direction are indicated by arrows. Therefore, each of the upper and lower signal wirings 10 and 11 is a transmission line extending in the X direction.

The upper and lower signal wirings 10 and 11 are electrically connected to each other through a plurality of via conductors that penetrate the dielectric layers L(1) to L(11) in the Z direction, and the signal wiring 10 to the signal wiring 11 are connected to each other. Signal transmission is possible. As shown in FIG. 1, the via portion formed of the plurality of via conductors extends linearly along the Z direction through the five dielectric layers L(4) to L(8) at the center in the Z direction. The linear via part 20, the oblique via part 21 extending obliquely through the upper three dielectric layers L(1) to L(3), and the lower three dielectric layers L(9) to L(L). It is divided into diagonal via portions 22 that extend diagonally through (11). Although the number of the plurality of via conductors is not particularly limited, for example, one via conductor is formed in each of the eleven dielectric layers L(1) to L(11), and the vias vertically adjacent to each other are formed. When the conductors are connected to each other via the connection conductor, eleven via conductors are connected in multiple stages.

In FIG. 1, four connection points N1, N2, N3, N4 are shown. That is, from the top, the signal wiring 10 and the upper end of the diagonal via part 21 are sequentially connected via the connection point N1 (first connection point of the present invention), and the lower end of the diagonal via part 21 is connected via the connection point N2. And the upper end of the linear via part 20 are connected, the lower end of the linear via part 20 and the upper end of the oblique via part 22 are connected via a connection point N3, and a connection point N4 (the second connection point of the present invention) The lower end portion of the diagonal via portion 22 and the signal wiring 11 are connected via the. Here, focusing on the positions of the connection points N1 to N4 in the X direction, the pair of connection points N2 and N3 are located at the center in the X direction as shown in FIG. Are separated by a distance X1 on the right side, and the connection point N4 is separated by a similar distance X1 on the left side. In the example of FIG. 1, the pair of upper and lower diagonal via portions 21 and 22 have the same length in the Z direction and the X direction, and extend at the same angle in the XZ plane.

Note that the pair of diagonal via portions 21 and 22 may be different from each other in the distance in the X direction and the angle in the stretching direction without being limited to the structure of FIG. 1. However, the positions of the terminal pad, the connection point N1, the connection points N2 and N3 (the position of the linear via portion 20 in plan view), the connection point N4, and the pad for external connection are sequentially arranged in this order along the X direction in a plan view. It is necessary to shift it. If the arrangement deviates from this, one or both of the signal wirings 10 and 11 may become too long, or the transmission direction of the high-frequency signal may be inverted in the X direction. Further, the linear via portion 20 is not limited to being exactly parallel to the Z direction, but may be substantially parallel to the Z direction as long as impedance matching can be ensured.

Further, in FIG. 1, the signal wiring 10 on the upper layer side and the signal wiring 11 on the lower layer side are entirely extended linearly in the X direction, but the signal wirings 10 and 11 are partially extended in the X direction. It suffices if it includes an extended line portion. For example, when the positions of the connection point N1 of the signal wiring 10 on the upper layer side and the terminal pads for electronic parts are slightly displaced in the Y direction, or when the connection point N4 of the signal wiring 11 on the lower layer side and the external connection are externally connected. It is assumed that the positions of the pads for use are slightly displaced in the Y direction.

Around each dielectric layer L, a ground conductor 12 electrically connected to a common ground is formed. As shown in FIG. 2, a circular ground conductor removal region 13 having a diameter D is provided in the center of the ground conductor 12, and the ground conductor 12 is removed only inside the ground conductor removal region 13. On the eleven dielectric layers L(1) to L(11), the ground conductor 12 and the ground conductor removal region 13 are formed so as to overlap each other in a plan view.

