JP2010054264A - Method for manufacturing probe, probe, probe card and probe device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a probe excellent in durability and a method for manufacturing the probe excellent in durability in a desired shape. <P>SOLUTION: The probe includes a probe body provided with a beam portion 24 and has a contact portion 22 including a base 25 which is the contact portion 22 coming into contact with a wafer and is connected to the end portion on the wafer side of the probe body. The method for manufacturing the probe includes a process of relatively pressing a base surface 25a on the wafer side of the base 25 and a plurality of conductive particles 27 so that the conductive particles 27 project from the base surface 25a, and a process of coating the base surface 25a wherefrom the conductive particles 27 project, with a conductive layer 26. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a probe for inspecting electrical characteristics of an object to be inspected and a method for manufacturing the same.

  The electrical characteristics of devices such as ICs and LSIs (hereinafter referred to as “devices”) formed on a semiconductor wafer (hereinafter referred to as “wafers”) are performed using a probe card mounted on the probe apparatus. ing. The probe card usually has a plurality of probes and a contactor that supports the probes. The contactor is disposed such that the lower surface on which the probe is supported faces the wafer. The inspection of the electrical characteristics of the wafer is performed by bringing a plurality of probes into contact with the electrodes on the device and applying an inspection electrical signal from each probe to the electrodes of the electronic circuit on the wafer through the contactor. .

  Since the electrode is made of a conductive metal such as aluminum, for example, the natural oxide film formed on the surface of the electrode cannot be made electrically conductive only by bringing the probe into contact with the electrode. . Therefore, as shown in FIG. 4, a probe 100 having a probe main body 114 having a contact portion 112 bonded to the end portion on the wafer W side and having conductive particles 111 protruding from the contact surface 110 of the contact portion 112 is used. (Patent Document 1). Then, when the conductive particles 111 break through the natural oxide film O formed on the surface of the electrode P, the probe 100 and the electrode P are electrically connected with a low needle pressure.

  Further, as shown in FIG. 5, the method for manufacturing the probe 100 includes a step of forming the mold 121 on the substrate 120 by etching (FIG. 5A), a step of placing the conductive particles 111 on the mold 121 (FIG. 5 (b)), forming a thin film by sputtering, filling the mold 121 with the metal 122 by electroforming (FIG. 5C), and releasing the metal 122 from the mold 121 (FIG. 5D). And a step of etching the lower surface of the metal 122 to project the tip portion 113 of the conductive particle 111 (FIG. 5E).

JP 2005-249693 A

  However, in the method of manufacturing the probe 100 of Patent Document 1, since the lower surface of the metal 122 is immersed in the etching solution in order to make the conductive particles 111 protrude, the etching solution enters between the conductive particles 111 and the metal 122 and the metal A gap is formed between the conductive particles 111 and the conductive particles 111, and the conductive particles 111 are easily removed from the contact portions 112. As a result, when the probe 100 comes into contact with the electrode P during device inspection, the conductive particles 111 are removed from the contact portion 112. Therefore, the probe 100 has no durability and cannot be tested with high reliability.

  Conventionally, since electroforming is performed after the conductive particles 111 are placed on the bottom surface of the mold 121, the contact portion 112 is formed so that the contact surface 110 is positioned on the bottom surface side of the mold 121 (see FIG. 5). Then, for example, when a probe consisting of a probe body and a contact portion is manufactured collectively by electroforming, it is necessary to stack the mold so that the contact portion is in the bottom layer and the beam portion is in the second layer above it. However, in order to form these molds on the substrate, photolithography must be repeated many times. Further, since processing by photolithography is performed downward from the surface of the substrate, it is difficult to stack a plurality of molds on the substrate, and it is difficult to process the substrate. As described above, since a substrate is conventionally required for manufacturing a probe, the shape of the probe that can be manufactured is limited.

  The present invention has been made to solve the above-mentioned problems, and provides a probe manufacturing method that provides a probe having excellent durability and manufacturing the probe having excellent durability in a desired shape. It is aimed.

