JPH118444A - High-frequency electric wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-frequency electric wiring board which can make small variations in the propagation time of a high-frequency signal between high-frequency electric wiring lines, to lessen deterioration of high frequency characteristics of a semiconductor element using the high-frequency signal and a transmission error thereof. SOLUTION: In a high-frequency electric wiring board 102 which comprises at least an electric wiring insulating layer 106 and a plurality of high frequency electric wiring lines 104, for increasing or decreasing a pitch between the high- frequency electric wiring lines, at least one curved part 124 is provided in the middle of some of the high-frequency electric wiring lines, so that the lengths of the electric wiring lines become substantially equal to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for high-frequency electric wiring for increasing or decreasing the pitch of high-frequency electric wiring, and more particularly, to a high-frequency electric wiring having substantially the same propagation time of a high-frequency signal in each high-frequency electric wiring. For substrates.

[0002]

2. Description of the Related Art Conventionally, a high-frequency electric wiring substrate for increasing or decreasing the pitch of a high-frequency electric wiring has been developed. A module of a laser diode array using a film carrier as the high-frequency electric wiring substrate has been disclosed by Mitsuo Usui et al. "Nobel Packaging Technique for Laser Diode Arrays Using Film Carrier, ECTC, pp. 818-824, 1
993 ".

Prior to describing the present invention, the structure of this film carrier (high-frequency electric wiring substrate) 12 will be described with reference to FIG. That is, the film carrier 12 is made of an electric insulating layer 16 made of a polyimide film.
And a plurality of high-frequency electrical wirings 14. Further, each high-frequency electric wiring 14 is composed of only a straight portion, and one end of the high-frequency electric wiring is referred to as an inner lead 14f of the high-frequency electric wiring and the other end is referred to as an outer lead 14g.

[0004] Each of these high-frequency electric wires is provided on the surface of the electric insulating layer 16 with an outer lead 14 g (pitch 1).
250 μm) to inner lead 14 f (pitch 125 μm)
m), the pitch (the distance from the center of each wiring between adjacent high-frequency electrical wirings) to 1/10 is reduced. Grounds 30 are provided on both sides of the arrangement of the high-frequency electrical wirings 14 and on the back side of the electrical insulating layer 16, respectively. Further, bumps 28 are provided at the tips of the inner leads 14f of each high-frequency electrical wiring 14. It is.

Accordingly, as shown in FIG. 10, the film carrier 12 is turned over, the high-frequency electric wiring 14 and the laser diode array 24 are opposed to each other, and the inner leads 14 of the high-frequency electric wiring 14 are
f and terminals of the laser diode array 24 are electrically connected.

Therefore, from a high frequency power supply (not shown),
Each high-frequency electric wiring 1 in this film carrier 12
When predetermined high-frequency signals are applied in parallel to the four outer leads 14g, these high-frequency signals are transmitted to the inner leads 14f of the respective high-frequency electric wirings 14 through the respective high-frequency electric wirings 14 having different lengths. These high-frequency signals are transmitted from the inner leads 14f to the laser diode array 24 via the bumps 28, and each of the laser diodes (four rows) constituting the laser diode array 24 can be oscillated.

FIG. 11 shows a laser diode array module assembled using a conventionally known high-frequency electric wiring substrate 52 for enlarging or reducing the pitch (arrangement pitch) of another high-frequency electric wiring. 50 is shown. Note that the laser diode array module 50 is shown as a configuration when viewed from above in a planar direction with the cover of the package 60 removed.

The high-frequency electric wiring board 52 includes an electric insulating layer 56 made of a polyimide film and a plurality of high-frequency electric wirings 54 (54a, 54b, 54c, 54) having different lengths.
d, 54e).

However, unlike the conventional high-frequency electric wiring substrate (film carrier) described above, no bump is provided on the inner lead 54f of each high-frequency electric wiring 54, and each of the high-frequency electric wiring 54 and the laser diode The terminals of the array 64 are electrically connected using bonding wires 58. Therefore, when a predetermined high-frequency signal is applied in parallel to the outer lead 54 g of each high-frequency electric wiring 54, these high-frequency signals pass through each high-frequency electric wiring 54 having a different length, and It is transmitted to each of the leads 54f.

These high-frequency signals are transmitted to the laser diode array 64 via the bonding wires 58, and each laser diode (five rows) constituting the laser diode array 64 emits laser light (oscillates). Therefore, in the laser diode array module 50, the laser light oscillated by each can be extracted as an optical signal to the outside by the optical fiber 72.

[0011]

However, in the conventional high-frequency electric wiring substrate, the high-frequency electric wiring formed on the electric insulating layer is entirely composed of only a straight portion. The length of each high-frequency electric wiring along each high-frequency electric wiring (in this case, the length of each high-frequency electric wiring is equal to the linear distance) differs depending on the enlargement rate or reduction rate of the pitch of the outer leads. I have.

Therefore, when a high-frequency signal is input in parallel to the outer lead of the high-frequency electric wiring from a high-frequency power supply (not shown), the high-frequency signal is input to the high-frequency electric wiring and then used. Semiconductor elements,
For example, the time required to reach the laser diode array (propagation time) is deviated, and variations among the high-frequency electrical wirings are likely to occur. Therefore, in the laser diode array electrically connected to the inner lead side of each high-frequency electric wiring, there is a problem that the operation range for identifying high-frequency signals (the time range in the propagation time of the identifiable high-frequency signal) is likely to be narrowed. That is, in the worst case, there is also a problem that a transmission error occurs due to a variation in propagation time between the high-frequency electrical wirings.

In particular, in recent years, the pitch and line width of the high-frequency electric wiring on the inner lead side have been narrowed with the miniaturization and large-scale integration of the semiconductor element mounted on the substrate for high-frequency electric wiring. With respect to a substrate for high-frequency electric wiring for enlarging or reducing the pitch of electric wiring, the rate of expansion or reduction of the pitch of high-frequency electric wiring is increasing.

Therefore, the length of each high-frequency electrical wiring becomes more and more different according to the enlargement or reduction ratio of the pitch of the high-frequency electrical wiring, and the variation in the propagation time of the high-frequency signal between the high-frequency electrical wirings is promoted. As a result, the problems of the high-frequency characteristics of the semiconductor element and the transmission error due to the variation in the propagation time of the high-frequency signal have become serious.

Therefore, in the high-frequency electric wiring board for enlarging or reducing the pitch of the high-frequency electric wiring, the variation in the propagation time of the high-frequency signal between the high-frequency electric wirings is small, and the high-frequency of the semiconductor element utilizing this high-frequency signal is high. There has been a demand for a high-frequency electrical wiring substrate that has less problems of characteristic deterioration and transmission errors.

[0016]

According to the high-frequency electric wiring substrate of the first embodiment of the present invention, the pitch of the high-frequency electric wiring constituted by at least the electric insulating layer and the plurality of high-frequency electric wirings is enlarged or In the high-frequency electric wiring board for reduction, at least one curved portion is provided in the middle of the high-frequency electric wiring so that the lengths of the plurality of high-frequency electric wirings along the respective high-frequency electric wirings are substantially equal. It is characterized by being provided.

As described above, when at least one curved portion is provided in the middle of the high-frequency electric wiring, a distance (linear distance) connecting one end of the high-frequency electric wiring and the other end linearly depends on the size and number of the curved portions. ) Can easily adjust the length of each high-frequency electric wiring.

Accordingly, the lengths of the high-frequency electrical wires having different linear distances can be made substantially equal. Therefore, the high-frequency characteristics of the semiconductor element using this high-frequency signal caused by the difference in the length (linear distance) between the high-frequency signals, that is, by the variation in the propagation time of the high-frequency signal in each high-frequency signal. Degradation and transmission errors can be effectively prevented.

The length of the high-frequency electric wiring when such a curved portion is provided on the high-frequency electric wiring can be easily measured by using a CAD or the like. Also, CA
By using D or the like, it is possible to prevent the occurrence of crosstalk by increasing the distance between adjacent high-frequency electrical wirings as much as possible. Therefore, the first of the present invention
In the high-frequency electric wiring board according to the embodiment, the difficulty in designing such high-frequency electric wiring is not particularly problematic.

Here, the linear distance of the high-frequency electric wiring means a distance between one end of the high-frequency electric wiring and the other end by a straight line, that is, from one end of the high-frequency electric wiring to the other end. When assuming that a straight line was drawn toward,
It means the length (distance) of the straight line.

For example, the length of a straight line indicated by an arrow along the high-frequency electric wires 54a, 54b, 54c in FIG. 11 is referred to as a linear distance of the high-frequency electric wires. Therefore,
In a high-frequency electric wiring board for enlarging or reducing the pitch of the high-frequency electric wiring, in order to use the high-frequency electric wiring board effectively by minimizing a difference in length of each high-frequency electric wiring, a horizontal direction is generally used. Among the plurality of high-frequency electric wirings arranged in the above, the linear distance of the high-frequency electric wiring near the center is the shortest, and the linear distance is longer as the high-frequency electric wiring is arranged farther from the vicinity of the center.

Further, the length of the high-frequency electric wiring is defined as a curve between the high-frequency electric wiring and one end of the high-frequency electric wiring. (The straight line distance and the length of the high-frequency electric wiring coincide with each other), and this curve (straight line) when connected by a curve (when the high-frequency electric wiring is linear, it becomes a straight line).
Say the length (distance) of For example, the length (distance) of each curve (including a straight line) represented by an arrow shown along the high-frequency electric wires 104a, 104b, and 104c in FIG.
Is called the length of each high-frequency electric wiring.

