JP5443910B2 - Probe polishing apparatus and probe polishing method - Google Patents

Description

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

  For example, inspection of electrical characteristics of electronic circuits such as ICs and LSIs formed on a semiconductor wafer is performed using a probe card mounted on a probe device. The probe card usually has a plurality of probes and a contactor that supports the probes. The contactor is arranged such that the lower surface on which the probe is supported faces the wafer. The electrical characteristics of the wafer are inspected by bringing a plurality of probes into contact with the electrodes of the electronic circuit formed on the wafer, and through the contactors, the electrical signals for inspection are sent from the probes to the electrodes of the electronic circuit formed on the wafer. Is applied.

  When measuring the electrical characteristics of such an electronic circuit, the aluminum oxide film formed on the electrode surface is scraped to expose the conductive portion of the electrode in order to ensure electrical connection between the electrode of the wafer and the probe. Scrub work is required. Therefore, as shown in FIG. 11, the probe 100 is provided with a beam portion 102 that is supported by the contactor 101 in a cantilever manner and a contact 103 that protrudes from the beam portion 102 toward the wafer W and extends. (Patent Document 1). Then, by applying overdrive so that the contact 103 is in pressure contact with the electrode P of the wafer W, the beam is bent with the fixed end of the beam 102 as a fulcrum, and the contact 103 moves in the direction of the arrow in FIG. Then, the aluminum oxide film on the surface of the electrode P is scraped off by the front end portion 104 of the contact 103, and the front end portion 104 of the contact 103 and the conductive portion of the electrode P come into contact with each other.

JP 2006-1119024 A

  By the way, in the inspection of the electrical characteristics of the electronic circuit using the probe 100 as described above, in order to evaluate the durability and reliability of the device formed on the wafer W, the wafer W is heated to a temperature higher than room temperature, for example, In some cases, the temperature is raised to about 80 ° C. for inspection.

  In the inspection at such a high temperature, the Young's modulus of the probe 100 itself is reduced by heat, so that the amount of bending of the beam portion 102 when the contact 103 is pressed against the electrode P becomes the amount of bending at the time of inspection at room temperature. Compared to larger. Even when the probe 100 is not in pressure contact with the electrode P, the beam portion 102 is warped in the direction opposite to the wafer W due to a temperature difference between the side facing the wafer W in the beam portion 102 and the opposite side thereof. It will occur. For this reason, in the inspection at a high temperature, for example, as shown in FIG. 12, a gap U that opens to the free end side of the contact 103 is formed between the contact surface 105 of the tip 104 and the electrode P. The contact property between the contact surface 105 and the electrode P is not properly maintained.

  When the scrubbing operation is performed in a state where the contact between the contact surface 105 and the electrode P is not maintained, the aluminum oxide film scraped off by the contact 103 is accumulated in the gap U between the contact surface 105 and the electrode P. The oxide film easily adheres to the tip portion 104. When the aluminum oxide film adheres to the tip 104, the attached aluminum oxide film inhibits stable conduction between the probe 100 and the electrode P.

  In such cleaning of the contactor 103, generally, the tip 104 of the contactor 103 is pressed against the cleaning sheet at room temperature to remove the attached matter. However, when cleaning is performed, not only the attached matter but also the contactor 103 is removed. The tip portion 104 itself is also polished and worn.

  Therefore, when the frequency of cleaning the contact 103 increases, there is a problem that the tip 104 of the contact 103 is easily worn and the durability of the probe 100 is deteriorated.

  The present invention has been made in view of such points, and has an object to appropriately maintain the contact property between a probe and an object to be inspected and to reduce the frequency of cleaning in the inspection of the electrical characteristics of the object to be inspected. And

In order to achieve the above object, the present invention provides a method of polishing a probe, which is in contact with an object to be inspected, for inspecting electrical characteristics of the object to be inspected, with an abrasive member, and the probe is separated by a support member. A beam portion to be supported, and a contact provided with a contact surface that extends from the free end of the beam portion toward the object to be inspected and comes into contact with the object to be inspected. The probe is heated to a temperature equal to or higher than the temperature at the time of inspection to warp the beam, and then the contact and the polishing member are relatively moved in a state where the beam is warped by heating , The contact is polished until there is no gap formed between the polishing member and the polishing member. The warp angle is an angle formed by a direction in which the beam portion in a state where no warp occurs and a tangential direction at a free end portion of the beam portion in a state where the beam portion is warped.