Further, as shown in FIG. 2, each of the dielectric layers L includes a plurality of ground conductors (10 in FIG. 2) arranged so as to surround the circular ground conductor removal region 13 of the ground conductor 12. A ground via conductor group 23 composed of via conductors is formed. As shown in FIG. 1, the respective via conductors of the ground via conductor group 23 are arranged at the same position of the dielectric layers L of the respective layers, and are penetrated in the Z direction and connected in multiple stages. When seen in a plan view, the linear via portion 20 and the diagonal via portions 21 and 22 described above are located within the circular ground conductor removal region 13, so that the ground conductor 12 surrounds the periphery thereof.

In FIG. 2, the ground via conductor groups 23 arranged in the ground conductor 12 are all arranged in the vicinity of the circular ground conductor removal region 13, but the ground via conductor groups distributed over the entire ground conductor 12 are arranged. By arranging 23, the ground of the high frequency package 1 may be strengthened.

As an example of dimensions of the wiring structure shown in FIG. 1 and FIG. 2, for example, the diameter D of the ground conductor removal region 13 is D=1.25 mm, and each of the connection points N1 and N4 is separated from the outer periphery of the ground conductor removal region 13. The via diameter of each of the linear via portion 20 and the diagonal via portions 21 and 22 can be set to about 0.11 mm by setting the inside diameter of 0.15 mm.

When a high-frequency signal is transmitted using the wiring structure shown in FIGS. 1 and 2, the high-frequency signal output from the terminal of the electronic component is transmitted from the signal wiring 10 on the upper layer side to the diagonal via portion 21, the straight via portion 20, and the diagonal via portion 20. After passing through the via portion 22 in this order, the signal is transmitted to the signal wiring 11 on the lower layer side and reaches the pad for external connection. Here, paying attention to the upper and lower signal wirings 10 and 11, the portion facing the ground conductor 12 is easy to ensure impedance matching as a coplanar line structure, while the portion facing the ground conductor removal region 13 is affected by the inductance component. It is easy to cause impedance mismatch. Therefore, it is desirable to shorten the portions of the upper and lower signal wirings 10 and 11 facing the ground conductor removal region 13 as short as possible. If all of the plurality of via conductors are linear along the Z direction, it is necessary to extend the signal wirings 10 and 11 to the center of the ground conductor removal region 13. However, in the present embodiment, by providing the pair of upper and lower diagonal via portions 21 and 22, the length of the signal wirings 10 and 11 can be configured to be shorter than the center of the ground conductor removal region 13 by the distance X1. Therefore, the inductance component of the signal wirings 10 and 11 can be reduced accordingly.

Further, focusing on the linear via portion 20 and the diagonal via portions 21 and 22, while the linear via portion 20 is surrounded by the ground conductors 12 and the ground via conductor groups 23 of the respective layers in a symmetrical arrangement, the diagonal via portions are inclined. Reference numerals 21 and 22 are arranged asymmetrically with respect to the ground conductor 12 and the ground via conductor group 23 of each layer. Therefore, as compared with the straight via portion 20, it is difficult to ensure the impedance matching of the diagonal via portions 21 and 22. Therefore, in this embodiment, the impedance matching of the diagonal via portions 21 and 22 is ensured by appropriately setting the cross-sectional area of the diagonal via portions 21 and 22 in the XY plane.

Further, as a conventional structure of a plurality of via conductors, for example, a structure in which all of the plurality of via conductors are obliquely arranged as disclosed in Patent Document 3 or disclosed in Patent Documents 1 and 4, for example. There is known a structure in which vertically adjacent via conductors among a plurality of via conductors are connected via connection conductors at different positions in the X direction. However, according to the structure of Patent Document 3, since there is no portion corresponding to the linear via portion 20 of FIG. 1 and a long distance is extended in an oblique direction, the impedance varies depending on the position of the via conductor, which makes impedance matching difficult. .. Further, according to the structures of Patent Documents 1 and 4, multiple reflection from a location where a plurality of via conductors are discontinuously connected in the X direction cannot be avoided. On the other hand, according to the structure of the present embodiment, since the length of the oblique via portions 21 and 22 is limited as described above, it is easy to ensure impedance matching as a whole, and the connection points N1, N2, N3, Since there are no connection points discontinuous in the X direction including N4, the above-mentioned multiple reflection can be avoided. Specific high-frequency characteristics and impedance characteristics based on the wiring structure of this embodiment will be described later.