In the present invention, when the length or the linear distance of the high-frequency electrical wiring is referred to, the length or the linear distance of the inner lead and the outer lead of the high-frequency electrical wiring located at both ends of the high-frequency electrical wiring is defined as: It means the length (distance) included. In this regard, the same applies to the high-frequency electrical wiring substrates of the second and third embodiments as well as the high-frequency electrical wiring substrate of the first embodiment.

In the high-frequency electric wiring board according to the first embodiment of the present invention, preferably, the curved portion provided for adjusting the length of the high-frequency electric wiring is constituted by a curved line. good.

When the curved portion is formed by a curved line, there is no corner formed by an acute angle or an obtuse angle in the middle of the high-frequency electric wiring, so that the high-frequency characteristics of the high-frequency signal are degraded or the adjacent high-frequency electric wiring is There is less possibility that crosstalk will occur between them.

In the high-frequency electric wiring board according to the first embodiment of the present invention, preferably, the curved portion provided for adjusting the length of the high-frequency electric wiring is a circle (arc), an elliptic curve or a spline curve. It is good to be constituted by.

These circles (arcs), elliptic curves and spline curves are characterized in that they have a certain regularity among the curves. Therefore, when the curved portion is formed by these curves, it is possible to arrange the curved portion in the high-frequency electric wiring so that the occurrence of crosstalk with the adjacent high-frequency electric wiring does not become a problem. Becomes easier. In addition, since the size of a circle (arc), elliptic curve, or spline curve can be obtained by calculation, the length of each high-frequency electric wiring may be accurately adjusted.

Next, a high-frequency electric wiring board according to a second embodiment of the present invention will be described. That is, the high-frequency electric wiring board according to the second embodiment of the present invention is a high-frequency electric wiring board for enlarging or reducing a pitch of a high-frequency electric wiring constituted by at least an electric insulating layer and a plurality of high-frequency electric wirings. The electrical insulating layer is divided between adjacent high-frequency electrical wires along the high-frequency electrical wires so that the propagation times of the high-frequency signals in the plurality of high-frequency electrical wires are substantially equal.
The relative permittivity of each of the divided electric insulating layers is changed in accordance with the length of each high-frequency electric wiring, and the shorter the distance (linear distance) between one end of the high-frequency electric wiring and the other end is linearly connected, the shorter the distance. In addition, the relative dielectric constant of a corresponding electric insulating layer is increased.

As described above, when the electric insulating layer is divided between the adjacent high-frequency electric wirings along the high-frequency electric wiring, the divided electric insulating layer is formed corresponding to the length of each high-frequency electric wiring. The type of material used can be easily changed. Then, the high-frequency signal travels not only in the high-frequency electric wiring but also inside the electric insulating layer. Therefore, when the relative dielectric constant of each electrical insulating layer is εn, the relative dielectric constant εn of each electrical insulating layer can be easily changed by changing the type of the material forming the electrical insulating layer.

The propagation time of this high-frequency signal is
(Εn) is proportional to the value of ^1/2 . Therefore, in accordance with the length of each high-frequency electric wiring, the relative dielectric constant of the divided electric insulating layer is determined by the length of a straight line (linear distance) when one end of the high-frequency electric wiring is connected to the other end with a straight line. The shorter the distance, the greater the relative dielectric constant of the electrical insulating layer, so that the propagation time of the high-frequency signal in each high-frequency electrical wiring can be substantially equalized.

Furthermore, in the high-frequency electric wiring board according to the second embodiment of the present invention, the interval (pitch) between each high-frequency electric wiring and the adjacent high-frequency electric wiring can be made relatively large, so that the adjacent high-frequency electric wiring can be formed. There is little possibility that crosstalk will occur between the electric wires.

The subscript n in the relative dielectric constant εn is:
It means that it corresponds to the n-th electric insulating layer from the left end among the electric insulating layers corresponding to each high-frequency electric wiring.

In the high-frequency electric wiring board according to the second embodiment of the present invention, preferably, the length of the high-frequency electric wiring is Ln, and the relative dielectric constant of the electric insulating layer corresponding to the high-frequency electric wiring is εn. Then, the propagation time T of the high-frequency signal in each high-frequency electrical wiring represented by the following equation (1)
Preferably, n is substantially equal to each other.

[0034]

(Equation 8)

Where c is the speed of light in vacuum (about 3 ×
10 ⁸ m / s), and the subscript n in each symbol is
It means that it corresponds to the n-th high-frequency electric wiring from the left end in each high-frequency electric wiring.

As described above, the ratio of the electric insulating layer corresponding to the length of the high-frequency electric wiring is determined by the equation (1) so that the propagation time Tn of the high-frequency signal in each high-frequency electric wiring is substantially equal. If the dielectric constant εn is selected, it is possible to more reliably solve the problem of the deterioration of the high-frequency characteristics and the transmission error of the semiconductor element using the high-frequency signal due to the variation of the propagation time of the high-frequency signal in each high-frequency electrical wiring. Can be.

In the high-frequency electric wiring board according to the second embodiment of the present invention, preferably, the electric insulating layer comprises:
It is good to divide also in the direction which intersects with the corresponding high-frequency electric wiring. The relative dielectric constant of at least one electrical insulating layer of the electrical insulating layer divided in a direction crossing the high-frequency electrical wiring is preferably different from the relative dielectric constant of the other electrical insulating layers.

As described above, when the electric insulating layer is divided also in the direction crossing the corresponding high-frequency electric wiring, the material constituting the divided electric insulating layer can be changed more finely. Therefore, various kinds of materials for the electric insulating layer can be used, and the relative dielectric constant of the electric insulating layer can be changed more easily according to the length of each high-frequency electric wiring, and the propagation of the high-frequency signal can be performed. This is preferable in that the time can be equalized.

Next, a high-frequency electric wiring board according to a third embodiment of the present invention will be described. That is, the high-frequency electrical wiring board according to the third embodiment of the present invention is a high-frequency electrical wiring board for increasing or decreasing the pitch of the high-frequency electrical wiring, and includes at least an electrical insulating layer and a plurality of high-frequency electrical wirings. In the configured high-frequency electric wiring substrate, a predetermined interval (gap) is provided on both sides of the high-frequency electric wiring on the surface of the electric insulating layer so that the high-frequency electric wiring forms a coplanar line with a ground. A first ground is provided in parallel with the electric wiring.

In the high-frequency electric wiring board according to the present invention, a second ground is provided on the back surface of the electric insulating layer so that the propagation time of the high-frequency signal in each high-frequency electric wiring is substantially equal. The distance between the high-frequency electric wiring and the first ground is increased as the distance (linear distance) between one end of the high-frequency electric wiring and the other end is reduced.

When the high-frequency electric wiring is constituted by the coplanar line with the ground, the high-frequency electric wiring can be easily formed by changing the gap (gap) between the high-frequency electric wiring and the first ground provided on both sides. The propagation time of the high-frequency signal in the wiring can be made substantially equal. That is, the high-frequency electrical wiring and the first
Since the distance (gap) to the ground and the effective relative permittivity have a certain relationship as described later, the distance (gap) between the high-frequency electrical wiring and the first ground provided on both sides is changed. Thereby, the effective relative permittivity corresponding to the high-frequency electric wiring can be easily changed.

Accordingly, the propagation time of the high-frequency signal and the effective relative permittivity have a relationship represented by the equation (2), as will be described later. Can be made substantially equal only by changing the gap (gap) between each high-frequency electric wiring and the first ground provided on both sides.

In the high-frequency electric wiring board, when the high-frequency electric wiring is constituted by a coplanar line with a ground as in the present invention, as described later, the characteristic impedance Zn of each high-frequency electric wiring (the suffix n is Means that it corresponds to the n-th high-frequency electrical wiring from the left end of each of the high-frequency electrical wirings.) Can be substantially equalized by impedance matching. Preferred for the invention.

In the present invention, the distance (gap) between each high-frequency electrical wiring and the first ground provided on both sides is equal unless otherwise specified. On the premise of this, it means one value of the interval (gap) provided on both sides.

Further, the high-frequency electric wiring board according to the third embodiment of the present invention is preferably arranged such that straight lines of the high-frequency electric wiring are arranged such that propagation times of high-frequency signals in the respective high-frequency electric wirings are substantially equal to each other. It is preferable that the shorter the distance, the wider the high-frequency electric wiring.

That is, in the high-frequency electric wiring board of the third embodiment, as described above, the high-frequency electric wiring is constituted by the coplanar line with the ground. Also, the propagation time of high-frequency signals in each high-frequency electrical wiring can be easily
Can be substantially equal.

The reason for this will be described in more detail. The narrower the width of the high-frequency electric wiring, the smaller the effective relative permittivity. Therefore, by changing the width of the high-frequency electric wiring, the effective ratio corresponding to each high-frequency electric wiring is changed. The dielectric constant can be easily changed. The propagation time of the high-frequency signal and the effective relative permittivity have a certain relationship represented by Expression (2), as described later. Therefore, as described above, by changing the width of each high-frequency electric wiring, the propagation time of the high-frequency signal in each high-frequency electric wiring having a different length can be more easily equalized.

