JP5015671B2 - Probe card - Google Patents

Description

  The present invention relates to a structure of a probe card used for inspecting electrical characteristics of chip devices integrated at high density on a semiconductor wafer, and a method for maintaining the plane parallelism of the probe substrate.

  2. Description of the Related Art Conventionally, as shown in FIG. 2 (a), a probe card used for inspection of electrical characteristics of a chip device on a semiconductor wafer includes a circuit board 4 to which a plurality of tester connection terminals 4a are connected, and a plurality of In order to electrically connect the probe board 3 to which the probe 2 is mounted, the connection terminal 5a of the circuit board 4 connected to the tester connection terminal 4a, and the connection terminal 3a of the probe board 3 connected to each probe 2. Relay connecting pins 5 having elasticity, a reinforcing plate 7 attached to the back surface of the circuit board 4 to reinforce mechanical strength, and a support body for holding the circuit board 4, the reinforcing plate 7, and the probe board 3 in a predetermined position. 8 and a support bolt 9. As shown in FIGS. 2B and 2C, the circuit board 4 and the probe board 3 are circular 3-1 or square 3-2 flat plates having a predetermined thickness. Further, the connection terminals 3 a and 5 a corresponding to the group of relay connection pins 5 are arranged in an orderly manner with respect to the circuit board 4 and the probe board 3. The relay connection pin 5 fixed to the circuit board 4 is an elastic body, and the tip of the relay connection pin 5 of the circuit board 4 and the corresponding connection terminal 3a of the probe board 3 are connected by a reaction force proportional to the pressing force. The electrical connection is ensured by pressure welding.

Prior art of a probe card employing such a structure is disclosed (Reference 1). This prior art employs a probe and a connector (corresponding to a relay connection pin) each having a structure having two arms, so that when the probe and the chip device which is an object to be inspected are pressed, It is possible to reduce the force transmitted to the support substrate.
Japanese Patent Laying-Open No. 2004-340617 ([0005-6], [0011-13], FIG. 18)

  This probe card has a structure in which corresponding connection terminals are electrically connected by a reaction force generated by pressing an elastic relay connection pin, and is applied to the probe board by a total load of reaction forces of a plurality of relay connection pins. Deflection occurred, and there was a problem that it was difficult to produce a desired product with the structure as it was. These problems are described in detail below.

  This relay connection pin is arranged between the circuit board and the probe board, and it is necessary to ensure the electrical connection between the two boards by the pressing force, so that a surface load acts on each of the boards in the vertical direction. (Γ in FIG. 3). The circuit board can sufficiently counter this surface load because the reinforcing plate is provided on the back side, but one probe board is a disk or flat plate whose peripheral part is simply supported by a support. The central portion of the wire is greatly bent (β line in FIG. 3). As a result, there arises a problem of impairing the plane parallelism (α line in FIG. 3) formed by the tip of the probe group fixed to the probe substrate. As shown in FIG. 3, this deformation is a mechanical phenomenon of occurrence of deflection when a disk or flat plate simply supported at the periphery receives a uniform surface load. The maximum deflection Wmax of the circle simply supported at the periphery and σmax of the maximum stress occur at the center of the disk and are given by Equation 1. (Reference: Mechanical Engineering Handbook edited by the Japan Society of Mechanical Engineers, 1984)

In this formula, the thickness of the plate is h, the diameter of the circular plate is 2a, the load per unit is p, the longitudinal elastic modulus of the plate material is E, and its Poisson's ratio is ν. When the diameter is 300 mm, the longitudinal elastic modulus is 300 GPa, the Poisson's ratio is 0.25, and the surface distribution load is 1.55 gf / mm ² , the deflection at the center of the disk reaches 300 μm and the maximum stress reaches 26 MPa. This physical property value corresponds to a high-strength ceramic material, and this surface distribution load density corresponds to disposing relay connection pins with a load of 10 gf at equal intervals of 2.54 mm. This deflection significantly impairs the surface parallelism of the probe substrate, and the parallelism of the tip surface of the probe group cannot be maintained. As a result, the electrode of the chip device formed on the semiconductor wafer having the flatness is highly accurate. It becomes impossible to contact.