Note that the wiring structures shown in FIGS. 1 and 2 are examples, and the present invention can be applied without being limited to such structures. For example, in FIG. 1, of the eleven dielectric layers L(1) to L(11), the linear via portions 20 are formed in a range of five layers, and each of the oblique via portions 21 and 22 corresponds to three layers. However, the number of stacked layers may be changed. Considering the high frequency characteristics based on the wiring structure of the present embodiment, each of the oblique via portions 21 and 22 is formed in a portion having a thickness in the range of 15 to 30% with respect to the total thickness, and the linear via portion 20 is formed. Is preferably formed in the remaining portion.

FIG. 3 shows a modification of the wiring structure shown in FIG. 1, in which each of the formation portions of the diagonal via portions 21 and 22 has a thickness in the range of 15 to 30% of the whole as described above. Note that, in FIG. 3, in the wiring structure of FIG. 1, a configuration other than the eleven dielectric layers L(1) to L(11), the signal wirings 10 and 11, the straight via portion 20, and the diagonal via portions 21 and 22 is provided. The elements are not shown because they are the same as those in FIG. Specifically, the linear via portion 20 penetrates the seven dielectric layers L(3) to L(9), and the upper oblique via portion 21 has two dielectric layers L(1) and L(2). And the lower diagonal via portion 22 penetrates the two dielectric layers L(10) and L(11).

However, taking the wiring structure of FIG. 1 as an example, the number of stacked layers in the range where each of the diagonal via portions 21 and 22 penetrates is set to one layer or four layers or more in each of the above 15 to 30% range. Therefore, it is not preferable from the viewpoint of good high frequency characteristics. In the case of the wiring structure of FIG. 1, the condition that the formation range of the oblique via portions 21 and 22 is in the range of 15 to 30% is limited to the number of laminated layers being 2 layers (FIG. 3) or 3 layers (FIG. 1). .. However, if the number of laminated dielectric layers L or the thickness of each dielectric layer L is changed, the above-described condition may be satisfied even if the number of laminated layers is one or four or more. With respect to this condition, if the range in which each of the diagonal via portions 21 and 22 is formed is relatively short, the impedance cannot be matched due to the influence of the inductance component. On the other hand, when the range in which each of the oblique via portions 21 and 22 is formed is relatively long, the range in which the linear via portion 20 is formed becomes short, and in either case, high frequency characteristics are deteriorated.

Further, although the cross-sectional shapes and the directivities of the upper and lower diagonal via portions 21 and 22 may be different from each other, there are restrictions on the positions in the X direction of the connection points N1 to N4 in FIGS. 1 and 2. In the example of FIG. 1, the position of the connection point N1, the positions of the connection points N2 and N3, and the position of the connection point N4 are measured along the + (plus) X direction from the end (right end) of the signal line 10 as described above. , The signal wiring 11 is arranged in such a manner that it is sequentially displaced like the end (left end). In this example, the position of the connection point N1 is located on the left side of the positions of the connection points N2 and N3 (the signal wiring 10 extends in the −(minus) X direction from the connection point N1 to the connection point N2) or the connection point N4. In the arrangement in which the position is on the right side of the positions of the connection points N2 and N3 (the signal wiring 11 extends in the −(minus) X direction from the connection point N3 to the connection point N4), the length of the signal wirings 10 and 11 becomes long. Not preferable. Further, the arrangement is such that the positions of the connection points N1 and N4 are on the same side as the connection points N2 and N3 (the signal wiring 10 extends in the + (plus) X direction from the connection point N1 to the connection point N2 and is connected from the connection point N3. The signal wiring 11 extending in the −(minus)X direction up to the point N4) is also not preferable from the viewpoint of the transmission direction of the signal wirings 10 and 11.

