JP4159495B2 - Probe card and semiconductor test equipment - Google Patents

Description

The present invention relates to a probe card and a semiconductor test apparatus , and more particularly to a probe card suitably used as a jig and a semiconductor test apparatus using the probe card in testing electrical characteristics of a semiconductor device .

  The probe card is used as a jig for measuring the electrical characteristics of the semiconductor device during the manufacturing process of the semiconductor device or at the time of completion test. Patent Document 1 describes a membrane-type probe card in which a bump-structured probe terminal is supported by a flexible (elastic) membrane ring. FIG. 3 shows an example of a conventional probe card adopting the membrane method (bump sheet method) described in Patent Document 1. The probe card 30 includes a membrane ring 31, a flexible sheet 32 that supports the membrane ring 31, and a flexible substrate 33 that supports the flexible sheet 32.

  A substantially hemispherical bump 34 is formed on the surface of the membrane ring 31, and the bump 34 is supported by a plug member 35 that penetrates the membrane ring 31. In the flexible sheet 32, a conductive member 36 having anisotropic conductivity is disposed immediately below the plug member 35. The flexible substrate 33 is configured as a polyimide substrate having a wiring pattern formed therein. The internal wiring pattern of the flexible substrate 33 is connected to an external terminal of a semiconductor test apparatus (not shown). The bumps 34 constituting the probe terminals are pressed by the electrode pads 41 of the semiconductor device 40 to be measured, and electrical conduction between the two becomes possible.

  The probe card 30 described in Patent Document 1 is composed of a three-layer ring of a flexible membrane, a sheet material, and a substrate, so that the probe terminal 34 and the electrode pad 41 of the semiconductor device 40 are provided. Even if there are variations in the height direction, good electrical contact is made possible by applying a uniform pressing force to a large number of bumps 24. Moreover, since each member 31, 32, 33 can be disassembled, it is said that the defect existing in the probe card and the repair of the failure are easy. In Patent Document 2, as an improved invention of Patent Document 1, the bumps formed on the upper surface of the first membrane and the bumps formed on the lower surface of the second membrane are shifted in the lateral direction. Describes a configuration in which variations in height of bumps and electrode pads are absorbed by twisting of the membrane.

  By the way, in the probe card, there is a problem that contact failure due to increase in contact resistance between the probe terminal and the electrode pad of the semiconductor device cannot be ignored. Such poor contact due to an increase in contact resistance is generally caused by a natural oxide film formed on the surface of the electrode pad, adhesion of foreign matter on the surface of the probe terminal due to repeated use of the probe terminal, and the like. In the probe cards described in Patent Documents 1 and 2, there is no description regarding this problem.

Patent Document 3 describes a probe card that solves the problem of poor contact with a probe card having rigidity different from that of a membrane probe card. In the probe card described in this publication, an elastic body having a special shape is disposed between the support substrate of the probe card and the probe card. When a pressing force between the probe terminal and the electrode pad is applied from the probe support substrate, the elastic body disposed between the probe support substrate and the probe card moves the probe card in the lateral direction, thereby the probe The terminal moves laterally on the electrode pad, so that the natural oxide film on the electrode pad and the foreign matter on the surface of the probe terminal can be scraped away.
JP 2000-49201 A (FIG. 7) Japanese Patent Application Laid-Open No. 11-118831 (FIG. 3) JP-A-7-37943 (FIG. 1)

  The probe card described in Patent Document 3 obtains the lateral movement force of the probe terminal by the action of an elastic body having a special shape. However, since the probe card itself is rigid, unlike the membrane type probe card, a uniform pressing force is not applied to the electrode pad of the semiconductor device, and a good electrical connection is provided between the electrode pad and the probe terminal. Contact may not be obtained.

  In view of the above, the present invention adopts a membrane system to obtain good electrical contact on the contact surface between the electrode pad and the probe terminal, and a natural oxide film or probe terminal generated on the electrode pad. It is an object of the present invention to provide a probe card that enables stable measurement of the electrical characteristics of a semiconductor device because good electrical contact is not impaired by foreign matters adhering to the semiconductor device.

  In order to achieve the above object, a probe card of the present invention supports a first insulating film made of an elastic material, a bump body disposed on the surface of the first insulating film, and the bump body. A probe terminal formed of a bump base that penetrates the first insulating film; and a support member that supports the first insulating film and the probe terminal and includes a wiring pattern that is electrically connected to the bump base. In the probe card provided, the bump base part supports a part of the bottom surface of the bump body, and the other part of the bottom surface of the bump body is supported by the first insulating film. To do.