  In order to solve the above-described problems, the present invention provides a probe main body, a contact portion that contacts an object to be inspected, and a contact portion that includes a conductive base connected to an end of the probe main body on the object to be inspected; A probe having a plurality of conductive particles are relatively pressed against the surface of the substrate on the side to be inspected, and the plurality of conductive particles protrude from the surface of the substrate. A pressing step provided on the surface, and a covering step of covering at least the surface of the substrate other than the plurality of conductive particles on the surface to be inspected with a conductive layer. The covering step may be performed by plating, sputtering, or CVD. Further, the substrate may be heated before the pressing step.

  According to the present invention, since the contact portion is formed by the pressing step and the covering step without using an etching solution, the durability of the probe is improved and a highly reliable inspection can be performed. In addition, since the contact portion is formed by the pressing step and the covering step without using the substrate, the conductive particles can be joined regardless of the shape of the probe.

  In the probe manufacturing method of the present invention, the conductive layer may be formed of a platinum group element or an alloy containing at least one of the platinum group elements. In particular, the platinum group elements include rhodium (Rh) and ruthenium. (Ru), iridium (Ir) or rhenium (Re) may be used. Conventionally, since the metal 122 is formed by electroforming as shown in FIG. 5, it has been limited to materials having low hardness such as nickel (Ni) and copper (Cu). In this case, when the probe 100 shown in FIG. 4 is in contact with the electrode P during device inspection, these metals have low hardness, so that the contact surface 110 is easily worn and the conductive particles 111 are easily removed. . Therefore, the probe 100 has no durability and a highly reliable test cannot be performed. According to the present invention, since the conductive layer is formed of a platinum group element or an alloy containing at least one of the platinum group elements, the conductive particles are firmly fixed to the substrate, and are the surface of the conductive layer. Since the contact surface is less likely to wear, it is difficult to remove the conductive particles from the contact portion. Therefore, the durability of the probe is improved and a highly reliable test can be performed.

  In order to solve the above problems, the present invention provides a probe for inspecting the electrical characteristics of an object to be inspected by bringing the contact part into contact with the object to be inspected, wherein the contact part has a conductive base. A plurality of conductive particles provided on the surface of the base so as to protrude from the surface of the base to be inspected, and at least the surface of the base other than the plurality of conductive particles in the base. And a conductive layer. The conductive layer may be formed of a platinum group element or an alloy containing at least one of the platinum group elements, and in particular, the platinum group element includes rhodium (Rh), ruthenium (Ru), iridium (Ir) or Rhenium (Re) may be used. As a result, the conductive particles are firmly fixed to the substrate, and the contact surface, which is the surface of the conductive layer, is less likely to be worn away, making it difficult to remove the conductive particles from the contact portion. Therefore, the durability of the probe is improved and a highly reliable test can be performed.

  Another aspect of the present invention includes a probe card and a probe device characterized by using the probe of the present invention, and a highly reliable test can be performed using these probe card and probe device.

  ADVANTAGE OF THE INVENTION According to this invention, the probe excellent in durability can be provided and the manufacturing method which manufactures the probe excellent in durability with a desired shape can be provided.

  Hereinafter, the present invention will be described based on the embodiment shown in FIGS. In addition, the same code | symbol is attached | subjected to the same or equivalent part in a figure, and the description is not repeated.

  FIG. 1 is a side view showing an outline of the configuration of a probe apparatus 1 including the probe of the present embodiment. The probe device 1 is provided with a probe card 2 and a mounting table 3 on which a wafer W as an object to be inspected is mounted. The mounting table 3 is configured to be movable left and right and up and down, and the mounted wafer W can be moved three-dimensionally.

  The entire probe card 2 is formed in a disk shape, for example. The probe card 2 is a circuit board 10 that sends an electrical signal for inspection to a device formed on the wafer W, and an inspection that contacts the electrode P of the device and electrically connects the circuit board 10 and the wafer W. A contact structure 11 is provided.

  The circuit board 10 is formed in a disk shape, for example, and is electrically connected to a tester (not shown). On the circuit board 10, an electronic circuit (not shown) for transmitting an electrical signal for inspection with the inspection contact structure 11 is mounted. An electrical signal for inspection from the tester is transmitted to and received from the inspection contact structure 11 via the electronic circuit of the circuit board 10. A connection terminal (not shown) is arranged on the lower surface of the circuit board 10, and this connection terminal is formed as a part of the electronic circuit of the circuit board 10.