In the high-frequency electric wiring board according to the third embodiment of the present invention, preferably, the length of each high-frequency electric wiring is Ln, and the length of each high-frequency electric wiring is represented by the following formula (3). Assuming that the corresponding effective relative permittivity is ε _eff n, it is preferable that the propagation times Tn of the high-frequency signals in the high-frequency electrical wirings represented by the following equation (2) are substantially equal to each other.

The propagation time T in the following equation (2)
n, length Ln of high-frequency electrical wiring and effective relative permittivity ε
The suffix n of _eff n means that it corresponds to the n-th high-frequency electric wiring from the left end among the respective high-frequency electric wirings. Hereinafter, the suffix n of each symbol in each formula has the same meaning.

[0050]

(Equation 9)

Where c is the speed of light in vacuum (about 3 × 10 ⁸
m / s).

[0052]

(Equation 10)

In the formula, a is the width (μm) of the high-frequency electric wiring,
b is a value (μm) obtained by adding the distance between the high-frequency electric wiring and the first ground on both sides to the value of a, and d is the width of the first ground on both sides of the high-frequency electric wiring to the value of b. The added value (μm), h is the thickness of the electric insulating layer (μm), t
Means the thickness (μm) of the high-frequency electric wiring.

As described above, by using the equations (2) and (3), the high-frequency electric wirings are provided on both sides of the high-frequency electric wiring such that the propagation times Tn of the high-frequency signals are substantially equal. (Gap) with the first ground
If you select the width of high-frequency electrical wiring, etc.,
The propagation time of the high-frequency signal in each high-frequency electrical wiring can be made equal. Therefore, it is possible to solve the problem of the deterioration of the high frequency characteristics and the transmission error in the semiconductor element using the high frequency signal due to the variation in the propagation time of the high frequency signal in each high frequency electric wiring.

The substrate for high-frequency electric wiring according to the third embodiment of the present invention preferably has an effective relative dielectric constant ε _eff n corresponding to each high-frequency electric wiring of 2.0 to 12.0.
It is preferable to set the value within the range of (-). If the effective relative permittivity ε _eff n corresponding to each high-frequency electric wiring is a value within the range, a general electric insulating material such as an epoxy-based material, a polyimide-based material, a fluorine-based material, a phenol-based material, A polyester material, a polyamide material, a cyanate ester material, a ceramic material, and the like can be used as the material of the electric insulating layer.

Therefore, from the viewpoint of further increasing the selectivity of the electric insulating material to be used, the value of each effective relative dielectric constant ε _eff n corresponding to each high-frequency electric wiring is more preferably
Values in the range of 2.5-6.0, optimally 3.0.
A value within the range of ~ 4.0 is good.

The high-frequency electric wiring board according to the third embodiment of the present invention preferably has a characteristic impedance Zn of each high-frequency electric wiring represented by the following formula (4).
Is preferably in the range of 10 to 100 (Ω).

[0058]

[Equation 11]

In the equation, η ₀ means the wave impedance in vacuum, ie, 377 (Ω), and a,
b, t, ε _eff n, K (k ₁ ) / K (k ₁ ′), K (k
₂ ) / K (k ₂ ′) is as defined in equation (3).

Generally, the characteristic impedance of a high-frequency power supply or the like is set in the range of 50 to 60 (Ω).
If the characteristic impedance of each high-frequency electric wiring is set to a value within the above range, impedance matching with a high-frequency power supply or the like is achieved, and a reflection phenomenon of the high-frequency signal (power) is prevented, so that the high-frequency signal (power) can be effectively transmitted. This is because it can be used.

Therefore, in the high-frequency electric wiring substrate according to the third embodiment of the present invention, more preferably, the characteristic impedance Zn of each high-frequency electric wiring is set to a substantially equal value within the range of 20 to 80 (Ω). Is good.

Next, a high-frequency electric wiring board according to a fourth embodiment of the present invention will be described. That is, the high-frequency electric wiring substrate according to the fourth embodiment of the present invention is a high-frequency electric wiring substrate for increasing or decreasing the pitch of the high-frequency electric wiring, and includes at least an electric insulating layer and a plurality of high-frequency electric wirings. In the configured high-frequency electric wiring board, first grounds are respectively provided on both sides of the high-frequency electric wiring on the surface of the electric insulating layer in parallel with the high-frequency electric wiring so that the high-frequency electric wiring forms a coplanar line. It is provided.

The distance (linear distance) between one end and the other end of each high-frequency electrical wiring linearly so that the propagation time of the high-frequency signal in each of the plurality of high-frequency electrical wirings is substantially equal. The distance between the high-frequency electric wiring and the first ground is increased as the distance is shorter.

The high-frequency electric wiring board according to the fourth embodiment of the present invention is a modification of the third embodiment, and has a simpler structure than the third embodiment. That is, the second ground is not provided on the back side of the electric insulating layer, and each high-frequency electric wiring is constituted by a so-called coplanar line. Therefore, there is an advantage that manufacturing, product management, and the like of the high-frequency electric wiring board of the fourth embodiment are facilitated.

Also, in the high-frequency electric wiring substrate of the fourth embodiment, since each high-frequency electric wiring is constituted by a coplanar line, the high-frequency electric wiring is connected to both sides in the same manner as in the third embodiment. The effective relative permittivity corresponding to each high-frequency electrical wiring can be easily changed by changing the gap (gap) with the first ground provided in the first wiring.

Therefore, also in the high-frequency electric wiring board of the fourth embodiment, as described in the third embodiment, the propagation time of the high-frequency signal and the effective relative permittivity are different from each other.
Because of the relationship represented by equation (2), the propagation time of a high-frequency signal in each high-frequency electrical wiring having a different length is determined by the distance (gap) between each high-frequency electrical wiring and the first ground provided on both sides. By simply changing, each can be made substantially equal.

In the high-frequency electric wiring board according to the fourth embodiment of the present invention, preferably, the straight lines of the high-frequency electric wiring are so arranged that the propagation times of the high-frequency signals in the respective high-frequency electric wirings are substantially equal. It is preferable that the shorter the distance, the wider the high-frequency electric wiring.

That is, in the high-frequency electric wiring board of the fourth embodiment, since each high-frequency electric wiring is constituted by a coplanar line, the width of the high-frequency electric wiring is reduced as in the third embodiment. By changing, the effective relative permittivity corresponding to each high-frequency electric wiring can be easily changed. Therefore, by changing the width of the high-frequency electrical wiring, the propagation times of the high-frequency signals in the high-frequency electrical wirings having different lengths can be more easily equalized.

In the high-frequency electric wiring board according to the fourth embodiment of the present invention, preferably, the length of each high-frequency electric wiring is Ln, and the length of each high-frequency electric wiring is represented by the following formula (5). Assuming that the corresponding effective relative permittivity is ε _eff n, it is preferable that the propagation times Tn of the high-frequency signals in the high-frequency electrical wirings represented by the following equation (2) are substantially equal to each other.

[0070]

(Equation 12)

Where c is the speed of light in a vacuum (about 3 × 10 ⁸
m / s).

[0072]

(Equation 13)

Where α is the width (μm) of the high-frequency electrical wiring,
β is a value obtained by adding the value of α to the distance γ between the high-frequency electric wiring and the first grounds provided on both sides (μ
m) and h mean the thickness (μm) of the electric insulating layer.

As described above, by using the equations (2) and (5), the high-frequency electric wirings are provided on both sides of the high-frequency electric wiring such that the propagation times Tn of the high-frequency signals are substantially equal. (Gap) with the first ground
If you select the width of high-frequency electrical wiring, etc.,
The propagation time of the high-frequency signal in each high-frequency electrical wiring can be made equal.

Therefore, in the high-frequency electric wiring board of the fourth embodiment, similarly to the high-frequency electric wiring board of the third embodiment, the variation in the propagation time of the high-frequency signal in each high-frequency electric wiring is caused. It is possible to solve the problems of the deterioration of the high frequency characteristics and the transmission error in the semiconductor element using the high frequency signal.

Further, in the high-frequency electric wiring board according to the fourth embodiment of the present invention, preferably, the characteristic impedance Zn of each of the high-frequency electric wirings represented by the following formula (6):
Is preferably in the range of 10 to 100 (Ω).

[0077]

[Equation 14]

_Where the value of ε _eff n is as defined in equation (5), and K (k ') / K (k)
Means the reciprocal of the one defined in equation (5).

In this manner, also in the high-frequency electric wiring board of the fourth embodiment, the characteristic impedance of the high-frequency power supply is generally set in the range of 50 to 60 (Ω). If the characteristic impedance of the wiring is set to a value within the above range, impedance matching with a high-frequency power supply or the like can be achieved, and a reflection phenomenon of the high-frequency signal (power) can be prevented, so that the high-frequency signal (power) can be used effectively.

The high-frequency electric wiring board according to the fourth embodiment of the present invention also includes
From the viewpoint that impedance matching with a high-frequency power supply or the like can be achieved, preferably, the characteristic impedance Zn of each high-frequency electric wiring is preferably set to a substantially equal value within a range of 20 to 80 (Ω). .

