JP2006165414A - Relay substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a relay substrate that is superior in high-frequency characteristics and suitable for miniaturization. <P>SOLUTION: Upper lands 25A are arranged so that a side face 25a of one upper land 25A faces a side face 25a of another upper land 25 on a substrate 21, and an facing area S and a distance d between both the side faces 25a, 25a are set at a predetermined size, thereby forming an electrostatic capacity Ca between both the side face 25a, 25a. In this way, since a composite electrostatic capacity C, formed by this electrostatic capacity Ca and an electrostatic capacity C1 of an adjacent connection means 22, can be adjusted, the characteristic impedance of a relay substrate 20 decided by an inductance L of each of a spiral contacts 30 can be made to match characteristic impedances of a signal source side and a load side, and high-frequency characteristics can be improved. Also, since impedance matching can be attained, without requiring another member, such as coil and capacitor, the relay substrate 20 can be miniaturized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a relay substrate that connects an electronic component such as a semiconductor and a substrate, or a relay substrate that connects substrates, and more particularly to a relay substrate that has excellent high frequency characteristics and is suitable for miniaturization.

  As a prior art related to the present invention, for example, an electronic connector described in Patent Document 1 below exists.

In the electronic connector 1 described in Patent Document 1, a signal terminal provided on the center side is surrounded by a ground terminal provided on the outer periphery thereof, and as a result, the ground terminal is provided. Since the signal terminal can be electromagnetically shielded, it is possible to block noise that is easily superimposed on the signal terminal.
JP 2004-241304 A

  However, the electronic connector described in the above embodiment functions as an electromagnetic shield, that is, prevents high-frequency noise generated outside from being superimposed on the signal line, or a high-frequency signal transmitted on the signal line as noise. Although it can be prevented from being emitted to the outside, it is not a configuration that takes into account even high-frequency characteristics due to impedance matching.

  In other words, the operating frequency of semiconductors such as CPUs will be further increased in the future, but at this time, the matching between the output impedance of the signal source, the impedance of the transmission line (cable, wiring pattern, etc.) and the impedance of the load is insufficient. If so, reflection occurs at the connection point between the signal source and the transmission line and the connection point between the transmission line and the load. When the signal is a single shot, the amplitude level of the signal is temporarily set by combining the traveling wave and the reflected wave. In the case of a continuous wave, the traveling wave and the reflected wave interfere at every point on the transmission line, and a standing wave with a different amplitude is created at each point on the transmission line. However, the electronic connector is not configured to cope with high frequency characteristics such as reflection.

  Usually, such a problem of reflection is dealt with by setting a predetermined specified value (for example, 50 [Ω]) so that each impedance becomes the specified value.

By the way, the transmission line is a distributed constant circuit, and the characteristic impedance Z ₀ is different from the output impedance of the signal source and the impedance of the load, and is determined by the shape and size of the distributed constant circuit. When the self-inductance per unit length (1 m) is L and the capacitance is C, the following formula 1 is obtained.

However, since the shape and dimensions of the wiring pattern (transmission line) on the board differ from board to board, it is complicated to set the characteristic impedance Z ₀ of the wiring pattern (transmission line) to the specified value for each board. There's a problem.

Further, by providing the capacitor (C) and coil (L) on a substrate, wherein it is considered that the characteristic impedance Z ₀ of the transmission line is set to the specified value, simply providing the coils and capacitors as a separate member There is a risk that the cost may increase due to an increase in the number of parts, or that it may be difficult to reduce the size of the board due to the arrangement space.

  The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a relay substrate having excellent high-frequency characteristics by matching impedances of transmission lines on the substrate.

  It is another object of the present invention to provide a relay board that can achieve impedance matching without providing a separate member and is suitable for miniaturization.

The present invention includes a substrate, a plurality of land portions arranged on the substrate, and a contact piece that spirally extends in a central direction on the inner peripheral side from a support portion provided on the outer peripheral side. A relay board having a spiral contact fixed to the land part,
The spiral contact is divided into a signal and a ground, and between a side surface of the land portion for fixing the spiral contact for signal and a side surface of the land portion for fixing the spiral contact for ground. Further, a first facing portion for forming a capacitance is provided.