  Actually, when the probe board is deformed by the surface distribution load, the load due to the relay connection pin is somewhat reduced according to the amount of deformation, and the actual deformation is that the pin load and the reaction force due to the deformation of the probe board are balanced. Therefore, although the actual deformation amount of the probe substrate is somewhat smaller than the above-mentioned calculated value, the problem remains that the probe substrate is deformed to deteriorate the plane parallelism. In addition, if the load of the relay connection pin is reduced in the center due to deformation of the probe board, the instability of the electrical contact remains correspondingly, so the load of the relay connection pin must be increased to avoid this. . This increases the load on the probe substrate, and there is a problem of assembling a probe card having a further deteriorated plane parallelism. The above-described prior art also has this fundamental problem.

  In view of the above circumstances, the present invention was made to solve these problems, and in a probe card used for inspection of electrical characteristics of chip devices integrated on a semiconductor wafer at a high density, The present invention provides a probe card that can favorably maintain the surface parallelism of the probe group tip and a method for maintaining the surface parallelism of the probe substrate.

  To achieve the above object, the invention of the probe card according to claim 1 is provided with a plurality of tester connection terminals on the upper surface and a first connection terminal group individually connected to the tester connection terminals on the lower surface. A circuit board and a second connection terminal group corresponding to each of the first connection terminals are disposed on the upper surface, and a plurality of probes individually connected to the second connection terminals are disposed on the lower surface. A plurality of resilient relay connection pins that are individually attached to the first connection terminals and elastically contact with and electrically connect to the second connection terminals; and In a probe card comprising a support body that supports a peripheral portion, and a support bolt that connects the support body to a circuit board and a reinforcing plate, a first connection terminal and a first connection terminal respectively corresponding to the plurality of relay connection pins Circuit with 2 connection terminals Intimately periphery for each plane of the plate and the probe substrate, and is characterized in that arranged sparsely central portion.

Further, the invention of the probe card according to claim 1 includes a circuit board in which a plurality of tester connection terminals are disposed on the upper surface and a first connection terminal group individually connected to the tester connection terminals is disposed on the lower surface, A probe board in which a second connection terminal group corresponding to each of the first connection terminals is disposed on the upper surface, and a plurality of probes individually connected to the second connection terminals are disposed on the lower surface; A plurality of resilient relay connection pins that are individually attached to the second connection terminals and that are elastically contacted and electrically connected to the first connection terminals, and a support that supports the peripheral edge of the probe board And a support bolt for coupling the support and the circuit board and the reinforcing plate, the circuit board includes a first connection terminal and a second connection terminal respectively corresponding to the plurality of relay connection pins. And probe board Intimately periphery to the plane, and characterized in that arranged sparsely central portion.

The invention of the present probe card, the probe card according to claim 1, wherein the circuit board and the probe substrate Ru flat der circular or rectangular.

    A plurality of relay connection pins fixed to the first or second connection terminal are attached to the circuit board and the reinforcing plate by a support to press-contact the second or first connection terminal to ensure electrical connection. As a result of the movement of the probe substrate, the relay connection pin group, which is an elastic body, is moderately deformed, and electrical connection is achieved by a pressure contact force caused by a reaction force proportional to the pressing amount. At this time, the relay connection pins and the corresponding first or second connection terminals are densely arranged on the periphery of the probe board and the circuit board, and the center part is sparsely arranged, so that the relay connection pins are connected to the probe board. By making the surface distribution load smaller in the central portion than in the peripheral portion, the deflection of the central portion of the probe substrate can be reduced. For example, when the connection terminals are arranged with an arrangement pitch between the second connection terminals on the probe substrate at the center portion that is twice as large as that of the peripheral portion, the magnitude of the surface distribution load at the center portion Becomes as small as 1/4 of the surface distribution load of the peripheral portion. As a result, the plane parallelism formed by the tips of the probe groups arranged on the lower surface of the probe substrate can be maintained, so that the tip of the probe and the tip can be used when inspecting a device having a high degree of flatness formed on a semiconductor wafer. Contact with the electrodes of the device can be made reliably and accurate measurement is possible.

