JP2011249591A - Wiring board and probe card using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board in which a metal pin can be aligned easily with a conductor pad applied to an end face of a through-conductor and coming-off of the through-conductor is suppressed, and to provide a probe card using the same.SOLUTION: The wiring board comprises an insulation layer 1 having a through-conductor 2, and a conductor pad 3 applied from one principal surface of the insulation layer 1 to one end face of the through-conductor 2. An auxiliary insulation layer 4 is laminated on the one principal surface of the insulation layer 1. A guide hole 5 penetrating the auxiliary insulation layer 4 in the thickness direction thereof is formed so that the central part of the hole is located, in a plan view, at the outside of the outer periphery of the through-conductor 2 and the inside of the outer periphery of the conductor pad 3, so that a part of the conductor pad 3 is exposed in the guide hole 5. A metal pin P can be aligned with the conductor pad 3 by using the guide hole 5. Furthermore, coming-off of the through-conductor 2 can be suppressed because a force of the metal pin P is applied mostly to the insulation layer 1 side.

Description

  The present invention relates to a wiring board including an insulating layer having a through hole penetrating in the thickness direction, and a conductor pad deposited from one main surface of the insulating layer to an end face of the through conductor, and a probe card using the wiring board. In particular, the present invention relates to a wiring board and a probe card in which a metal pin for connection with a circuit conductor of a circuit board constituting a probe card is repeatedly pressed against a conductor pad.

  2. Description of the Related Art Conventionally, a wiring board used for mounting electronic components or the like has been provided with an insulating layer made of an insulating material such as a ceramic sintered body and a through conductor that penetrates the insulating layer in the thickness direction. Such a wiring board has, for example, a circuit conductor of the circuit board electrically connected to an end surface of the through conductor exposed on one main surface side of the insulating layer and a through conductor exposed on the other main surface side of the insulating layer. An electrode of an electronic component such as a semiconductor integrated circuit element or a probe for performing an electrical inspection of the electronic component is connected to the end face of the semiconductor device. And an electronic component is electrically connected with the circuit conductor of a circuit board via a penetration conductor, and transmission / reception of a signal, an electrical test | inspection with respect to an electronic component, etc. are performed.

  A through conductor is formed by filling a conductive material into a through hole formed by mechanical processing or laser processing in an insulating layer by a method such as vapor deposition, sputtering, plating, filling of conductor paste, and heating. Is formed.

  Electrical connection between the through conductor and the circuit conductor is made through a metal pin. For electrical connection between the metal pin and the through conductor, a conductor pad is attached from one main surface of the insulating layer to the end surface of the through conductor exposed on the one main surface side. For example, a metal pin that can be partially expanded and contracted is used. One end of the circuit pin is fixed at a predetermined position of the circuit conductor, and the other end is pressed against a conductor pad of the circuit board. The conductor pads and the through conductors are electrically connected.

  In this way, if the metal pin is pressed against the conductor pad without being bonded by a method such as brazing, it is electrically connected so that the through-conductor of the wiring board (and the electronic via the through-conductor). It is possible to easily assemble or replace a circuit board having a circuit conductor that is electrically connected to the electrode of the component. If the external electrical circuit board can be replaced, for example, after using a probe card for semiconductor element inspection, only the defective wiring board or probe is replaced and reassembled. Wiring boards and probes that are not used can be reused. Further, during assembly (positioning of the wiring board and the circuit board, etc.), even if there is an electrically poor connection due to misalignment or the like, readjustment is possible immediately.

  In recent years, in such wiring boards for probe cards and the like, miniaturization of through conductors and conductor pads formed in an insulating layer in accordance with the increase in the density of electronic components such as semiconductor elements (small area in plan view) As a result, the alignment of metal pins with respect to conductor pads is becoming difficult. For such a problem, another insulating layer having a through hole at a position corresponding to the conductor pad is arranged on one main surface side of the insulating layer on which the through conductor is formed, and the through hole of the other insulating layer is disposed. It has been proposed to guide the metal pin through the center of the conductor pad and press it.