  Further, a second facing portion that forms a capacitance is provided between a side surface of the support portion that supports the spiral contact for signal and a side surface of the support portion that supports the spiral contact for ground. Can be.

  Further, a concavo-convex portion is formed on a side surface forming the first opposing portion and / or the second opposing portion, and a concave portion formed on one side surface facing each other is formed on the other side surface. It is also possible to arrange so that the projected portions are opposed to each other.

For example, a through hole is formed in the substrate, and the land portion is formed in a peripheral portion of the through hole.
Furthermore, the spiral contactor is provided on both front and back surfaces of the substrate.

  The land portion provided on the front surface side of the substrate and the land portion provided on the back side of the substrate may be conductively connected via a conductive portion provided on the inner surface of the through hole. .

  In the above, the characteristic impedance formed by the inductance component of the spiral contactor and the capacitance of the first facing portion and / or the second facing portion, and the impedance on the signal source side and the impedance on the load side Those in which matching is achieved are preferable.

  In the relay board of the present invention, the characteristic impedance formed by the electrostatic capacitance C formed in the first facing portion and / or the second facing portion and the L component originally included in the spiral contactor is connected to the relay substrate. Since the configuration matches the impedance of the signal source connected to the substrate and the load, the problem of reflection can be solved and a relay substrate excellent in high frequency characteristics can be obtained.

  In addition, since a dedicated coil or capacitor for impedance matching is not required, the relay board can be reduced in size, and an increase in the number of components and an increase in cost can be suppressed.

  FIG. 1 is a perspective view showing a connection device constituting a part of a semiconductor device inspection system as an embodiment using a relay board of the present invention, and FIG. 2 is a cross-sectional view taken along line 2-2 of the connection device shown in FIG. FIG. 3, FIG. 3 is a perspective view partially showing a relay board as an embodiment of the present invention, FIG. 4 is an exploded perspective view of connection means showing a state where only the board is removed from the relay board of FIG. 3, and FIG. FIG. 6 is an equivalent circuit diagram when the relay board is connected. FIG. 7 is a plan view of the connecting means showing the first embodiment for adjusting the facing area, FIG. 8A is a plan view of the connecting means showing the second embodiment for adjusting the facing area, FIG. 8B is a side view thereof, FIG. 9 is a plan view of the connecting means showing a third embodiment for adjusting the facing area.

  A connecting device 10 shown in FIGS. 1 and 2 includes a base 11 and a lid 12 that is rotatably supported via a hinge 13 provided at one edge of the base 11. is doing. The base 11 and the lid body 12 are formed of an insulating resin material or the like, and a loading region 11A that is concave in the Z2 direction is formed at the center of the base 11. A relay substrate 20 on which the electronic component 1 such as a semiconductor device is mounted is provided in the loading area 11A. A pressure unit 12 a is provided inside the lid body 12. A coil spring (not shown) or the like is provided between the inside of the lid 12 and the pressurizing portion 12a, and the surface of the electronic component 1 mounted in the loading region 11A is Z2 as will be described later. It is possible to pressurize in the direction. A locked portion 14 is formed on the other edge of the base 11, and a lock portion 15 is formed on the corresponding lid 12.

  The connection device 10 is for inspecting, for example, the electronic component 1 in which a large number of external connection electrodes 1a are arranged on the connection surface 1A.

  The external connection electrodes 1a are, for example, arranged outside the connection surface 1A in two rows along the vertical and horizontal directions, or in the form of a matrix (also referred to as a grid or grid) on the entire connection surface 1A. For example, a pin-shaped electrode (PGA), a planar electrode formed in a thin plate shape (LGA), a spherical electrode (BGA), or the like. . The external connection electrode 1a of the electronic component 1 shown in FIG. 2 is a planar electrode (LGA).

