JP5065626B2 - Probe card - Google Patents

Description

  The present invention relates to a structure of a probe card used for inspecting electrical characteristics of chips densely integrated on a semiconductor wafer.

  Conventionally, a probe card used for inspection of electrical characteristics of a chip device on a semiconductor wafer has a structure in which a probe support unit 4 that supports a probe 3 is fixed to a reinforcing plate 7 and suspended as shown in FIG. Is adopted. The probe support unit 4 is usually composed of a ceramic support plate 4-2 and an epoxy resin fixing portion 4-1 for supporting the probe 3, and the reinforcing plate 7 is made of a metal plate such as stainless steel. . An epoxy resin 13 is used to fix both of them. Further, the reinforcing plate is made of a metal having good heat conduction, and the area of the probe card is larger as the probe card is larger. Therefore, the reinforcing plate is more susceptible to thermal influence such as thermal expansion than the probe support unit, and the thermal displacement is large. As a result, since the support unit supporting the probe is fixed to the reinforcing plate, the support unit is directly affected by the thermal expansion and contraction of the reinforcing plate, and the probe tip position is moved. In other words, when testing a semiconductor wafer at a high temperature, the probe tip moves in a direction extending with respect to the needle base (the needle trace is inward), and conversely at a low temperature, the needle tip moves in a contracting direction (the needle trace is outward). )There is a tendency. If this tendency is great, the needle traces protrude from the electrode pads of the LSI chip. Even if this tendency is small, if the tip becomes large and the electrode pad is small, the needle traces will also protrude from the electrode pad.

The prior art for preventing the adverse effect of the semiconductor wafer inspection due to the movement of the needle trace position is disclosed (Reference 1). Prior to high-temperature inspection of the wafer, this technique sets the probe card to a high temperature state and transfers the needle traces of all the probes onto the transfer sheet, thereby imaging the position coordinate data of all the probes and the position coordinate data of the needle traces. Obtained by processing and arithmetic processing, and then, by accurately aligning the wafer to be inspected with respect to the probe card based on this data, all the probes are accurately brought into contact with the corresponding electrode pads so that the reliability is high. It can be inspected.
Japanese Patent Laying-Open No. 2005-79253 ([0034], FIG. 2)

  The above-described inspection method and inspection apparatus perform operations that require grasping the behavior of the needle traces of all probes for each probe card under temperature control (for example, under high temperature conditions) prior to inspection of a semiconductor wafer. In other words, there is a problem that the complexity and the cost of the image of the needle trace for the work, the equipment cost of the processing device required for the arithmetic processing, the processing software, and the like increase.

The present invention has been made in order to solve these problems in view of the above circumstances, and in a probe card used for inspection of electrical characteristics of chips integrated on a semiconductor wafer at high density, In order to maintain the mechanical strength, especially when the probe card itself is large, the solution to thermal deformation or thermal displacement due to the reinforcing plate is reduced. It is important to provide a probe card capable of accurately inspecting a semiconductor wafer even under temperature control (for example, at a high temperature or a low temperature) by simple modification without greatly changing the structure of a conventional probe card. Is.

In order to achieve the above object, the invention of the probe card according to claim 1 covers the substrate on which a plurality of openings spaced apart from each other corresponding to the inspection region are opened, and covers the opening on the surface side of the substrate. A plurality of reinforcing plates provided on the back side of the substrate, and a probe supporting unit held so as to be slidable with respect to the reinforcing plate through the opening, and the plurality of supporting units. And a coupling member that is integrally coupled at a predetermined interval. Further, the invention is a probe card according to claim 2, in the probe card according to claim 1, wherein the coupling member for integrally coupling said plurality of support units extends diagonally of the inspection area of each support unit member It is characterized by being.