The high-frequency electric wiring board according to the first to fourth embodiments of the present invention is preferably arranged such that the high-frequency electric wiring having the shortest linear distance has one bit.
Assuming the required propagation time per unit as the standard (100%),
In the high-frequency electrical wiring having the longest linear distance, the shift time of the required propagation time per bit (bit) is preferably within 25%.
If the propagation time is shifted within such a range, the dispersion of the propagation time of the high-frequency signal between the high-frequency electrical wirings is small, and the problems of the high-frequency characteristics of the semiconductor element using this high-frequency signal and the transmission error are further reduced. That's why.

Therefore, more preferably, in the high-frequency electric wiring having the longest linear distance, the shift time of the required propagation time per one bit (bit) is equal to the shift time per one bit (bit) in the high-frequency electric wiring having the shortest linear distance. The value is within 20%, optimally within 10%, based on the required propagation time (100%).

[0083]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 to 9, a high-frequency electric wiring board according to the present invention and a laser diode array as a semiconductor element using the same are mounted and assembled. An embodiment will be described. However, FIGS. 1 to 9 only schematically show the shapes, sizes, and arrangements of the components so that the present invention can be understood. Therefore, the present invention is not limited to these embodiments. Further, as the semiconductor element, various elements such as an optical modulation element and an optical switch can be mounted by using the high-frequency electric wiring substrate of the present invention, but in the following description, for convenience, the case of a laser diode array will be described. explain.

FIG. 1 is a diagram for explaining a high-frequency electric wiring board 102 according to the first embodiment of the present invention. That is, when the laser diode array 114 is mounted using the high-frequency electrical wiring substrate 102 of the present invention, and the laser diode array module 100 is assembled using the package 110 or the like, the package 110 of the module 100 The configuration is shown when the lid is removed and viewed from above.

On the bottom 110b of the package 110, a high-frequency electric wiring board 102, a heat sink 112,
After the V-groove substrate 116 is arranged at a predetermined position, it is fixed using ordinary fixing means such as solder. Then, the laser diode array 114 is connected to the heat sink 1.
12 are fixedly arranged. Therefore, even when the laser diode array 114 is driven and generates heat,
Heat can be effectively dissipated to the heat sink 112. That is, the laser diode array 114 can be maintained at a constant temperature so that the output intensity of the laser does not decrease.

On the V-groove substrate 116, along the five V-grooves, the tip of the optical fiber 122 is connected to each laser diode (114) constituting the laser diode array 114.
a, 114b, 114c, 114d, 114e), five optical fibers 122 are arranged at predetermined intervals. That is, each laser diode (114a, 114b, 114c, 114d, 11
The laser light emitted from the light emitting point of 4e) is applied to each optical fiber (122a, 122b, 122) of the optical fiber 122.
The optical axes of the laser diode array 114 and the optical fiber 122 are aligned so that they can be accurately input through the tips of c, 122d and 122e).

The arrangement of the optical fibers 122 is
After the alignment, the optical fiber 122 is pressed from above with a holding plate 118 and fixed on the V-groove substrate 116 so as not to be displaced in the front-rear and left-right directions.

The end of the optical fiber 122 opposite to the side facing the laser diode array 114 is
It penetrates the side wall 110 a of the package 110 and projects outside the package 110. Therefore, laser light emitted from the laser diode array 114 can be easily extracted to the outside.

On the other hand, the high-frequency electric wiring substrate 102 is composed of five high-frequency electric wirings 104 (104a, 104b, 104c,
104d, 104e). In the present invention, the high-frequency electrical wiring 104
The ends of the two ends where the center-to-center distance with the adjacent high-frequency electric wiring 104 is small, that is, the end with the smaller pitch is referred to as the inner lead 104f, and the center of the opposite side of the inner lead 104f with the adjacent high-frequency electric wiring 104. The end portion having a larger distance, that is, the end having the larger pitch is referred to as an outer lead 104g. Then, each high-frequency electric wiring 104
Pitch of the inner lead 104f is 125 μm, for example.
Similarly, the pitch of the outer leads 104g of each high-frequency electric wiring 104 is, for example, 1250 μm. Therefore, the high-frequency electrical wirings 104 are arranged at a reduction rate of about 10 times.

The straight-line distance of each high-frequency electric wiring 104, that is, the straight-line distance is the length of the straight line assuming that a straight line is drawn from one end of the high-frequency electric wiring to the other end. (Distance), which is the shortest length (distance) of the high-frequency electrical wiring 104c located at the center and the next shortest high-frequency electrical wiring 104b located on both sides of the high-frequency electrical wiring 104c ,
For 104d, the lengths of these wirings (also referred to as wiring lengths) and the lengths of the high-frequency electric wirings 104a and 104e where the linear distance of the high-frequency electric wiring 104 is the longest are substantially equal to each other. The curved portions 124c, 124b, and 124d configured as described above are provided in the middle of each of the high-frequency electric wirings 104c, 104b, and 104d, respectively.

Regarding the number of the bending portions 124, two are provided for the high-frequency electric wiring 104c and two high-frequency electric wirings 104b and 104d on both sides thereof, regardless of the length of the wiring.

However, the high-frequency electrical wiring 104c has a shorter linear distance than the high-frequency electrical wirings 104b and 104d on both sides thereof.
The size of the curved portion 124c provided in 4c is larger than the size of the curved portions 124b and 124d of the high-frequency electrical wirings 104b and 104d.

Therefore, the high-frequency electric wiring 104 (10
4a, 104b, and 104c), the wiring lengths indicated by arrows beside the wirings can be made substantially equal. In this regard,
For example, each high-frequency electrical wiring 104a having a different linear distance,
The length of each of the high-frequency electrical wirings 104a, 104b, and 104c shown in FIG. 1 as indicated by an arrow is measured by using a means such as a CAD. Can be confirmed to be equal.

The high-frequency electric wirings 104d and 104d
Also in FIG. 4E, although the wiring length is not indicated by an arrow in the drawing, it is located at the target position with the high-frequency electric wirings 104a and 104b, and if the respective wiring lengths are measured using means such as CAD, other high-frequency electric wirings are obtained. It can be confirmed that it is substantially equal to the wiring.

Therefore, a predetermined high-frequency signal is supplied from a high-frequency power supply (not shown) via five connectors 120 provided on the side wall 110 a of the package 110 to the five connectors which are respectively electrically connected to the connectors 120. High-frequency electrical wiring 104 (104a, 104b, 104c, 10
4d, 104e), when input to the outer leads 104g in parallel, each high-frequency signal is transmitted to the inner lead 104f of each high-frequency electrical wiring 104.

At this time, each high-frequency electric wiring 104
Are substantially equal because the curved portion 124 is provided. Therefore, each high-frequency signal input in parallel can be transmitted to the inner lead 104 f of each high-frequency electric wiring 104 with substantially the same propagation time. In addition, since each of the curved portions 124 is formed by a curve, the high-frequency characteristics of the high-frequency signal are degraded, and the problem of crosstalk with the adjacent high-frequency electrical wiring is small.

Therefore, each bonding wire 108 is separated from the inner lead 104f of each high-frequency electric wiring 104.
The laser diodes (114a, 114b, 114c, 114d, 114) constituting the laser diode array 114 are generated by the high-frequency signals transmitted to the laser diode array 114 with almost no delay time via the
e) can each be driven separately. That is, the shift (variation) of the propagation time of the high-frequency signal in each high-frequency electric wiring 104 is reduced, and the problems of the high-frequency characteristics of the laser diode array 114 using the high-frequency signal and the transmission error are also reduced.

The shift in the propagation time of the high-frequency signal will be described in more detail with reference to FIG. That is, in FIG. 8, time (μsec.) Is plotted on the horizontal axis, and amplitude (relative value) is plotted on the vertical axis. Therefore, the pattern of the high-frequency signal can be represented by this figure.

FIG. 11 shows a high-frequency electric wiring having the shortest wiring length, for example, the high-frequency electric wiring 104c of FIG.
The case where the same high-frequency signal is input to the high-frequency electric wiring having the longest wiring length, for example, the high-frequency electric wiring 104a in FIG. 1 is shown. That is, a 1-bit (bit) high-frequency signal is represented by a waveform until the amplitude changes and returns to the original amplitude, and the required propagation time per 1-bit (bit) is t.
This is indicated by 1. Also, the difference in the propagation time of the high-frequency signal between the shortest high-frequency electrical wiring and the longest high-frequency electrical wiring is indicated by t2.

From this figure, it can be seen that in the high-frequency electric wiring having the shortest linear distance, the required propagation time per bit (in this case, when t1 is taken as a reference (100%)), , 1 bit (bi
It can be seen that the deviation time (delay time) of the required propagation time per t), in this case t2, is within 25%.

Therefore, if the propagation time is shifted within such a range, it can be said that the dispersion of the propagation time of the high-frequency signal between the high-frequency electrical wirings is small, and the high-frequency characteristics of the semiconductor element using this high-frequency signal are not deteriorated. The problem of transmission errors is also reduced.

Therefore, in the present invention, when it is said that the propagation time of the high-frequency signal of each high-frequency electrical wiring is substantially equal, the first reason is that deterioration of the high-frequency characteristics of the semiconductor element using the high-frequency signal or It refers to the propagation time of a high-frequency signal of each high-frequency electrical wiring when the problem of transmission error is small.
That is, in the high-frequency electrical wiring with the shortest linear distance,
Required propagation time per bit (bit) (100
%), The shift time of the required propagation time per bit in the high-frequency electrical wiring having the longest linear distance may exceed 25%.