  As shown in FIG. 2, a relay board 20 is provided in the loading area 11A. A plurality of connecting means 22 are disposed on the relay substrate 20 so as to face the external connection electrodes 1 a of the electronic component 1. In FIG. 2, each connecting means 22 is indicated by hatching.

  FIG. 3 shows three sets of connecting means 22A, 22B, and 22C among the plurality of connecting means 22. One connecting means 22 includes an upper land portion 25A, a lower land portion 25B, a conductive portion 25C, and spiral contacts 30 fixed to the upper and lower land portions 25A and 25B, as will be described later.

  The substrate 21 forming the relay substrate 20 may be a substrate formed of a hard material with low flexibility such as glass epoxy, or may be a highly flexible substrate such as polyimide. In any case, it is formed of a resin material having high insulating properties.

  2 and 5, the substrate 21 is provided with a plurality of through holes 23 corresponding to the plurality of external connection electrodes 1a provided on the connection surface 1A of the electronic component 1. Around the upper and lower edges of the through-hole 23, a square frame-shaped upper land portion 25A and lower land portion 25B as shown in FIGS. 3 and 4 are provided.

  A cylindrical conductive portion 25C is formed along the inner wall of the through hole 23 between the upper land portion 25A and the lower land portion 25B. The upper land portion 25A, the lower land portion 25B, and the conductive portion 25C are formed by copper plating or the like, and the upper land portion 25A and the lower land portion 25B are conductively connected via the conductive portion 25C.

  On the other hand, spiral contacts 30 are respectively fixed to the upper surface (Z1 side surface) of the upper land portion 25A and the lower surface (Z2 side surface) of the lower land portion 25B. Each spiral contact 30 has a structure having a support portion 31 provided on the outer peripheral side and a contact piece 32 provided therein, and the support portion 31 includes the upper surface of the upper land portion 25A and the lower land portion 25B. Is fixed to the lower surface of the substrate via a conductive adhesive 24 or the like. The contact piece 32 is formed integrally with the support portion 31 and extends spirally or spirally from the winding start end 32a on the outer peripheral side toward the winding end 32b on the inner peripheral center side. The contact piece 32 is supported in a cantilevered manner with respect to the support portion 31 on the winding start end 32a side, and is elastically deformable in the Z1 and Z2 directions in the figure inside the conducting portion 25C. The contact piece 32 of the spiral contactor 30 may be a flat type as shown in FIGS. 3 and 5, but is preferably formed in a convex shape in advance as shown in FIGS. In particular, it is essential that the spiral contactor 30 on the lower land portion 25B side is formed so as to protrude in the Z2 direction shown in the drawing.

  The connection device 10 is provided on a mother board (mother board) 50. A plurality of conductive connection pads 51 formed corresponding to the plurality of through holes 23 are provided on the surface of the mother board 50. Each spiral contact 30 provided on the lower land portion 25 </ b> B side has a winding terminal end 32 b on the inner peripheral center side placed on each connection pad 51. The relay board 20 is supported on the mother board 50 by the elastic force of the spiral contact 30.

  As shown in FIG. 2, when the electronic component 1 is placed on the relay substrate 20 in the loading area 11 </ b> A, the lid body 12 is closed, and the locking between the locked portion 14 and the locking portion 15 is completed. The external connection electrode 1a of the electronic component 1 presses each spiral contact 30 provided on the upper side of the relay substrate 20 in the Z2 direction in the figure, so that each external connection electrode 1a and each spiral contact 30 are electrically connected. It is done.

  At the same time, since the whole relay board 20 is pressurized in the Z2 direction in the drawing, each spiral contact 30 provided on the lower side of the relay board 20 elastically presses each connection pad 51 of the mother board 50. Secured. That is, the external connection electrodes 1a of the electronic component 1 and the connection pads 51 of the mother board 50 are electrically connected.

