JP2006023229A - Probe card quality evaluation method and apparatus, and probe inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe card quality evaluation method, an apparatus therefor, and a probe inspection method capable of bringing a probe pin of a probe card into contact with an electrode pad of a circuit element with good reproducibility.
After adjusting the position of a support stage by alignment, a probe pin is moved in a horizontal direction (X direction, Y direction) with respect to a surface on which an electrode pad is formed of an IC chip. The coordinate position of the support stage when 32 is dropped from the electrode pad 92 is obtained for each of the X direction and the Y direction. Next, the coordinate position range of the support stage 11 in which all the probe pins 32 can be brought into contact with the corresponding ones of the electrode pads 92 is determined from the obtained coordinate positions. Then, the center of the grasped coordinate position range is calculated and set as an optimum contact point.
[Selection] Figure 5

Description

  The present invention relates to a probe card quality evaluation method, an apparatus therefor, and a probe inspection method. In particular, the probe pin of a probe card can be brought into contact with an electrode pad of a circuit element with good reproducibility.

  Conventionally, a prober has been used as an inspection device for inspecting the electrical characteristics (resistance value, breakdown voltage, leakage current, output current, output voltage, threshold voltage, circuit operation, etc.) of an IC chip built in a wafer. Yes. This type of prober presses the probe pin of the probe card against the electrode pad of the IC chip built in the wafer according to a predetermined inspection program. The device automatically inspects the electrical characteristics of the IC chip by applying a predetermined test signal to the IC chip or detecting an output signal via the probe card.

In recent years, IC chips have been miniaturized and highly integrated, and the electrode pads of the IC chips are also becoming smaller.
FIG. 4A is a plan view showing an example of the arrangement of the electrode pads 92 in the IC chip 90. 4B and 4C are diagrams showing an example of a cross-sectional shape of the electrode pad 92. FIG. For example, the electrode pad 92 of the IC chip 90 has a rectangular shape in plan view as shown in FIG. 4A, and the size thereof is, for example, 20 [μm] in the vertical direction and 20 [μm] in the horizontal direction. It is getting smaller. There are several types of electrode pads 92. For example, as shown in FIG. 4B, the electrode pads 92 made of gold bumps having a substantially flat upper surface (hereinafter referred to as “gold bump pads”) or FIG. As shown in C), there is an aluminum electrode pad 92 made of an aluminum alloy whose upper surface is raised to some extent.

  With the progress of miniaturization and high integration of the IC chip 90, it is important to bring the probe pin into contact with the electrode pad 92 of the IC chip 90 with high accuracy in order to correctly perform the probe inspection using the prober. It is. For this reason, as the electrode pad 92 of the IC chip 90 becomes smaller, the accuracy required for alignment between the IC chip 90 and the probe card (hereinafter referred to as “alignment”) has been further increased.

The alignment is performed, for example, by a method as shown in any one of the following i) to iv).
i) In the prober, for example, a lower camera is provided on the stage side where the wafer is placed, and an upper camera is provided on the test head side where the probe card is set. A probe card is set on the test head, and a wafer is placed on the support stage. In this state, the lower camera acquires position information of the probe card in the X direction and the Y direction. Also, wafer position information is acquired by the upper camera. Then, alignment is performed based on these two pieces of position information.
ii) As in i), a lower camera and an upper camera are provided, and the position information of the probe card and the wafer in the X direction and the Y direction is acquired and alignment is performed. Further, the contact overdrive amount in the Z direction is grasped by an electrical contact test between the probe pin of the probe card and the wafer.
iii) Similar to ii), alignment is performed by acquiring positional information of the probe card and the wafer in the X direction and the Y direction, respectively. Furthermore, the amount of contact overdrive in the Z direction is determined by an electrical contact test. In addition to this, the probe pin is brought into contact with a predetermined area for needle trace confirmation, and the position (X direction, Y direction) of the needle trace in the area is recognized. From the result of this image recognition, the position (X direction, Y direction) of the tip of the probe pin is grasped. The alignment is corrected based on the grasped position of the tip of the probe pin.
iv) Alignment is performed while confirming with a human eye using a microscope.

In addition to the methods shown in i) to iv), a positioning-specific pad is provided on the wafer, and a positioning-specific probe pin is provided on the probe card. A method of alignment is known by monitoring whether or not the dedicated probe pin and the dedicated electrode pad are electrically connected during probe inspection (see, for example, Patent Documents 1 and 2).
JP-A-1-129432 JP-A-9-260443

However, the methods shown in i) and ii) have the following problems a) and b).
a) “Cannot cope with variations in the shape, position and pitch of the tip of the probe pin”
That is, a plurality of probe pins are attached to the probe card, but these probe pins have processing dimension errors. For this reason, even in a new initial state, the shape of the tip of the probe pin and the pitch interval of the probe pin vary to some extent.