  By adopting this configuration, when a semiconductor wafer is inspected under temperature control (for example, under high or low temperature conditions), there is an influence of thermal deformation or thermal displacement on the probe card substrate or the reinforcing plate, particularly metal. The manufactured reinforcing plate has a large coefficient of thermal expansion and a large thermal displacement due to temperature, but in order to eliminate this adverse effect, the support unit is slidable relative to the substrate or the reinforcing plate. Since it is held, the influence of the thermal deformation or thermal displacement of the substrate or the reinforcing plate does not cause the position variation of the support unit that supports the probe intermediate portion. Therefore, since the present invention has a structure limited to the thermal expansion / contraction of the support unit alone, the position variation of the probe base represented by the cantilever type and the intermediate support unit can be extremely reduced. It is possible to almost eliminate the movement of the position of the needle tip.

  Moreover, although the said support unit respond | corresponds to one test | inspection area | region, although the some support unit is comprised in the probe card which has several test | inspection area | region, each support unit is also with respect to a board | substrate or a reinforcement board. As described above, each support unit is held so as to be relatively slidable. Therefore, the probe card of the present invention can maintain the accuracy of the position of the probe tip because the support unit is independent of movement of the substrate or auxiliary plate in a high temperature or low temperature state and is independent. In addition, when inspecting a semiconductor wafer, the position data of the needle tip at room temperature can be utilized in a high temperature or low temperature state.

The probe card according to the present invention is characterized in that, in the probe card according to claim 1, the plurality of sets of support units are coupled and integrated at a predetermined interval by a coupling member.

  In the case of a probe card in which a plurality of inspection areas are set so as to simultaneously contact the electrodes of a plurality of chips, the interval between the inspection areas changes according to thermal expansion or thermal contraction. Therefore, control corresponding to thermal deformation or thermal displacement is required for each inspection region, and at the same time, it is required to cope with thermal deformation or thermal displacement between inspection regions. In the present invention, a plurality of inspection areas are combined and integrated so that they can slide independently of the substrate or the reinforcing plate, so that simple design conditions can be set without complicated control. It can be handled with. That is, the material of the support unit and the coupling member based on the coefficient of thermal expansion set based on conditions such as the coefficient of thermal expansion of the semiconductor wafer, the temperature distribution conditions during the inspection, and the distance between the semiconductor wafer and the probe card during the inspection. Can be set. Thereby, even if a plurality of sets of support units are configured in a probe card having a plurality of inspection areas, each support unit is slidably held with respect to the substrate or the reinforcing plate, and a plurality of sets of support units are supported. By combining the units with each other at a predetermined interval, the relative position of each support unit can be eliminated, and when inspecting multiple inspection areas simultaneously, the position accuracy of the probe needle tip is correct. Can be secured.

The invention of the present probe card, the probe card according to claim 1 or 2, that is held by the reinforcing plate by fitting the support unit via the easy sliding member. The invention of the present probe card, the easily sliding member is, that consists of a Ekisurido resin plate and easy slidability washer. The invention of the present probe card, the said easy sliding resin plate easy sliding property washer is made of fluorine resin.

  By adopting these configurations, the support unit can be slidable relative to the substrate or the reinforcing plate. In addition, a slidable resin plate is sandwiched between the support unit and the substrate or the auxiliary plate, and a coupler (for example, a screw) that couples the support unit to the substrate or the reinforcing plate at right angles to the sliding direction. In addition, since the slidable washer is interposed in the gripper), the support unit is not restricted by thermal deformation or thermal displacement of the substrate or the auxiliary plate. Further, as the slidable resin plate, a fluorine resin having a low friction coefficient and excellent in heat resistance and electrical insulation is used. The support unit includes a support plate and a fixed resin portion that fixes the support plate and the probe.