Further, method of holding the plane parallelism of the probe substrate is a circuit board which is disposed a first connecting terminal groups, which are individually connected to the tester connection terminals on the lower surface as well as arranging a plurality of tester connection terminals on the upper surface A probe board having a plurality of probes connected individually to the second connection terminals on the lower surface, and a second connection terminal group individually corresponding to the first connection terminals; A plurality of resilient relay connection pins individually attached to the first connection terminals and elastically contacting and electrically connecting to the second connection terminals, and supporting a peripheral portion of the probe board A probe card comprising: a support body; and a support bolt that couples the support body to the circuit board and the reinforcing plate. First connection terminal The second connection terminals are arranged with a dense peripheral portion and a sparse central portion with respect to each plane of the circuit board and the probe board, and the surface distribution load density brought about by the plurality of relay connection pins on the probe board is reduced. keep the plane parallelism of the probe substrate by reducing the perimeter stepwise or continuously toward the center portion.

Further, method of holding the plane parallelism of the probe substrate is a circuit board which is disposed a first connecting terminal groups, which are individually connected to the tester connection terminals on the lower surface as well as arranging a plurality of tester connection terminals on the upper surface A probe board having a plurality of probes connected individually to the second connection terminals on the lower surface, and a second connection terminal group individually corresponding to the first connection terminals; A plurality of resilient relay connection pins individually attached to the second connection terminals and elastically contacting and electrically connecting to the first connection terminals, and supporting a peripheral edge of the probe board A probe card comprising: a support body; and support bolts that connect the support body to the circuit board and the reinforcing plate. The probe card is a method for maintaining the surface parallelism of the probe board, and corresponds to each of the plurality of relay connection pins. First connection terminal The second connection terminals are arranged with a dense peripheral portion and a sparse central portion with respect to each plane of the circuit board and the probe board, and the surface distribution load density brought about by the plurality of relay connection pins on the probe board is reduced. keep the plane parallelism of the probe substrate by reducing the perimeter stepwise or continuously toward the center portion.

Further, method of holding the plane parallelism of the probe substrate, the method of holding the plane parallelism of the probe substrate, the circuit board corresponding to the probe substrate Ru flat der circular or rectangular.

  To ensure contact between the tip of the probe and the electrode of the chip device when inspecting the chip device, and to enable accurate measurement, the surface parallelism of the probe substrate loaded with the pressing force of the relay connection pins is maintained. This is important because it leads to maintaining the parallelism of the probe group tip of the probe substrate. The pressing force by the relay connecting pin group is loaded on the probe board and the circuit board, respectively, but the circuit board is reinforced by the reinforcing plate on the back surface, and there is a dimensional margin, so that the structure does not cause deflection. However, on the other hand, the probe substrate also has dimensional constraints, and it is difficult to increase the strength against bending. In addition, since the probe substrate having a circular shape or a square shape has a structure in which the peripheral portion is supported on the lower support by the support, the peripheral portion has high rigidity. As a method of maintaining the surface parallelism of the probe board under this situation, the surface parallelism can be reduced in a stepwise or continuous manner from the peripheral part to the central part by reducing the surface distribution load density that the relay connection pin group brings to the probe board. The arrangement of the second connection terminal group that can be maintained, specifically, press-contacts or adheres to the relay connection pin group that constitutes the pressing point to the probe board, the probe board has a peripheral part densely arranged in the center part Is a sparse arrangement method.

According to the probe card of the configuration of the first aspect of the present invention, the arrangement of the relay connection pins and the corresponding connection terminals is arranged close to the peripheral part of the probe board and the central part is made sparse so that the central part of the probe board is arranged. By making the surface distribution load smaller than the peripheral portion, the deflection of the central portion of the probe substrate can be reduced, so that the surface parallelism formed by the tip portion of the probe group disposed on the lower surface of the probe substrate can be maintained. . Thereby, the contact between the probe tip and the electrode of the chip device can be reliably performed during the inspection of the chip device, and the semiconductor wafer can be inspected accurately.