Also, the probe pin is usually worn and deformed by repeated contact with the wafer, and the shape, size, position, etc. of its tip gradually change with respect to the initial state of the new product. End up. Conventionally, in order to cope with variations in the shape, size and pitch interval of new probe pin tips, and changes in the shape caused by their use, all probe pin tips are aligned with a camera during alignment. A method of capturing and acquiring the position information has also been examined. However, in such a method, it takes a long time for the imaging operation by the camera and the image processing.
b) “Cannot cope with displacement of the tip of the probe pin due to pressing.”
That is, in order to ensure electrical continuity between the probe pin of the probe card and the electrode pad formed on the wafer, the probe pin is brought into contact with the electrode pad on the wafer, and the probe pin is further connected to the electrode pad. It is necessary to press the side (i.e., overdrive in the Z direction). Due to the addition of this overdrive, the tip of the probe pin may move so as to slide on the electrode pad, and the position of the tip of the probe pin may change before and after the overdrive is added. . Further, the addition of the overdrive may cause the tip of the probe pin to protrude from the electrode pad.

Further, the method shown in iii) has problems as shown in c) below although the above a) and b) can be solved.
c) “In the second and subsequent alignments, the contact marks cannot be image-recognized correctly, and the alignment accuracy cannot be improved.”
That is, when the probe pin is contacted once in a predetermined area for checking the needle trace, and then this probe pin is contacted again in the same predetermined area, the previous and current contact traces are included in this predetermined area. Both will be left behind. For this reason, at the time of the second and subsequent contacts, there is a possibility that the image of the contact trace cannot be recognized correctly.

  In addition, when checking the contact trace with the gold bump pad 92 as shown in FIG. 4B, the gold bump pad 92 is harder than the material of the probe pin. Contact marks due to probe pins are difficult to remain. For this reason, an IC chip having a gold bump pad (hereinafter, also referred to as “circuit element”) has a problem that the contact trace cannot be image-recognized correctly.

Further, depending on the material of the probe pin, there is a case in which a contact mark is hardly left on the electrode pad even if it is not a gold bump pad. If the contact marks cannot be recognized correctly, the alignment accuracy cannot be improved.
Further, the method shown in iv) has a problem as shown in d) below.
d) “Miss and error are likely to occur.”
That is, the alignment performed while visually observing both the probe card and the wafer using a microscope is a harsh task for humans from the viewpoint of physical strength and concentration. For this reason, mistakes and errors are likely to occur.

  On the other hand, in the methods described in Patent Documents 1 and 2, a positioning dedicated probe pin (hereinafter referred to as “reference pin”) and a product measuring probe pin (hereinafter referred to as “actual measurement pin”) are provided. It is provided separately. For this reason, if the actual measurement pin is misaligned with respect to the reference pin, the actual measurement pin may not be in proper contact with the electrode pad even if the alignment is successful, and the probe inspection may not be performed correctly. there were.

  The present invention has been made paying attention to such an unsolved problem of the conventional technology, and can make the probe pin of the probe card contact the electrode pad of the circuit element with good reproducibility. It is an object of the present invention to provide a quality evaluation method and apparatus for a probe card, and a probe inspection method.

[Invention 1] In order to achieve the above object, a probe card quality evaluation method according to the present invention includes a probe having a plurality of probe pins respectively corresponding to a plurality of electrode pads of a circuit element to be subjected to probe inspection. A method of evaluating the quality of a card, the step of bringing each of the plurality of probe pins into contact with a corresponding one of the plurality of electrode pads, and at least one of the plurality of probe pins A first moving step of moving the probe card in a horizontal direction with respect to the electrode pad forming surface of the circuit element until the probe pin is separated from the corresponding electrode pad, and among the plurality of probe pins The probe card is moved until the at least one probe pin is separated from the corresponding electrode pad. A second movement step for moving in a direction opposite to the step; first timing information when at least one or more of the probe pins are separated from the corresponding electrode pads in the first movement step; and Obtaining at least one second timing information when at least one of the probe pins is separated from the corresponding electrode pad in the second moving step.

  Here, the first timing information and the second timing information may be either time information or position information. For example, when the first timing information is acquired in the form of time information, at least one probe pin corresponds to the probe card after the probe card starts to move in the horizontal direction with respect to the electrode pad formation surface of the circuit element. There is a method of measuring a time until the electrode pad is separated from the electrode pad and using the measured time as first timing information. In this case, it is necessary to keep the moving speed of the probe card constant.

