JP2012194133A - Probe cleaning apparatus and probe cleaning method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning apparatus for removing a foreign substance stuck to a tip of a probe to be used for a test step of a semiconductor device or an integrated circuit and preventing occurrence of stick slip on the tip of the probe.SOLUTION: The cleaning apparatus includes: a vertical direction drive mechanism 23 for attaching a probe 11 having a spherical tip part or an inclined part straight extended from the halfway of the spherical tip part; horizontal direction drive mechanisms 32, 42 for stages 30, 40 for fixing a cleaning sheet 50; and a control device 60. The horizontal drive mechanisms 32, 42 are driven and controlled so that the pressing quantity of the probe 11 to the cleaning sheet 50 is continuously increased to a predetermined value by the control device 60 and a moving locus of the probe tip part 12 to the cleaning sheet 50 becomes a closed loop by the vertical direction drive mechanism 23.

Description

  The present invention relates to a probe used in a test process of a semiconductor device or an integrated circuit, and more particularly to a cleaning device that removes foreign matter adhering to the probe tip and a probe cleaning method using the device.

The probe is used as an electrical contact for applying a current or a voltage when inspecting a semiconductor device or the like, and is a conductive terminal for connecting an electrode and an inspection circuit called a tester. Repeated contact of the probe and current application causes the electrode material on the surface of the semiconductor device to adhere to the probe tip. This adhesion increases the electrical resistance (contact resistance) formed at the probe tip and the surface of the semiconductor device. This increase in contact resistance causes a contact failure with the semiconductor device, and thus hinders proper inspection of the semiconductor device.
2. Description of the Related Art Conventionally, in a semiconductor device test process, the life of a probe is extended by periodically removing deposits deposited on the probe tip with a cleaning sheet or the like.

  For example, as a conventional technique, a base plate, a first elastic member formed on the base plate, a second elastic member formed on the first elastic member, and a hard material formed on the second elastic member More specifically, the Young's modulus of the first elastic member is 5 kgf / mm 2 or more and 400 kgf / mm 2 or less, and the film thickness of the second elastic member is 0. 1 μm or more and 20 μm or less, the tensile strength of the second elastic member is 0.1 kgf / mm 2 or more, the volume ratio of the hard particles to the polishing layer is 5% or more and 70% or less, and the particle size of the hard particles is 0.1 μm The probe tip adhering foreign matter removing member having a size of 9 μm or less is placed on the wafer stage, and the probe having a tip having a substantially spherical shape or a shape having a flat portion on a part of the substantially spherical surface is a member for removing the probe tip attached foreign matter. above And to then slip operation draws a locus of a loop shape, a method of cleaning a probe tip attached foreign substance, characterized in that to remove the tip adhesion foreign matter of the probe is shown (e.g., Patent Document 1).

Further, in a prober having a cleaning mechanism for removing foreign matter adhering to the probe needle, the cleaning mechanism has at least a cleaning plate, an ultrasonic oscillator, and an oscillator controller, and when the probe is pressed against the cleaning plate for cleaning, A prober characterized in that a cleaning plate is ultrasonically oscillated by an ultrasonic oscillator to efficiently remove foreign substances adhering to the probe is disclosed (for example, Patent Document 2).
Still further, a probe needle polishing apparatus that polishes and cleans the tip of a probe needle that is brought into contact with an inspection target for electrical property inspection, the polishing plate placed on the substrate and brought into contact with the probe needle for cleaning, and the substrate An air cylinder that moves the polishing plate up and down through, and a rotating device that rotates the polishing plate through the substrate. The rotating device rotates the polishing plate in the direction opposite to the forward direction by at least the probe needle diameter, A probe needle polishing apparatus having a function of varying the rotation speed is disclosed. It has been shown that stress on the probe needle can be alleviated not only by continuously pressing the probe needle with a constant force but also by changing the amount of pressing intermittently (for example, Patent Document 3).