According to the probe card having the structure of claims 1 to 2 according to the present invention, since it has a simple structure and can maintain the accuracy of the needle trace regardless of the temperature condition, it is necessary to greatly change the structure of the conventional probe card. The temperature of the probe tip is not limited by the movement of the auxiliary plate even under temperature control, for example, when changing to a high or low temperature state, or when the temperature changes due to the progress of the test. Therefore, the semiconductor wafer can be accurately inspected. Also, the position data of the needle tip at room temperature can be used when inspecting a semiconductor wafer. Further, the present invention can be sufficiently applied to a structure having a probe with a small needle outer diameter and interval as a probe necessary for inspection of a highly integrated chip. In addition, there is a convenience that does not require warming up of the probe card at the start of inspection. Further, the present invention, it is possible to apply to a probe card having inspection area multiple, it can exhibit a sufficient effect when used for inspection of semiconductor wafers at a temperature regulation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a probe card according to an embodiment of the present invention, in which a is a schematic plan view, b is a schematic cross-sectional view, and c is an enlarged view of part A of b. 2A is a cross-sectional view of another embodiment in FIG. 1, and b is an enlarged view of a part A of FIG. FIG. 3 is a probe card according to another embodiment of the present invention, which has a plurality of inspection areas, a is a schematic sectional view of a probe card, b is a schematic sectional view of another probe card, c is a schematic plan view of the coupling member in a and b.

  A probe card 1 according to an embodiment of the present invention will be described with reference to FIG. 1. The probe card 1 mainly includes a plurality of cantilever type probes 3 (hereinafter referred to as probes) and a needle contact of the probe 3. The substrate 6 is configured to support the intermediate portion of the probe 3, and the slidable resin plate 5 is sandwiched between the support unit 4 and the substrate 6. The support unit 4 includes a support plate 4-2 for accurately positioning the probe tips of the group of probes 3 and a resin fixing unit 4- for fixing the support plate 4-2 and an intermediate portion of the group of probes 3 to each other. 1. With this configuration, the probe 3 has a needle base fixed to the substrate 6 and an intermediate portion fixed to the support unit 4. Therefore, since the probe 3 is fixed on both surfaces of the substrate 6 and the support plate 4-2, the position of the needle tip that is a free end is also fixed.

  The support plate 4-2 is a flat plate having an annular shape. As the annular shape, any of a circle, an oval, and a rectangle (including a square) is exhibited. Further, the support plate 4-2 is optimally used a ceramic material in terms of heat resistance, strength, and coefficient of thermal expansion, and since the shape change with respect to the temperature change is extremely small and high strength, The positional accuracy of the resin fixing portion 4-1 fixed to the support plate 4-2 can be improved, and as a result, the positional accuracy of the probe tip of the probe 3 can be ensured correctly. The resin fixing part 4-1 is usually formed by integrally fixing the probe 3 group and the support plate 4-2 using an epoxy resin for high temperature.

  The substrate 6 is a printed board made of synthetic resin that surrounds and arranges the support plate 4-2, and is intended to connect the probe base of the group of probes 3 to an electrical inspection processing device (not shown). is there. In order to increase the position accuracy of the probe tip of the probe 3, it is desirable that the substrate 6 and the support plate 4-2 forming the support unit 4 are integrally coupled.

  Further, the reinforcing plate 7 (illustrated with a chain line) may be used to reinforce the back surface for maintaining the flatness of the substrate 6. In this case, a metal having high strength is used, and heat resistance, weather resistance, It is desirable to use stainless steel from the viewpoint of stain resistance and workability.

