JP2005291722A - Probe unit and method of manufacturing probe unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe unit and its manufacturing method capable of surely checking electric characteristics of an electronic device wherein a plurality of pipes are arranged at narrow pitches. <P>SOLUTION: A wiring film 20 divided into probes 22 and leads 24 is attached to a base 10. Four projecting edges 28 of an opening 26 formed on a center of each probe 22 are raised from a surface of the base 10 to define a contact part kept into contact with a bump of a test body. By forming the probes 22 by the wiring film 20, the plurality of probes 22 can be arranged on the base 10 at the narrow pitches. Further as the contact part is formed by raising four projecting edges 28, the contact part and the bump of the test body can be kept into point-contact with each other. Further as four projecting edges 28 are formed on each opening 26, four projecting edges 28 can be corresponded to each bump. The plurality of bumps are simultaneously electrically brought into contact with the wiring film 20 without fail by making four projecting edges 28 be corresponded to each bump. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a probe unit for inspecting electrical characteristics of an electronic device such as a semiconductor integrated circuit and a liquid crystal panel, and a method of manufacturing the probe unit.

  2. Description of the Related Art Conventionally, a probe unit is known in which a large number of thin-film probes formed by photolithography are arranged on a substrate at a narrow pitch, and the tips of the probes protrude from the edge of the substrate in a comb shape. Such a probe unit has been developed in response to the narrowing of the electrode pitch of an electronic device. Such a probe unit is suitable for inspection of an electronic device having a flat surface of each electrode because the tips of the probes (hereinafter referred to as comb-shaped thin film probes) are linearly aligned. At the time of inspection, a comb-like thin film probe is brought into contact with each electrode of the specimen one by one.

  Incidentally, in recent years, WL-CSP (Wafer Level-Chip Size Package) has been actively commercialized. Some electrodes of small electronic devices such as WL-CSP are bumps in which solder or the like is raised in a plateau or hump shape. However, since the bump surface is raised and the raised shape is not uniform, the linearly aligned tips of the comb-like thin film probe are simultaneously and reliably brought into contact with a plurality of bumps arranged on the surface of the package. It is difficult.

  As a probe capable of obtaining reliable contact with a plurality of bumps, a rod-like probe having a tip portion in which a plurality of protrusions are connected in a ring like a crown is known. Such a probe is formed separately from the substrate and then fixed to the substrate. Therefore, it is difficult to arrange such probes on the substrate at a narrow pitch according to the pitch of the bumps.

Patent Documents 1 and 2 disclose a multipoint connection sheet suitable for inspection of WL-CSP in which bumps are arranged at a narrow pitch, and a manufacturing method thereof.
However, the multipoint connection sheet disclosed in Patent Documents 1 and 2 includes a cylindrical probe that requires a complicated manufacturing process. Further, when a spherical bump is brought into contact with the inside of the end portion of the cylindrical probe, the bump and the probe come into contact with each other in a ring shape, so that there is a problem that the contact pressure between the bump and the probe becomes lower than in the case of point contact.
JP 2001-74806 A JP 2001-74807 A

The present invention was created to solve these problems, and an object thereof is to provide a probe unit capable of reliably inspecting the electrical characteristics of an electronic device in which a plurality of bumps are arranged at a narrow pitch. To do.
It is another object of the present invention to provide a simple manufacturing method of a probe unit that can reliably inspect the electrical characteristics of an electronic device in which a plurality of bumps are arranged at a narrow pitch.

  In order to achieve the first object, a probe unit according to the present invention includes a substrate, and a wiring film having a plurality of openings with meandering contours and formed on the surface of the substrate, and the wiring film The plurality of convex edges of each of the openings are raised from the surface of the substrate to form a contact portion that contacts a bump of the specimen. By forming the contact portion with a wiring film formed on the surface of the substrate, a plurality of contact portions can be arranged on the substrate with a narrow pitch. By forming the contact portion by raising the convex edge of the wiring film, the contact portion and the bump of the specimen can be brought into point contact. In addition, when the plurality of convex edges are formed in the wiring film for each opening by meandering the outline of the opening formed in the wiring film, the plurality of convex edges can correspond to each bump. By making a plurality of convex edges correspond to each bump, the plurality of bumps can be electrically connected to the wiring film reliably at the same time. Therefore, according to the probe unit of the present invention, the electrical characteristics of an electronic device in which a plurality of bumps are arranged at a narrow pitch can be reliably inspected.