Japanese Patent No. 3888390 JP 2004-039790 A JP 2007-155369 A

However, since the technique disclosed in Patent Document 1 is a method of moving the probe tip in the horizontal direction of the cleaning sheet in a closed loop shape, depending on the probe holding structure, the sheet horizontal direction determined by the distance from the probe tip to the holding portion is used. Depending on the relationship between the probe spring constant and the load applied to the probe tip in the horizontal direction, the probe tip may stick-slip on the sheet, and the attached matter may not be removed.
In addition, the technique disclosed in Patent Document 2 applies a horizontal operation to the cleaning sheet using ultrasonic vibrations to remove deposits. However, the frequency of ultrasonic vibrations is high, and the probe tip is abrupt. Since the amount of displacement in the horizontal direction is given, the strength of the probe may be reduced. Accordingly, the horizontal reaction force acting on the probe tip when contacting the sheet increases, and there is a problem of stick-slip.
Furthermore, the technique disclosed in Patent Document 3 has been shown to relieve stress on the probe needle by changing the push-in amount. This operation reverses the amount of pushing in the positive and negative directions with respect to the probe pushing direction. When the probe tip has an R shape, the tip of the probe tip must be polished to maintain the tip shape, and the probe tip sinks to some extent. It is necessary to increase the push-in amount until it is inserted. Therefore, the above operation has a problem that the tip of the R-shaped probe is flattened.

  The present invention has been made to solve the above-mentioned problems, and has improved the removal efficiency of the probe tip deposits, eliminated stick slip on the cleaning sheet, and improved the probe tip shape. An object of the present invention is to provide a probe cleaning device and a probe cleaning method.

  The probe cleaning device used for the electrical characteristic inspection according to the first aspect of the invention is a probe provided with a spherical tip formed with a curvature R, or an inclination extending linearly from the middle of the spherical tip. A vertical driving mechanism for mounting a probe provided with a section, a stage for fixing a cleaning sheet for removing foreign matter adhering to the tip of the probe, a horizontal driving mechanism for the stage, and a vertical and horizontal driving mechanism A control device that controls the drive of the vertical direction drive mechanism until the probe tip is pushed into the cleaning sheet a plurality of times until the push amount continuously increases to a predetermined value. In addition, the horizontal drive mechanism is driven so that the movement trajectory of the cleaning sheet relative to the probe tip is a continuous closed loop. It is Gosuru thing.

  According to a second aspect of the present invention, there is provided a probe cleaning method for cleaning a probe using the cleaning apparatus according to the first aspect.

Since the probe cleaning device according to the first invention employs the above-described configuration, there is an effect of preventing stick slip caused by the probe tip on the cleaning sheet. It is also possible to clean multiple probes, reducing the effects of mounting accuracy that changes with each cleaning, making off-line cleaning easier, easier operation on the production line, and more reliable cleaning. There is an effect that can be done. Further, there is an effect of finishing the probe tip more uniformly derived from this effect.
The probe cleaning method according to the second aspect of the present invention uses the above-described probe cleaning device, and therefore has the same effect.

It is a perspective view which shows the whole cleaning apparatus. It is sectional drawing which showed the relationship between a probe and a cleaning sheet. It is the graph which showed the locus | trajectory of the probe front-end | tip part of the X, Y direction, and Z direction in the pushing increase. It is the graph which showed the locus | trajectory of the probe front-end | tip part of the X, Y direction, and Z direction in step-like pushing increase. It is the figure which showed the locus | trajectory of the probe front-end | tip part of the X and Y direction in cleaning. It is sectional drawing of the probe jig | tool and attachment explaining the time of attachment attachment.

Embodiment 1 FIG.
Prior to the detailed description of the first embodiment, problems related to the conventional probe cleaning apparatus and cleaning method will be described once again.
The method of moving the probe tip in the horizontal direction in a closed loop is based on the probe spring constant in the sheet horizontal direction determined by the distance from the probe tip to the holding part that holds the probe, and the load that the probe tip receives in the horizontal direction. Therefore, there is a problem in that the probe tip sticks and slips on the cleaning sheet and cannot be properly cleaned.
For example, when a probe having a probe holding portion to a probe tip of 1.0 mm, a probe diameter of 0.11 mm, and a material of tungsten is cleaned by horizontal movement using a cleaning sheet having a cushion layer under the polishing layer. The push-in range where stick-slip does not occur is as small as about 0.03 mm. Therefore, in order to clean a plurality of probes attached to the probe holding portion so that the probe tips are substantially flush with each other at the same time, the length accuracy of the probe alone and the mounting accuracy to the cleaning device are required. The With the in-line cleaning method that repeats inspection and cleaning with the probe jig attached to the inspection head fixed to the inspection head, the accuracy of attachment to the device does not change, and the length of the probe becomes uniform when cleaning is repeated. Although easy, the off-line cleaning method in which the attachment / detachment of the probe jig occurs has a problem that the accuracy of the attachment to the cleaning device changes every cleaning, so that the finish of the probe tip and the cleaning amount vary from probe to probe.
Further, since the cleaning sheet for maintaining the R shape having the probe tip in a spherical shape has a structure in which the polishing layer sinks by pushing the probe, the probe tip side portion is polished during horizontal movement cleaning.
The cleaning of the probe tip side portion sharply cuts the probe tip portion, so that the strength of the probe tip portion is reduced and problems such as probe breakage may occur.
On the other hand, if too much effort is made to remove the deposit at the center of the probe tip, the R shape of the probe tip changes to a flat shape. Must be able to polish the probe tip side portion less.