According to the present invention, the beam is warped by heating the probe to a temperature equal to or higher than that at the time of inspecting the object to be inspected by the probe , and in that state, the gap formed between the contact surface and the polishing member is eliminated. Since the contact is polished, the contact between the contact and the electrode P is not formed between the contact and the electrode P without forming a gap opening on the free end side of the contact. Can be made. Therefore, the scraped aluminum oxide film can be prevented from accumulating in the gap, and adhesion of the aluminum oxide film to the contact can be suppressed. Thereby, the frequency of cleaning of the contact can be reduced and the durability of the probe can be improved.

The support member may be provided to face the polishing member, and the probe may be heated from the polishing member side.

According to another aspect of the present invention, there is provided a polishing apparatus that polishes a probe that is in contact with an object to be inspected and inspects the electrical characteristics of the object to be inspected, the probe being cantilevered by a support member. And a contact extending from the free end of the beam toward the object to be inspected, a polishing member for polishing the contact of the probe, a heating mechanism for heating the probe, and the probe And a control unit that controls the heating mechanism so as to heat the probe to a temperature equal to or higher than a temperature at the time of inspecting the inspection object .

The support member may be provided to face the heating mechanism, and the polishing member may be provided on the upper surface of the heating mechanism.

  According to the present invention, in the inspection of the electrical characteristics of the object to be inspected, the contact property between the probe and the object to be inspected can be appropriately maintained, and the frequency of cleaning can be reduced.

It is a side view which shows the outline of a structure of a probe apparatus which has the grinding | polishing apparatus concerning this Embodiment. It is a side view which shows the outline of a structure of a probe. It is a side view which shows the state which the contactor and the electrode contacted. It is a side view which shows the state which the beam part curved by heat. It is a side view which shows the outline of a structure of the probe concerning other embodiment. It is a side view which shows the state which the contact and the abrasive paper contacted. It is a side view which shows a mode that the front-end | tip part of a contactor is grind | polished with abrasive paper. It is a side view which shows the state by which the front-end | tip part of the contactor was grind | polished with the abrasive paper. It is a side view which shows the state which the contactor and the electrode contacted. It is a side view which shows the state in which the contactor is moving on an electrode. It is a side view which shows the outline of a structure of the conventional probe. It is a side view which shows the state which the front-end | tip part of the conventional probe and the electrode contact | connected.

  Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 is an explanatory diagram of a side view showing an outline of a configuration of a probe apparatus 1 having a probe polishing apparatus according to the present embodiment.

  The probe device 1 is provided with a probe card 2, a probe polishing device 3 for polishing the probe, and a mounting table 4 on which a wafer W as an object to be inspected is mounted.

  The probe card 2 includes a contactor 11 as a support member that supports a plurality of probes 10 that contact the electrodes of the wafer W on the lower surface, and a printed wiring board 12 that transmits and receives electrical signals to the probe 10 through the main body of the contactor 11. Yes. The probe card 2 can be moved left and right by a moving mechanism (not shown).

  The contactor 11 is provided so as to face the mounting table 4, and the probe 10 supported by the contactor 11 is provided at a position corresponding to the electrode of the wafer W. The contactor 11 and the printed wiring board 12 are formed in a substantially disk shape, for example. The printed wiring board 12 is disposed on the upper surface side of the contactor 11.

  The probe 10 is formed of a magnetic material such as a nickel alloy having conductivity. As shown in FIG. 2, the probe 10 is supported by the contactor 11 and has a support portion 21 that protrudes from the lower surface of the contactor 11. The connection terminal 11a is electrically connected to the printed wiring board 12 by connection pins (not shown), whereby the printed wiring board 12 and the contactor 11 are electrically connected. A beam portion 22 extending in the horizontal direction is provided at the lower end of the support portion 21 formed on the lower surface of the contactor 11, and the beam portion 22 is separated from the contactor 11 at a predetermined interval by the support portion 21. Has been supported. A contact 23 that extends downward in the direction perpendicular to the beam 22 is provided at the free end of the beam 22.