  The lower land portion 25B side may be a convex pad that is formed of, for example, copper instead of the spiral contact 30 and protrudes in the Z2 direction shown in the figure. In this case, the lower end of the convex pad and the connection pad 51 can be secured with a conductive adhesive or the like to ensure electrical conduction therebetween.

  One end of a wiring pattern is connected to the connection pad 51, and the other end of the wiring pattern is drawn through the front surface or the back surface of the mother board 50, and an external circuit provided on the mother board 50. 40 (see FIG. 6).

Next, the configuration of the relay board 20 will be further described.
As shown in FIG. 3, in the relay board 20, both side surfaces 25a, 25a of the adjacent upper land portions 25A are first opposing portions 27 facing each other in a parallel state. The side surface 25a of one upper land portion 25A and the side surface 25a of the other upper land portion 25B are arranged to face each other with a predetermined distance d.

  Here, for example, in one adjacent connecting means 22A and the other connecting means 22B, the capacitance formed in the first facing portion 27 (between the facing side faces 25a) is Ca, other than the side face 25a. If the main capacitance formed between the adjacent conductive portions 25C is C1, the total capacitance C formed between the one connection means 22A and the other connection means 22B is the static capacitance. It is a combined capacity (C = Ca + C1) of the capacitance Ca and the main capacitance C1. Since the facing area S between the side surfaces 25a forming the first facing portion 27 is smaller than the facing area between the adjacent conducting portions 25C, the main static between the electrostatic capacitance Ca and the conducting portion 25C. The capacitance C1 has a relationship of C1 >> Ca. The above relationship is the same between other connection means, for example, between the connection means 22B and the connection means 22C.

  On the other hand, since the contact piece 32 of the spiral contact 30 is formed in a spiral shape, it has a predetermined inductance component (L component).

  Here, of the three connecting means 22A, 22B, and 22C shown in FIG. 3, the connecting means 22B located in the center is used for signals, and the connecting means 22A and 22C located on both sides thereof are used for ground (grounding). When arranged by connecting to a load, an equivalent circuit as shown in FIG. 6 can be obtained.

In FIG. 6, Vs is the signal source, Zs is the impedance of the signal source Vs, the _{Z L} is the impedance of the load. As shown in FIG. 6, the relay substrate 20 corresponds to a transmission line that connects the electronic component 1 corresponding to a load and an external circuit 40 having a signal source Vs, and the characteristic impedance Z ₀ is expressed by the above _{equation (} 1). Then, in the equivalent circuit shown in FIG. 6, each impedance Zs, is kept such that the following relation shown in Equation 2 (impedance matching) holds between the Z _0, Z _L.

上記数２を変形すると、設計上の総合静電容量Ｃは以下の数３で表すことができる。

When the above formula 2 is modified, the designed total capacitance C can be expressed by the following formula 3.

Further, when the distance between the side surfaces 25a is d, the height dimension is h, the length dimension of the side surface 25a is W, the vacuum dielectric constant is ε ₀ , and the relative dielectric constant of air is εr, the first facing portion 27 The electrostatic capacitance Ca is given by the following formula 4.

  Here, as described above, the capacitance Ca constituting the total capacitance C and the main capacitance C1 between the conductive portions 25C are in a relationship of C1 >> Ca. And most of the designed total capacitance C is formed by the main capacitance C1 between the conducting portions 25C, and the capacitance Ca is a small amount that compensates for the shortage of the capacitance C1. It exists as a capacitance for adjustment.

  That is, by setting the height dimension h forming the facing area S between the side faces 25a forming the first facing portion 27 and the length dimension W (S = h · W) of the side faces 25a to appropriate dimensions. The capacitance Ca can be finely adjusted, and the combined capacitance (Ca + C1) formed between the actual connection means 22 can be brought close to the designed total capacitance C (C≈Ca + C1). It becomes.

Therefore, the characteristic impedance Z ₀ of the transmission line (relay substrate 20) is set to a prescribed value, that is, the characteristic impedance Z ₀ of the transmission line (relay substrate 20) is set to the impedance Zs of the signal source Vs and the impedance of the load. Since it can be approximated to Z _L (Z ₀ ≈Zs = Z _L ), the connection point aa (see FIG. 6) between the signal source Vs and the transmission line and the connection point bb between the transmission line and the load. It is possible to suppress the occurrence of reflection with respect to (see FIG. 6).