JP 2007-27592 A

  However, in the above-described prior art wiring board, force (load) when pressing the metal pin against the conductor pad is repeatedly applied to the through conductor in the length direction of the through conductor through the conductor pad. For this reason, there is a problem in that a part or all of the conductor material constituting the through conductor filled in the through hole in the above method may escape from the through hole to the outside. In addition, when the metal pin is aligned with the conductor pad through the through hole, the metal pin is repeatedly pressed against a certain portion such as the central portion of the conductor pad, so that the through conductor is not pulled out by the force. It is likely to occur.

  The present invention has been completed in view of the above-described conventional problems, and an object of the present invention is to provide a circuit conductor having a through conductor formed in an insulating layer and a conductor pad attached to an end face of the through conductor. It is easy to align the metal pins for electrical connection with the conductor pads, etc., and even if the metal pins are repeatedly pressed against the conductor pads, the through conductors may come out of the insulating layer to the outside. An object of the present invention is to provide a wiring board in which this is effectively suppressed, and a probe card using the wiring board.

  The wiring board of the present invention includes an insulating layer having a through conductor penetrating in the thickness direction, and a conductor pad deposited from one main surface of the insulating layer to one end surface of the through conductor exposed on the one main surface side; The auxiliary insulating layer is laminated on one main surface of the insulating layer, and the central portion of the auxiliary insulating layer is outside the outer periphery of the through conductor in plan view, and the conductor A guide hole is formed inside the outer periphery of the pad and penetrates the auxiliary insulating layer in the thickness direction, and a part of the conductor pad is exposed in the guide hole. It is.

  Moreover, the wiring board of the present invention is characterized in that, in the above configuration, the conductor pad is provided with a convex portion whose side surface is located at the center of the guide hole in a plan view.

  The probe card of the present invention has a wiring board having any one of the above-described structures and a circuit conductor in which one end of a metal pin is joined, and is arranged in contact with the exposed main surface of the insulating layer of the wiring board. A circuit board in which the circuit conductor is electrically connected to the conductor pad by pressing the other end of the metal pin against the conductor pad, and the other main side opposite to the one main surface of the wiring board. And a probe pin electrically connected to the other end surface of the through conductor exposed on the surface side.

  According to the wiring board of the present invention, an insulating layer having a through conductor penetrating in the thickness direction and a conductor pad deposited from one main surface of the insulating layer to one end surface of the through conductor are provided. The auxiliary insulating layer is laminated on the surface, and the central portion of the auxiliary insulating layer is located outside the outer peripheral portion of the through conductor and inside the outer peripheral portion of the conductor pad in plan view. Since a guide hole penetrating through is formed and a part of the conductor pad is exposed in the guide hole, even if a metal pin for connection with a circuit conductor or the like is repeatedly pressed against the conductor pad, The pressing force mainly acts on one main surface of the insulating layer through the conductor pad. Therefore, the force that repeatedly acts on the through conductor in the length direction of the through conductor can be effectively reduced. Therefore, even if the metal pin is repeatedly pressed against the conductor pad, it is possible to provide a wiring board in which the through conductor is effectively prevented from coming out of the insulating layer.

  In addition, the metal pin that electrically connects the circuit conductor and the conductor pad can be easily and reliably guided to the exposed portion of the conductor pad through the guide hole of the auxiliary insulating layer and can be electrically connected.

  In the wiring board of the present invention, in the above configuration, when the conductor pad is provided with a convex portion whose side surface is located at the center portion of the guide hole in plan view, the side surface of the metal pin is convex of the conductor pad. By contacting the side surface of the portion, the connection area between the metal pin and the conductor pad can be increased. Therefore, the electrical connection between the metal pin and the conductor pad can be performed more easily and with low resistance.

