Probe card

Abstract

To provide a probe card capable of more reliably abutting on an inspection object.SOLUTION: A probe card 10 includes: a flexible film 1 that is flexible while multiple bumps 12 are disposed on a first main surface 1a; multiple wires 11 that are disposed in the flexible film 1 and are connected to at least one of the bumps 12; and an elastic member 2 provided in a side of a second main surface 1b as a main surface in an opposite side of the first main surface 1a of the flexible film 1. The flexible film 1 has a cut region MA having a cut for dividing a segment for connecting the multiple bumps 12, and a main region PA other than the cut region MA. The elastic member 2 is provided in a position overlapping with the cut region MA of at least the flexible film 1 when seen from a direction that is orthogonal to the first main surface 1a of the flexible film 1, and is connected to the main region PA of the flexible film 1.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a probe card.

Background Art

[0002] A probe card used for inspecting electrical characteristics of semiconductor elements and the like is known.

[0003] Patent Document 1 discloses a probe card configured such that wirings and electrical inspection bumps are arranged on one surface of a flexible film, an elastic member abuts on the other surface, and a rigid body abuts on the other surface of the elastic member. According to this probe card, even when there are variations in the height direction in the electrodes or electrical inspection bumps provided on the semiconductor element to be inspected, the elastic member absorbs such variations in the height direction, and it is said that stable contact can be realized between the semiconductor element and the electrical inspection bumps.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the probe card described in Patent Document 1, when there are variations in the height direction in the electrodes or electrical inspection bumps provided on the semiconductor element to be inspected, when one of the plurality of electrical inspection bumps abuts on one electrode of the semiconductor element, there is a possibility that contact cannot be obtained between the electrical inspection bumps existing around and the electrodes of the semiconductor element.

[0006] FIG. 14 is a side view schematically showing a state in which the electrical inspection bumps 110a to 110c of the probe card 100 described in Patent Document 1 are brought into contact with the electrodes 210a to 210c of the semiconductor element 200 on the stage 220. As described above, the probe card 100 described in Patent Document 1 includes a flexible film 120 having electrical inspection bumps 110a to 110c disposed on one surface, an elastic member 130, and a rigid body 140. In the example shown in FIG. 14, among the plurality of electrical inspection bumps 110a to 110c provided on the probe card 100, the central electrical inspection bump 110b is assumed to have a higher height than the other electrical inspection bumps 110a and 110c.

[0007] When inspecting the semiconductor element 200, the probe card 100 and the semiconductor element 200 are relatively brought closer to each other, and the electrical inspection bumps 110a to 110c of the probe card 100 are brought into contact with the electrodes 210a to 210c of the semiconductor element 200. At this time, as shown in FIG. 14, when the central electrical inspection bump 110b having a higher height and the central electrode 210b of the semiconductor element 200 first come into contact, the flexible film 120 and the elastic member 130 are recessed at the contact position and the surrounding positions. As a result, between the electrical inspection bump 110a located around the central electrical inspection bump 110b and having a lower height than the electrical inspection bump 110b and the electrode 210a of the semiconductor element 200, and between the electrical inspection bump 110c and the electrode 210c of the semiconductor element 200, contact may not be made, and there is a possibility that the inspection cannot be performed.

[0008] Further, even if the electrical inspection bumps 110a to 110c and the electrodes 210a to 210c of the semiconductor element 200 are in contact with each other with difficulty, there are variations in the contact positions and loads, so it is difficult for the measurement results of the electrical characteristics in the inspection to be stable. In particular, when performing high-frequency measurement, since the influence of the contact position and load is large, the possibility of obtaining stable measurement results is low.

[0009] The present invention solves the above problems, and an object thereof is to provide a probe card capable of more reliably making contact with an object to be inspected.

Means for Solving the Problem

[0010] The probe card of the present invention includes a flexible film having flexibility and having a plurality of bumps arranged on a first main surface, a plurality of wirings arranged on the flexible film and connected to at least one of the bumps, an elastic member provided on a second main surface side, which is a main surface opposite to the first main surface of the flexible film, and the flexible film has a cut region in which a cut is made to divide a line segment connecting the plurality of bumps, and a main region other than the cut region, the elastic member is provided at a position overlapping at least the cut region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film, and is connected to the main region of the flexible film.

Advantages of the Invention

[0011] According to the probe card of the present invention, since the flexible film has a cut for dividing a line segment connecting the plurality of bumps, when inspecting an object to be inspected, the electrodes of the bumps and the object to be inspected come into contact. Even if the flexible film and the elastic member are recessed at the position of the contacting bump, it is possible to suppress the load from being transmitted to the adjacent bumps. Thereby, the contact between the bump and the electrode of the object to be inspected can be more surely made, and a more stable inspection result can be obtained.

Brief Description of the Drawings

[0012]

Figure 1

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Figure 10

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Figure 14

Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be shown and the features of the present invention will be specifically described.

[0014] <First Embodiment> FIG. 1(a) is a top view schematically showing the configuration of the probe card 10 in the first embodiment, (b) is a partially enlarged view of FIG. 1(a), and (c) is a cross-sectional view taken along the IC-IC line of FIG. 1(b). The probe card 10 in the present embodiment has a sheet-like shape as a whole.