When acquiring the first timing information in the form of position information, the probe card is moved in the horizontal direction with respect to the electrode pad forming surface of the circuit element, and at least one probe pin has the corresponding electrode. There is a method of measuring the position of the probe card when it is separated from the pad and using the measured position as first timing information.
Note that the movement of the probe card in the first movement step and the second movement step means a relative movement with respect to the circuit element. That is, either the circuit element or the probe card may be moved, and both the circuit element and the probe card may be moved. Alternatively, for example, when there is a support stage that supports the circuit element, the support stage that supports the circuit element may be moved with respect to the probe card.

  In addition, the circuit element used when evaluating the quality of the probe card may be a circuit element actually used for probe inspection (that is, a circuit element as a product), or a circuit element dedicated to quality evaluation instead of a product. good. When circuit elements dedicated to quality evaluation are used, those having the same number of electrode pads having the same shape and size at the same position as the product are selected and used.

  According to the probe card quality evaluation method of the first aspect of the present invention, each of the plurality of probe pins can be brought into contact with the corresponding one of the plurality of electrode pads based on the first and second timing information. Thus, the position range of the probe card (that is, the margin for alignment between the probe card and the circuit element) can be grasped, and the quality of the probe card can be evaluated from the magnitude of the grasped position range. It can be said that the larger the position range, the higher the quality of the probe card.

  Further, according to such a quality evaluation method for a probe card, the position range can be grasped, and the center of the position range can be calculated. Therefore, for example, in a probe inspection apparatus, after roughly adjusting the alignment between the probe card and the circuit element, a plurality of probes are corrected by correcting the position of the probe card so that the probe card comes to the center of the position range. Each pin can be brought as close to the center of the corresponding electrode pad as possible. As a result, the accuracy of alignment between the probe card and the circuit element can be improved, and each of the plurality of probe pins can be brought into contact with the corresponding one of the plurality of electrode pads with high reproducibility. .

[Invention 2] The probe card quality evaluation method according to Invention 2 is the probe card quality evaluation method according to Invention 1, wherein the plurality of probe pins are based on the first timing information and the second timing information. And calculating a position range of the probe card that can contact each of the plurality of electrode pads with a corresponding one of the plurality of electrode pads. With such a configuration, the quality of the probe card can be evaluated from the size of the calculated position range.

[Invention 3] The probe card quality evaluation method of Invention 3 is the probe card quality evaluation method of Invention 1 or Invention 2, for each of a plurality of mutually intersecting directions determined by the shape of the electrode pad in plan view. The first moving step and the second moving step are performed.

  According to the probe card quality evaluation method of the third aspect of the present invention, the position ranges of the probe cards in which each of the plurality of probe pins can be brought into contact with the corresponding one of the plurality of electrode pads are mutually viewed in plan view. Each of a plurality of intersecting directions can be calculated. Therefore, the quality of the probe card can be evaluated more correctly. The position of the probe card can be corrected in the vertical direction and the horizontal direction in plan view.

[Invention 4] The probe card quality evaluation method of Invention 4 is the probe card quality evaluation method of Invention 3, wherein when the shape of the electrode pad in a plan view is a rectangle, the plurality of directions are One direction parallel to the upper and lower sides of the rectangle and another direction parallel to the left and right sides of the rectangle.

  With such a configuration, the position range of the probe card capable of bringing each of the plurality of probe pins into contact with the corresponding one of the plurality of electrode pads is set to be parallel to the upper and lower sides of the rectangle. And the other direction parallel to the left and right sides of the rectangle.

[Invention 5] The probe card quality evaluation method according to Invention 5 is the probe card quality evaluation method according to Invention 3, wherein when the shape of the electrode pad in a plan view is circular, the plurality of directions are orthogonal to each other. It is characterized by two directions.
With such a configuration, the position range of the probe card capable of bringing each of the plurality of probe pins into contact with the corresponding one of the plurality of electrode pads is calculated for each of two orthogonal directions. can do.

[Invention 6] The probe card quality evaluation method according to Invention 6 is the probe card quality evaluation method according to any one of Inventions 1 to 5, wherein the first moving step and the second moving step include the plurality of probe card quality evaluation methods. The probe card is moved while the tip of the probe pin is brought into contact with the electrode pad at a certain timing, and the tip is separated from the electrode pad at other timings. is there. Here, the fixed timing is, for example, a fixed time or a fixed distance.

  According to the quality evaluation method of the probe card of the invention 6, the chance of contact between the probe pin and the electrode pad can be reduced, and wear and deformation of the probe pin due to contact with the electrode pad can be suppressed. Further, when the electrode pad is made of a conductive member that is softer than the probe pin, such as an aluminum alloy, the surface of the electrode pad due to the contact can be prevented from being scraped or peeled off.