  In addition, the probe card of the present invention has a wiring board having any one of the above-described structures and a circuit conductor in which one end of a metal pin is joined, and is disposed in contact with the exposed main surface of the insulating layer of the wiring board. A circuit board in which the circuit conductor is electrically connected to the conductor pad by pressing the other end of the metal pin against the conductor pad, and a through hole exposed on the other main surface side opposite to the one main surface of the wiring board Since the probe pin is electrically connected to the other end surface of the conductor, even if the metal pin is repeatedly pressed against the conductor pad of the wiring board, the force applied from the metal pin is mainly insulated via the conductor pad. Acts on one major surface of the layer. Therefore, the force that repeatedly acts on the through conductor in the length direction of the through conductor can be effectively reduced. Further, the metal pin for electrically connecting the external electric circuit and the conductor pad can be easily and surely guided to the conductor pad and electrically connected through the guide hole of the auxiliary insulating layer. Therefore, the electrical connection between the conductor pad and the circuit conductor via the metal pin is easy, and even if the metal pin is repeatedly pressed against the conductor pad, the through conductor may come out of the insulating layer to the outside. Therefore, it is possible to provide a probe card that can be used stably over a long period of time.

It is sectional drawing which shows an example of embodiment of the wiring board of this invention. It is a top view which shows the other example of embodiment of the wiring board of this invention. It is sectional drawing which shows an example of embodiment of the probe card of this invention. It is sectional drawing which shows the other example of embodiment of the wiring board of this invention, and a probe card. (A)-(c) is a top view (perspective view) which shows the other example of embodiment of the wiring board of this invention, and a probe card, respectively. It is sectional drawing which shows the other example of embodiment of the wiring board of this invention, and a probe card. It is sectional drawing which shows the other example of embodiment of the wiring board of this invention.

  The wiring board of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing an example of an embodiment of a wiring board according to the present invention. In FIG. 1, 1 is an insulating layer, 2 is a through conductor, 3 is a conductor pad, 4 is an auxiliary insulating layer, and 5 is a guide hole.

The wiring substrate is attached from one main surface (upper surface in the example shown in FIG. 1) of the insulating layer 1 having the through conductor 2 penetrating in the thickness direction to the end surface (one end surface) of the through conductor 2 on the one main surface side. The metal pin P is pressed against the conductive pad 3 through the guide hole 5 of the auxiliary insulating layer 4 and used. That is, the one main surface side and the other main surface (lower surface in the example shown in FIG. 1) side of the insulating layer 1 are electrically connected through the metal pin P and the through conductor 2. The one main surface side and the other main surface side of the insulating layer 1 are electrically connected via the metal pin P and the through conductor 2, whereby the wiring board is used for inspecting a semiconductor element that is an electronic component. It can be used for a probe card, an electronic component mounting board, and the like. In a probe card or an electronic component mounting substrate, an electronic component is disposed on the other main surface side of the insulating layer 1, and a circuit board or the like electrically connected to the electronic component is disposed on one main surface side.

  The insulating layer 1 is composed of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a glass ceramic sintered body, crystallized glass in which crystal components are precipitated in a glass base material, mica, or titanic acid. Ceramic materials such as ceramic materials (so-called machinable ceramics) made of sintered microcrystals such as aluminum and capable of precise machining that is almost equivalent to metal materials, soda glass, borosilicate glass, quartz glass, crystallization Glass materials such as glass, resin materials such as epoxy resin, polyphenylene sulfide resin, polyquinoline resin, polyphenylene ether resin, polyimide resin, polyamide imide resin, polyether ether ketone resin, aramid resin, and glass fiber or A composite material impregnated with silica filler, It is formed of a silicon. In the example shown in FIG. 1, only one insulating layer 1 is provided, but a plurality of such insulating layers 1 may be stacked one above the other. When a plurality of insulating layers (not shown) are stacked, it is necessary to connect the respective through conductors (not shown) vertically.

  If the insulating layer 1 constitutes a wiring board used for forming a probe card used for inspection of a semiconductor element which is an electronic component, for example, a substrate of the semiconductor element (a plurality of integrated circuit elements are arranged vertically and horizontally) The shape and size may be the same as the shape and size of the formed silicon wafer or the like. Moreover, the thickness of the insulating layer 1 should just be the thickness which can ensure the rigidity according to the use use as wiring boards, such as a probe card, for example, consists of an aluminum oxide sintered body, and is for the test | inspection of the said semiconductor element. If it is used as a probe card, the thickness may be about 1 mm to 5 mm.

