JPH06163652A - Wiring board - Google Patents

Abstract

PURPOSE:To keep property impedance constant even if at least one hand between the shape of a transmission line and the sectional area is changed optionally. CONSTITUTION:Wiring resistance is reduced by bringing the transmission lines 1 arranged in radial shape close to the shape of a fan with a large area as far as possible, and earth patterns 2a are arranged along both sides of the transmission lines 1, and the interval (d) between the earth pattern 2a and the transmission lines 1 decreases accompanying the reduction of width dimension of the transmission lines 1, thus the property impedance in overall length of the transmission lines 1 is stabilized, and the reduction of transmission loss by the reduction of wiring resistance and the security of the conformity and uniformity of property impedance are reconciled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board, and more particularly to a technology effectively applied to a wiring expansion board for a probe used in a semiconductor device testing technique.

[0002]

2. Description of the Related Art For example, in a semiconductor device manufacturing process,
In some cases, a desired operation test or the like may be performed by pressing a fine probe (probe) from the outside against the terminals of a wafer-shaped or single semiconductor element to establish electrical continuity.

On the other hand, in a high-frequency signal transmission line or the like, the signal line width is made constant to match the characteristic impedance. Since this signal line width is a thin line width that matches the fine portion with the highest signal line density, resistance and loss are likely to increase. In particular, this effect is large in a radial signal pattern such as the above-described wiring expansion board of the probe.

Regarding conventional semiconductor device probe technology and the like, for example, the Industrial Research Institute Co., Ltd.
It is described in documents such as "Electronic Materials", November 18, 1983 issue, P195 to P198, issued on November 18, 1983.

[0005]

In a transmission line pattern having a dense and dense transmission line density such as a central portion and an outer peripheral portion such as a radial enlarged wiring pattern of a probe, the signal line is adjusted according to the density of the transmission line. The wiring resistance can be reduced by making the width as wide as possible. However, there is a problem that the characteristic impedance cannot be kept constant as it is.

Therefore, an object of the present invention is to provide a wiring board which can keep the characteristic impedance constant even if at least one of the shape and cross-sectional area of the transmission line is arbitrarily changed.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0008]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, the wiring board of the present invention is arranged along the transmission line and in the vicinity of the transmission line, and compensates the change in the characteristic impedance according to the change in at least one of the shape and the cross-sectional area of the transmission line. It consists of a ground pattern.

Further, according to the present invention, in the wiring board according to claim 1, the structure is such that the interval between the transmission line and the ground pattern is gradually reduced in the direction in which the cross-sectional area of the transmission line is gradually reduced.

Further, according to the present invention, in the wiring board according to the first or second aspect, the ground patterns are discontinuously arranged along the transmission line, and the interval between the adjacent ground patterns is changed.

Further, according to the present invention, the wiring board according to claim 1, 2 or 3 is used as a wiring expansion board which constitutes a probe card, and the transmission lines radially arranged have a fan having the largest possible area. It is shaped.

[0013]

According to the above-mentioned wiring board of the present invention, for example, the wiring resistance is lowered in accordance with the transmission line density,
The width of the transmission line is made as thick as possible, and the thickness of the wiring board is made thicker so that the target characteristic impedance is obtained, according to the maximum transmission line width and the material of the transmission line. As it is, the characteristic impedance is higher in the portion where the transmission line density is higher and the transmission line width is narrower. Therefore, the characteristic impedance is adjusted by appropriately adjoining the ground pattern.

As a result, the transmission line width can be widened and the resistance can be reduced in a place where the transmission line density is sparse while matching the characteristic impedance, so that the transmission loss is reduced and a high frequency signal is transmitted with high accuracy. It will be possible.

[0015]

First Embodiment A wiring board which is an embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view showing a part of the wiring board of this embodiment taken out, and FIG. 2 is a line II-- in FIG.
A sectional view of a portion indicated by II and FIG. 3 are plan views thereof.

The wiring board according to the present embodiment is configured as, for example, a wiring expansion board for a probe used in a semiconductor device testing technique.

That is, the inner ends of the plurality of radially arranged transmission lines 1 are pressed against the external connection terminals (not shown) provided on the semiconductor element 10, respectively.
a is attached. The transmission line 1 is sandwiched by grounding patterns 2 made of conductors arranged above and below via an insulator 3.

In this case, the transmission line 1 is formed in a substantially fan shape whose width dimension gradually increases from the inner end portion to which the probe 1a is connected to the outer end portion side to which a lead wire (not shown) is connected. And using the layout area as effectively as possible,
Wiring resistance is reduced by increasing the cross-sectional area.

Further, in the case of this embodiment, as illustrated in FIG. 2, the ground pattern 2a made of a conductor is arranged along both sides of each transmission line 1. The distance d between the ground pattern 2a and the transmission line 1 is set so as to gradually decrease as the width dimension of the transmission line 1 decreases.
The function of canceling the change in the characteristic impedance due to the change in the width dimension of (1) and making the characteristic impedance constant over the entire length of the transmission line 1 is maintained. The ground pattern 2a arranged between the adjacent transmission lines 1 also prevents the occurrence of crosstalk between the transmission lines 1.

With such a configuration, the wiring resistance of the transmission line 1 can be made as low as possible to reduce the transmission loss, and the characteristic impedance between the transmission line 1 and the probe 1a and the lead wire (not shown). It is possible to avoid deterioration of characteristics such as signal reflection due to mismatching of the signals, to transmit a high frequency signal with high accuracy, and to perform a desired test of the semiconductor element 10 smoothly.