[0015] The probe card 10 in the first embodiment includes a flexible film 1, an elastic member 2, and a plurality of wirings 11. The probe card 10 in this embodiment further includes a connector 3.

[0016] The flexible film 1 is a film having flexibility that can be bent or flexed, and a plurality of bumps 12 are arranged on the first main surface 1a. The flexible film 1 is made of, for example, polycarbonate, polyethersulfide, polyethylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, polyimide, polyamide, or liquid crystal polymer. The thickness of the flexible film 1 is, for example, 25 μm or more and 200 μm or less.

[0017] The wiring 11 is arranged on the flexible film 1 and is connected to at least one bump 12. More specifically, each of the plurality of wirings 11 is in close contact with the flexible film 1, one end is connected to the bump 12, and the other end is connected to the connector 3. In this embodiment, as shown in FIG. 1(a), the wirings 11 are arranged in a manner of extending from the connectors 3 provided on one end side and the other end side of the flexible film 1 toward the bump 12 arranged in the center. In particular, as shown in FIG. 1(b), the wiring 11 extending from the connector 3 provided on one end side of the flexible film 1 toward the bump 12 and the wiring 11 extending from the connector 3 provided on the other end side of the flexible film 1 toward the bump 12 are opposed to each other at the position where they are connected to the bump 12. In this embodiment, there are a plurality of pairs of wirings 11 that are opposed to each other at the position where they are connected to the bump 12. The wiring 11 is, for example, a signal line for transmitting signals.

[0018] The material of the wiring 11 is not particularly limited as long as it has conductivity, and for example, Cu can be used. The wiring 11 can be formed, for example, by thermocompression bonding of a foil material, printing, dry film formation such as sputtering, etc. Further, plating may be applied to the surface of the wiring 11. The plating can be, for example, a two-layer structure with Ni plating on the first layer and Au plating on the second layer. The width of the wiring 11 is, for example, 50 μm or more and 200 μm or less, and the thickness is, for example, 12.5 μm or more and 50 μm or less. The minimum distance between adjacent wirings 11 is, for example, 0.02 μm. The wiring 11 has flexibility to follow shape changes such as bending and flexing of the flexible film 1.

[0019] In addition, in FIGS. 1(a) to (c), a configuration is shown in which a plurality of wirings 11 are arranged on the first main surface 1a of the flexible film 1, but all or part of at least some of the wirings 11 may be arranged inside the flexible film 1.

[0020] The probe card 10 may include a ground conductor (not shown). For example, the ground conductor can be arranged on the first main surface 1a of the flexible film 1 and on the second main surface 1b which is the main surface opposite to the first main surface 1a. In that case, the ground conductors arranged on the first main surface 1a and the second main surface 1b can be electrically connected to each other via vias (not shown).

[0021] The bump 12 is a part that comes into contact with the electrodes of the object to be inspected during the inspection of the object to be inspected, and a plurality of bumps 12 are provided at positions corresponding to the positions of the plurality of electrodes provided on the object to be inspected. The object to be inspected is, for example, a semiconductor element, a high-frequency filter, or a high-frequency transmission line, etc. The material of the bump 12 is not particularly limited as long as it has conductivity, and for example, Cu, an alloy containing Cu as a main component, Ni, or an alloy containing Ni as a main component can be used. Plating may be applied to the surface of the bump 12. The hardness of the bump 12 is, for example, equivalent to or harder than the hardness of the electrodes of the object to be inspected.

[0022] The bump 12 in the present embodiment has a columnar shape. The diameter of the bump 12 when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1 is, for example, 50 μm or more and 200 μm or less, and the height is, for example, 50 μm or more and 200 μm or less. However, the shape of the bump 12 is not limited to a columnar shape, and may be a shape such as a quadrangular prism, a quadrangular pyramid, or a cone, or may be a shape in which two cylinders having different diameters are stacked so that their central axes coincide.

[0023] As shown in FIG. 1(b), the flexible film 1 has a cut region MA in which a cut 20 that divides a line segment connecting the plurality of bumps 12 is formed, and a main region PA other than the cut region MA. The cut region MA includes a belt portion 1X of the flexible film 1, which will be described later. In the present embodiment, the cut region MA is located at the center of the flexible film 1. By forming the cut 20 that divides the line segment connecting the plurality of bumps 12 in the flexible film 1, the plurality of bumps 12 can move independently in the plane direction of the flexible film 1.

[0024] In the present embodiment, as shown in FIGS. 1(b) and 2, when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1, cuts 20 are formed along three sides of the end of the wiring 11 on the side connected to the bump 12 so as to surround the end of the wiring 11. That is, the cuts 20 are formed not only between the wirings 11 adjacent in the width direction orthogonal to the extending direction of the wiring 11 but also between the wirings 11 facing each other in the extending direction of the wiring 11. By forming the cuts 20 in the flexible film 1 along three sides of the end of the wiring 11 on the side connected to the bump 12 so as to surround the end of the wiring 11, as shown in FIG. 2, a belt portion 1X of the flexible film 1 having a strip shape with three sides surrounded by the cuts 20 is formed. Since each of the belt portions 1X of the flexible film 1 can move independently from the belt portions 1X of the other flexible films 1 with the position connected to the main region PA as a fulcrum, the bumps 12 arranged on the belt portions 1X of the flexible film 1 can also move independently from the other bumps 12.