  A flat contact surface 24 a is formed at the tip 24 of the contactor 23 so as to make surface contact with the electrode P of the wafer W. The contact surface 24a is formed, for example, in parallel with the upper surface of the free end portion of the beam portion 22. For example, as shown in FIG. 3, the side surface 25 on the free end side (the X direction positive direction in FIG. 2 (hereinafter referred to as “outside”)) of the beam portion 22 at the distal end portion 24 has a predetermined angle with the electrode P. It is chamfered to have an angle A. A side surface 25 on the fixed end side of the beam portion 22 at the distal end portion 24 (the negative direction in the X direction in FIG. 2 (hereinafter referred to as “inside”)) is also chamfered in the same manner.

  As shown in FIG. 1, the probe polishing apparatus 3 is mounted on a polishing table 30, a heating mechanism 31 as a warp angle adjusting unit of the probe 10 provided on the upper surface of the polishing table 30, and an upper surface of the heating mechanism 31. A polishing paper R is provided as a polishing member. The polishing table 30 is configured to be movable left and right and up and down, and can move the polishing paper R disposed on the upper surface three-dimensionally.

  The configuration and operation of the heating mechanism 31 as the warp angle adjusting unit will be described in detail. The heating mechanism 31 is, for example, a hot plate in which an electric heater is built, and the hot plate can be heated by supplying current to the electric heater by a power supply device (not shown). The heating mechanism 31 is electrically connected to a control unit 32 that adjusts the supplied current and controls the temperature of the heating mechanism 31 to a predetermined temperature.

  In adjusting the warping angle of the probe 10 by the heating mechanism 31, first, an electric current is supplied to the heating mechanism 31 to raise the temperature of the polishing table 30 to a predetermined temperature T. Next, the probe card 2 is moved above the polishing table 30. Thereafter, the polishing table 30 is raised to bring the probe 10 and the polishing table 30 close to each other.

  When the probe 10 and the polishing table 30 are brought close to each other, the surface of the beam portion 22 of the probe 10 facing the polishing table 30 is heated by heat radiation from the heating mechanism 31. On the other hand, since the surface opposite to the beam portion 22, that is, the surface facing the contactor 11 is not easily affected by heat radiation from the heating mechanism 31, a temperature difference occurs between the surface facing the polishing table 30. . Due to this temperature difference, the beam 22 is warped in the contactor 11 direction, that is, upward, with the fixed end of the beam 22 as a fulcrum. Specifically, as shown in FIG. 4, the warping angle B between the horizontal direction, which is the direction in which the beam portion 22 extends before the probe 10 is heated, and the tangential direction of the upper surface of the free end portion of the beam portion 22. Occurs. The angle B is adjusted by controlling the temperature T of the heating mechanism 31 by the control unit 32. Further, since the contact surface 24a is formed in parallel with the upper surface of the free end portion of the beam portion 22, the contact surface 24a also becomes a horizontal plane when the free end portion of the beam portion 22 warps upward at an angle B. On the other hand, the angle B is upward. In the present embodiment, the case where the contact surface 24a and the extending direction of the beam portion 22 are parallel is described. However, the shape of the probe 10 is, for example, as shown in FIG. A case where the film is formed to extend in a direction other than the horizontal direction is also conceivable. Also in this case, the beam portion 22 warps upward with the fixed end portion of the beam portion 22 as a fulcrum, so that the extending direction of the beam portion 22 and the free end portion of the beam portion 22 are the same as in the case of FIG. The warp angle B is generated between the upper surface and the tangential direction of the upper surface, and the contact surface 24a also faces upward with respect to the horizontal plane by an angle B.

  The mounting table 4 is configured to be movable left and right and up and down similarly to the polishing table 30, and moves the mounted wafer W three-dimensionally to contact the probe 10 of the probe card 2 to a desired position on the wafer W. That is, the contact 23 of the probe 3 can be appropriately brought into contact with the electrode P on the wafer W. In addition, a heating mechanism (not shown) is built in the mounting table 4, and the wafer mounted on the upper surface of the mounting table 4 and the mounting table 4 when the wafer W is inspected at a high temperature. W can be heated.