[Invention 7] The probe card quality evaluation method of Invention 7 is an apparatus for evaluating the quality of a probe card having a plurality of probe pins respectively corresponding to a plurality of electrode pads of a circuit element subjected to probe inspection. A contact means for bringing each of the plurality of probe pins into contact with a corresponding one of the plurality of electrode pads, and at least one of the plurality of probe pins corresponds to the contact means. A first moving means for moving the probe card in a horizontal direction with respect to the electrode pad forming surface of the circuit element until it is separated from the electrode pad; and at least one of the plurality of probe pins. The probe card is moved in the opposite direction to the first moving process until the electrode card moves away from the corresponding electrode pad. Second moving means to be used, first timing information when at least one probe pin is separated from the corresponding electrode pad in the first moving step, and at least one in the second moving step. Based on the information acquisition means for acquiring the second timing information when the probe pins more than or equal to the corresponding electrode pad are separated, the first timing information and the second timing information, Calculating means for calculating a position range of the probe card capable of bringing each of a plurality of probe pins into contact with a corresponding one of the plurality of electrode pads. .

With such a configuration, the quality of the probe card can be evaluated from the size of the calculated position range.
Further, according to such a quality evaluation apparatus for a probe card, the center of the position range can be calculated. Therefore, for example, in a probe inspection apparatus, after roughly adjusting the alignment between the probe card and the circuit element, a plurality of probes are corrected by correcting the position of the probe card so that the probe card comes to the center of the position range. Each pin can be brought as close to the center of the corresponding electrode pad as possible. As a result, the accuracy of alignment between the probe card and the circuit element can be improved, and each of the plurality of probe pins can be brought into contact with the corresponding one of the plurality of electrode pads with high reproducibility. .
The probe card quality evaluation method and the probe card quality evaluation apparatus according to the first to seventh aspects of the present invention can be applied to a probe card manufacturing process for manufacturing a probe card or a probe card inspection process for inspecting a probe card itself. Is preferred.

[Invention 8] The probe inspection method of Invention 8 includes a stage for mounting a circuit element, and a probe card having a plurality of probe pins respectively corresponding to a plurality of electrode pads of the circuit element. The probe card quality evaluation method according to any one of the inventions 1 to 6 is performed when the circuit element is probe-inspected using a probe inspection apparatus.

If it is such composition, based on the 1st and 2nd timing information, the position of the probe card which can make each of a plurality of probe pins contact the corresponding thing among a plurality of electrode pads The range can be grasped, and the center of the grasped position range can be calculated.
Accordingly, after roughly adjusting the alignment between the probe card and the circuit element, the probe card is corrected so that the probe card is positioned at the center of the position range, so that a plurality of probe pins correspond to each other. It is possible to make contact as close to the center of the electrode pad as possible. As a result, the accuracy of alignment between the probe card and the circuit element can be improved, and each of the plurality of probe pins can be brought into contact with the corresponding one of the plurality of electrode pads with high reproducibility. .

  The probe inspection method of the invention 8 is extremely suitable when applied to, for example, a manufacturing process of an IC chip built in a wafer or a probe inspection process of an IC chip.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1A and 1B are conceptual diagrams showing a configuration example of a prober 100 according to an embodiment of the present invention. The prober 100 is an inspection device for inspecting the electrical characteristics of an IC chip 90 (see FIG. 4A) built in a semiconductor wafer W.
As shown in FIG. 1A, the prober 100 includes a support stage 11 for mounting a semiconductor wafer (hereinafter simply referred to as a wafer), and a housing of the prober 100 above the support stage 11. The test head 13 is fixed to the test head 13, the probe card 30 is detachably attached to the test head 13, and the camera bridge 16 is installed obliquely above the support stage 11. The prober 100 also includes an upper camera 17 attached to the camera bridge 16 and a lower camera 19 attached to the side of the support stage 11 below the probe card 30.

Further, as shown in FIG. 1B, the prober 100 includes an X-direction moving stage 23 that can move along the X-axis 21 and a Y-direction moving stage 27 that can move along the Y-axis 25. ing. The prober 100 also includes an alignment mechanism 50 (see FIG. 3) including the test head 13, the upper camera 17, the lower camera 19, and the like.
In this embodiment, the vertical direction with respect to the wafer placement surface of the support stage 11 is referred to as the Z direction, and the horizontal direction with respect to the wafer placement surface of the support stage 11 is referred to as the X direction and the Y direction. The support stage 11 can be moved up and down in the Z direction, and can rotate (that is, rotate in the θ direction) about a support shaft 11a along the Z direction. The support stage 11 is made of a metal that is a good conductor of electricity and heat, for example, and is connected to the ground.