Therefore, when the electronic component 1 and the external circuit 40 on the mother board 50 side are connected via the relay substrate 20 and the electronic component 1 is driven at a high operating frequency of, for example, several hundred MHz or more, the transmission line side the impedance Zs of the external circuit 40 of the mother substrate 50, which corresponds to the characteristic impedance Z ₀ of the relay substrate 20 to a signal source Vs side corresponding, matching or, closer to impedance match the impedance Z _L of the electronic component 1 that corresponds to the load side As a result, the problem of signal reflection that easily occurs at the connection point between the external circuit 40 of the mother board 50 and the relay board 20 and the connection point between the relay board 20 and the electronic component 1 can be solved. it can. That is, the relay substrate 20 having excellent high frequency characteristics can be obtained.

  As can be seen from Equation 4, the value of the fine adjustment capacitance Ca can be adjusted by changing the facing area S or the distance d between the side surfaces 25a and 25a.

  Accordingly, when it is desired to set the designed total capacitance C to a large value, the distance d between both side surfaces 25a and 25a forming the first facing portion 27 is shortened, or between the both side surfaces 25a and 25a. It can be adjusted by increasing the facing area S so that the value of the fine adjustment capacitance Ca is increased.

  However, if the distance d is extremely shortened, the signal connection means 22B and the ground connection means 22A and 22C are likely to be short-circuited. There is a natural limit to increasing the capacitance Ca.

  Therefore, in the first embodiment shown in FIG. 7, the concave and convex portions are formed on both side surfaces 25 a and 25 a forming the first facing portion 27. That is, the one side surface 25a and the other side surface 25a are in a shape in which the convex portion of the other side surface 25a is opposed to the concave portion of the one side surface 25a while maintaining a relationship in which the one side surface 25a opposes in parallel through the distance d. . Thereby, the substantial facing area S formed between the both side surfaces 25a, 25a can be increased, and the fine adjustment capacitance Ca can be increased.

  Alternatively, as shown in FIG. 8 as a second embodiment, the support portion 31 of the spiral contact 30 is formed in a square frame shape, and a side surface 31a of one support portion 31 and a side surface 31a of the other support portion 31 are formed. By forming the second facing portion 37 in the facing portion, the substantial facing area S is increased by increasing the height dimension h between the one connecting means 22B and the other connecting means 22C. The capacitance Ca for fine adjustment may be increased.

  When it is desired to set the capacitance Ca for fine adjustment to a small value, for example, only one of the two connection means 22A and 22C for ground is used, or the distance d between both side surfaces 25a and 25a is increased. It is possible to cope with it. However, since the connecting means 22A, 22B, 22C and the like need to be arranged at positions corresponding to the external connection electrodes 1a, there is a limit to the distance separating the distance d between the side surfaces 25a, 25a.

  Therefore, for example, as shown in FIG. 9 as a third embodiment, when one side of the upper land portion 25A is formed on the circular side surfaces 25b, 25b, the substantial facing area S can be reduced, and the first The fine adjustment capacitance Ca between the first facing portion 27 and the second facing portion 37 can be reduced.

As described above, in the present invention, the capacitance formed on the side surface of the spiral contactor elastically contacting the external connection electrode 1a of the electronic component 1 or the side surface of the support portion 31 to which the spiral contactor is fixed. By using Ca for fine adjustment, it is formed by the total capacitance C formed between the connecting means 22 including this fine adjustment capacitance Ca and the L component that the spiral contact originally has. to become a characteristic impedance Z _0, which is be able to match (matched) to the signal source Vs and load impedances Zs and Z _L, be a relay substrate 20 having excellent high-frequency characteristics to solve reflection problems Is possible.