    The support plate 4-2 is screwed up and down by a plurality of pan screws 8 on the substrate 6 through the slidable resin plate 5. Thereby, the support plate 4-2 of the probe card 1 has a structure in which the support plate 4-2 is screwed from the substrate 6 by a plurality of pan screws 8 and suspended. As shown in FIG. 1c, when the pan screw 8 screws the support plate 4-2 onto the substrate 6, the pan screw hole penetrating the support plate 4-2 is drilled larger than the screw diameter, and The head of the screw is fixed to the surface of the support plate 4-2 through a fluorine resin washer 10 and a metal washer 9 which are easy-to-slidable washers. Therefore, even if the substrate 6 is displaced in a plane along the probe 3, the substrate 6 can slide freely with respect to the support plate 4-2, so that the support plate 4-2 can maintain its position. . The support plate 4-2 is held on the substrate 6 by a pan screw 8 in the vertical direction. That is, even if thermal deformation or thermal displacement occurs in the substrate 6, the support plate 4-2 is not affected by the deformation or displacement in the axial direction of the probe 3 group. As the fluororesin, polytetrafluoroethylene, perfluoroalkoxyalkane, perfluoroethylene propene copolymer, ethylene-tetrafluoroethylene copolymer, and the like can be used, and the most suitable one is polytetrafluoroethylene.

  The operation of the probe card 1 according to the present invention will be described. In a hot burn test in a high temperature state (85 to 150 ° C.) or a cold test in a low temperature state (−20 to −40 ° C.), the probe is compared with that at room temperature. When a temperature change is caused to the card 1, even if the synthetic resin substrate 6 has a larger thermal deformation or thermal displacement due to the temperature change than the ceramic support plate 4-2, the thermal deformation or thermal displacement is not affected. In addition, since the slidable resin plate 5 typified by fluorine resin is interposed between the substrate 6 and the support plate 4-2, it is easy to slide in the direction parallel to the plate surface. The support plate 4-2 is not constrained by deformation or displacement of the substrate 6, maintains the current position, and does not shift.

  Therefore, the support plate 4-2 is relatively slidable against the thermal deformation or thermal displacement of the substrate 6 caused by the temperature change applied to the probe card 1 of the present invention. 2 does not change its position. Therefore, the position of the resin fixing portion 4-1 does not change, and the support position of the intermediate portion of the probe 3 does not change. Accordingly, since the position variation of the probe tip of the group of probes 3 is extremely small, the needle trace of the needle tip due to overdrive at the time of inspection does not come off from the electrode pad of the semiconductor chip, and normal electrical characteristics of the semiconductor chip can be inspected. It can be carried out.

  The probe card 1 according to another embodiment of the present invention will be described mainly with respect to the points different from FIG. 1 with reference to FIG. 2. The probe card 1 mainly includes a plurality of cantilever probes 3 (hereinafter referred to as probes). The substrate 6 that makes electrical contact at the probe base of the probe 3, the support unit 4 that supports the intermediate portion of the probe 3, the support unit 4 is reinforced in a plane, and the opening 12 of the substrate 6 A reinforcing plate 7 that reinforces the substrate 6 so as to cover the substrate, and a slidable resin plate 5 that is sandwiched between the support unit 4 and the reinforcing plate 7. The support unit 4 includes a support plate 4-2 for accurately positioning the probe tips of the group of probes 3 and a resin fixing unit 4- for fixing the support plate 4-2 and an intermediate portion of the group of probes 3 to each other. 1. With this configuration, the probe 3 has a needle base fixed to the substrate 6 and an intermediate portion fixed to the support unit 4. Therefore, since the probe 3 is fixed on both surfaces of the substrate 6 and the support plate 4-2, the position of the needle tip that is a free end is also fixed.

  The support plate 4-2 is formed of a flat plate having an annular shape, and forms an opening 12 including an inspection region 2 where a needle tip protruding from the group of probes 3 faces in the center. As the annular shape, any of a circle, an oval, and a rectangle (including a square) is exhibited. Also, the support plate 4-2 is heat resistant, strong, and optimal to use a ceramic material in terms of a low coefficient of thermal expansion, has very little shape change with respect to temperature change, and has high strength. At a certain point, the positional accuracy of the resin fixing part 4-1 fixed to the support plate 4-2 is improved. The resin fixing part 4-1 is usually formed by integrally fixing the probe 3 group and the support plate 4-2 using an epoxy resin for high temperature.