The test head 13 shown in FIG. 1 (A) outputs a predetermined electrical signal to the probe card 30 according to a predetermined inspection program, or receives a return electrical signal, so that the electrical power of the IC chip built into the wafer W is obtained. It measures the physical characteristics.
FIG. 2 is a plan view showing a configuration example of the probe card 30. As shown in FIG. 2, the probe card 30 is provided with a plurality of probe pins 32 on a printed circuit board 31. The arrangement of the probe pins 32 in the probe card 30 corresponds to the arrangement of the electrode pads 92 (see FIG. 4A) of the IC chip 90 to be inspected.

Returning to FIG. 1A, the upper camera 17 includes, for example, a low-power lens and a high-power lens, and both the lenses are directed to the support stage 11 and the like that are obliquely below the camera bridge 16. . Here, the low magnification lens is, for example, a lens with 10 to 50 magnification, and the high magnification lens is, for example, a lens with 100 to 200 magnification.
In the prober 100, the coordinate position of the support stage 11 and the wafer W in the X direction and the Y direction is acquired by photographing the wafer W on the support stage 11 with the upper camera 17. ing. Further, in the prober 100, when the focus (focus) of the upper camera 17 is focused on a lattice pattern (not shown) engraved on the entire surface of the support stage 11, the periphery of the support stage 11, or the like. The coordinate position of the support stage 11 and the wafer W in the Z direction is acquired from the focal length of the wafer. The upper camera 17 is, for example, a CCD (charge coupled device) camera.

As shown in FIG. 1A, the lower camera 19 is mounted on the X-direction moving stage 23 on the side of the support stage 11. The lower camera 19 is composed of a low-magnification camera and a high-magnification camera, and recognizes the position of the probe pin and the like from the X-direction moving stage 23. The lower camera 19 is, for example, a CCD camera.
Further, the X-direction moving stage 23 supports the support stage 11 and the lower camera 19 from below, and the support stage 11 and the lower camera 19 are moved along the X axis 21 as shown in FIG. Are moved together. The Y-direction moving stage 27 supports the X-axis 21 and the X-direction moving stage 23 from the lower side, and moves the X-axis 21 and the X-direction moving stage 23 integrally along the Y-axis 25. is there. The support stage 11 moves in the X direction and the Y direction by combining the movement operation of the X-direction movement stage 23 by the drive system and the movement operation of the Y-direction movement stage 27 by the drive system.

  The support stage 11 can be moved in the Z direction as described above by a drive system that moves the support shaft 11a up and down in the vertical direction. Hereinafter, the X-direction moving stage 23 and its drive system, the Y-direction moving stage 27 and its drive system, and the drive system for moving the support shaft 11a and the support shaft 11 up and down are collectively referred to as a “stage moving mechanism”. . By this stage moving mechanism, the support stage 11 can be moved in the X direction, the Y direction, and the Z direction.

  FIG. 3 is a block diagram illustrating a configuration example of the alignment mechanism 50. The alignment mechanism 50 aligns the IC chip 90 and the probe card 30 when the probe inspection is performed on the IC chip 90 (see FIG. 4A) built in the wafer W. By aligning with the alignment mechanism 50, a corresponding one of the plurality of probe pins 32 of the probe card 30 is placed on each of the electrode pads 92 (see FIG. 4A) of the IC chip 90. It becomes possible to make it contact.

  As shown in FIG. 3, the alignment mechanism 50 includes a test head 13, a probe card 30, an upper camera 17, a lower camera 19, a stage moving mechanism 40, a control unit 42, a data storage unit 44, and the like. It is composed of Among these, the test head 13, the probe card 30, the upper camera 17, the lower camera 19, and the stage moving mechanism 40 are as described above.

  The control unit 42 is, for example, a CPU (central processing unit). The control unit 42 is connected to the test head 13, the probe card 30, the upper camera 17, the lower camera 19, the stage moving mechanism 40, the data storage unit 44, and the like, and functions to control overall operations related to alignment. And a predetermined calculation function. Furthermore, the data storage unit 44 is, for example, a RAM (Random Access Memory). The data storage unit 44 stores an operation program related to alignment. Further, the data storage unit 44 stores position information of the support stage 11 in the X, Y, and Z directions obtained by the upper camera 17, probe pin position information obtained by the lower camera 19, and the like.