  In order to achieve the second object, a method for manufacturing a probe unit according to the present invention includes a step of forming a wiring film having a plurality of openings having meandering contours on a surface of a substrate, and the vicinity of each opening of the substrate. And forming a through hole, and pushing up a plurality of convex edges of each opening of the wiring film from the through hole, and forming the convex edges into contact portions that contact the bumps of the specimen. It is characterized by that. The process of forming a plurality of openings whose contours meander in the wiring film formed on the surface of the substrate is simple. The process of removing the vicinity of each opening of the substrate and forming the through hole is also simple. The process of pushing up the plurality of convex edges of each opening of the wiring film from the through hole is also simple. Therefore, according to the manufacturing method according to the present invention, a probe unit capable of reliably inspecting the electrical characteristics of an electronic device in which a plurality of bumps are arranged at a narrow pitch can be manufactured in a simple process.

Embodiments of the present invention will be described below with reference to the drawings.
First, a probe unit according to an embodiment of the present invention will be described. FIG. 1 is a plan view showing the probe unit 1. 2 is a cross-sectional view taken along line AA in FIG.
As shown in FIGS. 1 and 2, the probe unit 1 has a wiring film 20 divided into probes 22 and leads 24 attached on a substrate 10 with an adhesive 30. For the wiring film 20, for example, a metal such as a nickel alloy such as Ni, Ni—W, or NiFe is used. A plurality of probes 22 are arranged on the substrate 10, and leads 24 are provided so as to extend from the probes 22. Each probe 22 has an opening 26 having a serpentine outline and a substantially cruciform shape, and four convex edges 28 of the opening 26 are raised from the surface of the substrate 10, so that each probe 22 is configured like a crown. The four convex edges 28 of the opening 26 form contact portions that contact the bumps of the specimen. As for the size of the opening 26, for example, the minimum width a at the upper end is about 0.2 mm, and the diameter b at the lower end is about 0.6 mm. The height of the convex edge 28 with respect to the surface of the lead 24 is, for example, about 0.5 mm. The substrate 10 has a cylindrical through-hole 12 below the opening 26.

Next, a continuity test method using the probe unit 1 will be described. FIG. 3 is a cross-sectional view showing a continuity test method.
First, as shown in FIG. 3A, the probe unit 1 is arranged so that each probe 22 faces each bump 40 of the specimen 4. Thereafter, as shown in FIG. 3B, the probe unit 1 is pressed against the specimen 4, and the bumps 40 and the bumps 40 are brought into contact with each other so that the bumps 40 are sandwiched between the bumps 28 of the openings 26 of the probe 22. Then, a continuity test is performed between the wiring film 20 and the bump 40. At this time, the convex edge 28 bends in accordance with the curved surface shape of the bump 40, so that the bump 40 is firmly sandwiched, and can be reliably brought into contact with the bump 40.

  According to the present embodiment, since the wiring film 20 can be formed on the surface of the substrate 10 using a conventional thin film manufacturing technique, a plurality of probes 22 formed of the wiring film 20 are formed on the substrate 10 with a narrow pitch. Can be arranged. Further, the contact portion and the bump 40 can be brought into four-point contact by meandering the outline of the opening 26 of the probe 22 and forming a contact portion corresponding to one bump 40 with the four raised protrusions 28. . By arranging a plurality of probes 22 having contact portions in four-point contact with the bumps 40 on the substrate 10, the plurality of bumps 40 can be reliably and simultaneously connected to the wiring film 20 without reducing the contact pressure. Therefore, according to the probe unit 1 of the present embodiment, it is possible to reliably inspect the electrical characteristics of an electronic device having a plurality of bumps arranged at a narrow pitch. Furthermore, the probe unit 1 of this embodiment can be used for burn-in of an electronic device.

The number of the convex edges 28 is not limited to four, and the number of the convex edges 28 may be increased by changing the shape of the opening 26 in order to make the electrical connection between the contact portion and the bump 40 more reliable. . In order to firmly clamp the bumps 40 with the convex edges 28 during the continuity test, three or more convex edges 28 are preferable.
Further, the probe 22 and the lead 24 need not be the same material. Considering that a load is applied to the probe 22 due to contact with the bump 40 during the continuity test, the probe 22 may be made of a material harder than the lead 24 so that the probe 22 has excellent durability.