  The probe apparatus 1 according to the present embodiment is configured as described above. Next, a method for polishing the contact 23 of the probe 10 using the probe apparatus 1 and a method for inspecting the electrical characteristics of the electronic circuit of the wafer W using the polished probe 10 will be described.

  In polishing the probe 10, first, the probe card 2 is moved above the heating mechanism 31 that has been heated to a predetermined temperature T. Thereafter, the polishing table 30 is raised, and the probe 10 is warped toward the contactor 11 by the heat of the heating mechanism 31.

  Thereafter, the polishing table 30 is further raised, and the contact 23 is brought into contact with the upper surface of the polishing paper R placed on the polishing table 30. At this time, due to the warp of the beam portion 22 toward the contactor 11, the contact surface 24a of the contact 23 is not surface contact as shown in FIG. 3, but only the inner side N of the contact surface 24a is abrasive paper as shown in FIG. In contact with R, a gap U having an angle B opened to the outside of the contact 23 is formed between the contact surface 24a and the polishing paper R.

  Thereafter, overdrive is applied so that the load of one probe is about 5 to 6 g, for example, so that the contact 23 comes into contact with the polishing paper R at a predetermined contact pressure. As a result, the beam portion 22 bends in the vertical direction as indicated by a broken line in FIG. 5, and a force that moves the contactor 23 outward (in the positive direction of the X direction in FIG. 5) acts. Note that the warp due to the heat of the beam portion 22 and the deflection due to the contact pressure with the polishing paper R are all deformations in the elastic region.

  When the contact pressure reaches a predetermined value, the force that moves the contact 23 outward overcomes the frictional force that acts between the polishing paper R and the tip 24, and the contact 23 and the polishing paper R are relatively horizontal. Movement, that is, the contact 23 moves outward on the polishing paper R. As the contactor 23 moves horizontally on the polishing paper R, the tip 24 of the contactor 23 is polished by the polishing paper R. Then, by repeatedly overdriving and continuing the polishing, as shown in FIG. 7, the contact surface 24a of the tip portion 24 is scraped off by the abrasive paper, thereby eliminating the gap U and forming a new contact surface 24b with it. The

  When polishing is performed until a new contact surface 24b is formed at the tip 24 of the contactor 23, the polishing table 30 is lowered to complete the polishing. As shown in FIG. 8, the new contact surface 24b becomes an inclined surface that gradually increases from the free end side toward the fixed end side, and the inclined surface is an angle C that is an angle greater than or equal to the angle B from the horizontal direction. The shape is only facing up. This is because the beam portion 22 is heated to warp the beam portion at an angle B, and in this state, the contactor 23 is overdriven, and the tip portion 24 and the polishing paper R are brought into contact with each other to perform polishing. Note that the value of the angle C varies depending on polishing conditions such as the temperature T and the contact pressure during heating. In this embodiment, the tip 24 of the contactor 23 is polished by overdrive. However, the polishing may be performed by moving the polishing paper R itself horizontally. In such a case, for example, various methods such as placing the polishing paper R on the polishing table 30 having a rotatable turntable and rotating the polishing paper R by the turntable can be adopted.

  Next, the probe card 2 in which the tip 24 of the probe 10 has been polished is moved above the mounting table 4. The mounting table 4 is heated to a temperature Ta at the time of inspecting the electrical characteristics of the wafer W in advance by a heating mechanism (not shown). The temperature Ta may be any temperature as long as it is equal to or lower than the temperature T at the time of polishing. Here, the temperature Ta will be described as the same temperature as the temperature T at the time of polishing. Thereafter, the mounting table 4 is raised, and the contact 23 of the probe 10 and the electrode P of the wafer W are brought into contact with each other. At this time, the beam portion 22 of the probe 10 is warped by heat from the mounting table 4. The warp angle is the same as the warp angle B of the beam portion 22 at the polishing temperature T shown in FIG. 4 because the temperature Ta during inspection is the same as the temperature T during polishing. Therefore, as shown in FIG. 9, the contact 23 and the electrode P are in contact with each other without forming a gap U that opens on the free end side of the contact 23 between the contact 23 and the electrode P. As shown in FIG. 9, a gap having an angle D that opens to the fixed end side of the beam portion 22 is formed between the contactor 23 and the electrode P. This angle D is due to the difference between the angle C shown in FIG. 7 and the angle B shown in FIG. Further, the angle E between the outer side surface 25 of the contactor 23 and the upper surface of the electrode P is larger than the angle A between the side surface 25 and the electrode P when the probe 10 is at room temperature.