  The inspection contact structure 11 has a support plate 12. The support plate 12 is formed in a square shape, for example, and is disposed on the lower surface side of the circuit board 10 so as to face the mounting table 3 and to be parallel to the circuit board 10. For the support plate 12, for example, an insulator such as ceramics or glass is used. A connection terminal (not shown) is provided on the upper surface of the support plate 12 and is electrically connected to the connection terminal of the circuit board 10. A probe 20 arranged so as to correspond to the electrode P of the wafer W is provided on the lower surface side of the support plate 12.

  FIG. 2 shows an outline of the probe 20 of the present embodiment. The probe 20 has a cantilever type shape, and includes a probe main body 21 and a contact portion 22 connected to the end of the probe main body 21 on the wafer W side. The device electrode P on the wafer W is formed of, for example, a conductive metal such as aluminum or copper, and a natural oxide film O is formed on the surface of the electrode P on the probe 20 side.

  The probe body 21 protrudes from the lower surface of the support plate 12 and is held by the support plate 12. The probe body 21 has a support portion 23, and the upper end of the support portion 23 is connected to a connection terminal (not shown) provided on the lower surface of the support plate 12. Electrical connection with the tester is ensured by electrical connection. A beam portion 24 is provided at the lower end of the support portion 23, and the beam portion 24 is cantilevered by the support portion 23. The free end portion of the beam portion 24 is provided with a contact portion 22 that extends downward in the direction perpendicular to the beam portion 24 and contacts the electrode P of the device. The probe body 21 is formed by, for example, electroforming, and for example, nickel is used as a material.

  The contact portion 22 is formed, for example, in a substantially cylindrical shape, and includes a base body 25 that extends from the free end portion of the beam portion 24 to the lower side in the direction perpendicular to the beam portion 24. The surface of the base 25 on the wafer W side is covered with a conductive layer 26, and the conductive layer 26 fixes conductive particles 27 embedded in the base 25. The contact surface 28 is a surface in contact with the device electrode P or the natural oxide film O, and is composed of the surface of the conductive layer 26 on the wafer W side and the surface of the conductive particles 27 protruding from the surface.

  In the present embodiment, nickel (Ni) having excellent conductivity is used for the base 25, but it is not limited to nickel as long as it is a material having conductivity.

  The material of the conductive layer 26 may be any material having conductivity such as nickel (Ni) or copper (Cu). Further, from the viewpoint of hardness, oxidation resistance, wear resistance, adhesion to other metals, etc., the conductive layer 26 includes a platinum group element or an alloy containing at least one of the platinum group elements, such as a platinum group element. Rhodium (Rh), ruthenium (Ru), iridium (Ir), or rhenium (Re) is more preferably used. The conductive particles 27 are formed so as to be difficult to remove.

  The conductive particles 27 are formed of a material that is conductive and has a hardness higher than that of the base 25, such as conductive diamond, SiC, TiC, tungsten (W), and molybdenum (Mo). The conductive particles 27 protrude from the surface of the conductive layer 26 by a predetermined dimension, break through the natural oxide film O of the electrode P and make electrical contact with the electrode P during inspection, and establish electrical continuity between the probe 20 and the electrode P. It is formed as follows. Further, the shape of the conductive particles 27 is, for example, a polygonal shape in order to efficiently break through the natural oxide film O on the electrode P.

  In the present embodiment, for example, the conductive particles 27 have a diameter of 2 μm, the contact surface 28 has a diameter of 20 μm, and the conductive layer 26 has a thickness of 1.5 μm. In addition, the conductive particles 27 protrude from the conductive layer 26 by 0.3 μm. On the other hand, the electrode P has, for example, an aluminum conductive layer formed to a thickness of 1 μm, and a natural oxide film O of about 0.1 μm is formed on the surface thereof.

  Next, the operation of the probe 20 according to the present embodiment when inspecting the electrical characteristics of the wafer W will be described in detail.

  First, as shown in FIG. 1, after placing the wafer W on the mounting table 3, when the mounting table 3 moves in the horizontal direction, the wafer W reaches just below the inspection contact structure 11. By raising the mounting table 3, the conductive particles 27 and the electrode P come into contact with each other. Next, by applying overdrive while increasing the contact pressure between the probe 20 and the electrode P, a needle pressure of about 1 g / piece is applied to the probe 20. Due to the overdrive of the mounting table 3, the conductive particles 27 penetrate the natural oxide film O of the electrode P and bite into the electrode P.