According to the method the holding surface parallelism of the onset Ming probe substrate, the method relay connection pin group reduces stepwise or continuously toward the center portion from the peripheral portion of the surface distributed load density to bring the probe substrate, i.e. the probe The arrangement of the second connection terminal group that is in pressure contact with or fixed to the relay connection pin group that constitutes the pressing point to the board, by a simple method in which the peripheral part of the probe board is densely arranged and the central part is sparsely arranged, Since the deflection of the central portion of the probe substrate can be reduced, the plane parallelism formed by the tip portion of the probe group disposed on the lower surface of the probe substrate can be maintained. Thereby, the contact between the probe tip and the electrode of the chip device can be reliably performed during the inspection of the chip device, and the semiconductor wafer can be inspected accurately.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an embodiment of a probe card according to the present invention, in which a is a schematic sectional view of the probe card, b is a schematic plan view of connection terminals of a circular probe substrate in a, and c is a rectangular probe in a. It is a typical plane arrangement view of a connection terminal of a substrate.

  The probe card 1 according to the embodiment of the present invention will be described with reference to FIGS. 1A, 1B, and 1C. The probe card 1 has a plurality of tester connection terminals 4a disposed on the upper surface. A circuit board 4 having a group of connection terminals 5a individually connected to the tester connection terminal 4a arranged on the lower surface, and a group of connection terminals 3a corresponding to the connection terminals 5a arranged on the upper surface and individually connected to the connection terminals 3a. A probe board 3 in which a plurality of connected probes 2 are arranged on the lower surface; and a group of relay connection pins 5 having elasticity arranged in a cantilever shape with a root fixed to the connection terminal 5a of the circuit board 4; The reinforcing plate 7 is in close contact with the back surface of the circuit board 4 and reinforces the mechanical strength. The circuit board 4, the reinforcing plate 7, and the support body 8 that holds the probe board 3 in a predetermined position and the support bolt 9 are included.

  The probe board 3 and the circuit board 4 are circular or square flat plates having a predetermined thickness. The substrates 3 and 4 are synthetic resin printed boards. In the probe substrate 3, the connection terminals 3a on the upper surface and the corresponding probe connection terminals 3b on the lower surface are internally connected by printed wiring, Also in the circuit board 4, each tester connection terminal 4a and a corresponding connection terminal 5a on the lower surface are internally connected by printed wiring. Probes 2 corresponding to electrode pads of a semiconductor chip device, which is an object to be measured, are arranged in an orderly manner on the entire lower surface of a circular or square probe substrate 3. These probes 2 are fixed to the probe connection terminals 3b of the probe substrate 3, hold the probe 2 body in a cantilever shape, and can be contacted with an electrode pad (not shown) of the chip device on the tip thereof. Have The wire diameter of the probe 2 is in the range of 20 to 200 μm depending on the scale of the chip device, and the number of probes is on the scale of several hundred to several tens of thousands. As the material of the probe 2, one kind of alloy selected from nickel alloy, palladium alloy, beryllium copper alloy, tungsten alloy and the like is usually used.

  Further, the reinforcing plate 7 is used to reinforce the back surface for maintaining the flatness of the substrate 6. In this case, it is desirable to use a metal having high strength and to use stainless steel or aluminum from the viewpoint of heat resistance, weather resistance, contamination resistance and workability. Further, in order to optimally adjust the pressing force of the relay connection pin 5 that holds the electrical connection by adjusting the vertical distance between the probe board 3 and the circuit board 4, the lower end surface of the peripheral edge of the probe board 3 is simply supported. A metal support 8 to be supported is provided, and the position of the support 8 can be adjusted by a support bolt 9 penetrating the reinforcing plate 7 and the circuit board 4.