The present invention has been made to solve the above-described problems in addition to the problems described in Patent Documents 1 to 3 described above.
Hereinafter, description will be given based on FIGS.
FIG. 1 is a perspective view showing the entire probe cleaning apparatus 100 according to the first embodiment. In FIG. 1, an X stage 30 is installed on a pedestal 1 and linearly moves in the X axis direction on an X stage guide 31 by an X direction driving device 32 such as a ROBO Cylinder. The Y stage 40 is installed on the X stage 30 and moves straight on the Y stage guide 41 in the Y direction by a Y direction driving device 42 such as a ROBO cylinder. The cleaning sheet 50 is installed on the Y stage 40. The cleaning sheet 50 is driven in the horizontal direction by a horizontal driving mechanism including these X and Y direction driving devices 32 and 42.
That is, the Y stage 40 is linearly moved on the X stage 30 in the X direction, and the cleaning sheet 50 on the Y stage 40 is linearly moved in the Y direction. As a result, the cleaning sheet 50 is moved on the stage in the X direction. , Move in both horizontal directions in the Y direction.
As a vertical mechanism for moving the probe 11 in the Z direction, which is the vertical direction, a probe head 21 is installed on the pedestal 1 and moves linearly in the vertical direction on the probe head guide 22 by a Z direction driving device 23 such as a ROBO Cylinder. The probe cassette holder 20 is attached to the probe head 21, and the probe jig 10 is attached to the probe cassette holder 20. The probe 11 is held by the holding portion 10 a of the probe jig 10.
With such a configuration of the probe cleaning apparatus 100, the probe 11 and the cleaning sheet 50 move relative to each other in the X, Y, and Z directions.

  For example, the probe 11 that repeatedly inspected the semiconductor device is removed from the inspection apparatus after inspecting a predetermined lot. This probe 11 is attached to a probe cleaning device 100 having a probe jig 10 similar to that of the inspection device, and cleaning is performed.

FIG. 2A is a cross-sectional view showing the relationship between the probe 11 and the cleaning sheet 50.
As shown in the enlarged view of the probe 11 in FIG. 2B, the probe tip 12 of the probe 11 has a spherical shape 12c having a curvature R or as shown in the enlarged view of the probe 11 in FIG. An inclined portion 12d that extends straight from the middle of the spherical surface 12c is provided. The cleaning sheet 50 has a polishing layer 51 on the surface layer. The polishing layer 51 is made of, for example, SiC-based abrasive grains hardened with a resin binder. The cushion layer 52 of polyurethane foam, which is an elastic-plastic material, is formed in the lower layer. Further, the lower layer has a base plate 53 such as a PET film, and the lower portion of the base plate 53 has an adhesive layer 54 for fixing the cleaning sheet 50 to the Y stage 40. Here, symbols X ₁ and X ₅ shown in FIG. 2 indicate positions where the cleaning sheet 50 moves, and coincide with X ₁ and X _{5 on} the X axis in FIGS. 3 and 4 described later.
The probe 11 includes a spring probe that makes contact using the reaction force of a spring, a wire probe that makes contact using the reaction force of a wire deflection, and a cantilever that makes contact by converting bending of the probe into a side-slip force. However, cleaning is possible regardless of the method of the probe 11.
The probe tip 12 tends to deposit, for example, aluminum deposits 13 at the probe tip center 12a. When the probe tip 12 is spherical, the contact area between the probe tip 12 and the semiconductor device of the object to be inspected is the probe tip center 12a. Deposit on 12a.