  Then, the contact portion 22 moves horizontally due to overdrive, and the natural oxide film O is scraped off. By this scrubbing, the probe 20 and the electrode P are electrically connected, and the electrical characteristics of the device can be inspected.

  According to the above embodiment, the conductive particles 27 are firmly fixed to the base 25 by the covering with the conductive layer 26, and the contact surface 28 is not easily worn. It becomes difficult to remove. Therefore, the durability of the probe 20 is improved and a highly reliable test can be performed. For the conductive layer 26, a platinum group element or an alloy containing at least one of the platinum group elements, particularly rhodium (Rh), ruthenium (Ru), iridium (Ir), or rhenium (Re) can be preferably used. . Thereby, the electroconductive particle 27 is firmly fixed by the base | substrate 25, and the contact surface 28 becomes more difficult to wear.

  Further, by making the conductive particles 27 a material having high hardness, for example, conductive diamond, SiC, TiC, tungsten (W), molybdenum (Mo), the electrical characteristics of the device can be inspected with a low needle pressure. . At this time, since the conductive particles 27 protrude from the conductive layer 26 by a predetermined dimension, when the conductive particles 27 reach a predetermined depth in the electrode P, the conductive layer 26 faces the electrode P or the natural oxide film O. Since it contacts and functions as a stopper, the electrical characteristics of the device can be inspected without causing the conductive particles 27 to bite into the electrode P any more and damaging the electrode P excessively.

  Hereinafter, a method for manufacturing the probe 20 of the present embodiment will be described. First, the beam portion 24 and the base body 25 are integrally formed (FIG. 3A). At this time, the conductive particles 27 are separated from the base body 25. Then, the plurality of conductive particles 27 are pressed against the substrate surface 25a of the substrate 25 using the pressing member 29 (FIG. 3B). When the force F is applied to the pressing member 29, the conductive particles 27 are pressed against the base body 25. At this time, a plurality of dents are formed in the base surface 25a according to the shape of the conductive particles 27, and the conductive particles 27 adhere to the base surface 25a so that the conductive particles 27 protrude from the base surface 25a. Provided. The pressing member 29 has a pressing surface 29a on the side facing the base 25, and the pressing surface 29a is formed in a flat shape, for example. In addition, since the conductive particles 27 are pressed against the pressing member 29 and the base body 25, the pressing member 29 is made of glass or aluminum nitride, for example, more than the base body 25 so that the conductive particles 27 adhere to the base body 25. It is made of a hard material. In this embodiment, the force F is applied to the pressing member 29 and the conductive particles 27 are pressed against the base 25. However, the base 25 may be pressed against the conductive particles 27 by applying a force to the base 25 side.

  Next, the conductive layer 26 is covered to fix the conductive particles 27 to the base body 25 (FIG. 3C). The conductive layer 26 may be coated by any method as long as the conductive layer 26 can be coated on the substrate surface 25a and the conductive particles 27 can be fixed, and preferably plating, sputtering, or CVD is used. The material of the conductive layer 26 may be any material having conductivity such as nickel (Ni) or copper (Cu). From the viewpoint of hardness, oxidation resistance, wear resistance, adhesion to other metals, etc., a platinum group element or an alloy containing at least one of the platinum group elements, for example, rhodium (Rh) as a platinum group element. Ruthenium (Ru), iridium (Ir) or rhenium (Re) is more preferably used.

  According to the above embodiment, the contact portion 22 is formed by pressing the conductive particles 27 against the base 25 and coating the conductive layer 26 on the base surface 25a without using an etching solution as in the prior art. As a result, the durability of the probe 20 is improved, and a highly reliable test can be performed. Further, the contact portion 22 is formed by pressing the conductive particles 27 against the base 25 and covering the base surface 25a with the conductive layer 26 without using a substrate as in the prior art. Regardless, the conductive particles 27 can be joined. In particular, when the probe main body 21 and the base body 25 are integrally formed of the same material, or when the contact portion 22 has a complicated shape, the conductive particles 27 can be connected to the contact portion 22 in the final process. The manufacturing process of the probe 20 is not limited to electroforming plating as in the prior art, and may be machining or the like.