  According to the probe card of the present invention, when the bump main body of the probe terminal is pressed against the electrode pad of the semiconductor device, the part not supported by the bump base on the bottom surface of the bump main body turns around the boundary with the supported part. As a result, the bump body tilts and a scrub phenomenon occurs between the electrode pad and the bump body. As a result, the natural oxide film and foreign matter that obstruct the contact between the electrode pad and the bump body are removed by rubbing, and good electrical contact is obtained between the two.

  In the probe card according to a preferred aspect of the present invention, the support member supports the first insulating film and penetrates through the second insulating film made of an elastic material, the second insulating film, and the second insulating film. A conductive member that has a higher rigidity than the insulating film and supports the bottom surface of the probe base, and the wiring pattern that is electrically connected to the bump base via the conductive member, A second insulating film and a substrate supporting the conductive member. In this case, the conductive member having high rigidity supports the bump base, and the second insulating film is elastically deformed together with the elastic deformation of the first insulating film, thereby assisting in turning the probe terminal. Generate an effective scrub phenomenon.

  It is also a preferred aspect of the present invention that half or less of the bottom surface of the bump body is supported by the bump base. In this case, the probe terminal can be turned more reliably.

  Hereinafter, the present invention will be further described based on exemplary embodiments of the present invention with reference to the accompanying drawings. FIG. 1 shows a cross section of a probe card according to an embodiment of the present invention. In the probe card 10, a first membrane 12 made of an elastic material having a plurality of bumps 11 disposed on the surface and a plug 13 made of rubber having anisotropic conductivity are flexible corresponding to the base of the bumps 11. It has the 2nd membrane 14 embedded in the insulator material, and the board | substrate 15 made from the glass epoxy resin which supported the 2nd membrane 14 and by which the wiring pattern was formed in the inside. In the probe card 10, the top of the bump 11 is pressed against the electrode pad 21 of the wafer 20 of the semiconductor device, receives an electrical signal from the electrode pad 21, and passes through the wiring pattern from the bump 11 to a semiconductor test device (not shown). Give an electrical signal.

  The first membrane 12 is configured as a sheet-like member having elasticity such as silicone rubber, and a large number of bumps 11 constituting probe terminals are arranged in an array on the surface. FIG. 2 shows an enlarged detailed structure of the bump 11. The bump 11 includes a bump body 11A that protrudes from the surface portion of the first membrane 12 and a plug-like bump base portion 11B that penetrates the first membrane 12. The bump body 11A has a substantially cylindrical shape in which the vicinity of the top is formed in a hemispherical shape, and the diameter of the cylinder is, for example, 40 μm. The bump base portion 11B has a cylindrical shape that is eccentrically arranged with respect to the bump main body 11A, and has a diameter of about 30 μm. The distance between the centers of the bump main body 11A and the bump base 11B is, for example, 18 μm. That is, the center of the bump main body 11A protrudes somewhat toward the first membrane 12 from the edge of the bump base 11B, and half or less of the bottom surface of the bump main body 11A is supported by the bump base 11B.

  The bump base portion 11B is formed by injecting a conductive material such as a metal such as Cu or Al into a hole having a diameter of 30 μm formed in the sheet 12 made of silicone rubber. The thickness of the bump base 111 </ b> B is substantially the same as the thickness of the first membrane 12. The bump main body 11A is formed on the surface of the first membrane 12 and the bump base 11B by a Cu or Al thick film printing technique.

  Returning to FIG. 1, the second membrane 14 is formed by embedding a plug 13 made of anisotropic conductive rubber in an elastic sheet material such as silicone rubber. Since the hardness of the anisotropic conductive rubber is sufficiently larger than the hardness of the silicone rubber, the plug 13 effectively supports the bottom portion of the bump base portion 11B. On the other hand, since the silicone rubber has a small hardness, the second membrane 14 is deformed according to the deformation of the first membrane 12.

  The substrate 15 is made of a glass epoxy resin material, and has a plurality of rigid insulating layers and a plurality of wiring patterns sandwiched between these insulating layers. The uppermost wiring pattern is electrically connected to each anisotropic conductive rubber plug 13 disposed in the second membrane 14 through a through-hole, and the lowermost wiring pattern is not shown formed on the bottom surface. The electrode pad is connected to an external terminal of a semiconductor test apparatus (not shown).