  Moreover, in the present invention, the use of the connection means 22A, 22B, and 22C for connecting to the external connection electrode 1a of the electronic component 1 makes it possible to eliminate the need for a dedicated coil or capacitor for impedance matching. It is not necessary to secure a dedicated space for mounting the coil and the capacitor on the relay board 20. Therefore, the relay board 20 can be reduced in size, and an increase in the number of parts and an increase in cost can be suppressed.

  In the above embodiment, the relay board 20 is described as a member for connecting the electronic component 1 such as a semiconductor and the mother board 50 having the external circuit 40. However, the relay board 20 of the present invention is not limited to this. The present invention is not limited to this, and the boards may be directly connected to each other, or may be provided in a planar connector for indirectly connecting the boards.

  Moreover, the structure which has only any one may be sufficient as a said 1st opposing part and a 2nd opposing part, and the structure which has both may be sufficient.

The perspective view which shows the connection apparatus which comprises a part of test | inspection system of a semiconductor device as embodiment using the relay substrate of this invention, Sectional drawing in the 2-2 line of the connection apparatus shown in FIG. The perspective view which shows the relay board | substrate as embodiment of this invention partially, FIG. 4 is an exploded perspective view of connection means showing a state where only the board is removed from the relay board of FIG. A partial cross-sectional view of a relay board showing an enlarged connection means, Equivalent circuit diagram when connecting the relay board, The top view of the connection means which shows 1st Example which adjusts an opposing area, A is a plan view of connection means showing a second embodiment for adjusting the facing area, B is a side view thereof, The top view of the connection means which shows the 3rd Example which adjusts an opposing area,

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electronic component 1a External connection electrode 10 Connection apparatus 11 Base 11A Loading area 12 Lid 20 Relay board 22, 22A, 22B, 22C Connection means 23 Through hole 25A Upper land part 25B Lower land part 25C Conductive part 25a, 25b Side surface 27 First facing portion 30 Spiral contact 31 Support portion 32 Contact piece 37 Second facing portion 40 External circuit 50 Mother board (motherboard)
51 Connection pad Ca Capacitance formed between side surfaces (capacitance for fine adjustment)
C1 Capacitance formed between adjacent conductive parts (main capacitance)
C Total capacitance between connecting means (= Ca + C1)
L Inductance Z ₀ possessed by spiral contactor Z ₀ Characteristic impedance Zs of transmission path (relay substrate) Signal source impedance Z _L Load impedance

Claims (7)

A substrate, a plurality of land portions arranged on the substrate, and a contact piece that spirally extends from a support portion provided on the outer peripheral side toward the center on the inner peripheral side, and the support portion is fixed to the land portion. A relay board provided with a spiral contact,
The spiral contact is divided into a signal and a ground, and between a side surface of the land portion for fixing the spiral contact for signal and a side surface of the land portion for fixing the spiral contact for ground. The relay board is provided with a first facing portion for forming a capacitance.   A second opposing portion that forms a capacitance is provided between a side surface of the support portion that supports the spiral contact for signal and a side surface of the support portion that supports the spiral contact for ground. Item 8. The relay board according to Item 1.   An uneven portion is formed on the side surface forming the first facing portion and / or the second facing portion, and the protrusion formed on the other side surface is formed on the recessed portion formed on one side surface facing each other. The relay board according to claim 1, wherein the relay boards are arranged so as to face each other.   The relay substrate according to any one of claims 1 to 3, wherein a through hole is formed in the substrate, and the land portion is formed at a peripheral portion of the through hole.   The relay substrate according to claim 3, wherein the spiral contact is provided on both front and back surfaces of the substrate.   6. The land portion provided on the front surface side of the substrate and the land portion provided on the back side of the substrate are conductively connected via a conductive portion provided on the inner surface of the through hole. Relay board.   Matching is made between the characteristic impedance formed by the inductance component of the spiral contact and the capacitance of the first facing portion and / or the second facing portion, and the impedance on the signal source side and the impedance on the load side 7. The relay board according to claim 1, wherein:

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