However, when it is said that the propagation time of the high-frequency signal of each high-frequency electrical wiring is substantially equal, the second definition is
This means the case where the deviation of the propagation time of the high-frequency signal of each high-frequency electrical wiring shown in FIG. 8 is within 25%.

FIG. 2 is a view for explaining a modification of the high-frequency electric wiring board according to the first embodiment. The high-frequency electric wiring board 150 is disposed along the side wall of the package 180 of the laser diode array module, and the connector 160 and each high-frequency electric wiring 154
Electrically connected.

The high-frequency electric wiring substrate 150
Is similar to the high-frequency electric wiring substrate 102 shown in FIG. 1 in that a polyimide film is used for the electric insulating layer 156, but the curved portion 174 provided in the middle of the high-frequency electric wiring 154 has an arc shape. Is different. Hereinafter, points different from the high-frequency electric wiring substrate 102 shown in FIG. 1 will be mainly described, and the same points will be appropriately omitted.

Then, for example, the high-frequency electric wiring 154b
For example, from the connector 160 side, that is, from the outer lead 154g side of the high-frequency electric wiring 154b, the high-frequency electric wiring 154b is A, B, C, D,
Designed separately for E section.

That is, part A is the outer lead 154g.
And a part B is a curved part 174b, which is substantially constituted by an arc, and a part C is constituted again by a substantially straight line. The portion D is also a curved portion 174b, which is substantially constituted by the same arc as the portion B, and the portion E is also constituted by a substantially straight line. This corresponds to a part of the lead 154f. Therefore, the length of each part can be calculated from the length of the straight line and the arc, and as a result, the length of the high-frequency electrical wiring 154b can be calculated.

However, even in the case of the straight portion, the entire high-frequency electric wiring 154b may be partially deformed in relation to the joint of the curved portion 174 so that the high-frequency signal can be easily propagated. Also, as for the high-frequency electric wiring 154c, an arc smaller than the arc of the high-frequency electric wiring 154b is used, and the number of the curved portions 174c is four, which is different from the number of the curved portions 174b of the high-frequency electric wiring 154b. However, the high-frequency electrical wiring 154c is similar to the high-frequency electrical wiring 154b in that the high-frequency electrical wiring 154c also includes a straight line and a circular arc. Therefore, the length of the high-frequency electrical wiring 154c can also be calculated.

Therefore, to put it the other way around, the high-frequency electric wiring 15
4b and the length of the high-frequency electrical wiring 154c are calculated,
It can be designed to be substantially equal.

Therefore, the high-frequency electric wiring substrate 1
The length of each high-frequency electrical wiring 154 at 50 can be substantially equal. Therefore, by using the high-frequency electric wiring substrate 150, the variation in the propagation time of the high-frequency signal between the high-frequency electric wirings 154 can be reduced. Therefore, as already described in the description of the high-frequency electric wiring board according to the first embodiment, the problem of the high-frequency characteristics of a semiconductor element using this high-frequency signal, for example, the deterioration of the high-frequency characteristics of a laser diode array and the transmission error are reduced. be able to.

FIG. 3 is a view for explaining a high-frequency electric wiring board according to a second embodiment of the present invention. That is, when the laser diode array 214 is mounted using the high-frequency electrical wiring board 202 of the present invention, and the laser diode array module 200 is assembled, the lid of the package 210 of the module 200 is removed and viewed from above. 1 shows the configuration.

Hereinafter, in describing the high-frequency electric wiring substrate 202 of the second embodiment, the first high-frequency electric wiring substrate 202 shown in FIG.
The differences from the high-frequency electric wiring board 102 of the embodiment and the laser diode array module 100 using the same will be mainly described, and the same points will be appropriately omitted.

On the bottom 210b of the package 210, a high-frequency electric wiring board 202, a heat sink 212,
After the V-groove substrate 216 is arranged at a predetermined position, the V-groove substrate 216 is fixed using ordinary fixing means such as solder, respectively. This is the same as in the laser diode array module 100.

Also in this laser diode array module 200, the laser diode array 214 is fixed on the heat sink 212 without being different from the laser diode array module 100, and the V-groove substrate 216 has 5 optical fibers 2
22 is fixed by a holding plate 218, and the optical fiber 222 further
The laser beam emitted from 14 is configured to be extracted to the outside.

On the other hand, the high-frequency electric wiring substrate 202 has five linear high-frequency electric wirings 204 (2) having different lengths.
04a, 204b, 204c, 204d, 204e) are formed on the surface, and at this point, the high-frequency electric wiring substrate 10 of the first embodiment is not linear.
Different from 2.

The pitch of the inner leads 204f of the high-frequency electric wiring 204 is 125 μm,
The pitch of g is 1250 μm, respectively.
This is the same as the high-frequency electric wiring substrate 102 of the third embodiment.

The type of the material of the electric insulating layer 206 is changed according to the length of the high-frequency electric wiring 204 (sometimes referred to as the linear distance or the wiring length). This is different from the high-frequency electric wiring board 102 of the first embodiment using only the polyimide resin.

That is, the electric insulating layer 206 is formed along the high-frequency electric wiring 204 along the adjacent high-frequency electric wiring 20.
4 and each of the divided electric insulating layers 2
06 (206a, 206b, 206c, 206d, 20
6e), the relative dielectric constant of each high-frequency electrical wiring 204
(204a, 204b, 204c, 204d, 204
e) The shorter the length, the larger.

For example, if the wiring length is the longest (the reference length is L
And ) Are high frequency electrical wirings 204a and 204
e, the electric insulating layers 206a and 206e are made of a DuPont polyimide resin, Kapton (relative permittivity = 3.
50), and then the electrical insulating layers 206b and 20 corresponding to the high-frequency electrical wirings 204b and 204d having a long wiring length (0.84 L in design with respect to the reference length).
6d from Mitsubishi Plastics (Mitsubishi Pla)
products E002 (Relative permittivity = 5.1)
0), and the electric insulating layer 206c corresponding to the high-frequency electric wiring 204c having the shortest wiring length (designed to be 0.74L with respect to the reference length) is formed of a ceramic material Be.
ramicZ (Velamic Z) (Relative permittivity = 6.65)
It is made using

These materials are used in the Transmission Line Design Handbook (Transmi
session line design handbo
ok), Brian. C. Water (Brian. C .;
Waterl), manufactured by Artech,
Boston, PP. 435 to 441.

Therefore, the value obtained by multiplying the wiring length (reference length L) of each high-frequency electric wiring 204 by the square root of the relative dielectric constant of the corresponding electric insulating layer 206 is the high-frequency electric wiring 204a.
, 204e, and 1.87L, respectively, 1.89L for the high-frequency electrical wirings 204b and 204d, and 1.90L for the high-frequency electrical wiring 204c, and the high-frequency signal of each high-frequency electrical wiring 204 represented by the above equation (1). Is substantially equal.

Therefore, a predetermined high-frequency signal is supplied from a high-frequency power supply (not shown) via the five connectors 220 provided on the side wall 210a of the package 210 to the five high-frequency electric wires 204 (204a, 204b). , 204c,
204d, 204e), when input in parallel to the outer leads 204g, the respective high-frequency signals pass through the respective high-frequency electrical wirings 204, but have substantially equal propagation times, to the respective inner leads 204f with substantially equal propagation times, although the lengths are different. Convey. Then, the respective laser diodes constituting the laser diode array 214 are individually driven by the respective high frequency signals transmitted with little delay time from the inner leads 204f of the respective high frequency electric wires 204 via the respective bonding wires 208. be able to. That is, the variation in the propagation time of the high-frequency signal between the high-frequency electrical wirings 204 is small, and the problems of the high-frequency characteristics of the laser diode array 214 using the high-frequency signal and the transmission error are small.

FIG. 4 is a view for explaining a modification of the high-frequency electric wiring board according to the second embodiment of the present invention, and is a partially enlarged view of the high-frequency electric wiring board 252. However, the package 260 and the connector 270 of the module using the high-frequency electric wiring board 252 are also partially shown.

That is, in FIG. 4, as described above, the electric insulating layer 256 (256b, 256c, etc.) is formed along each high-frequency electric wiring 254 with the adjacent high-frequency electric wiring 254 (for example, 254b and 254c). Divided between Then, the divided electric insulating layer 256 (for example,
The relative permittivity of 256b and 256c) is increased as the length of each high-frequency electric wiring 254 (254b, 254c) becomes shorter.

Further, in the high-frequency electric wiring board 252, the electric insulating layer 256c corresponding to the shortest wiring length of the high-frequency electric wiring 254c is also divided into three parts (256) in the direction intersecting with the high-frequency electric wiring 254c.
r, 256s, 256t), and further divides the relative dielectric constant of at least one electrical insulating layer (256s) of each of the electrical insulating layers (256r, 256s, 256t) by the other electrical insulating layer (256r, 256r, 256t). 256t).

Therefore, the divided electric insulating layers 256
The relative dielectric constant of the electrical insulating layer 256c can be adjusted by finely changing the material constituting c. Therefore, each high-frequency electric wiring 254 (for example, 254b and 2
Despite the different length 54c), the propagation time of the high-frequency signal can be made more equal.