Further, it is possible to easily and accurately cope with an increase in the number of external connection terminals in the semiconductor element 10 and an increase in operating frequency.

[0023]

[Embodiment 2] FIG. 4 is a schematic plan view showing a part of a wiring board according to another embodiment of the present invention, and FIG. 5 is a schematic view of a portion indicated by line V-V in FIG. FIG.

In the case of the second embodiment, the ground pattern 2b arranged in a layer different from the transmission line 1 with the insulator 3 interposed therebetween.
By changing the distance d1 of the transmission line 1 according to the change of the width dimension of the transmission line 1, the total length of the transmission line 1 whose width dimension changes,
It is different from the case of the first embodiment in that the characteristic impedance is made uniform to a target value.

As a result, also in the case of the second embodiment, the wiring resistance of the transmission line 1 can be made as low as possible to reduce the transmission loss, and at the same time, the transmission line 1, the probe 1a and a lead wire (not shown). It is possible to avoid deterioration of characteristics such as signal reflection due to mismatch of characteristic impedance between and, to transmit a high frequency signal with high accuracy, and to smoothly perform a desired test of the semiconductor element 10. Can be carried out.

Further, it is possible to easily and accurately cope with an increase in the number of external connection terminals in the semiconductor element 10 and an increase in operating frequency.

[0027]

Third Embodiment FIG. 6 is a schematic plan view showing a part of a wiring board according to still another embodiment of the present invention.
FIG. 7 is a schematic sectional view of a portion indicated by line VII-VII in FIG. 6.

In the case of the third embodiment, the ground patterns 2c arranged on both sides of the transmission line 1 are discontinuously divided in the lengthwise direction, and the distance d2 between adjacent ground patterns 2c is transmitted at that position. The width of the line 1 is changed according to the size.

Each of the divided ground patterns 2c is electrically connected to the lower or upper ground pattern 2 through the conductor 2d filled in the through hole 3a formed in the insulator 3.

Thus, as in the case of the first embodiment, the change in the characteristic impedance due to the change in the width dimension of the transmission line 1 is canceled by adjusting the size of the interval d2 between the adjacent ground patterns 2c, and the transmission line is changed. The characteristic impedance can be adjusted to a desired value over the entire length of 1.

As a result, also in the case of the third embodiment, the wiring resistance of the transmission line 1 can be made as low as possible to reduce the transmission loss, and at the same time, the transmission line 1, the probe 1a and a lead wire (not shown). It is possible to avoid deterioration of characteristics such as reflection of signals due to mismatch of characteristic impedance between them, to transmit high frequency signals with high accuracy, and to perform a desired test of the semiconductor element 10 smoothly. Can be carried out.

Further, it is possible to easily and accurately cope with an increase in the number of external connection terminals in the semiconductor element 10 and an increase in operating frequency.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the application of the wiring board is not limited to the wiring expansion board for the probe, but can be widely applied to a wiring board such as a package base on which a semiconductor element is mounted.

[0035]

The effects obtained by the representative one of the inventions disclosed in the present application will be briefly described as follows.

That is, according to the wiring board of the present invention, the characteristic impedance can be matched without making the transmission line width uniformly thin in accordance with the fine portion. Therefore, in a place where the transmission line density is low, the transmission line width can be widened to reduce the wiring resistance and highly accurate signal transmission becomes possible.

Further, even if the transmission line density is locally increased, the wiring resistance is increased only in that portion, and the influence on the whole is small, and the transmission line density can be locally increased. This can suppress an increase in the number of transmission line layers.

Further, the ground pattern existing between the adjacent transmission lines can reduce the crosstalk between the adjacent transmission lines and the ground pattern.

[Brief description of drawings]

FIG. 1 is a plan view showing a part of a wiring board according to an embodiment of the present invention.

FIG. 2 is a sectional view of a portion indicated by line II-II in FIG.

FIG. 3 is a plan view thereof.

FIG. 4 is a schematic plan view showing a part of a wiring board according to another embodiment of the present invention.

5 is a schematic cross-sectional view of a portion indicated by line V-V in FIG.

FIG. 6 is a schematic plan view showing a part of a wiring board according to still another embodiment of the present invention.

7 is a schematic cross-sectional view of a portion indicated by line VII-VII in FIG.

[Explanation of symbols]

 1 Transmission Line 1a Probe 2 Ground Pattern 2a Ground Pattern 2b Ground Pattern 2c Ground Pattern 2d Conductor 3 Insulator 3a Through Hole 10 Semiconductor Element d Interval d1 Interval d2 Interval

Claims (4)

[Claims] 1. A transmission line and a ground pattern which is arranged along the vicinity of the transmission line and which compensates for fluctuations in characteristic impedance according to changes in at least one of the shape and cross-sectional area of the transmission line. Characteristic wiring board. 2. The wiring board according to claim 1, wherein the distance between the transmission line and the ground pattern is gradually reduced in a direction in which the cross-sectional area of the transmission line is gradually reduced. 3. The wiring board according to claim 1, wherein the ground pattern is discontinuously arranged along the transmission line, and the interval between the adjacent ground patterns is changed. 4. A wiring board according to claim 1, wherein the wiring board is a wiring expansion board for a probe, and the transmission lines arranged in a radial pattern are formed into a fan shape having a large area as much as possible. .