In the prober 100, the control unit 42 is connected to, for example, an interface (I / F) of the test head 13, and controls the upper camera 17, the lower camera 19, the stage moving mechanism 40, and the like via the test head 13. It has become.
FIG. 8 is a flowchart (main routine) showing a probe inspection method using the prober 100. Next, when the IC chip 90 built in the wafer W is probe-inspected using the above-described prober 100, the probe card 30 and the IC chip 90 are aligned (aligned). FIGS. 1A and 1B, FIG. 3, FIG. 4A to FIG. 4C, and FIGS. 1A to 1C show fine adjustment of the alignment in accordance with the shape of the tip, its position, variation in pitch, and the like. Description will be made with reference to FIGS.

  Here, before starting the flowchart shown in FIG. 8, the conventional alignment method is performed by the prober 100 so that all the probe pins 32 of the probe card 30 correspond to the electrode pads 92 of the IC chip 90. It is assumed that the contact accuracy is coarsely adjusted in advance so as to make contact with each other. As a conventional alignment method, for example, there is the method i) or ii) mentioned in the section of “Background Art”. After roughly adjusting the contact accuracy, the flowchart of FIG. 8 is started.

In step S <b> 1 of FIG. 8, first, the stage moving mechanism 40 is operated under the control of the control unit 42 to raise the support stage 11, thereby moving the support stage 11 to a normal contact height. Next, the process proceeds to step S2 in FIG.
FIG. 9 is a subroutine showing an example of determining the Z position of the support stage 11 (step S2). Here, the Z position is a coordinate position of the support stage 11 in the Z direction (that is, a direction perpendicular to the wafer mounting surface).

  In Step A1 of FIG. 9, first, a continuity test (ie, a contact test) is performed between the probe card 30 and the IC chip 90. Next, in step A2 of FIG. 9, it is determined whether or not the probe card 30 and the IC chip 90 are in proper contact. This determination is made by the control unit 42 based on, for example, the result of the contact test sent from the test head 13. If it is determined in step A2 that the contact test has passed, the process proceeds to step A3 in FIG. On the other hand, if it is determined as unacceptable, the process proceeds to step A7 in FIG.

  In step A3, the stage moving mechanism 40 is operated under the control of the control unit 42 to raise the support stage 11 by a predetermined height (addition of overdrive). Thereby, the probe pin 32 of the probe card 30 is pressed onto the electrode pad 92 of the IC chip 90, and the probe pin 32 and the electrode pad 92 are brought into close contact with each other. Next, the process proceeds to step A4 in FIG. In step A4, it is determined whether or not the height of the support stage 11 after the overdrive is added (that is, the coordinate position in the Z direction) exceeds a specified value (limit).

This determination is performed by the control unit 42 based on, for example, the position information in the Z direction of the support stage 11 sent from the upper camera 17 and the specified value in the Z direction stored in the data storage unit 44. If the height of the support stage 11 exceeds the specified value, the process proceeds to step A10 in FIG. If not, the process proceeds to step A5 in FIG.
In step A5, the same contact test as in step A1 is performed. Then, after the contact test, the process proceeds to step A6 in FIG. In step A6, it is determined whether or not the probe card 30 and the IC chip 90 are in proper contact. This determination is performed by the control unit 42, for example.

If it is determined in step A6 that the contact test has been passed, the coordinate position in the Z direction of the support stage 11 after the overdrive is added is stored in the data storage unit 44 as a correction value, and as shown in FIG. Exit the subroutine. Here, it is assumed that the correction value is, for example, Z = + 2 [μm]. On the other hand, if it is determined to be unacceptable, the process proceeds to step A11 in FIG.
On the other hand, in step A7, it is determined whether or not the height of the support stage 11 exceeds a specified value. This determination is performed by the control unit 42, for example. If the height of the support stage 11 exceeds the specified value, the process proceeds to step A8 in FIG. If not, the process proceeds to step A9 in FIG. In step A9, the support stage 11 is raised by, for example, 2 [μm], and then the process returns to step A1. In steps A8, A10, and A11, for example, an alarm is generated from the prober 100 to notify the operator or the like of the abnormality. At the same time, the subroutine of FIG. 9 is exited and the flowchart of FIG. 8 is terminated.

After determining the Z position of the support stage 11 in step S2 of FIG. 8, the process proceeds to step S3 of FIG.
FIG. 10 is a subroutine showing an example of determining the X position of the support stage 11 (step S3). Here, the X position is a coordinate position of the support stage 11 in the X direction (that is, horizontal and horizontal with respect to the wafer mounting surface).

  In Step B1 of FIG. 10, first, a contact test is performed between the probe card 30 and the IC chip 90. In step B1, the coordinate position in the X direction of the support stage 11 when the probe card 30 and the IC chip 90 are first brought into contact with each other is defined as an “X origin position”. Next, in step B2 of FIG. 10, it is determined whether or not the probe card 30 and the IC chip 90 are correctly in contact. This determination is made by the control unit 42 based on, for example, the result of the contact test sent from the test head 13.