Hereinafter, the cleaning operation of the probe tip portion 12 will be described based on the graph showing the trajectory of the probe tip portion 12 in the X direction and the Z direction when the push amount is increased by a small amount in FIG.
In FIG. 3 and FIG. 4 described later, the positional relationship between the probe trajectories in the X direction and the Y direction is a closed loop as shown in FIG. In the probe cleaning apparatus 100 shown in FIG. 1, the cleaning operation includes an operation of continuously moving the probe tip 12 to a predetermined position in the Z direction, and the cleaning sheet 50 on the Y stage 40. This is realized by a combination of operations for continuously moving to predetermined positions in the X and Y directions.
That is, the probe tip 12 is lowered to the vicinity of the polishing layer 51 of the cleaning sheet 50, and the cleaning sheet 50 is (X ₁ , Y ₁ ) → (X ₂ , Y ₂ ) → (X ₃ , Y ₃ ) in FIG. → (X ₄ , Y ₄ ) → (X ₅ , Y ₅ ) → (X ₁ , Y ₁ ) and move continuously several millimeters to draw a closed loop. The closed loop shape can be appropriately selected according to the probe arrangement such as linear movement or arc motion. Thus, from the state of X ₁ and Y ₁ , the probe tip 12 is gradually moved in the thickness (depth) direction of the cleaning sheet 50 by the Z-direction drive device 23, and the cleaning sheet 50 operates in the X and Y directions. And the Z-direction movement of the probe tip 12 are combined, and the aluminum deposit 13 on the probe tip 12 is removed by polishing with the polishing layer 51.
The combination of the X and Y direction operations and the Z direction operations is controlled by the control device 60 shown in FIG. 1 having programmed software.

For example, when cleaning the probe tip 12 having the spherical shape 12c, the diameter of the probe 11 is 0.1 mm, the probe protruding amount from the holding portion 10a shown in FIG. 1 is 0.5 mm, and the probe for forming the spherical shape 12c. The curvature R of the tip 12 is 0.05 mm. The abrasive grains used for the polishing layer 51 of the cleaning sheet 50 are effective when the grains are about # 4000 to # 10000.
In order to remove the aluminum deposit 13 attached to the probe tip 12, it can be removed by setting the horizontal movement amount in the X and Y directions to several millimeters.
When the curvature R of the probe tip 12 is about 0.05 mm, the final push amount of the probe 11 is about 0.03 mm to 0.05 mm which is a predetermined value from the state where the probe tip center 12 a touches the polishing layer 51. It is preferable to set so that. Further, the Z position to be touched down can be determined by preparing a cleaning sheet sample to which the Z movement amount is distributed and checking the traces left on the cleaning sheet sample with a microscope.
In addition, in order not to cause stick slip, it is not a necessary condition to start horizontal movement in the X and Y directions from the Z position where touchdown is performed. For example, even when the horizontal movement in the X and Y directions is started from a state in which the probe center 12a and the polishing layer 51 are separated from each other by about 0.01 mm, the push amount is gradually increased. It goes without saying that the same effect can be obtained if the final pushing amount reaches 0.03 mm to 0.05 mm.
At this time, if the probe tip center 12a is pushed into the polishing layer 51 to 0.05 mm at a time and moved horizontally, the probe protruding from the probe jig 10 having a diameter of 0.1 mm and a length of 0.5 mm moves horizontally. It is easy to stick-slip against the horizontal reaction force that sometimes occurs. The locus left on the polishing layer 51 after stick-slip is very uneven, and the cleaning finish of the probe tip 12 is also deteriorated.

In the first embodiment, the pushing amount is gradually and continuously increased slightly. Therefore, in the cleaning operation, the aluminum deposit 13 adhering to the probe tip center 12a comes into contact with the polishing layer 51 of the cleaning sheet 50 earliest and starts cleaning. Thereafter, the pushing in the Z direction is increased, and the probe tip 12 gradually sinks together with the polishing layer 51 by the effect of the cushion layer 52 which is an elastic-plastic material.
In such a cleaning operation, the probe tip center 12a is polished for a longer time than the probe tip side 12b, so that the spherical shape 12c of the probe tip 12 is easily maintained.
Further, the operation of gradually pushing in suppresses a sudden reaction force change in the X, Y, and Z directions acting between the probe tip 12 and the polishing layer 51, so that the probe tip 12 sticks and slips on the polishing layer 51. Can be prevented.
As described above, the cleaning according to the first embodiment can effectively remove aluminum deposits when the probe tip 12 has a spherical shape and an inclined portion that extends straight from the middle of the spherical shape.