  The relay connection pin 5 fixed to the circuit board 4 is an elastic body, and the tip of the relay connection pin 5 of the circuit board 4 and the corresponding connection terminal 3a of the probe board 3 are connected by a reaction force proportional to the pressing force. The electrical connection is ensured by pressure welding. The shape of the relay connection pin 5 is such that a reaction force is generated by the pressing force accompanying the compression of the elastic material, and the horizontal positional relationship between the connection terminal 5a that is the root to which the relay connection pin 5 is fixed and the corresponding connection terminal 3a. Therefore, the cantilever type cantilever type or the coil spring type is preferable, and the cantilever type is preferable in terms of easy manufacture. The material of the relay connection pin 5 is preferably a material having elasticity and good electrical conductivity, and a phosphorous copper alloy, a beryllium copper alloy, a nickel alloy, or the like is used.

  As shown in FIG. 1B, the arrangement of the connection terminals 3a of the probe board 3 corresponding to the relay connection pins 5 is such that the connection terminal 3a group is substantially concentric in the circular flat plate probe board 3-1. The arrangement pitch (interval) p1 of the adjacent connection terminals 3a in FIG. 3 is smaller than the arrangement pitch (interval) p2 of the adjacent connection terminals 3a in the center. In this case, the arrangement pitch of the connection terminals 3a from the peripheral part to the central part can be changed stepwise or continuously. Based on the arrangement position of the connection terminals 3a, the connection terminals 5a of the circuit board 4 to which the roots of the relay connection pins 5 and the relay connection pins 5 are fixed are arranged. Further, as shown in FIG. 1C, in the rectangular flat probe board 3-2, the connection terminal 3a group has a shape in which the four corners of the substantially concentric circles are shaped into a square, and the adjacent connection terminals 3a in the peripheral portion are formed. The arrangement pitch (interval) p1 is smaller than the arrangement pitch (interval) p2 of the adjacent connection terminals 3a in the central part, and the arrangement pitch of the connection terminals 3a from the peripheral part to the central part is stepwise or Can be changed continuously. Based on the arrangement position of the connection terminals 3a, the connection terminals 5a of the circuit board 4 for fixing the roots of the relay connection pins 5 and the relay connection pins 5 are also arranged. For example, if the connection terminals 3a are arranged at a pitch twice as large as the arrangement pitch p2 at the center of the connection terminals 3a on the probe substrate 3 as compared to the arrangement pitch p1 at the periphery, the surface distribution by the relay connection pins 5 at the center. The magnitude of the load is reduced to 1/4 of the surface distribution load in the peripheral portion. Further, in the above-described arrangement example, it can be said that the number distribution from the peripheral part to the central part of the group of connection terminals 3a on the probe substrate 3 approximates a normal distribution. In this way, the arrangement of the connection terminal 3a group that press-contacts the relay connection pin 5 group that constitutes the pressing point to the probe substrate 3 is arranged so that the peripheral portion of the probe substrate 3 is dense and the central portion is sparse. By reducing the surface distribution load density brought about by the relay connection pins 5 to the probe board stepwise or continuously from the peripheral part to the central part, the deflection of the central part of the probe board 3 can be prevented, and the plane parallel of the probe board 3 can be prevented. The degree can be maintained.