  If it is determined in step B2 that the contact test has passed, the process proceeds to step B8 in FIG. On the other hand, if it is determined to be unacceptable, the process proceeds to step B3 in FIG. In Step B8, it is determined whether or not the coordinate position of the support stage 11 in the X direction (that is, the left-right direction) exceeds a specified value. This determination is performed by the control unit 42 based on, for example, the position information in the X direction of the support stage 11 sent from the upper camera 17 and the specified value in the X direction stored in the data storage unit 44.

When the coordinate position of the support stage 11 in the X direction exceeds the specified value, the process proceeds to Step B3 in FIG. If not, the process proceeds to step B9 in FIG. In step B9 in FIG. 10, the support stage 11 is moved 2 [μm], for example, leftward from the X origin position.
FIG. 6 is a conceptual diagram showing an example of the movement operation of the probe pin 32. 6, the support stage 11 when a to X home position, with all the probe pins 32 points P _0, it is assumed that contact with the electrode pads 92 corresponding respectively. If the shape, size, pitch, and the like of the probe pins 32 are completely uniform within the probe card 30 and the alignment between the probe card 30 and the IC chip 90 is also perfect, the points for each electrode pad 92 will be described. The position of P ₀ is also uniform. However, in practice, the shape, size, pitch, and the like of the probe pins 32 usually vary to some extent as the frequency of use increases. For this reason, the position of the point P ₀ is slightly different between the electrode pads 92 as shown in FIG.

In step B9, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved 2 μm leftward. Then, the support stage 11 is raised by a predetermined distance in the Z direction, and all the probe pins 32 and the corresponding electrode pads 92 are brought into contact with each other. As a result, all the probe pins 32 can be moved from the point P ₀ to the point P _X-2 without damaging the electrode pad 92 so much.

Next, returning to step B1, the contact test is performed in a state where all the probe pins 32 are moved to the point PX _-2 . In step B2, it is determined whether or not the contact test is passed.
In this embodiment, it is assumed that each of the processes of steps B1, B2, B8, and B9 is performed a plurality of times and then the process proceeds to step B3 in the subroutine shown in FIG. For example, when the support stage 11 is moved 6 [μm] leftward and all the probe pins 32 are moved to the point PX _-6 as shown in FIG. Suppose that it sticks out. The result is stored in the data storage unit 44 (see FIG. 3). Next, the process proceeds from step B2 to step B3.

In step B3, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved to the X origin position. Next, the process proceeds to step B4 in FIG.
In step B4, a contact test is performed between the probe card 30 and the IC chip 90. Then, in step B5 of FIG. 10, it is determined whether or not the probe card 30 and the IC chip 90 are correctly in contact. This determination is performed by the control unit 42, for example.

  If it is determined in step B5 that the contact test has passed, the process proceeds to step B10 in FIG. In step B10, it is determined whether or not the coordinate position of the support stage 11 in the X direction exceeds a specified value. This determination is performed by the control unit 42, for example. When the coordinate position of the support stage 11 in the X direction exceeds the specified value, the process proceeds to Step B6 in FIG. If not, the process proceeds to Step B11 in FIG.

In step B11, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved 2 μm rightward. Then, the support stage 11 is raised by a predetermined distance in the Z direction, and all the probe pins 32 and the corresponding electrode pads 92 are brought into contact with each other. Thereby, all the probe pins 32 can be moved from the point P ₀ to PX ₂ without damaging the electrode pad 92 so much.

Next, returning to step B4, the contact test is performed in a state where all the probe pins 32 have moved to the point _PX2 . In step B5, it is determined whether or not the contact test is passed.
In this embodiment, a case is assumed in which the processes in steps B4, B5, B10, and B11 are performed a plurality of times and then the process proceeds to step B6 in the subroutine shown in FIG. For example, when the support stage 11 is moved 8 [μm] to the right and all the probe pins 32 are moved to the point _PX8 as shown in FIG. 6, some of the probe pins 32 protrude from the electrode pad 92. Suppose. The result is stored in the data storage unit 44 (see FIG. 3). Next, the process proceeds from step B5 to step B6.

In step B6, the coordinate position range in the X direction of the support stage 11 that brings all the probe pins 32 into contact with the corresponding ones of the electrode pads 92 is calculated. The center of the coordinate position range in the X direction is set as an optimum contact point in the X direction.
FIG. 7 is a diagram illustrating a method for calculating the optimum contact point. The horizontal axis in FIG. 7 indicates the X origin position, and the vertical axis indicates the Y origin position described later.