FIG. 5 is a view for explaining a high-frequency electric wiring board according to a third embodiment of the present invention. That is, in the case where the laser diode array 314 is mounted using the high-frequency electric wiring board 302 of the present invention and the laser diode array module 300 is assembled, the lid of the package 310 of the module 300 is removed and viewed from above. 1 shows the configuration. In the following description, the high-frequency electrical wiring board 302 of the third embodiment is different from the high-frequency electrical wiring board 102 of the first embodiment shown in FIG. 1 and the laser diode array module 100 using the same. The points will be mainly described, and the same points will be appropriately omitted.

On the bottom 310b of the package 310, a high-frequency electric wiring substrate 302, a heat sink 312,
After arranging the V-groove substrate 316 at a predetermined position, the V-groove substrate 316 is fixed using ordinary fixing means such as solder, respectively.
Same as 00.

In the laser diode array module 300, the laser diode array 314 is fixed on the heat sink 312 without being different from the laser diode array module 100. Optical fibers 3
22 is fixed by a holding plate 318, and the optical fiber 322 further controls the laser diode array 3.
The laser beam emitted from 14 is configured to be extracted to the outside.

On the other hand, the high-frequency electric wiring substrate 302 is composed of five linear high-frequency electric wirings 304 (3) having different lengths.
04a, 304b, 304c, 304d, 304e) are formed on the surface of the electrical insulating layer 306. Then, on both sides of the high-frequency electric wiring 304, the high-frequency electric wiring 304 forms a coplanar line with a ground.
The predetermined interval (gap) 330 (330a, 330b,
330c, 330d, and 330e), and a first ground 340 is provided substantially in parallel with each other, and a second ground 350 is provided entirely on the back side of the electrically insulating layer 306. And the first ground 3
The 40 and the second ground 350 are electrically connected using a through hole (not shown) or the like.

The high-frequency electric wiring board 3 of the third embodiment
02 is that the high-frequency electric wiring 304 constitutes a coplanar line with a ground in this way, and thus the high-frequency electric wiring substrates 102 and 20 of the first and second embodiments.
Different from 2.

The pitch of the inner leads 304f of the high-frequency electrical wiring 304 is 125 μm,
The pitch of g is 1250 μm, which is the same as that of the high-frequency electrical wiring substrates 102 and 202 of the first and second embodiments.

Then, according to the length of each high-frequency electric wiring 304 (also referred to as a linear distance or a wiring length).
For example, as the length of the high-frequency electrical wiring 304 becomes shorter,
The respective gaps (gaps) 330 with the first grounds 340 provided on both sides of each high-frequency electric wiring 304 are widened, or according to the length of each high-frequency electric wiring 304, that is, the high-frequency electric wiring The shorter the length of 304 is, the wider the width of each high-frequency electrical wiring 304 is.

Accordingly, the gap (gap) 330 with the first ground 340 provided on both sides of the high-frequency electric wiring 304 and the width of the high-frequency electric wiring 304 corresponding to the length of each high-frequency electric wiring 304 as described above. The effective relative permittivity corresponding to each of the high-frequency electrical wirings 304 can be easily changed by changing.

Therefore, by changing each propagation speed of a high-frequency signal in each high-frequency electric wiring having a different length, the effective relative permittivity corresponding to each high-frequency electric wiring 304 is changed.
Each can be substantially equal.

Each effective relative permittivity ε _eff n corresponding to each high-frequency electric wiring 304 is a value defined by the above equation (3), as described above.

This point will be described in more detail with reference to FIGS. 6 and 7. FIG. 6 shows a model of the high-frequency electric wiring board having the coplanar line with the ground shown in the figure as a model, and shows the distance (A) from the first ground provided on both sides of the high-frequency electric wiring. Assuming that they are equal, the value of the gap (mm) on one side is plotted on the horizontal axis, and the effective relative permittivity _eff (-) is _{plotted on the} vertical axis.

When the width (also referred to as line width) W of the high-frequency electric wiring is changed to 0.5, 1.0, 1.5, and 2.0 mm, the gap (m) in each line width is changed.
The relationship between m) and the effective relative permittivity ε _eff (-) is obtained by using the above equation (3). Each relationship,
This is indicated by four dotted lines.

The electric insulating layer in the model of the coplanar line with ground is assumed to be made of general glass epoxy, the relative dielectric constant ε is 4.5, and the thickness of the electric insulating layer is , 1.6 mm, and the thickness of each of the high-frequency electric wiring and the first ground were calculated as 0.1 mm.

In FIG. 6, since the relationship between the corresponding high-frequency electric wiring and the effective relative permittivity ε _eff is clear, the effective relative dielectric constant corresponding to the n-th high-frequency electric wiring from the left end in the above equation (3) is obtained. _Expressed as the rate ε _eff n,
_Expressed as an effective relative permittivity ε _eff .

As is apparent from FIG. 6, these four dotted lines are all about 0.5 to 5.0 m regardless of the line width.
Within the range of the gap of m, the curve shows a gently rising rightward curve and almost a straight line. If the gap is the same, the value of the effective relative permittivity decreases as the line width decreases.

For example, when the gap is 2.0 mm and the line width is 0.5 mm, an effective relative permittivity ε _eff (-) of about 3.14 is obtained. .0
mm, about 3.23, when the line width is 1.5 mm, about 3.32, and when the line width is 2.0 mm, about 3.3.
An effective relative permittivity of 8 is obtained.

Therefore, as described above, in the high-frequency electric wiring substrate 302 of the third embodiment, the shorter the length (linear distance) of each high-frequency electric wiring 304,
Either increase the gap 330 (gap) with the first ground 340 provided on both sides of each high-frequency electric wiring 304,
Alternatively, the length (linear distance) of each high-frequency electrical wiring 304
Is shorter, the width of each high-frequency electric wiring 304 is made wider, or furthermore, by combining both,
The values of the effective relative permittivity can be easily equalized. That is, the propagation time of the high-frequency signal in each of the high-frequency electrical wirings 304 having different lengths is calculated according to the above equation (2).
Each can be substantially equal.

In the high-frequency electric wiring board 304 of the third embodiment, which is a coplanar line with a ground, each high-frequency electric wiring 304 can not only make the propagation time of a high-frequency signal equal, but also make each high-frequency electric wiring Wiring 3
The characteristic impedance Zn corresponding to 04 can be made substantially equal.

This point will be described in more detail with reference to FIG. FIG. 7 is a model of the grounded coplanar line shown in FIG. 7, with the gap (A) between the first ground provided on both sides of the high-frequency electrical wiring as the gap (mm) on the horizontal axis and the vertical axis. Has a characteristic impedance Z
(Ω). Then, the width (also referred to as a line width) W of the high-frequency electric wiring is set to 0.5, 1.0, 1.5, 2..
The relationship between the gap (mm) and the characteristic impedance Z (Ω) at each line width when changed to 0 mm is as follows:
This is obtained using the above equation (4). Each relationship is shown by four solid lines.

The model of the coplanar line with ground was calculated using the same specifications as the coplanar line with ground shown in FIG. Further, in FIG. 7, since the relationship between the corresponding high-frequency electrical wiring and the characteristic impedance Z is clear, what is expressed as the characteristic impedance Zn corresponding to the n-th high-frequency electrical wiring from the left end in the above equation (4) is: Expressed as characteristic impedance Z.

As is apparent from FIG. 7, all four solid lines are approximately 0.5 to 1.0 m regardless of the line width.
m, the curve rises sharply to the right in the range of a gap of about 1.0 to 2.0 mm.
The graph shows that a substantially flat straight line is obtained within a gap of 0 mm.

For the same gap, the value of the characteristic impedance Z (Ω) increases as the line width W decreases. For example, if the gap is 2.0 mm and the line width is 0.2 mm.
In the case of 5 mm, the characteristic impedance Z of about 105
(Ω) is obtained. Similarly, when the line width is 1.0 mm,
When the line width is about 82 and the line width is 1.5 mm, the characteristic impedance Z (Ω) is about 68, and when the line width is 2.0 mm, the characteristic impedance Z (Ω) is about 62.

From these characteristics, for example, in the high-frequency electric wiring board 304 of the third embodiment, each high-frequency electric wiring 304 which is a coplanar line with a ground corresponds to the high-frequency electric wiring 304a having the longest wiring length. When the value of the effective relative permittivity and the line width are determined, the value of the characteristic impedance Z (Ω) is uniquely determined.

Next, from the above equation (2), the value of the effective relative permittivity ε corresponding to the high-frequency electric wiring 304b having the next longer wiring length is determined so that the propagation time of the high-frequency signal becomes substantially equal.
_{Find eff} .

Then, while maintaining the effective relative permittivity ε _eff , the line width W and the gap of the high-frequency electric wiring 304b are changed, and the characteristic impedance Z (Ω) of the high-frequency electric wiring 304a is changed by a trial and error method. The values of the line width W and the gap of the high-frequency electric wiring 304b are determined so as to be close to the value or the value of the characteristic impedance Z (Ω).

Therefore, in each high-frequency electric wiring 304 which is a coplanar line with a ground of the high-frequency electric wiring substrate 302 of the third embodiment, not only the propagation time of the high-frequency signal can be made equal, but also the characteristic impedance The value of Zn can also be substantially equal or close, and high frequency signal (power) can be effectively used by eliminating or reducing reflection of high frequency signal (power).

FIG. 9 is a partially enlarged view of the high-frequency electric wiring board for describing the high-frequency electric wiring board according to the fourth embodiment of the present invention. That is, the configuration when a part of the high-frequency electric wiring substrate 402 of the present invention is viewed from the cross-sectional direction is shown. The high-frequency electric wiring 404, the first ground 440 provided in parallel on both sides of the high-frequency electric wiring, and the electric insulating layer 406
Each is hatched to indicate that it is a cross section.