  If the insulating layer 1 is made of, for example, an aluminum oxide sintered body, it can be manufactured as follows. That is, a ceramic green sheet is formed by forming a slurry prepared by adding and mixing an appropriate organic binder and organic solvent to raw material powders such as aluminum oxide and silicon oxide into a sheet shape by a sheet forming technique such as a doctor blade method or a lip coater method. After that, the ceramic green sheet can be made into an appropriate shape and size by cutting or punching and fired at a temperature of about 1300 to 1500 ° C.

  The insulating layer 1 has, for example, a square plate shape or a disk shape, and an auxiliary insulating layer 4 described later is laminated on the main surface side. The insulating layer 1 is mounted with an electronic component for mounting and electrical checking on the other main surface opposite to the one main surface (because the electronic component is electrically and mechanically connected to the wiring board to form an electronic device). It is used as a part for mounting or temporary mounting for performing an electrical check on an electronic component. Electronic components include semiconductor integrated circuit elements such as ICs and LSIs, semiconductor elements including optical semiconductor elements such as LEDs (light emitting diodes), PDs (photodiodes), and CCDs (charge coupled devices), surface acoustic wave elements, and crystal vibrations. Various electronic components such as a piezoelectric element such as a child, a capacitive element, a resistor, and a micromachine (so-called MEMS element) in which a minute electromechanical mechanism is formed on the surface of a semiconductor substrate can be given.

  The insulating layer 1 is formed with a through conductor 2 penetrating in the thickness direction. A conductor pad 3 is attached from one main surface of the insulating layer 1 to the end surface (one end surface) of the through conductor 2 exposed on the one main surface side. The through conductor 2 and the conductor pad 3 are for forming a conductive path for electrically connecting an electronic component mounted on the other main surface side of the insulating layer 1 to a circuit conductor or the like of a circuit board described later.

The through conductor 2 is formed by filling a metal material into a circular hole or an elliptical through hole (not shown) penetrating the insulating layer 1 in the thickness direction. Examples of the metal material forming the through conductor 2 include metal materials such as copper, silver, palladium, gold, platinum, aluminum, chromium, nickel, cobalt, titanium, tungsten, molybdenum, and manganese, or alloys of these metal materials. Can be mentioned.

  Through-holes previously formed in the insulating layer 1 by using a method such as a thin film method such as sputtering, vapor deposition, or plating, or a thick film method such as printing and heating a metal paste, for example. The through conductor 2 can be formed by filling the inside.

The through-hole can be formed in the insulating layer 1 by a method such as laser processing using a carbon dioxide (CO ₂ ) laser or ultraviolet laser, or mechanical drilling using drilling or blasting.

The conductor pad 3 is formed by depositing the same metal material as that forming the through conductor 2 from one main surface of the insulating layer 1 to one end face of the through conductor 2. The conductor pad 3 has a shape and dimensions so as to cover the end surface of the through conductor 2, and is attached in a pattern such as a circular shape, an elliptical shape, or a rectangular shape that is slightly larger than the end surface of the through conductor 2. If the through conductor 2 has a circular shape with a diameter of about 0.1 to 1.0 mm, the conductor pad 3 may have a circular shape or the like whose diameter is larger by about 0.05 to 0.5 mm than the end face of the through conductor 2.

  Specifically, such a conductor pad 3 includes an adhesive metal layer (not shown) made of chromium, molybdenum, titanium or the like on one main surface of the insulating layer 1 and copper or the like deposited thereon. A base conductor layer (not shown) composed of a metal thin film layer is first formed by an electroless plating method, a sputtering method, or the like, and thereafter, a portion that becomes a predetermined conductor pad 3 is covered using a photolithography method. After forming a resist pattern (not shown), an excess base conductor layer not covered with the resist pattern is removed by a chemical etching method or a dry etching method, and then the resist pattern is removed to obtain a predetermined pattern. Can be deposited.