[0025] The length L1 of the notch 20 (see FIG. 1(b)) in the extending direction of the wiring 11 is, for example, 0.4 mm or more and 1.5 mm or less, and the width L2 of the notch 20 (see FIG. 2) is, for example, 0.01 mm or more and 0.05 mm or less. Further, in the width direction of the wiring 11, the distance L3 (see FIG. 2) between the end of the wiring 11 and the end of the notch 20 is, for example, 0 mm or more and 0.04 mm or less.

[0026] The connector 3 is for connecting to an external circuit when inspecting the electrical characteristics of the object to be inspected, and one end thereof is connected to the other end of the wiring 11 that is connected to at least one bump 12. By providing the probe card 10 with the connector 3, the connection between the probe card 10 and the external circuit becomes easy.

[0027] The elastic member 2 is provided on the second main surface 1b side of the flexible film 1 and at a position overlapping at least the cut region MA of the flexible film 1 when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1, and is connected to the main region PA on the second main surface 1b side of the flexible film 1. There is no particular restriction on the method of connecting the elastic member 2 and the main region PA of the flexible film 1. For example, they are connected by adhesion via an adhesive. The elastic member 2 is not connected to the cut region MA of the flexible film 1 and is in sliding contact with each other. In the present embodiment, a plurality of bumps 12 and elastic members 2 are arranged such that the center positions of the plurality of bumps 12 arranged on the first main surface 1a of the flexible film 1 coincide with the center positions of the elastic members 2.

[0028] There is no particular restriction on the material of the elastic member 2. For example, it is made of rubber such as urethane rubber, nitrile rubber, or silicone rubber. The size of the elastic member 2 when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1 is at least larger than the cut region MA of the flexible film 1. For example, it is the same as the size of the flexible film 1. However, the size of the elastic member 2 when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1 may be larger or smaller than the size of the flexible film 1.

[0029] There is no particular restriction on the thickness of the elastic member 2 which is the dimension in the direction orthogonal to the first main surface 1a of the flexible film 1. However, when the object to be inspected comes into contact with the bump 12, it is necessary to have a thickness that can support the bump 12 and the flexible film 1. Further, the elastic member 2 preferably has a thickness of 0.1 mm to 1 mm or more that can absorb such variations even if there are variations in the height direction in the electrodes of the object to be inspected or the bump 12. The spring constant of the elastic member 2 is, for example, 80 gf / mm or more and 400 gf / mm or less. The compression set of the elastic member 2 is preferably 10% or less. When the compression set of the elastic member 2 is 10% or less, the probe card 10 can be repeatedly used.

[0030] In the probe card 10 in the present embodiment, by providing a cut 20 in the flexible film 1 that divides a line segment connecting the plurality of bumps 12, even if a load is applied to one bump 12, it is possible to suppress the influence of the load on the surrounding bumps 12. Thereby, when an arbitrary bump 12 of the probe card 10 comes into contact with the electrode of the object to be inspected in order to inspect the electrical characteristics of the object to be inspected, it is possible to suppress the influence of the load applied to another bump 12 adjacent to the contacted bump 12. Further, since the elastic member 2 is not connected to the cut region MA of the flexible film 1 but is connected to the main region PA, even if the elastic member 2 is affected by the load within the cut region MA, it is possible to suppress the load from being transmitted to the adjacent bump 12. Further, since the elastic member 2 is connected to the main region PA of the flexible film 1, it is possible to suppress the displacement between the flexible film 1 and the elastic member 2.

[0031] FIG. 3 is a cross-sectional view schematically showing a state of inspecting the electrical characteristics of the object 30 to be inspected on the stage 32 using the probe card 10 in the present embodiment. In the example shown in FIG. 3, among the plurality of bumps 12a to 12c of the probe card 10, the central bump 12b is assumed to have a higher height than the other bumps 12a and 12b. Note that the inspection of the electrical characteristics of the object 30 to be inspected is an inspection for confirming energization or the like by passing an electric current through the electrodes 31a to 31c of the object 30 to be inspected. There is no particular limitation on the type of electrical characteristics to be inspected.

[0032] When inspecting the electrical characteristics of the object 30 to be inspected, the probe card 10 and the object 30 to be inspected are relatively brought closer to each other so that the plurality of bumps 12a to 12c of the probe card 10 and the plurality of electrodes 31a to 31c of the object 30 to be inspected are in contact with each other. As a result, first, the central bump 12b having the highest height comes into contact with the corresponding electrode 31b of the object 30 to be inspected. At this time, among the flexible films 1, the portion where the central bump 12 is disposed is pushed toward the elastic member 2. However, since the cut 20 is formed in the flexible film 1, the belt portion 1X of the flexible film 1 where the central bump 12 is disposed is pushed toward the elastic member 2. Thereby, it is possible to suppress the application of a load to the other bumps 12a and 12c adjacent to the central bump 12b, so that between the bump 12a adjacent to the central bump 12b and the corresponding electrode 31a of the object 30 to be inspected, and between the bump 12c and the corresponding electrode 31c of the object 30 to be inspected can be prevented from being non-contact. Thereby, the inspection of the electrical characteristics of the object 30 to be inspected can be surely performed.