  In the probe card 10 having the above-described configuration, the bump main body 11A constituting the probe terminal is pressed against the corresponding electrode pad 21 of the wafer 20 by the chuck stage on which the wafer 20 is mounted during a test such as a wafer stage of the semiconductor device. When an appropriate pressing force is applied from the wafer 20 by overdrive, the bump body 11A is pressed by the electrode pad 21 and has a bottom surface portion supported by the anisotropic conductive plug 13 via the bump base portion 11B and has elasticity. Due to the different support force between the bottom surface portion supported by the silicone rubber 14, as shown in FIG. 1, the bottom surface portion tilts toward the silicone rubber 14 with the boundary line of both bottom surface portions as a fulcrum. For this reason, a scrubbing action occurs in the lateral direction between the bump main body 11A and the electrode pad 21, both surfaces are polished by rubbing, and the natural oxide film and foreign matter on the surface are removed. As a result, good electrical contact can be obtained, and highly reliable electrical characteristics can be measured.

  Although the present invention has been described based on the preferred embodiment, the probe card of the present invention is not limited to the configuration of the above embodiment, and various modifications and changes can be made from the configuration of the above embodiment. Those applied are also included in the scope of the present invention.

Sectional drawing of the probe card which concerns on one example of embodiment of this invention. Sectional drawing which expands and shows the probe terminal part of the probe card of FIG. Sectional drawing of the conventional membrane-type probe card.

Explanation of symbols

10: Probe card 11: Bump (probe terminal)
11A: Bump body 11B: Bump base 12: First membrane 13: Anisotropic conductive rubber plug 14: Second membrane 15: Glass epoxy resin substrate 20: Measurement target wafer 21: Electrode pad

Claims (13)

A probe card used for electrical property testing of a wafer to be measured,
The probe card is
A first insulating film made of an elastic material;
A probe terminal provided on the main surface of the probe card , comprising: a bump main body disposed on the surface of the first insulating film; and a bump base that supports the bump main body and penetrates the first insulating film. and,
A support member for supporting the first insulating film and the probe terminal and having a wiring pattern electrically connected to the bump base portion inside;
With
The bump base part supports a part of the bottom surface of the bump body, and the other part of the bottom surface of the bump body is supported by the first insulating film,
When performing the test contacted the electrode pads of the measurement target wafer and the probe pins, Ru good the pressing force from the measurement target wafer, a bottom portion supported by the support member through the bump base portion a probe card by different supporting force between the bottom portion supported on said first insulating film, wherein the probe terminal, and wherein the inclined with respect to the main surface of the probe card.   The probe card according to claim 1, wherein the probe terminal is positioned between a main surface of the probe card and an electrode pad of the measurement target wafer when performing the test.   The probe card according to claim 1, wherein the measurement target wafer is a wafer of a semiconductor device. A probe card used to perform electrical characteristic testing of the semiconductor device in a semiconductor test apparatus by contacting a probe terminal provided on the main surface of the probe card and an electrode pad of the semiconductor device,
The probe card is
A first insulating film made of an elastic material;
A bump body disposed on the surface of the first insulating film, and a probe terminal comprising a bump base that supports the bump body and penetrates the first insulating film;
A support member for supporting the first insulating film and the probe terminal and having a wiring pattern electrically connected to the bump base portion inside;
With
The bump base part supports a part of the bottom surface of the bump body, and the other part of the bottom surface of the bump body is supported by the first insulating film,
Upon the test of the semiconductor device, between the Ru good the pressing force from the semiconductor device, the bottom portion supported on said first insulating film and the bottom surface portion supported by the support member through the bump base portion a probe card by different supporting force, the probe terminal, and wherein the inclined with respect to the main surface of the probe card.   The probe card according to claim 4, wherein the probe terminal is located between a main surface of the probe card and an electrode pad of the semiconductor device when performing the test.   The probe card according to claim 1, wherein the tilting operation is a horizontal scrubbing operation that occurs between the probe terminal and the electrode pad. The first insulating film has elasticity, and the wiring pattern is stiffer than the insulating film, the probe card according to any one of claims 1 to 6. The first insulating layer is composed of silicone rubber, the wiring pattern is composed of anisotropic conductive rubber, the probe card according to any one of claims 1 to 7. The probe according to any one of claims 1 to 8 , wherein the scrub is generated by different support forces between a bottom surface portion supported by the first insulating film and a bottom surface portion supported by the wiring pattern. card. The supporting member supports the first insulating film and penetrates through the second insulating film made of an elastic material and has a higher rigidity than the second insulating film. A conductive member that supports the bottom surface of the probe base, and the wiring pattern that is electrically connected to the bump base via the conductive member, and the second insulating film and the conductive member and a substrate for supporting the probe card according to any one of claims 1 to 6. The probe card according to claim 10 , wherein the second insulating film is made of silicone rubber. The bump main body of the bottom surface substantially half below is supported by the bump base portion, the probe card according to any one of claims 1 to 11. A semiconductor test apparatus for measuring by contacting a probe terminal of a probe card and an electrode pad of a semiconductor device,
The semiconductor test apparatus, characterized in that using the probe card according to any one of claims 1 to 12.

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