  The auxiliary insulating layer 4 is for providing a guide hole 5 in the wiring board, and the guide hole 5 formed in the auxiliary insulating layer 4 has a metal pin P for electrically connecting the electronic component to the conductor pad 3. This is to guide the conductor pad 3 to easily and reliably connect the metal pin P to the conductor pad 3. Therefore, the auxiliary insulating layer 4 needs to be positioned and laminated on one main surface of the insulating layer 1 so that at least a part of the conductor pad 3 is exposed inside the guide hole 5. The auxiliary insulating layer 4 can be formed by the same method using the same material as that of the insulating layer 1, for example. The auxiliary insulating layer 4 may be set, for example, to have the same outer shape and dimensions as the outer shape and dimensions of the insulating layer 1.

  The metal pin P has a cylindrical shape, a square column shape, an elliptical column shape or the like having a diameter of about 0.3 to 0.5 mm. In the example shown in FIG. 1, the tip portion pressed against the conductor pad 3 is formed in a conical shape or the like.

  The metal pin P is formed by performing surface treatment such as Rh (rhodium) plating on a metal material such as beryllium-copper or iron-nickel alloy. If the metal pin P is made of beryllium-copper, for example, the raw material is subjected to metal processing such as rolling, cutting, etching, etc., processed into a predetermined shape and size, and then surface-treated by Rh plating. Have been made.

In the wiring board of the present invention, the guide hole 5 has a central portion located outside the outer peripheral portion of the through conductor 2 and inside the outer periphery of the conductor pad 3 in plan view, and penetrates the auxiliary insulating layer 4 in the thickness direction. Is formed. A part of the conductor pad 3 is exposed in the guide hole 5.

  Thus, since the center part of the guide hole 5 is located outside the outer peripheral part of the through conductor 2 in plan view, even if the metal pin P for external connection is repeatedly pressed against the conductor pad 3 The pressing force mainly acts on one main surface of the insulating layer 1 through the conductor pad 3. Therefore, the force that repeatedly acts on the through conductor 2 in the length direction of the through conductor 2 can be effectively reduced. Therefore, even if the metal pin P is repeatedly pressed against the conductor pad 3, it is possible to provide a wiring board in which the through conductor 2 is effectively prevented from coming out of the insulating layer 1.

  The force for pressing the metal pin P against the conductor pad 3 is, for example, about 0.39 N in the case of a probe card for semiconductor element inspection. ) Is not induced in the insulating layer 1 made of an aluminum oxide sintered body. In addition, in order to suppress mechanical destruction and early wear of the conductor pad 3 when such a force pressing the metal pin P is applied, the thickness of the conductor pad 3 should be set to about 3 μm or more. In view of the productivity and economics of the wiring board, it is more preferable that the thickness be in the range of about 1 to 10 μm.

The conductor pad 3 is, for example, a circular or elliptical shape slightly larger than a circle having a diameter of about 0.05 to 0.5 mm as described above. Among these, a metal pin having a diameter of about 0.3 to 0.5 mm as described above. For connection with P, about 1/3 to 1/2 of the whole, such as a fan shape with a central angle of about 60 to 90 degrees, may be exposed in the guide hole 5.

  When the guide hole 5 effectively suppresses the force that presses the metal pin P against the conductor pad 3 from acting on the through conductor 2, the entire metal pin P is outside the through conductor 2 in a plan view, that is, It is preferable that the insulating layer 1 be formed at a position that is in contact with the conductor pad 3 at a position overlapping one main surface. For example, when the tip of the metal pin P has a sharp shape such as a conical shape, the inner surface of the guide hole 5 is positioned on the outer periphery of the through conductor 2 in plan view (the center of the guide hole 5 is surely (Corresponding to the insulating layer 1).

  Note that, for example, as shown in FIG. 2, a plurality of such wiring boards may be arranged in rows and columns. By arranging a plurality of wiring boards vertically and horizontally, for example, inspection or the like can be performed corresponding to a larger semiconductor substrate. FIG. 2 is a plan view showing another example of the embodiment of the wiring board of the present invention. In FIG. 2, the same parts as those in FIG.