  Next, overdrive is applied so that the load per probe is about 5 to 6 g so that the contactor 23 presses the electrode P with a predetermined contact pressure, and as shown in FIG. The beam portion 22 is bent in the vertical direction, and the contactor 23 is moved outward (in the positive direction of the X direction in FIG. 10). Then, the aluminum oxide film on the surface of the electrode P is scraped off by the tip portion 24 of the contact 23, and the conductive portion of the electrode P is exposed. At this time, the aluminum oxide film of the electrode P is scraped off by the contact 23 without forming a gap U between the contact 23 and the electrode P. The aluminum oxide film is also scraped off by the contactor 23 when the mounting table 4 is lowered and the contactor 23 moves inward (in the negative direction of the X direction in FIG. 10). In the present embodiment, the overdrive load at the time of inspection and the overdrive load at the time of polishing the contactor 23 are both 5 to 6 g. However, the polishing of the contactor 23 is performed as described above. The force that moves the contactor 23 to the outside may be equal to or greater than the frictional force that acts between the abrasive paper R and the leading end 24. Therefore, the load at the time of polishing is not necessarily the same as the load at the time of inspection, and may be, for example, about 2 to 3 g.

  When the aluminum oxide film is scraped off, the electrical characteristics of the electronic circuit of the wafer W are inspected. Thereafter, when the inspection of the electrical characteristics is finished, the wafer W on the mounting table 4 is lowered to a predetermined position, and a series of inspections is finished.

  According to the above embodiment, by heating the beam portion 22 at the same temperature T as the temperature Ta at the time of inspection, the beam portion 22 is warped at the same angle as the warp angle at the temperature Ta at the time of inspection. Since the contact 23 is polished to form a new contact surface 24b, a gap U that opens to the outside of the contact 23 is not formed between the contact surface 24b and the electrode P when the electrical characteristics are inspected. Contact 23 and electrode P can contact. Therefore, the scraped aluminum oxide film can be prevented from accumulating in the gap U, and adhesion of the aluminum oxide film to the contactor 23 can be suppressed. Thereby, the frequency of cleaning of the contact 23 can be reduced, and the durability of the probe 10 can be improved.

  In addition, since the frequency of cleaning is reduced, the number of times inspection is stopped for cleaning is also reduced, so that the time required for inspection can be shortened.

  Further, the contact between the tip 24 of the contact 23 and the electrode P without forming a gap U causes the angle at which the tip 24 and the electrode P are in contact from angle B to angle E. And change. For this reason, the machinability of the aluminum oxide film by the contactor 23 is drastically improved, and the contact pressure for scraping off the aluminum oxide film can be made much smaller than the conventional one. Therefore, the amount of the aluminum oxide film scraped by the contact 23 when the mounting table 4 is lowered can be reduced, and thereby the amount of the aluminum oxide film attached to the contact 23 is further reduced.

  In the above embodiment, the case where the temperature T at the time of polishing the contact 23 is equal to the temperature Ta at the time of inspection has been described. However, when the temperature T at the time of polishing is higher than the temperature Ta at the time of inspection, The warp angle of the beam portion 22 is smaller than the warp angle B of the beam portion 22 at the temperature T during polishing. Therefore, when the electrode P and the contact surface 24b are in contact, the angle D between the electrode P and the contact surface 24b is larger than when the temperature T during polishing and the temperature Ta during inspection are equal. Even in this case, the polished probe 10 and the electrode P are in contact with each other without forming a gap U that is open on the free end side of the contactor 23. Therefore, in the inspection of electrical characteristics by the probe 10, The above effects can be enjoyed without any problem.