[0033] When the inventors conducted an experiment to examine the influence of the load on the surrounding bumps 12 when one bump 12 came into contact with one electrode of the object to be inspected under the condition that the heights of the plurality of bumps 12 of the probe card 10 were equal, when the displacement of the bump 12 in contact with the electrode of the object to be inspected was 20 μm, the displacement of the adjacent bump 12 was 10 μm. On the other hand, when the same experiment was conducted using a flexible film without a cut, the displacement of the adjacent bump was 17 μm.

[0034] That is, by using the probe card 10 in this embodiment in which the notch 20 is formed in the flexible film 1, when the bump 12 comes into contact with the electrode of the object to be inspected, the influence of the load on the adjacent bump 12 can be reduced from 85% (17 / 20×100) to 50% (10 / 20×100).

[0035] <Second Embodiment> In the probe card 10A in the second embodiment, when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1, the elastic member 2 has a notch at a position corresponding to the position where the notch 20 of the flexible film 1 is formed. When viewed in the direction orthogonal to the first main surface 1a of the flexible film 1, the position corresponding to the position where the notch 20 of the flexible film 1 is formed means the same position as the position where the notch 20 of the flexible film 1 is formed or a position close to the position where the notch 20 of the flexible film 1 is formed.

[0036] FIG. 4(a) is a top view of a region of the elastic member 2 of the probe card 10A in the second embodiment at the same position as the region shown in FIG. 1(b), and (b) is a cross-sectional view taken along line IVB-IVB of (a). The cutting position along line IVB-IVB in FIG. 4(a) is the position where the notch 40 is formed. Here, an example in which the notch 40 is formed at the same position as the position where the notch 20 of the flexible film 1 is formed when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1 will be described. However, when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1, the position where the notch 20 of the flexible film 1 is formed and the position where the notch 40 is formed in the elastic member 2 do not necessarily exactly coincide.

[0037] The width of the cut 40 of the elastic member 2 may be the same as or different from the width L2 of the cut 20 of the flexible film 1. As an example, the width of the cut 40 of the elastic member 2 is the same as the width L2 of the cut 20 of the flexible film 1, for example, not less than 0.01 mm and not more than 0.05 mm. Also, the length of the cut 40 of the elastic member 2 may be the same as or different from the length L1 of the cut 20 of the flexible film 1. As an example, the length of the cut 40 of the elastic member 2 is not less than 0.4 mm and not more than 1.5 mm.

[0038] The depth of the cut 40 of the elastic member 2 may be the same as the thickness of the elastic member 2 or may be shallower than the thickness of the elastic member 2. In the present embodiment, as shown in FIG. 4(b), the depth V1 of the cut 40 of the elastic member 2 is shallower than the thickness V2 of the elastic member 2. For example, if the thickness V2 of the elastic member 2 is 0.5 mm, the depth V1 of the cut 40 is 0.2 mm.

[0039] By having the cut 40 at a position corresponding to the position where the cut 20 of the flexible film 1 is inserted in the elastic member 2, each of the plurality of bumps 12 is less likely to be affected by the load from other bumps 12. That is, when viewed in the direction orthogonal to the first main surface 1a of the flexible film 1, the strip portions 2X of the elastic member 2 at the positions overlapping the strip portion 1X of the flexible film 1 can each move independently of the strip portions 2X of the other elastic members 2. Therefore, the bumps 12 arranged at the positions overlapping the strip portions 2X of the elastic member 2 can also move more independently of the other bumps 12, and the influence of the load from the other bumps 12 is less likely to reach them.

[0040] In the experiment conducted by the inventor, by using the probe card 10A in the present embodiment in which the cut 40 is made in the elastic member 2, compared with the probe card 10 in the first embodiment in which the cut 40 is not provided in the elastic member 2, when the electrode of the object to be inspected comes into contact with the bump 12, it was confirmed that the influence of the load applied to the adjacent bump 12 was further reduced by 20%. That is, like the probe card 10A in the present embodiment, it is preferable that the elastic member 2 has a cut 40 at a position corresponding to the position where the cut 20 of the flexible film 1 is made when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1.

[0041] <Third Embodiment> FIG. 5 is a cross-sectional view of a main part of the probe card 10B in the third embodiment. The cutting position of the cross-sectional view in FIG. 5 is the same as the cutting position of the cross-sectional view in FIG. 1(c), and FIG. 5 shows a cross-section of the same region as FIG. 1(c).

[0042] The probe card 10B in the third embodiment further includes a fixing member 4 provided at a position overlapping at least a part of the main region PA of the flexible film 1 when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1 on the second main surface 1b side of the flexible film 1. The fixing member 4 is preferably connected to the flexible film 1. There is no particular restriction on the method of connecting the fixing member 4 and the flexible film 1, and for example, they are connected by adhesion via an adhesive.

[0043] In the present embodiment, the fixing member 4 has a frame-like shape surrounding the elastic member 2. The fixing member 4 is made of a material having a rigidity higher than that of at least the flexible film 1, such as metal, resin, or ceramics. By providing the probe card 10B with the fixing member 4, the strength of the probe card 10B can be improved. Further, since the fixing member 4 has a frame-like shape, the strength of the probe card 10B can be further improved.