  Such a wiring board is used to form the above-described probe card, for example, as shown in FIG. FIG. 3 is a cross-sectional view showing an example of an embodiment of the probe card of the present invention, and the same parts as those in FIG. The probe card shown in FIG. 3 is manufactured using, for example, the wiring board shown in FIG.

In FIG. 3, 6 is a circuit board having a circuit conductor 7, and 8 is a probe pin. The circuit board having the above structure and the circuit conductor 7 which is disposed in contact with the exposed main surface of the auxiliary insulating layer 4 of the wiring board and to which one end of the metal pin P is joined are provided. A circuit board 6 disposed in contact with the exposed main surface and the other end of the metal pin P being pressed against the conductor pad 3 to electrically connect the circuit conductor 7 to the conductor pad 3; On the other hand, the probe card is basically constituted by probe pins 8 electrically connected to the other end face of the through conductor 2 exposed on the other main face side opposite to the main face. In the example shown in FIG. 3, a connection pad 9 is attached from the other main surface of the insulating layer 1 to the other end surface of the through conductor 2, and a probe pin 8 is joined to the connection pad 9 via a brazing material or the like. The pin 8 and the other end surface of the through conductor 2 are electrically connected.

  The circuit board 6 has a circuit conductor 7 formed on the surface of a resin substrate or the like for inspecting whether an integrated circuit of a semiconductor element which is an electronic component, for example, operates normally. If the wiring board is used for an electronic component mounting board other than the probe card, etc., an electronic device that exchanges electrical signals with the electronic parts for calculation, storage, etc., instead of the circuit board 6. An external electric circuit board (not shown) having a circuit (not shown) formed on the surface of a resin board or the like is used.

The connection pad 9 and the probe pin 8 are for electrically connecting the through conductor 2 (and the circuit conductor 7 electrically connected to the through conductor 2) to a predetermined terminal of the semiconductor element. The connection pad 9 can be formed by the same method using the same material as the conductor pad 3. The probe pin 8 is a wire made of a metal material having a columnar shape, a quadrangular columnar shape, an elliptical columnar shape or the like having a diameter of about 0.1 mm. For example, in order to facilitate connection to the semiconductor element, the probe pin 8 A portion folded in a “<” shape or the like is provided in a part of the wire, and can be connected to a semiconductor element with a certain elasticity.

  The electrical connection between the circuit conductor 7 and the metal pin P is performed by, for example, soldering. In this probe card, the metal pin P can be expanded and contracted in the length direction by, for example, a spring mechanism. That is, if the metal pin P can be expanded and contracted in the length direction, the length of the guide hole 5 and the thickness of the conductor pad 3 when the circuit board 6 is disposed on the main surface side where the auxiliary insulating layer 4 is exposed. Since the metal pin P expands and contracts in accordance with the distance between the circuit conductor 7 and the conductor pad 3 that may vary depending on the electric current between the circuit conductor 7 and the conductor pad 3 via the metal pin P. Connection can be made more easily and reliably.

  Further, if the metal pin P can be expanded and contracted in this way and the electrical connection between the circuit conductor 7 and the conductor pad 3 is facilitated, the wiring board or probe pin in which a defect occurs after the probe card is used. Usable parts (wiring boards and probe pins 8 with no defects) can be reused, such as replacing only 8 and reassembling. Also, during assembly (positioning of the wiring board and the circuit board 6 etc.), it is possible to readjust immediately when there is an electrical connection failure due to misalignment, etc. Can be. The circuit board 6 and the wiring board are temporarily fixed with a clip or the like while being aligned with each other.

  In such a probe card, a probe pin 8 for conducting an electrical test of a semiconductor element (IC or the like) is connected to the connection pad 9, and the conductor pad 3 is connected to the circuit conductor 7 of the circuit board 6. When a predetermined terminal of the semiconductor element is connected to the probe pin 8, the semiconductor element is electrically connected to the circuit conductor 7 through the probe pin 8, the connection pad 9, the through conductor 2, the conductor pad 3, and the metal pin P. The connected semiconductor device is inspected as to whether the integrated circuit of the semiconductor element operates normally (calculation, storage, etc.).