The width of the high-frequency electric wiring 404 is α, the gap 430 between the high-frequency electric wiring 404 and the first ground 440 on one side is γ, and the width α of the high-frequency electric wiring 404 is on both sides. The value obtained by adding the value (γ) of the interval (gap) 430 to the first ground 440 provided in parallel is β (α + γ + γ), the thickness of the high-frequency electrical wiring 404 is t, and the thickness of the electrical insulating layer 406 is Is indicated by h, and the relative dielectric constant of the electrically insulating layer 406 is indicated by ε _r .

Since the fourth embodiment is a modification of the third embodiment, the following description of the high-frequency electric wiring substrate 402 of the fourth embodiment will be made with reference to FIG. -Frequency electric wiring substrate 302 of the embodiment of the present invention and laser diode array module 300 using the same
The following description focuses on points that are different from the above, and omits the same points as appropriate.

That is, in the high-frequency electric wiring substrate 402 of the fourth embodiment, the high-frequency electric wiring substrate 302 of the third embodiment shown in FIG.
6, the second ground 350 is provided entirely on the rear side, but the second ground 350 is not provided. Therefore, the other structure is substantially the same as the high-frequency electric wiring board 302 of the third embodiment, and the high-frequency electric wiring board 40 of the fourth embodiment.
2, although not shown, according to the length of each high-frequency electrical wiring 404 (sometimes referred to as a linear distance or a wiring length), that is, the shorter the length of the high-frequency electrical wiring 404 is, , Gap (gap) with first ground 440 provided on both sides of each high-frequency electric wiring 404
430 is widened.

In addition, the width of each high-frequency electric wiring 404 is made larger in accordance with the length of each high-frequency electric wiring 404, that is, the shorter the high-frequency electric wiring 404 is.

Accordingly, in the high-frequency electric wiring substrate 402 of the fourth embodiment, each high-frequency electric wiring 4
A gap (gap) with the first ground 440 provided on both sides of the high-frequency electrical wiring 404 corresponding to the length of the wire 04
By changing the width of 430 or the high-frequency electric wiring 404, each effective relative permittivity ε _eff n can be easily changed.

Although not shown, the high-frequency electrical wiring board 404 of the fourth embodiment also has the same tendency as the high-frequency electrical wiring board of the third embodiment shown in FIG. And the first ground 44 on both sides
It has been confirmed that a graph showing the relationship between the gap (gap) to 0 and the effective relative permittivity _eff corresponding to the high-frequency electrical wiring can be obtained. Therefore, the respective propagation speeds of the high-frequency signals in the respective high-frequency electric wirings 404 having different lengths can be made substantially equal.

Each effective relative permittivity ε _eff n corresponding to each high-frequency electric wiring 404 is a value defined by the above equation (5) as described above, and similarly, K (k ′) /
K (k) means the reciprocal of the one defined in equation (5).

Although not shown, the high-frequency electric wiring board 402 of the fourth embodiment also has a high-frequency electric wiring substrate similar to the high-frequency electric wiring board of the third embodiment shown in FIG. Electrical wiring 404 and first on both sides
It has been confirmed that a diagram showing the relationship between the gap (gap) with the ground 440 and the characteristic impedance Z corresponding to each high-frequency electrical wiring can be obtained.

Therefore, in each high-frequency electric wiring 404 which is a coplanar line of the high-frequency electric wiring substrate 402 of the fourth embodiment, not only the propagation time of the high-frequency signal can be made equal, but also the characteristic impedance Zn The values can also be substantially equal or close. Therefore, by using the high-frequency electric wiring substrate 402 of the fourth embodiment, the reflection of the high-frequency signal (power) can be eliminated, and the high-frequency signal (power) can be used effectively.

As described above, with reference to FIGS. 1 to 9, high-frequency electric wiring substrates according to the first, second, third, and fourth embodiments of the present invention, and laser diodes as semiconductor elements using them. The embodiment of the laser diode array module in which the array is mounted and assembled is described.

However, the high-frequency electric wiring board of the present invention is not limited to the first, second, third and fourth embodiments, and each embodiment alone. For example, the first and second embodiments It is also preferable to combine the embodiments.

In other words, in a high-frequency electric wiring substrate configured to include at least an electric insulating layer and a plurality of high-frequency electric wirings for increasing or decreasing the pitch of the high-frequency electric wiring, each of the plurality of high-frequency electric wirings At least one curved portion is provided in the middle of the high-frequency electric wiring so that the lengths along the high-frequency electric wiring are substantially equal to each other, and the electric insulating layer is divided between adjacent high-frequency electric wirings along each high-frequency electric wiring. And, the relative dielectric constant of the divided electrical insulation layer, one end of the high-frequency electrical wiring,
It is also possible to increase as the distance (linear distance) connecting the other ends linearly decreases.

By configuring the high-frequency electric wiring substrate in this way, the variation in the propagation time (propagation speed) of the high-frequency signal between the high-frequency electric wirings can be further reduced. Similarly, the first and third embodiments, the first and fourth embodiments, the second and third embodiments,
Further, the first, second, and third, or first,
It is also preferable that the second and fourth embodiments are combined to form a high-frequency electric wiring substrate.

[0167]

According to the high-frequency electric wiring substrate of the present invention, there is provided a high-frequency electric wiring substrate configured to include at least an electric insulating layer and a plurality of high-frequency electric wirings for increasing or decreasing the pitch of the high-frequency electric wiring. At least one curved portion is provided in the middle of the high-frequency electric wiring so that the lengths of the plurality of high-frequency electric wirings are substantially equal to each other (first embodiment), or The electric insulating layer is divided along the high-frequency electric wiring between the high-frequency electric wirings so that the signal propagation speeds are substantially equal to each other, and the relative permittivity of the divided electric insulating layer is set to the high-frequency electric wiring. Is shorter (the second embodiment), or the high-frequency electric wiring is configured so that the high-frequency electric wiring forms a coplanar line with a ground. A first ground is provided on both sides of the high-frequency electrical wiring in parallel with the high-frequency electrical wiring, and a second ground is provided on the back surface of the electrical insulating layer. The distance between the high-frequency electrical wiring and the first ground is increased or the width of the high-frequency electrical wiring is increased as the straight-line distance of the high-frequency electrical wiring is shorter so as to be equal to each other.
Embodiment) Alternatively, a first ground is provided on both sides of the high-frequency electric wiring in parallel with the high-frequency electric wiring so that the high-frequency electric wiring constitutes a coplanar line, and a high-frequency signal in a plurality of high-frequency electric wirings is provided. The propagation time of
The distance between the high-frequency electrical wiring and the first ground is increased or the width of the high-frequency electrical wiring is increased as the linear distance between the high-frequency electrical wirings is shortened so that they are substantially equal (fourth embodiment). Form) reduces the variation in the propagation time of the high-frequency signal between the high-frequency electric wirings, prevents the deterioration of the high-frequency characteristics of the semiconductor element using the high-frequency signal, and reduces the problem of the transmission error. Can now be offered.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a high-frequency electric wiring substrate according to a first embodiment.

FIG. 2 is a view for explaining a high-frequency electric wiring substrate (modification) according to another first embodiment.

FIG. 3 is a diagram for explaining a high-frequency electric wiring substrate according to a second embodiment.

FIG. 4 is a view for explaining a high-frequency electric wiring substrate (modification) according to another second embodiment.

FIG. 5 is a diagram for explaining a high-frequency electric wiring substrate according to a third embodiment.

FIG. 6 is a diagram illustrating a relationship between a gap and a width of a high-frequency electric wiring and an effective relative permittivity in a high-frequency electric wiring substrate according to a third embodiment.

FIG. 7 is a diagram showing a relationship between a characteristic impedance and a gap and a width of a high-frequency electric wiring in a high-frequency electric wiring substrate according to a third embodiment.

FIG. 8 is a diagram for explaining a shift in propagation time of a high-frequency signal of each high-frequency electric wiring in the high-frequency electric wiring substrate.

FIG. 9 is a diagram for explaining a high-frequency electric wiring substrate according to a fourth embodiment.

FIG. 10 is a view for explaining a conventional high-frequency wiring board with bumps.

FIG. 11 is a view for explaining another conventional high-frequency electric wiring substrate.