1 and 2, the wiring structure that constitutes one transmission line is shown. However, when a plurality of transmission lines are configured, the structures of FIGS. 1 and 2 are arranged in parallel in the high frequency package 1. It is only necessary to form a plurality. For example, in the case of configuring a differential transmission line, the structures of FIGS. 1 and 2 may be symmetrically arranged and two types of transmission lines may be configured to pass through the structures.

Next, the electrical characteristics of the high frequency package 1 of the present embodiment will be described with reference to FIGS. In the following, as a comparative example for comparison with the electrical characteristics of the wiring structure of the present embodiment, a conventional wiring structure in which a plurality of via conductors are entirely extended in an oblique direction is assumed. FIG. 4 relates to a comparative example having the wiring structure of Patent Document 3, and relates to upper and lower signal wirings via diagonal via portions 30 formed of all via conductors penetrating eleven dielectric layers L(1) to L(11). The schematic sectional drawing of the structure where 10 and 11 is electrically connected is shown. 4, the components other than the eleven dielectric layers L(1) to L(11) and the signal wirings 10 and 11 in the wiring structure of FIG. 1 are not different from those of FIG. doing.

FIG. 5 shows the verification result of the S parameter of the comparative example (FIG. 4), and FIG. 6 shows the verification result of the S parameter of the present embodiment (FIG. 1). In FIGS. 5 and 6, the frequency characteristic of the S parameter was verified by simulation for the transmission line from the terminal of the electronic component to the pad for external connection via each wiring structure in the frequency range of 40 GHz or less. It is a thing. The S parameters include S11 and S22 indicating the reflection characteristics and S21 indicating the transmission characteristics, and the quality of the high frequency characteristics can be determined mainly based on the S parameters S11 and S22. The diagonal via portion 30 used in FIG. 5 and the linear via portion 20 and the diagonal via portions 21 and 22 used in FIG. 6 have a via diameter set to 0.11 mm in the XY plane. ..

First, in the comparative example shown in FIG. 5, it can be seen that the deterioration of the reflection loss (S11, S22) is remarkable particularly in the high frequency band exceeding 20 GHz, which is insufficient as the transmission characteristic of the high frequency signal. On the other hand, in the present embodiment shown in FIG. 6, the reflection loss can be suppressed over a wide frequency range, and the transmission characteristic of the high frequency signal can be improved as compared with FIG. This is because the structure in which the straight via portion 20 and the diagonal via portions 21 and 22 are connected to each other as described above avoids multiple reflection, and shortens the diagonal via portions 21 and 22 to suppress the influence of impedance mismatch. This is due to the effect of that.

Next, FIG. 7 shows the impedance verification result of the comparative example (FIG. 4), and FIG. 8 shows the impedance verification result of the present embodiment (FIG. 1). 7 and 8, the impedance characteristics at each position of the signal wiring and the via conductor are verified by simulation under the same conditions as in the cases of FIGS. 5 and 6. 7 and 8, the pulse signal is input from the terminal pad side for the electronic component, and the impedance calculated based on the reflection signal from each position of the signal wiring and the via conductor to the terminal side is shown. In addition, in FIG. 7, as a time region section corresponding to the distance from the input position of the pulse signal, a portion (region of the signal wiring 10), b portion (region of the oblique via portion 30 near the signal wiring 10), The section c (the central area of the oblique via section 30), the section d (the area of the oblique via section 30 near the signal wiring 11), and the section e (the area of the signal wiring 11) are shown.

In general, it is premised that the characteristic impedance of the transmission line is designed to be 50Ω, and in this case it is ideal to keep 50Ω over the entire time range. In both the characteristics of FIG. 7 and FIG. 8, the impedance variation increases in a specific part of the time range, but this mainly reflects the distance from the input part to the connection points such as the connection points N1 to N4. ing. However, as compared with the comparative example shown in FIG. 7, in the present embodiment shown in FIG. 8, the fluctuation range of the impedance is relatively small, and in combination with the above-described S parameter verification result, the wiring structure of the present embodiment is obtained. It was confirmed that the adoption of is effective in improving the high frequency characteristics.