  In addition, the probe card 1 which is another embodiment of the probe card according to the present invention will be described with respect to differences from FIGS. 1A, 1B, and 1C. The probe card 1 is connected to a plurality of testers. A circuit board 4 having terminals 4a arranged on the upper surface and connecting terminals 5a individually connected to the tester connection terminals 4a arranged on the lower surface, and connection terminals 3a corresponding to the connection terminals 5a individually arranged on the upper surface. And a probe substrate 3 having a plurality of probes 2 individually connected to the connection terminal 3a disposed on the lower surface thereof, and an elasticity disposed in a cantilever shape with the root fixed to the connection terminal 3a of the probe substrate 3. A relay connection pin 5 group having a reinforcing plate 7 that is in close contact with the back surface of the circuit board 4 and reinforces the mechanical strength, and a support body 8 that holds the circuit board 4, the reinforcement plate 7, and the probe board 3 in a predetermined position. Support bolt 9 Et al constructed. The relay connection pin 5 fixed to the probe board 3 is an elastic body, and the tip of the relay connection pin 5 of the probe board 3 presses the corresponding connection terminal 5a of the circuit board 4 by a reaction force proportional to the pressing force. Thus, electrical connection is ensured. At this time, one reaction force of the relay connection pin 5 due to the pressing force is also applied to the connection terminal 3a to which the relay connection pin 5 is fixed. Therefore, as described above, the arrangement of the connection terminal 3a group to be fixed to the group of relay connection pins 5 constituting the pressing point to the probe board 3 is arranged with the peripheral part of the probe board 3 being dense and the central part being sparse. By doing so, the surface distribution load density brought to the probe board by the relay connection pins 5 group can be reduced stepwise or continuously from the peripheral part to the central part, so that the deflection of the central part of the probe board 3 can be prevented. 3 plane parallelism can be maintained.

  The feature of the action of the probe card 1 according to the present invention is that the arrangement of the relay connection pins 5 constituting the surface distribution load on the probe substrate 3 and the connection terminals 3a which are pressed against or fixed to each other is arranged in the peripheral portion of the probe substrate 3. By arranging them densely and sparsely in the central part, the surface distribution load density brought to the probe board by the group of relay connection pins 5 can be reduced stepwise or continuously from the peripheral part to the central part. Deflection of the center portion of the probe substrate 3 can be prevented, and the surface parallelism of the probe substrate 3 can be maintained. As a result, the surface parallelism formed by the tips of the probe groups disposed on the lower surface of the probe substrate can be maintained, so that the tip of the probe and the electrode of the tip device can be reliably contacted when the tip device is inspected. Enable measurement. In addition, the reliability of the electrical connection of the probe card during inspection can be maintained even in a test environment that involves mechanical shocks when contacting the electrodes of the chip device. It is possible to avoid the economic loss that would be judged.

  In a semiconductor wafer, it can be used for a probe card used for inspection of electrical characteristics of a highly integrated IC chip.

1 is a schematic cross-sectional view of a probe card, b is a schematic plan view of connection terminals of a circular probe board in a, and c is a connection terminal of a rectangular probe board in a. FIG. A conventional probe card, wherein a is a schematic cross-sectional view of the probe card, b is a schematic plan view of connection terminals of a circular probe board in a, and c is a schematic plan view of connection terminals of a rectangular probe board in a. FIG. FIG. 3 is a schematic cross-sectional view of the probe card when a pressing force is applied by the relay connection pin group in FIG. 2.

Explanation of symbols

1: Probe card 2: Probe 3: Probe board 3-1: Circular probe board 3-2: Rectangular probe board 3a: Connection terminal 3b: Probe connection terminal 4: Circuit board 4a: Tester connection terminal 5: Relay connection pin 5a: Connection terminal 7: Reinforcement plate 8: Support body 9: Support bolt
α: tip line of the probe group β: deflection of the probe substrate γ: surface distribution load p1: arrangement pitch of connection terminals in the peripheral portion p2: arrangement pitch of connection terminals in the central portion

Claims (1)

A circuit board having a plurality of tester connection terminals disposed on the upper surface and a first connection terminal group individually connected to the tester connection terminals disposed on the lower surface, and a first corresponding to each of the first connection terminals. Two connection terminal groups on the upper surface and a plurality of probes individually connected to the second connection terminal on the lower surface, and the first connection terminal or the second connection terminal . A plurality of elastic relay connection pins that are individually attached and elastically contact and electrically connect to the second connection terminal or the first connection terminal , and a support that supports the peripheral portion of the probe board If the support bolt for coupling the said support and said circuit board and the reinforcing plate, the probe card consists of the plurality of relay connection pins and each corresponding said first connecting terminal and said second connecting terminal the circuit board and the probe group Probe card for dense peripheral portion, characterized in that arranged sparsely central portion with respect to each plane of the.

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