[0044] Further, according to the probe card 10B in the third embodiment, on the second main surface 1b side of the flexible film 1, when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1, by further providing the fixing member 4 provided at a position overlapping at least a part of the main region PA of the flexible film 1, the main region PA of the flexible film 1 is more firmly fixed by the fixing member 4. Thereby, when the electrode of the object to be inspected comes into contact with the bump 12, it becomes possible to further suppress the influence of the load applied to the adjacent bump 12 via the main region PA of the flexible film 1, and the contact between the bump 12 and the electrode of the semiconductor element can be performed more reliably.

[0045] In the experiment conducted by the inventor, when the probe card 10B in the third embodiment was used, when the electrode of the object to be inspected came into contact with the bump 12, when the displacement of the contacted bump 12 was 20 μm, the displacement of the adjacent bump 12 was 3 μm. That is, although the influence of the load on the adjacent bump 12 was 50% when the probe card 10 in the first embodiment was used, by using the probe card 10B in the third embodiment, it can be reduced to 15%.

[0046] Therefore, it is preferable to further provide the fixing member 4 provided at a position overlapping at least a part of the main region PA of the flexible film 1 on the second main surface 1b side of the flexible film 1, like the probe card 10B in the present embodiment, when viewed in a direction orthogonal to the first main surface 1a of the flexible film 1.

[0047] <Fourth Embodiment> In the probe card 10B in the third embodiment, the fixing member 4 is provided on the second main surface 1b side of the flexible film 1.

[0048] On the other hand, the probe card 10C in the fourth embodiment further includes a pusher 5 for urging at least the cut region MA of the flexible film 1 from the second main surface 1b side, and the fixing member 4 is a part of the pusher 5 (see FIG. 6). The pusher 5 is used to press the flexible film 1 against the object to be inspected so that the bump 12 and the electrode of the object to be inspected come into contact with each other during the inspection of the object to be inspected.

[0049] FIG. 6(a) is a side view schematically showing the configuration of the probe card 10C in the fourth embodiment. The pusher 5 may have any shape and structure as long as it is for pressing the flexible film 1 against the object to be inspected. A recess 50 into which the elastic member 2 provided on the second main surface 1b side of the flexible film 1 is inserted is provided at the tip of the pusher 5, which is in contact with the flexible film 1.

[0050] During the inspection of the object to be inspected, the pusher 5 presses the probe card 10C against the object to be inspected so that the bump 12 and the electrode of the object to be inspected 30 come into contact with each other. Since the connector 3 is connected and fixed to, for example, an external connector of an external circuit, the flexible film 1 bends as shown in FIG. 6(b). Note that in FIGS. 6(a) and 6(b), the very small bumps 12 are omitted.

[0051] As shown in FIG. 6(b), the elastic member 2 of the probe card 10C is inserted into the recess 50 of the pusher 5, and the tip portion of the pusher 5 constitutes the fixing member 4. That is, the portion of the tip of the pusher 5 that contacts the second main surface 1b of the flexible film 1 and surrounds the elastic member 2 constitutes the fixing member 4.

[0052] Similar to the probe card 10B in the third embodiment, the probe card 10C in this embodiment includes the fixing member 4, so that when the electrode of the object to be inspected 30 comes into contact with the bump 12, the influence of the load applied to the adjacent bump 12 through the main region PA of the flexible film 1 can be further suppressed, and the contact between the bump 12 and the electrode of the object to be inspected 30 can be made more reliable.

[0053] <Fifth Embodiment> FIG. 7 is a partially enlarged view schematically showing the configuration of the main part of the probe card 10D in the fifth embodiment. In the partially enlarged view shown in FIG. 7, the cut region MA and its peripheral region are shown.

[0054] The probe card 10D in the fifth embodiment further includes a ground conductor 13 disposed on the first main surface 1a of the flexible film 1. The ground conductor 13 is spaced apart from the wiring 11 and is electrically insulated from each other. As will be described later, since the formation methods of the wiring 11 and the ground conductor 13 in the cut region MA and the main region PA are different, the minimum separation distance L4 between the wiring 11 and the ground conductor 13 in the cut region MA is shorter than the minimum separation distance L5 between the wiring 11 and the ground conductor 13 in the main region PA. For example, the minimum separation distance L4 between the wiring 11 and the ground conductor 13 in the cut region MA is at least 20 μm shorter than the minimum separation distance L5 between the wiring 11 and the ground conductor 13 in the main region PA.

[0055] The ground conductor 13 in the present embodiment is made of the same material as the wiring 11. The plurality of wirings 11 and the ground conductor 13 are provided on the same surface of the flexible film 1, more specifically, on the first main surface 1a, and constitute a so-called coplanar wiring structure.

[0056] The ground conductor 13 is preferably provided on both sides in the width direction of at least one of the plurality of wirings 11. In the example shown in FIG. 7, the ground conductors 13 are provided on both sides in the width direction of all four wirings 11. By providing the ground conductors 13 on both sides in the width direction orthogonal to the extending direction of the wiring 11, the influence of noise on the wiring 11 can be reduced.

[0057] In the example shown in FIG. 7, among the six bumps 12, four bumps 12 are electrically connected to the wiring 11, and the remaining two bumps 12 are electrically connected to the ground conductor 13. However, the bumps 12 electrically connected to the ground conductor 13 can be omitted.