Regarding the electrical characteristics of the high frequency package 1 of this embodiment, in FIGS. 6 and 8, the via diameters in the XY plane of the linear via portion 20 and the diagonal via portions 21 and 22 are in the XY plane as described above. Although the example is set to 0.11 mm, the via diameters of the oblique via portions 21 and 22 may be slightly increased as compared with the straight via portion 20. By increasing the via diameter of the diagonal vias 21 and 22, the inductance component decreases and the capacitance component increases, so that the impedance can be lowered. In this case, since the optimum via diameters of the straight via portion 20 and the diagonal via portions 21 and 22 are determined by various factors such as the frequency of the high frequency signal and the manufacturing conditions of the high frequency package 1, it can be appropriately adjusted based on, for example, a simulation. desirable. Further, as in the wiring structure of FIG. 1, it is most preferable that the number of the laminated layers of the diagonal via portions 21 and 22 is three layers among the eleven dielectric layers L(1) to L(11). Although high frequency characteristics can be obtained, the optimum number of layers may change depending on the various factors mentioned above.

Although the content of the present invention has been specifically described based on the present embodiment, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, various electronic components including a semiconductor chip can be used as the electronic components mounted on the high frequency package 1 of the present embodiment. Further, in the high frequency package 1 of the present embodiment, the number of layers of the dielectric layers L and the constituent materials can be variously selected. In other respects, the content of the present invention is not limited to the above-described embodiment, and the content disclosed in the above-described embodiment is not limited as long as the effect of the present invention can be obtained, and can be appropriately changed. is there.

DESCRIPTION OF SYMBOLS 1... High frequency package 10, 11... Signal wiring 12... Ground conductor 13... Ground conductor removal area 20... Straight via part 21, 22... Oblique via part 23... Ground via conductor group L... Dielectric layers N1, N2, N3, N4 … Junction

Claims (5)

A high frequency package capable of mounting electronic components on a laminated substrate including a plurality of laminated dielectric layers,
In a plan view, a first pad extending in a first direction from a terminal pad connected to a terminal of the electronic component to a first connection point formed on a first dielectric layer of the plurality of dielectric layers. Signal wiring,
A second signal wiring extending in the first direction from a second connection point formed on the second dielectric layer of the plurality of dielectric layers to a pad for external connection in plan view;
A plurality of via conductors that penetrate the plurality of dielectric layers in the stacking direction and electrically connect the first connection point and the second connection point;
A ground conductor formed in each of the plurality of dielectric layers and surrounding a region in which the plurality of via conductors are arranged in a plan view,
Equipped with
The plurality of via conductors are
From the upper end formed in the dielectric layer below the first dielectric layer to the lower end formed in the dielectric layer above the second dielectric layer, along the stacking direction. And a linear via part that extends linearly,
A first diagonal via portion extending diagonally from the first connection point to the upper end portion of the linear via portion;
A second diagonal via portion extending diagonally from the second connection point to the lower end portion of the linear via portion;
Including
The first signal wiring is formed on one surface of the laminated board, and the second signal wiring is formed on the other surface of the laminated board,
The first connection points, the linear via portions, and the second connection points are arranged at positions that are sequentially displaced along the first direction in a plan view.
High frequency package characterized by The high frequency wave according to claim 1, wherein each of the first and second diagonal via portions is a via portion that penetrates two or three dielectric layers of the plurality of dielectric layers. package. A portion in which each of the first and second diagonal via portions is formed has a thickness in a range of 15% to 30% with respect to a total thickness of the plurality of dielectric layers. The high frequency package according to claim 1 or 2. The high frequency package according to claim 1, wherein the via diameters of the first and second diagonal via portions are set to be the same as or slightly larger than the via diameter of the linear via portion in a plan view. .. The high frequency package according to claim 4, wherein the diameter of each of the straight via portion and each of the first and second diagonal vias is set so as to have a desired characteristic impedance.

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