  The reinforcing plate 7 is a plate that reinforces the back surface for maintaining the flatness of the support plate 4-2, and is made of a metal having high strength, and has heat resistance, weather resistance, contamination resistance, and workability. From the viewpoint of properties, it is desirable to use stainless steel.

    The support plate 4-2 is screwed up and down by a plurality of pan screws 8 on the reinforcing plate 7 through the slidable resin plate 5. As a result, the support plate 4-2 of the probe card 1 has a structure in which the support plate 4-2 is screwed from the reinforcing plate 7 by a plurality of pan screws 8 and suspended. As shown in FIG. 2b, when the pan screw 8 screws the support plate 4-2 to the reinforcing plate 7, the pan screw hole penetrating the support plate 4-2 is drilled larger than the screw diameter, and The head of the pan screw is fixed to the surface of the support plate 4-2 through a fluorine resin washer 10 and a metal washer 9. Therefore, even if the reinforcing plate 7 causes a planar displacement along the probe 3, the support plate 4-2 is not constrained to this, and independently holds the position by sliding freely. However, the reinforcing plate 7 is supported by the support plate 4-2 with a pan screw 8 in the vertical direction. That is, even if thermal deformation or thermal displacement occurs in the reinforcing plate 7, the support plate 4-2 is not affected by the deformation or displacement with respect to the axial direction of the group of probes 3.

  The operation of the probe card 1 according to the present invention will be described. In a hot burn test in a high temperature state (85 to 150 ° C.) or a cold test in a low temperature state (−20 to −40 ° C.), the probe is compared with that at room temperature. When the card 1 is changed in temperature, the reinforcing plate 7 is made of metal (especially stainless steel), so that thermal deformation or thermal displacement due to temperature change is larger than that of the ceramic support plate 4-2. In response to this thermal displacement, the slidable resin plate 5 typified by fluororesin is interposed between the reinforcing plate 7 and the support plate 4-2. The support plate 4-2 is not restricted by the displacement of the reinforcing plate 7, maintains the current position, and is not displaced.

  Therefore, since the support plate 4-2 is relatively independent of the thermal displacement of the reinforcing plate 7 caused by the temperature change applied to the probe card 1 of the present invention, the support plate 4-2 is of course supported. The resin fixing portion 4-1 coupled to the plate 4-2 does not change its position. Therefore, there is no position fluctuation of the support unit 4 that supports the intermediate part of the probe 3, the position fluctuation of the needle tips of the group of probes 3 can be extremely reduced, and the needle trace of the needle tip due to overdrive at the time of inspection is the electrode pad of the semiconductor chip. Therefore, the electrical characteristics of the normal semiconductor chip can be inspected.

  FIG. 3 shows a probe card 1 according to another embodiment of the present invention, which has a plurality of inspection areas arranged to face a wafer to be inspected. In the case of a probe card in which a plurality of inspection areas are set so as to simultaneously contact the electrodes of a plurality of chips, the interval between the inspection areas changes according to thermal expansion or thermal contraction. Therefore, control corresponding to thermal deformation or thermal displacement is required for each inspection region, and at the same time, it is required to cope with thermal deformation or thermal displacement between inspection regions. In the present invention, a plurality of inspection areas are combined and integrated so that they can slide independently of the substrate or the reinforcing plate, so that simple design conditions can be set without complicated control. It can be handled with. That is, the material of the support unit and the coupling member based on the coefficient of thermal expansion set based on conditions such as the coefficient of thermal expansion of the semiconductor wafer, the temperature distribution conditions during the inspection, and the distance between the semiconductor wafer and the probe card during the inspection. Can be set. In this embodiment, the inspection areas are set at the four corners of the square. However, the arrangement may be arbitrarily changed when more inspection areas are provided.