Next, a method for manufacturing the probe unit 1 will be described.
FIG. 4 is a cross-sectional view showing a method for manufacturing the probe unit 1.
First, as shown in FIG. 4A, an adhesive 30 is applied to one surface of the substrate 10 except for a portion where a probe is to be formed.
Next, as shown in FIG. 4B, the wiring film 20 is attached to the substrate 10 with an adhesive 30. For the wiring film 20, for example, a nickel alloy such as Ni, Ni—W, or NiFe, or metallic glass is used.

  Next, as shown in FIG. 4C, the wiring film 20 is patterned by lithography and etching to form the outline of the probe 22 and the lead 24, and at the same time, form an opening 26 in the center of the probe 22. The opening 26 can also be formed by stamping. When the opening 26 is formed by stamping, the outer contour of the probe 22 of the wiring film 20 and the patterning of the lead 24 must be performed in separate steps.

Next, as shown in FIG. 4D, the periphery of the opening 26 of the substrate 10 is removed by drilling or the like, and the through holes 12 are formed in the substrate 10.
Next, as shown in FIG. 4E, the convex edge 28 of the wiring film 20 is pushed up from the hole 12 and raised by a hard metal rod 5 having a sharp tip.
Finally, when the unnecessary adhesive 30 exposed on the surface is removed by etching the wiring film 20, the probe unit 1 is completed as shown in FIG.

FIG. 5 is a plan view showing the wiring film 20 patterned in the opening forming step shown in FIG.
As shown in FIG. 5A, when the opening 26 in which the four convex edges 28 are formed is formed, if the convex edge 28 is pushed up and raised, the above-described probe in which the four convex edges 28 are connected in a ring shape. Unit 1 can be formed. As shown in FIG. 5B, when the opening 26 in which the seven convex edges 28 are formed is formed, the above-described probe unit 1 in which the seven convex edges 28 are connected in a ring shape can be formed. As shown in FIG. 5C, the opening 26 itself may be formed in a bellows shape to form five convex edges 28, and the outer edge of the probe 22 may be formed in a substantially elliptical shape. Thus, if the length from the base of the convex edge 28 is formed long, the convex edge 28 can be raised highly. Further, by increasing the size of the through hole, the convex edge 28 of the probe 22 can be lengthened as shown in FIG.

  According to the present manufacturing method, a plurality of probes 22 that make multipoint contact with the bumps 40 are formed on the substrate 10 by a simple manufacturing process without being formed separately from the substrate 10. Specifically, a simple processing technique such as lithography, etching, stamping or the like is used in the process of forming the plurality of openings 26. The process of forming the through hole 12 is also simple. The process of pushing up the plurality of convex edges 28 of each opening 26 of the wiring film 20 from the through hole 12 is also simple. Therefore, a probe unit in which a plurality of probes 22 that are in multipoint contact with the bump 40 are formed at a narrow pitch can be easily manufactured with a simple processing technique without using a complicated manufacturing process.

It is a top view which shows the probe unit by the Example of this invention. It is the sectional view on the AA line of FIG. It is sectional drawing which shows the continuity test method using the probe unit by the Example of this invention. It is sectional drawing which shows the manufacturing method of the probe unit by the Example of this invention. It is a top view which shows the wiring film patterned by the manufacturing method of the probe unit by the Example of this invention. (A) is a top view which shows the probe unit by the Example of this invention, (B) is sectional drawing which shows the probe unit by the Example of this invention.

Explanation of symbols

1 probe unit, 4 specimen, 5 metal rod, 10 substrate, 12 through-hole, 20 wiring film, 22 probe, 24 lead, 26 opening, 28 convex edge, 30 adhesive, 40 bump

Claims (2)

A substrate,
A wiring film having a plurality of openings meandering in outline and formed on the surface of the substrate;
A plurality of convex edges of each opening of the wiring film are raised from the surface of the substrate to form a contact portion that contacts a bump of a specimen. Forming a wiring film having a plurality of openings whose meandering meanders on the surface of the substrate;
Removing the vicinity of each opening of the substrate to form a through hole; and
A process of pushing up a plurality of convex edges of each opening of the wiring film from the through hole, and molding the convex edges into a contact portion that contacts a bump of a specimen;
A method for manufacturing a probe unit comprising:

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