  For example, as shown in FIG. 4, the wiring board and the probe card of the present invention have a configuration in which the conductor pad 3 is provided with a convex portion 3 a whose side surface is located at the center of the guide hole 5 in plan view. In addition, since the side surface of the metal pin P is in contact with the side surface of the protrusion 3 a of the conductor pad 3, the connection area between the metal pin P and the conductor pad 3 can be further increased. Therefore, the electrical connection between the metal pin P and the conductor pad 3 can be performed more easily and with low resistance. FIG. 4 is a cross-sectional view showing another example of the embodiment of the wiring board and probe card of the present invention. 4, parts similar to those in FIG. 1 are denoted by the same reference numerals.

The convex portion 3a is formed in a circular shape or the like at the center of the circular conductive pad 3 or the like. The convex part 3a can be formed by the same method using the same material as the conductor pad 3 in parts other than the convex part 3a, for example. Moreover, what is necessary is just to make the thickness of the convex part 3a thicker than the thickness of the conductor pad 3 in the outer side rather than the convex part 3a. For example, if the conductor pad 3 including the convex portion 3a is made of a plating layer such as copper, the convex portion 3a is made thicker by about 5 to 15 μm than the other portions. In this case, if the thickness of the conductive pad 3 in the portion other than the convex portion 3a is 3 μm, the total thickness of the conductive pad 3 in the portion where the convex portion 3a is formed is about 8 to 18 μm.

  The conductor pad 3 having the convex portion 3a can be integrally formed including the convex portion 3a. That is, first, when the above-mentioned adhesion metal layer and a base conductor layer (not shown) are sequentially deposited on one main surface of the insulating layer 1, the convex portion 3a is formed by a partial plating method using masking together. In this part, the plating layer can be formed to be thicker than the others.

  The convex portion 3a is not limited to the cylindrical shape as described above, and in order to facilitate the connection with the metal pin P, the convex portion 3a has a shape (square prism shape or the like) in which the side surface located at the center portion of the guide hole 5 is planar. It may be a shape.

  That is, the convex portion 3a can be provided in various forms and positions as long as the side surface can contact the side surface of the metal pin P as shown in FIGS. . 5A to 5C show other examples of the embodiment of the wiring board and the probe card of the present invention, respectively, through the circuit board 6 and the auxiliary insulating layer 4 from the circuit board 6 side. It is a top view. 5, parts similar to those in FIGS. 1 and 4 are denoted by the same reference numerals.

  FIG. 5A shows a case where the convex portion 3a has a quadrangular shape in plan view. In this case, since the metal pin P contacts the flat side surface of the relatively wide convex portion 3a, electrical connection with the convex portion 3a of the metal pin P is easy. FIG. 5B shows a case where the convex portion 3a has a circular shape in plan view and the guide hole 5 has an elliptical shape. In this case, it is easy to guide the metal pin P to a predetermined position such as the short axis portion of the elliptical guide hole 5. Further, if the outer periphery of the circular convex portion 3a is positioned at this predetermined position, the electrical connection between the side surface of the convex portion 3a and the side surface of the metal pin P is easy. In FIG. 5C, a side surface of the convex portion 3a exposed in the guide hole 5 in a plan view is concave, and a cross section is circular along the concave surface (a side surface in contact with the convex portion 3a in a plan view). This is an example in which a metal pin P having a convex curved surface is easily connected.

  Moreover, the convex part 3a may be formed in the outer peripheral side of the conductor pad 3, as shown in FIG. FIG. 6 is a cross-sectional view showing another example of the embodiment of the wiring board and probe card of the present invention. In FIG. 6, the same parts as those in FIGS. 1 and 4 are denoted by the same reference numerals. When the convex portion 3a is formed on the outer peripheral side of the conductor pad 3, it is more effectively suppressed that the metal pin P is disengaged outside the conductor pad 3 (on one main surface of the insulating layer 1). The

  The protrusion 3 a on the outer peripheral side of the conductor pad 3 does not have to be formed over the entire outer periphery of the conductor pad 3, and at least a portion of the outer periphery of the conductor pad 3 that can be connected to the metal pin P. What is necessary is just to form in square shape, circular arc shape, etc.