  In the present embodiment, the conductive layer 26 is formed of a platinum group element or an alloy containing at least one of the platinum group elements. In particular, rhodium (Rh), ruthenium (Ru), iridium (Ir ) Or rhenium (Re). As a result, the conductive particles 27 are firmly fixed to the base 25 and the contact surface 28 is less likely to be worn away, making it difficult to remove the conductive particles 27 from the contact portion 22. Therefore, the durability of the probe 20 is improved and a highly reliable test can be performed.

  In addition, this invention is not restrict | limited to the said embodiment at all. In the above embodiment, the probe has been described as a cantilever type probe, but it may be a vertical type probe such as a pogo pin. In the case of a vertical probe, since scrub does not occur due to overdrive, the load must be increased in order to establish conduction with the electrode. By using the probe of the present invention, an oxide film can be formed at a low needle pressure. Can be broken.

  Further, at least a part of the probe main body 21 and the base body 25 may be integrally formed of the same material. For example, when the probe main body 21 and the base body 25 are integrally formed using a substrate, or integrally formed with a wire. May be.

  The conductive layer 26 only needs to be formed so as to cover at least the substrate surface 25 a, and may cover the conductive particles 27.

  When manufacturing the probe 20, the substrate 25 may be heated before the step of pressing the conductive particles 27 against the substrate 25. When the substrate 25 is softened by heating, the conductive particles 27 can be pressed with a force smaller than that at room temperature. The substrate 25 may be heated until it becomes soft enough to embed the conductive particles 27 in the metal material constituting the substrate 25. The heating temperature of the substrate 25 is, for example, from room temperature to the metal softening temperature of the substrate 25. It can set suitably within the range.

  The present invention can be suitably used, for example, as a probe for an inspection apparatus and a method for manufacturing the probe.

It is a side view which shows the probe apparatus to which the probe of this Embodiment is applied. It is a longitudinal cross-sectional view which shows the state which the probe and electrode of this Embodiment adjoined. (A)-(d) is a longitudinal cross-sectional view which shows the principal part of the manufacturing process of the probe shown in FIG. It is a longitudinal cross-sectional view which shows the outline | summary of the probe of a prior art. It is a longitudinal cross-sectional view which shows the outline | summary of the manufacturing method of the probe of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Probe apparatus 2 Probe card 3 Mounting stand 10 Probe card 11 Contact structure for a test | inspection 12 Support body 20 Probe 21 Probe main body 22 Contact part 23 Support part 24 Beam part 25 Base 25a Base surface 26 Conductive layer 27 Conductive particle 28 Contact surface 29 Pressing member 29a Pressing surface W Wafer P Electrode O Natural oxide film F Force

Claims (10)

A method of manufacturing a probe having a probe main body and a contact portion that is in contact with an object to be inspected and includes a conductive base connected to an end of the probe main body on the object to be inspected,
A pressing step of relatively pressing the surface of the substrate to be inspected and the plurality of conductive particles, and providing the plurality of conductive particles on the substrate surface so as to protrude from the substrate surface;
And a coating step of covering at least the surface of the substrate other than the plurality of conductive particles on the substrate side with a conductive layer. The method of manufacturing a probe according to claim 1, wherein the covering step is performed by plating, sputtering, or CVD. The probe manufacturing method according to claim 1, wherein the substrate is heated before the pressing step. The method for manufacturing a probe according to claim 1, wherein the conductive layer is formed of a platinum group element or an alloy containing at least one of the platinum group elements. 5. The method of manufacturing a probe according to claim 4, wherein the platinum group element is rhodium (Rh), ruthenium (Ru), iridium (Ir), or rhenium (Re). A probe for inspecting the electrical characteristics of an object to be inspected by bringing the contact portion into contact with the object to be inspected,
The contact portion includes a base having conductivity, a plurality of conductive particles provided on the surface of the base so as to protrude from the surface of the base on the object to be inspected, and the plurality of conductive particles on the at least the base. And a conductive layer that covers the surface on the inspected object side other than the probe. The probe according to claim 6, wherein the conductive layer is made of a platinum group element or an alloy containing at least one of the platinum group elements. The probe according to claim 7, wherein the platinum group element is rhodium (Rh), ruthenium (Ru), iridium (Ir), or rhenium (Re). A probe card using the probe according to claim 6. A probe device using the probe according to claim 6.

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