  As described above, in the first embodiment, the probe tip 12 is moved in the horizontal direction while continuously increasing the push of the probe 12 into the cleaning sheet 50 up to a predetermined push amount. The center 12a is in contact with the polishing layer 51 first. Thereafter, the amount of push-in increases, and the probe tip side portion 12b is cleaned, so that the probe tip portion center 12a can be polished more and the probe tip side portion 12b can be polished less, and the strength resulting from the probe tip portion 12 becoming thinner. This has the effect of preventing the probe 11 from being broken. Further, the deposit 13 at the probe tip center 12a is first removed, and the probe tip side 12b is gradually cleaned, so that the probe tip center 12a is prevented from being flattened, and the spherical shape 12c of the probe tip 12 is reduced. There is an effect that it is easy to maintain the profile, and accordingly, the yield of the production process is improved.

Embodiment 2. FIG.
Next, a second embodiment will be described.
FIG. 4 is a graph showing the trajectory of the probe tip 12 in the X and Z directions in a step-like continuous push-in increase.
In the first embodiment, the cleaning sheet 50 is moved in the X and Y directions while the probe tip 12 is continuously slightly increased in the Z direction. You may make it increase in a shape.
For example, when the probe tip 12 shown in the first embodiment is cleaned, if the probe 11 protruding from the holding portion 10a is moved in the horizontal direction while being pushed into the polishing layer 51 by 0.05 mm once, the probe 11 is moved in the horizontal direction. Although it is easy to stick-slip due to the reaction force of time, stick-slip can be prevented by increasing the pushing amount stepwise and continuously by 0.01 mm.
Thus, if the probe tip 12 receives from the polishing layer 51 the reaction force received from the polishing layer 51 is increased by a pushing amount so that the probe tip 12 does not change suddenly, the same effect can be obtained for removing the aluminum deposit 13 from the probe tip 12. Is obtained.

Embodiment 3 FIG.
Next, a third embodiment will be described.
FIG. 6 is a cross-sectional view of the probe jig 10 and the attachment 14 for explaining attachment 14 attachment. FIG. 6A shows a state where the attachment 14 is attached, and FIG. 6B shows a state where the attachment 14 is not attached.
In the first and second embodiments, the probe 11 is fixed to the probe cassette holder 20 with the probe 11 attached to the probe jig 10 as shown in FIGS. 1 and 6B. Accordingly, in FIG. 6B, for example, when the protruding amount from the holding portion 14a is as long as 0.5 mm or more with respect to the diameter of the probe 11 of 0.1 mm, stick-slip is likely to occur. In order to prevent this stick slip, the attachment 14 may be attached for the purpose of shortening the distance from the holding portion 14a to the probe distal end portion 12. The attachment 14 has a plate shape in which a hole is formed at the same position as the arrangement of the probe 11 of the probe jig 10 and regulates the displacement of the probe 11 in the horizontal direction.
This attachment 14 shortens the distance from the probe tip 12 to the holding portion 14a, and has an effect of preventing the occurrence of stick-slip of the probe 11 and the bending of the probe 11 during the cleaning operation.

10 probe jig, 10a holding part, 11 probe, 12 probe tip part,
13 attachments, 14 attachments, 23 Z-direction drive, 30 X stage,
32 X direction drive device, 40 Y stage, 42 Y direction drive device,
50 cleaning sheet, 51 polishing layer, 100 cleaning device.

Claims (5)

A probe cleaning device used for electrical property inspection,
The cleaning device is equipped with a probe provided with a spherical tip formed with a curvature R or a probe provided with a probe provided with an inclined portion extending straight from the middle of the spherical tip. A mechanism, a stage for fixing a cleaning sheet for removing foreign matter adhering to the probe tip, a horizontal drive mechanism for the stage, and a control device for controlling the vertical and horizontal drive mechanisms are provided. The controller controls the vertical driving mechanism until the probe tip is pushed into the cleaning sheet a plurality of times until the pushing amount continuously increases to a predetermined value, and the horizontal driving mechanism is controlled. Drive control of the direction drive mechanism so that the movement trajectory of the cleaning sheet relative to the probe tip is a continuous closed loop A cleaning device of the probe to said Rukoto. 2. The probe cleaning device according to claim 1, wherein the cleaning sheet is provided with a polishing layer on a surface thereof and an elastic-plastic material on a lower layer thereof. The control device performs drive control so that the tip of the probe is pushed into the cleaning sheet a plurality of times, and the amount of pushing is continuously increased to a predetermined value until it reaches a predetermined value. The probe cleaning apparatus according to claim 1. The vertical driving mechanism is provided with an attachment for adjusting a vertical distance between the cleaning sheet and a holding portion of the probe jig, and the probe is attached to the attachment. The probe cleaning device according to claim 1. A probe cleaning method using the probe cleaning apparatus according to claim 1.

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