[Explanation of symbols]

28: Bump 30: Ground 32: Ground post 50, 100, 200, 300: Laser diode array module 12, 52, 102, 150, 202, 252, 30
2, 402: high-frequency electric wiring board 14, 54, 104, 154, 204, 254, 30
4, 404: high-frequency electric wiring 14f, 54f, 104f, 154f, 204f, 30
4f: Inner lead 14g, 54g, 104g, 154g, 204g, 30
4g: Outer lead 16, 56, 106, 156, 206, 306, 40
6: electrical insulation layers 22, 62, 112, 212, 312: heat sinks 24, 64, 114, 214, 314: laser diode arrays 54a, 54b, 54c, 54d, 54e: high-frequency electrical wirings 58, 108, 208, 308 : Bonding wire 60, 110, 180, 210, 260, 310: package 60a, 110a, 210a, 310a: package side wall 60b, 110b, 210b, 310b: package bottom 66, 116, 216, 316: V-groove substrate 68 , 118, 218, 318: Holding plate 70, 120, 160, 220, 270, 320: Connector 72, 122, 222, 322: Optical fiber 104a, 104b, 104c, 104d, 104e:
Each high-frequency electric wiring 114a, 114b, 114c, 114d, 114e:
Each laser diode 122a, 122b, 122c, 122d, 122e:
Each optical fiber 124, 124b, 124c, 124d, 174, 17
4b, 174c: curved portions 154a, 154b, 154c, 154d, 154e:
Each high-frequency electric wiring 204a, 204b, 204c, 204d, 204e:
Each high-frequency electric wiring 206a, 206b, 206c, 206d, 206e:
Each electric insulating layer 254b, 254c: Each high-frequency electric wiring 256b, 256c, 256r, 256s, 256t:
Each electrical insulating layer 304a, 304b, 304c, 304d, 304e:
Each high-frequency electric wiring 330, 430: interval (gap) 340, 440: first ground 350: second ground

Claims (18)

[Claims] 1. A high-frequency electric wiring board for enlarging or reducing a pitch of a high-frequency electric wiring, comprising at least an electric insulating layer and a plurality of high-frequency electric wirings. A high-frequency electric wiring board, wherein at least one curved portion is provided in the middle of the high-frequency electric wiring so that the lengths along the wiring are substantially equal. 2. The high-frequency electric wiring board according to claim 1, wherein the curved portion is formed by a curved line. 3. The high-frequency electric wiring board according to claim 1, wherein the curved portion is constituted by a circle (arc), an elliptic curve, or a spline curve. Substrate. 4. A high-frequency electric wiring board configured to include at least an electric insulating layer and a plurality of high-frequency electric wirings for enlarging or reducing a pitch of the high-frequency electric wirings. The electric insulating layer is divided between the adjacent high-frequency electric wirings along the high-frequency electric wiring so that the times are substantially equal to each other, and the relative permittivity of the divided electric insulating layers is Is increased as the distance (linear distance) between one end of the high-frequency electric wiring and the other end linearly is shorter (linear distance). 5. The high-frequency electric wiring board according to claim 4, wherein the length of the high-frequency electric wiring is Ln, and the relative dielectric constant of an electric insulating layer corresponding to the high-frequency electric wiring is εn. A high-frequency electric wiring board, wherein a propagation time Tn of a high-frequency signal in each high-frequency electric wiring represented by the formula (1) is substantially equal to each other. (Equation 1) (Where c represents the speed of light in vacuum (about 3 × 10 ⁸ m / s), and the suffix n of each symbol represents the n-th high-frequency electrical wiring from the left end of each high-frequency electrical wiring It means that it corresponds.) 6. The high-frequency electric wiring board according to claim 4, wherein the electric insulating layer is divided also in a direction intersecting with the corresponding high-frequency electric wiring, and each of the divided electric insulating layers is further divided. Wherein the relative dielectric constant of at least one of the electrical insulating layers is different from the relative dielectric constant of the other electrical insulating layers. 7. A high-frequency electric wiring board configured to include at least an electric insulating layer and a plurality of high-frequency electric wirings for increasing or decreasing a pitch of the high-frequency electric wiring, wherein the high-frequency electric wiring forms a coplanar line with a ground. In such a manner, on both sides of the high-frequency electrical wiring on the surface of the electrical insulating layer, a first
And a second ground is provided on the back surface of the electrical insulating layer. The high-frequency signal is transmitted through each of the high-frequency electrical wirings so that the propagation times of the high-frequency signals are substantially equal to each other. The distance between the high-frequency electrical wiring and the first ground is increased as the distance (linear distance) between one end of the electrical wiring and the other end linearly connected is reduced. substrate. 8. The high-frequency electric wiring board according to claim 7, wherein the propagation times of the high-frequency signals in the plurality of high-frequency electric wirings are substantially equal to each other.
A high-frequency electric wiring substrate, wherein the shorter the straight-line distance of the high-frequency electric wiring, the wider the high-frequency electric wiring. 9. The high-frequency electric wiring board according to claim 7, wherein the length of each high-frequency electric wiring is Ln, and the effective ratio corresponding to each high-frequency electric wiring is represented by the following equation (3). _Assuming that the dielectric constant is ε _eff n, the propagation times Tn of the high-frequency signals in each high-frequency electric wiring represented by the following equation (2) are substantially equal to each other. substrate. (Equation 2) (Where c represents the speed of light in vacuum (about 3 × 10 ⁸ m / s), and the suffix n of each symbol represents the n-th high-frequency electrical wiring from the left end of each high-frequency electrical wiring It means that it corresponds to.) (Where a is the width of the high-frequency electric wiring (μm), b is the value of a plus the distance between the high-frequency electric wiring and the first ground on both sides (μm), and d is the value of b. A value (μm) obtained by adding the widths of the first grounds on both sides of the high-frequency electric wiring, h denotes the thickness of the electric insulating layer (μm), t denotes the thickness (μm) of the high-frequency electric wiring, and , The subscript n of the effective relative permittivity ε _eff n means that it corresponds to the n-th high-frequency electric wiring from the left end among the high-frequency electric wirings.) 10. The high-frequency electric wiring board according to claim 7, wherein the effective relative permittivity _eff n corresponding to each high-frequency electric wiring is 2.0 to 12.
A high-frequency electric wiring board, wherein the value is within a range of 0 (-). 11. The high-frequency electric wiring board according to claim 7, wherein the characteristic impedance Zn of each high-frequency electric wiring represented by the following formula (4) is 20:
A high-frequency electrical wiring substrate, wherein the value is within a range of 120 to 120 (Ω). (Equation 4) (Where η ₀ denotes the wave impedance in vacuum, ie, 377 (Ω), and a, b, t, and ε respectively.
_eff n, K (k ₁ ) / K (k ₁ ′), K (k ₂ ) / K
The value of (k ₂ ′) is as defined in equation (3), and the suffix n of each symbol corresponds to the n-th high-frequency electrical wiring from the left end of each high-frequency electrical wiring Means you are. ) 12. The high-frequency electric wiring board according to claim 11, wherein the characteristic impedance Zn in each of the high-frequency electric wirings is set to a value substantially equal to a value within a range of 10 to 100 (Ω). Characteristic high-frequency electrical wiring board. 13. A high-frequency electric wiring board configured to include at least an electric insulating layer and a plurality of high-frequency electric wirings for increasing or decreasing a pitch of the high-frequency electric wirings, wherein the high-frequency electric wirings form a coplanar line. To
On both sides of the high-frequency electrical wiring on the surface of the electrical insulating layer, first grounds are respectively provided in parallel with the high-frequency electrical wiring, and the propagation time of the high-frequency signal in each high-frequency electrical wiring is substantially each The distance between the high-frequency electric wiring and the first ground is increased as the distance (linear distance) between one end of the high-frequency electric wiring and the other end is linearly shorter so as to be equal. A high-frequency electrical wiring substrate characterized by the following. 14. The high-frequency electrical wiring board according to claim 13, wherein the linear distance of the high-frequency electrical wiring is short so that the propagation time of a high-frequency signal in each high-frequency electrical wiring is substantially equal. A high-frequency electric wiring board, wherein the width of the high-frequency electric wiring is increased. 15. The high-frequency electric wiring board according to claim 13, wherein the length of each high-frequency electric wiring is L.
n, and the effective relative permittivity corresponding to each high-frequency electrical wiring expressed by the following equation (5) is ε _eff n, the following equation (2)
Wherein the propagation times Tn of the high-frequency signals in the respective high-frequency electrical wirings are substantially equal to each other. (Equation 5) (Where c represents the speed of light in vacuum (about 3 × 10 ⁸ m / s), and the suffix n of each symbol represents the n-th high-frequency electrical wiring from the left end of each high-frequency electrical wiring It means that it corresponds to.) (Where, α is the width (μm) of the high-frequency electric wiring, β is the value (μm) of the value of α plus the distance between the high-frequency electric wiring and the first grounds on both sides, and h is the value of the electric insulating layer. Thickness (μ
m), and the suffix n of the effective relative permittivity ε _eff n means that among the high-frequency electrical wirings, it corresponds to the n-th high-frequency electrical wiring from the left end. ) 16. The high-frequency electric wiring board according to claim 13, wherein the characteristic impedance Zn of each high-frequency electric wiring represented by the following formula (6) is:
A high-frequency electric wiring substrate, wherein the value is within a range of 10 to 100 (Ω). (Equation 7) ( _Where the value of ε _eff n is as defined in equation (5), and the value of K (k ′) / K (k) is the value defined in equation (5). It is a reciprocal, and the suffix n of each symbol means that it corresponds to the n-th high-frequency electric wiring from the left end among the high-frequency electric wirings.) 17. The high-frequency electric wiring board according to claim 16, wherein the characteristic impedance Zn of each high-frequency electric wiring is set to a substantially equal value within a range of 10 to 100 (Ω). For high-frequency electrical wiring. 18. The high-frequency electric wiring board according to claim 1, wherein a distance (linear distance) between one end of the high-frequency electric wiring and the other end is the shortest. Based on the required propagation time per bit (bit) in the high-frequency electrical wiring as a reference (100%), the shift time of the propagation time per bit (bit) in the high-frequency electrical wiring having the longest linear distance is high. , 2
A high-frequency electrical wiring substrate, wherein the value is within 5%.