[0058] FIG. 2 shows the width L2 of the notch 20 of the probe card 10 and the distance L3 between the end of the wiring 11 and the end of the notch 20 in the first embodiment. The width L2 of the notch 20 of the probe card 10D in this embodiment is, for example, 0.01 mm or more and 0.05 mm or less. Also, in the width direction of the wiring 11, the distance L3 between the end of the wiring 11 and the end of the notch 20 is, for example, 0 mm or more and 10 μm or less.

[0059] The characteristic impedance of the cut region MA of the flexible film 1 preferably matches or is close to the characteristic impedance of the main region PA. For example, by adjusting the width of the wiring 11 in the cut region MA and the width L2 of the notch 20, it is possible to bring the characteristic impedance of the cut region MA closer to the characteristic impedance of the main region PA. As an example, when the characteristic impedance of the main region PA of the flexible film 1 is 50 Ω, the wiring 11 and the ground conductor 13 are made of Cu, the thickness of the flexible film 1 is 50 μm, and the relative dielectric constant is 3.3, by setting the width of the wiring 11 in the cut region MA to about 155 μm and the width L2 of the notch 20 to about 25 μm, the characteristic impedance of the cut region MA can be made to substantially match the characteristic impedance of the main region PA.

[0060] The ground conductor 13 can be provided not only on the first main surface 1a of the flexible film 1 but also on a partial region of the second main surface 1b. In that case, it is preferable that the ground conductor 13 is not provided in the region of the second main surface 1b that overlaps the wiring 11 in the cut region MA in the direction orthogonal to the flexible film 1.

[0061] FIG. 8(a) is a partial cross-sectional view of a probe card 10D in which a ground conductor 13 is also provided in a main region PA of a second main surface 1b of the flexible film 1, and FIG. 8(b) is a partial plan view showing the arrangement position of the ground conductor 13 provided on the second main surface 1b side of the flexible film 1. In the examples shown in FIGS. 8(a) and 8(b), a ground conductor 13 is provided in the main region PA of the second main surface 1b of the flexible film 1, and no ground conductor 13 is provided in the cut region MA. Therefore, in the second main surface 1b, no ground conductor 13 is provided in the region overlapping the wiring 11 in the cut region MA in the direction orthogonal to the flexible film 1.

[0062] By providing the ground conductor 13 also in the main region PA of the second main surface 1b of the flexible film 1, the wiring 11 is surrounded by the ground conductor 13 provided on the first main surface 1a and the ground conductor 13 provided on the second main surface 1b, so that the influence of noise on the wiring 11 can be further reduced.

[0063] The ground conductor 13 provided on the first main surface 1a of the flexible film 1 and the ground conductor 13 provided on the second main surface 1b are preferably electrically connected to each other via vias (not shown). By electrically connecting the ground conductor 13 provided on the first main surface 1a and the ground conductor 13 provided on the second main surface 1b to each other via vias, the ground can be made more stable, and the influence of noise on the wiring 11 can be further reduced.

[0064] Here, since the ground conductor 13 has a higher rigidity than the flexible film 1, if the ground conductor 13 is provided in the region overlapping the wiring 11 in the cut region MA in the direction orthogonal to the flexible film 1, the belt portion 1X of the flexible film 1 described above may be less likely to move independently. However, by not providing the ground conductor 13 in the region overlapping the wiring 11 in the cut region MA in the direction orthogonal to the flexible film 1 on the second main surface 1b of the flexible film 1, the belt portion 1X of the flexible film 1 can move independently more easily.

[0065] FIG. 9 is a partially enlarged view schematically showing another configuration example of a main part of the probe card 10D in the fifth embodiment. In the example shown in FIG. 9, 13 bumps 12 are provided, four of which are electrically connected to the wiring 11, and the remaining nine are electrically connected to the ground conductor 13.

[0066] A method for manufacturing the probe card 10D in the fifth embodiment will be described.

[0067] First, a conductor 14 for forming a plurality of wirings 11 and ground conductors 13 is laminated on the first main surface 1a of the flexible film 1, and by patterning, the conductor 14 in the region for separating the wiring 11 and the ground conductor 13 in the main region PA is removed (see FIG. 10(a)). In FIG. 10(a), the hatched region is the region where the conductor 14 has been removed and the first main surface 1a of the flexible film 1 is visible. Further, a plurality of bumps 12 are formed on the conductor 14.

[0068] Note that the shape of the region where a part of the conductor 14 is removed by patterning is not limited to the shape shown in FIG. 10(a). For example, the distance between the wiring 11 and the ground conductor 13 may be gradually shortened as it approaches the cut region MA, or the end of the region where the conductor 14 has been removed may be an arc shape convex toward the cut region MA. Also, even in the region that will later become the cut region MA, a part of the conductor 14 may be removed as long as the wiring 11 and the ground conductor 13 are not adjacent to each other.

[0069] As described above, a conductor (ground conductor 13) may also be provided in a part of the region of the second main surface 1b of the flexible film 1.

[0070] Subsequently, cuts are made in the flexible film 1 and the conductor 14 in a manner that divides the line segments connecting the plurality of bumps 12. As a result, as shown in FIG. 10(b), the conductor 14 is separated into a plurality of wirings 11 and the ground conductor 13. In the top view shown in FIG. 10(b), the cut 20 made in the flexible film 1 and the cut made in the conductor 14 are at the same position. That is, when viewed in a direction orthogonal to the flexible film 1, the wiring 11 and the ground conductor 13 are separated along the cut 20 of the flexible film 1.