  The present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the gist of the present invention. For example, a plurality of guide holes 5 may be formed for one conductor pad 3 as shown in FIG. In this case, by selecting and using these guide holes 5, it is possible to suppress wear due to contact of the conductor pads 3 with the metal pins P.

An insulating layer and an auxiliary insulating layer are each formed with a thickness of 2 mm by an aluminum oxide sintered body, and a through conductor having a diameter of about 0.5 mm is formed using copper for the insulating layer. A conductor pad having a diameter of about 0.7 mm was sequentially deposited by a titanium sputtering layer and a copper plating layer so as to cover the end face of the through conductor. The thickness of the conductor pad was about 5 μm. Further, the through conductor is formed by forming a through hole having a diameter of about 0.7 mm using a carbon dioxide laser in an insulating layer made of an aluminum oxide sintered body and filling the through hole with copper by an electroless plating method. Formed.

A guide hole having a diameter of about 0.7 mm is formed in the auxiliary insulating layer so that its outer peripheral portion is located on the outer periphery of the through conductor in plan view, and a conductor pad is formed on the opening on one main surface side of the insulating layer of the guide hole. Was exposed in a fan shape with a central angle of about 60 degrees.

  In addition, as a wiring board of a comparative example, the guide hole is positioned so that the center portion of the guide hole is located at the center portion of the through conductor in plan view (so that the guide hole and the through conductor are concentric with each other in plan view). ) A formed wiring board was prepared.

About the wiring board of these examples and the wiring board of the comparative example, a metal pin having a diameter of about 0.5 mm is repeatedly pressed with a force of about 0.39 N to check whether there is a defect such as a disconnection from the insulating layer in the through conductor. did. The presence or absence of defects was confirmed by visual observation using a projection device with a magnification of 100 times. Note that the number of through conductors and conductor pads was 1000 in both the examples and comparative examples.

  As a result, in the wiring board of the example, no defect was detected even after pressing the metal pin repeatedly for 500,000 times, whereas in the wiring board of the comparative example, a defect of poor connection occurred at a rate of 30%. It was. From the above results, the effect of suppressing the penetration of the through conductor from the insulating layer in the wiring board of the present invention could be confirmed.

DESCRIPTION OF SYMBOLS 1 ... Insulating layer 2 ... Through-conductor 3 ... Conductor pad 3a .... Projection part 4 ... Auxiliary insulating layer 5 ... Guide hole P ... Metal pin 6 ... Circuit board 7 ... ..Circuit conductor 8 ... probe pin 9 ... connection pad

Claims (3)

A wiring board comprising: an insulating layer having a through conductor penetrating in the thickness direction; and a conductor pad deposited from one main surface of the insulating layer to one end surface of the through conductor exposed to the one main surface side. The auxiliary insulating layer is laminated on one main surface of the insulating layer, and the central portion of the auxiliary insulating layer is outside the outer periphery of the through conductor and inside the outer periphery of the conductor pad in plan view. A wiring board that is located and has a guide hole that penetrates the auxiliary insulating layer in a thickness direction, and a portion of the conductor pad is exposed in the guide hole. The wiring board according to claim 1, wherein the conductive pad is provided with a convex portion whose side surface is located at a central portion of the guide hole in a plan view. 3. The wiring board according to claim 1 or 2 and a circuit conductor having one end of a metal pin joined thereto, arranged in contact with the exposed main surface of the insulating layer of the wiring board, and the metal A circuit board in which the circuit conductor is electrically connected to the conductor pad by pressing the other end of the pin against the conductor pad, and the other main surface side opposite to the one main surface of the wiring board And a probe pin electrically connected to the other end face of the exposed through conductor.

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