  FIG. 3c shows a schematic plan view of the probe card 1 in which four inspection areas 2 are arranged at square corners. In each probe area, a plurality of probes 3 that perform electrical measurement in contact with electrodes (not shown) of the chip to be measured are arranged centripetally from the peripheral edge of the central inspection region 2 to the electrodes to be measured. The probe 3 group has a structure in which the needle base portion is supported by the substrate 6 and the intermediate portion is supported by the resin fixing portion 4-1 that is fixed to the support plate 4-2 that is the support unit 4. Further, in the case of the present embodiment, the coupling member 11 has a shape extending in all directions having a cross-shaped coupling portion or a shape extending in an oblique diagonal direction, and an inspection region 2 having an opening at each end. Formed and integrally molded with ceramic material. That is, the coupling member 11 is heat-resistant to the support plate 4-2, is strong, and is integrally formed with a ceramic material having a low coefficient of thermal expansion. Therefore, the relative position variation between the inspection regions 2 is extremely small. it can.

  As shown in FIG. 3 a, a schematic cross-sectional view of a probe card 1 having a plurality of inspection regions 2, wherein the support plate 4-2 constituting the support unit 4 is a slidable resin plate on the substrate 6. The substrate 6 is screwed up and down with a plurality of pan screws 8 through the resin plate 5. In addition, the support plate 4-2 in each inspection region 2 is integrally formed and coupled with the coupling member 11. Thereby, the relative position fluctuation between the inspection regions 2 can be extremely reduced. FIG. 3 b is a schematic cross-sectional view of another probe card 1 having a plurality of inspection regions 2, in order to maintain the planar shape of the support plate 4-2 on the back surface of the support plate 4-2. A reinforcing plate 7 having a shape similar to that of the plate 4-2 is coupled with a pan screw 8 in the vertical direction. Further, the fluororesin 5 which is an easily slidable resin plate is sandwiched between the support plate 4-2 and the reinforcement plate 7 so as not to be restrained by the thermal displacement of the reinforcement plate 7 in the horizontal direction. In addition, the support plate 4-2 in each inspection region 2 is integrally formed and coupled with the coupling member 11. Thereby, the relative position fluctuation between the inspection regions 2 can be extremely reduced. The effect on thermal deformation or thermal displacement under temperature control in the probe 3 group in each inspection region 2 is as described above, and the influence of thermal deformation or thermal displacement of the substrate 6 or the reinforcing plate 7 is minimized in each probe area. Can be limited. Therefore, the configuration of the present invention can be sufficiently applied to the probe card 1 having a plurality of inspection regions 2.

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

BRIEF DESCRIPTION OF THE DRAWINGS It is a probe card which is embodiment of this invention, Comprising: a is a typical top view, b is typical sectional drawing, c is the A section enlarged view of b. a is a sectional view of another embodiment in FIG. 1, and b is an enlarged view of a part A of FIG. It is a probe card which is another embodiment of the present invention, and has a plurality of inspection fields, a is a typical sectional view of a probe card, b is a typical sectional view of another probe card, c is a, It is a typical top view of the connecting member in b. It is a probe support unit in the conventional probe card, Comprising: a is typical sectional drawing, b is the A section enlarged view of a.

Explanation of symbols

1: Probe card 2: Inspection area 3: Probe 4: Support unit 4-1: Resin fixing part 4-2: Support plate 5: Fluorine resin plate 6: Substrate 7: Reinforcement plate 8: Pan screw 9: Metal washer 10: Fluororesin washer 11: Bonding member 12: Opening 13: High temperature epoxy resin

Claims (2)

A substrate in which a plurality of openings that are spaced apart from each other corresponding to the inspection region are opened, a reinforcing plate that is provided so as to cover the opening on the front surface side of the substrate, and a plurality that are provided on the back surface side of the substrate, A probe support unit held so as to be slidable with respect to the reinforcing plate through the opening; and a coupling member that integrally couples the plurality of support units at a predetermined interval. Probe card. The probe card of claim 1, wherein the coupling member, characterized in that it is a member that extends diagonally in the examination region of each support unit for integrally coupling said plurality of support units.

Images