[0071] FIG. 11(a) is a partially enlarged top view schematically showing a state in which cuts are made in the flexible film 1 and the conductor 14 when, as the cut region MA is approached during patterning to remove a part of the conductor 14, the distance separating the wiring 11 and the ground conductor 13 gradually decreases. The partially enlarged view shown in FIG. 11(a) shows the same region as the partially enlarged view shown in the lower right of FIG. 7.

[0072] The method of making the cuts is arbitrary, and for example, it can be performed by methods such as cutting with a cutting blade, cutting using a drill, or cutting with a laser. The conditions for cutting with a laser can be, for example, a frequency of 200 kHz, an energy amount of 27 μJ, a scan number of 40 times, and a processing speed of 500 mm / sec. Depending on the processing accuracy and the like, the cut 20 may penetrate into a part of the region where a part of the conductor 14 has been removed by the aforementioned patterning. FIG. 11(b) is a partially enlarged view schematically showing a state in which the cut 20 has penetrated into a part of the region where a part of the conductor 14 has been removed by patterning with respect to the partially enlarged view shown in FIG. 11(a).

[0073] As described above, the wiring 11 and the ground conductor 13 in the main region PA of the flexible film 1 are formed by patterning, while the wiring 11 and the ground conductor 13 in the cut region MA are formed by making cuts in the conductor 14. In the method of forming the wiring 11 and the ground conductor 13 by making cuts, the separation distance between the wiring 11 and the ground conductor 13 can be shortened easily and with high precision as compared with the method of forming by patterning.

[0074] As shown in FIG. 12, the cross sections of the flexible film 1 and the wiring 11 exposed by making cuts may not be parallel to the plane orthogonal to the flexible film 1 but may be inclined. Similarly, the cross section of the ground conductor 13 exposed by making cuts may not be parallel to the plane orthogonal to the flexible film 1 but may be inclined.

[0075] Finally, the elastic member 2 is disposed on the second main surface 1b side of the flexible film 1. By the above-described steps, the probe card 10D in the fifth embodiment is manufactured.

[0076] Here, in the conventional method of forming a plurality of wirings 11 and ground conductors 13 by patterning (see FIG. 13(b)), it is difficult to shorten the separation distance between the wiring 11 and the ground conductor 13 as compared with the method of forming a plurality of wirings 11 and ground conductors 13 by the cuts of the conductor 14 described above. For this reason, when the intervals between a plurality of bumps 12 are narrow, if a plurality of wirings 11 and ground conductors 13 are formed by patterning to achieve impedance matching between the main region PA and the cut region MA, it becomes difficult due to accuracy reasons.

[0077] Further, when a cut is made in the flexible film 1 in which the wiring 11 and the ground conductor 13 are formed on the first main surface 1a by patterning and the ground conductor is disposed over the entire second main surface 1b, the ground conductor 13 disposed on the second main surface 1b is disconnected by the cut (see FIG. 13(c)). In this case, a potential difference occurs between the ground conductors 13 adjacent to each other with the cut therebetween, resulting in capacitive coupling and possibly generating unnecessary resonance. In particular, when a high-frequency signal is transmitted through the wiring 11, the characteristics as a transmission line may deteriorate.

[0078] However, as described above, according to the method of forming the plurality of wirings 11 and the ground conductor 13 by making a cut in one conductor 14, even when the intervals between the plurality of bumps 12 are narrow, the plurality of wirings 11 and the ground conductor 13 can be easily and accurately formed (see FIG. 13(a)). Further, by not disposing the ground conductor 13 on the second main surface 1b of the flexible film 1, it is possible to avoid deterioration of the characteristics of the transmission line due to the disconnection of the ground conductor 13 described above. Similarly, even when the ground conductor 13 is not provided in the region overlapping the wiring 11 in the cut region MA in the direction orthogonal to the flexible film 1 in the second main surface 1b of the flexible film 1, it is possible to avoid deterioration of the characteristics of the transmission line due to the disconnection of the ground conductor 13 described above.

[0079] The present invention is not limited to the above-described embodiments, and various applications and modifications can be made within the scope of the present invention. For example, the characteristic configurations in the respective embodiments can be appropriately combined.

[0080] In the probe card 10D in the fifth embodiment, the plurality of wirings 11 and the ground conductor 13 are formed by making a cut in the conductor 14. However, for example, by making a cut in the conductor 14, a plurality of wirings 11 and another wiring can be formed, or a plurality of wirings 11 and terminals can be formed.