  Further, in the above embodiment, the heating mechanism 31 is used as a warp angle adjusting unit that warps the beam portion, and the beam portion 22 is warped upward by heating the beam portion 22 from below, but the probe 10 is made of a magnetic material. For example, a magnetic field generation mechanism 40 that generates a magnetic field is disposed above the probe card 2 as shown by a broken line in FIG. 1, and the beam portion 22 of the probe 10 is warped by the magnetic field generated by the magnetic field generation mechanism 40. May be. In this case, a magnetic material such as nickel, cobalt, or iron can be used as the probe material, and these materials may be partially used at a place where the beam portion 22 is desired to be warped, for example. As the magnetic field generating mechanism 40, for example, an electromagnetic coil can be used. In such a case, by supplying a current to the electromagnetic coil, a magnetic field can be instantaneously formed and the probe 10 can be warped, so that it is possible to reduce the time for preparatory work such as heating of the probe 10 by the heating mechanism 31. . In addition, since the strength of the magnetic field can be precisely controlled by controlling the value of the current supplied to the electromagnetic coil by the control unit 32, the warpage of the probe 10 can be controlled with higher accuracy.

  In the above embodiment, the probe polishing apparatus 3 and the mounting table 4 are provided separately. For example, instead of the wafer W, the polishing paper R is mounted on the upper surface of the mounting table 4 and the probe 10 is mounted. Polishing may be performed. In such a case, first, in a state where the polishing paper R is placed on the placing table 4, the beam portion 22 is heated at a temperature T equal to or higher than the temperature Ta at the time of inspection by the heating mechanism (illustrated) of the placing table 4. Next, the contact 23 is polished in a state where the beam portion 22 is warped at an angle equal to or greater than the warp angle at the temperature Ta at the time of inspection, and then the polishing paper R of the mounting table 4 is replaced with the wafer W. By doing so, the probe 10 can be polished and the electrical characteristics of the electronic circuit of the wafer W can be inspected without using the polishing table 30. That is, the mounting table 4 can be used as the probe polishing apparatus 3. Thereby, it is not necessary to provide the polishing table 30 in the probe apparatus 1, and the probe apparatus 1 can be made compact.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood. The present invention is not limited to this example and can take various forms. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer or a mask reticle for a photomask.

  The present invention is useful for a probe for inspecting electrical characteristics of an object to be inspected, such as a semiconductor wafer.

DESCRIPTION OF SYMBOLS 1 Probe apparatus 2 Probe card 3 Probe polishing apparatus 4 Mounting base 10 Probe 11 Contactor 21 Support part 22 Beam part 23 Contactor 24 Tip part 24a Contact surface 24b Contact surface 25 Side surface 30 Polishing base 31 Heating mechanism 32 Control part P Electrode R Polishing Paper U Gap W Wafer

Claims (4)

A method of polishing a probe that contacts an object to be inspected to inspect the electrical characteristics of the object to be inspected with an abrasive member,
The probe has a beam part that is cantilevered by a support member, and a contact provided with a contact surface that extends from the free end of the beam part toward the object to be inspected and contacts the object to be inspected.
Heating the probe to a temperature equal to or higher than the temperature during inspection of the object to be inspected by the probe, and bending the beam portion;
Next, the contact and the polishing member are relatively moved while the beam portion is warped by heating, and the contact is polished until there is no gap formed between the contact surface and the polishing member. A polishing method characterized by comprising: The support member is provided to face the polishing member,
The polishing method according to claim 1, wherein the probe is heated from the polishing member side. A polishing apparatus that polishes a probe that contacts an object to be inspected and inspects electrical characteristics of the object to be inspected,
The probe includes a beam portion that is cantilevered by a support member, and a contact extending from the free end of the beam portion toward the object to be inspected.
A polishing member for polishing the contact of the probe;
A heating mechanism for heating the probe;
A polishing apparatus comprising: a control unit that controls the heating mechanism so as to heat the probe to a temperature equal to or higher than a temperature at the time of inspection of the inspection object by the probe. The support member is provided to face the heating mechanism,
The polishing apparatus according to claim 3, wherein the polishing member is provided on an upper surface of the heating mechanism.

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