[0081] The probe card in the present application is as follows. <1>. A flexible film having flexibility and having a plurality of bumps disposed on a first main surface, a plurality of wirings disposed on the flexible film and connected to at least one of the bumps, and an elastic member provided on a second main surface side which is a main surface opposite to the first main surface of the flexible film, comprising: The flexible film has a cut region in which a cut is made to divide a line segment connecting the plurality of bumps, and a main region other than the cut region, The elastic member is provided at a position overlapping at least the cut region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film, and is connected to the main region of the flexible film. A probe card characterized by that. <2>. The elastic member has a cut at a position corresponding to a position where the cut of the flexible film is made when viewed in a direction orthogonal to the first main surface of the flexible film. The probe card according to <1>. <3>. The depth of the cut of the elastic member is shallower than the thickness of the elastic member in a direction orthogonal to the first main surface of the flexible film. The probe card according to <2>. <4>. On the second main surface side of the flexible film, a fixing member disposed at a position overlapping at least a part of the main region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film is further provided. The probe card according to any one of <1> to <3>. <5>. The fixing member has a frame-like shape surrounding the elastic member. The probe card according to <4>. <6>. Further comprising a pusher for urging at least the cut region of the flexible film from the second main surface side, The fixing member is a part of the pusher. The probe card according to <4> or <5>. <7>. Further comprising a ground conductor disposed on the first major surface of the flexible film, The minimum separation distance between the wiring and the ground conductor in the cut region is shorter than the minimum separation distance between the wiring and the ground conductor in the main region, and the probe card according to any one of <1> to <6>. <8>. The minimum separation distance between the wiring and the ground conductor in the cut region is 20 μm or more shorter than the minimum separation distance between the wiring and the ground conductor in the main region, and the probe card according to <7>. <9>. The ground conductor is provided on both sides in the width direction of at least one of the plurality of wirings, and the probe card according to <7> or <8>. <10>. The ground conductor is also provided in at least a partial region of the second major surface of the flexible film, but is not provided in a region overlapping the wiring in the cut region in a direction orthogonal to the flexible film, and the probe card according to any one of <7> to <9>. <11>. Further comprising a connector connected to the other end of the wiring having one end connected to at least one of the bumps, and the probe card according to any one of <1> to <10>.

Description of Reference Numerals

[0082] 1 Flexible film 1a First major surface of the flexible film 1b Second major surface of the flexible film 1X Band portion of the flexible film 2 Elastic member 2X Band portion of the elastic member 3 Connector 4 Fixing member 5 Pusher 10, 10A, 10B, 10C, 10D Probe card 11 Wiring 12, 12a, 12b, 12c Bump 13 Ground conductor 14 Conductor 20 Cut of Flexible Film 30 Object to be Inspected 31a, 31b, 31c Electrodes 40 Cut of Elastic Member 50 Recess of Pusher MA Cut Region PA Main Region

Claims

1. A flexible film having flexibility and having a plurality of bumps disposed on a first main surface, a plurality of wirings disposed on the flexible film and connected to at least one of the bumps, and an elastic member provided on a second main surface side which is a main surface opposite to the first main surface of the flexible film, and comprising: the flexible film has a cut region in which a cut is made to divide a line segment connecting the plurality of bumps, and a main region other than the cut region, the elastic member is provided at a position overlapping at least the cut region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film, and is connected to the main region of the flexible film, and is not connected to the cut region of the flexible film and is slidably in contact with the cut region, a probe card characterized by that.

2. The elastic member has a cut at a position corresponding to a position where the cut of the flexible film is made when viewed in a direction orthogonal to the first main surface of the flexible film, the probe card according to claim 1, characterized by that.

3. The depth of the cut of the elastic member is shallower than the thickness of the elastic member in a direction orthogonal to the first main surface of the flexible film, the probe card according to claim 2, characterized by that.

4. On the second main surface side of the flexible film, further comprising a fixing member disposed at a position overlapping at least a part of the main region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film, the probe card according to claim 1, characterized by that.

5. The fixing member has a frame-like shape surrounding the elastic member, the probe card according to claim 4, characterized by that.

6. Further comprising a pusher for biasing at least the cut region of the flexible film from the second main surface side, the fixing member is a part of the pusher, the probe card according to claim 4, characterized by that.

7. A recess into which the elastic member is inserted is provided in a portion of the pusher that contacts the flexible film, the probe card according to claim 6, characterized by that.

8. A flexible film having flexibility and having a plurality of bumps disposed on a first main surface, A plurality of wirings disposed on the flexible film and connected to at least one of the bumps; An elastic member provided on a second main surface side, which is a main surface opposite to the first main surface of the flexible film; The flexible film has a cut region in which a cut is made to divide a line segment connecting the plurality of bumps, and a main region other than the cut region; The elastic member is provided at a position overlapping at least the cut region of the flexible film when viewed in a direction orthogonal to the first main surface of the flexible film, and is connected to the main region of the flexible film; The flexible film further includes a ground conductor disposed on the first main surface of the flexible film; The probe card is characterized in that a minimum separation distance between the wiring and the ground conductor in the cut region is shorter than a minimum separation distance between the wiring and the ground conductor in the main region.

9. The probe card according to claim 8, wherein a minimum separation distance between the wiring and the ground conductor in the cut region is 20 μm or more shorter than a minimum separation distance between the wiring and the ground conductor in the main region.

10. The probe card according to claim 8, wherein the ground conductor is provided on both sides in the width direction of at least one of the plurality of wirings.

11. The probe card according to claim 8, wherein the ground conductor is also provided in at least a partial region of the second main surface of the flexible film, but is not provided in a region overlapping the wiring in the cut region in a direction orthogonal to the flexible film.

12. The probe card according to any one of claims 1 to 11, further comprising a connector connected to the other end of the wiring, one end of which is connected to at least one of the bumps.

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