As described above, in steps B1, B2, B3, B8, and B9 of the subroutine shown in FIG. 10, for example, the support stage 11 is moved 6 [μm] leftward, and all the probe pins 32 are moved to the point P _X-6. Some probe pins 32 protruded from the electrode pads 92 when moved to the position. Therefore, in FIG. 7, the left end of the coordinate position range in the X direction is set to −4 [μm]. In steps B4, B5, B3, B10, and B11, for example, when the support stage 11 is moved 8 [μm] leftward and all the probe pins 32 are moved to the point _PX8 , some of the probe pins 32 protruded from the electrode pad 92. Therefore, in FIG. 7, the right end of the coordinate position range in the X direction is set to +6 [μm].

As shown in FIG. 7, the coordinate position range in the X direction of the support stage 11 is −4 ≦ X ≦ 6. The center is X = + 1 [μm]. From such a result, the correction value in the X direction is set to +1 [μm]. This arithmetic processing is performed by the control unit 42 based on, for example, the arithmetic processing program stored in the data storage unit 44 and the result of the contact test.
In step B7 in FIG. 10, the position of the support stage 11 is corrected based on the result of the arithmetic processing in step B8. In this embodiment, since the correction value in the X direction is +1 [μm] as described above, the support stage 11 is moved to the right by 1 μm from the X origin position. This completes the subroutine of FIG.

After the X position of the support stage 11 is determined in step S3 in FIG. 8, the process proceeds to step S4 in FIG.
FIG. 11 is a subroutine showing an example of determining the Y position of the support stage 11 (step S4). Here, the Y position is a coordinate position of the support stage 11 in the Y direction (that is, horizontal with respect to the wafer mounting surface and in the vertical direction).

  In step C <b> 1 of FIG. 11, first, a contact test is performed between the probe card 30 and the IC chip 90. In this step C1, the coordinate position in the Y direction of the support stage 11 when the probe card 30 and the IC chip 90 are first brought into contact with each other is defined as “Y origin position”. Next, in step C2 of FIG. 11, it is determined whether or not the probe card 30 and the IC chip 90 are correctly in contact. This determination is made by the control unit 42 based on, for example, the result of the contact test sent from the test head 13.

  If it is determined in step C2 that the contact test has passed, the process proceeds to step C8 in FIG. On the other hand, if it is determined to be unacceptable, the process proceeds to step C3 in FIG. In step C8, it is determined whether or not the coordinate position of the support stage 11 in the Y direction (that is, the vertical direction) exceeds a specified value. This determination is performed by the control unit 42 based on, for example, the position information in the Y direction of the support stage 11 sent from the upper camera 17 and the specified value in the Y direction stored in the data storage unit 44.

If the coordinate position in the Y direction of the support stage 11 exceeds the specified value, the process proceeds to step C3 in FIG. If not, the process proceeds to step C9 in FIG. In Step C9 of FIG. 11, the support stage 11 is moved 2 [μm], for example, upward from the Y origin position.
In FIG. 6, when the support stage 11 is at the Y origin position, all the probe pins 32 are in contact with the corresponding electrode pads 92 at the point P ₀ .

In Step C9, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved upward by 2 μm. Then, the support stage 11 is raised by a predetermined distance in the Z direction, and all the probe pins 32 and the corresponding electrode pads 92 are brought into contact with each other. Thus, without damaging the electrode pad 92 so, it is possible to move all the probe pins 32 from point P ₀ to point P _Y2.

Next, returning to step C1, the contact test is performed with all the probe pins 32 moved to the point _PY2 . In step C2, it is determined whether or not the contact test is passed.
In this embodiment, it is assumed that each of the processes in steps C1, C2, C8, and C9 is performed a plurality of times and then the process proceeds to step C3 in the subroutine shown in FIG. For example, when the support stage 11 is moved 4 [μm] upward and all the probe pins 32 are moved to the point _PY4 as shown in FIG. 6, some of the probe pins 32 protrude from the electrode pad 92. Suppose. The result is stored in the data storage unit 44 (see FIG. 3). Next, the process proceeds from step C2 to step C3.

In Step C3, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved to the Y origin position. Next, the process proceeds to step C4 in FIG.
In step C4, a contact test is performed between the probe card 30 and the IC chip 90. Then, in step C5 of FIG. 11, it is determined whether or not the probe card 30 and the IC chip 90 are correctly in contact. This determination is performed by the control unit 42, for example.

  If it is determined in step C5 that the contact test has passed, the process proceeds to step C10 in FIG. In step C10, it is determined whether or not the coordinate position in the Y direction of the support stage 11 exceeds a specified value. This determination is performed by the control unit 42, for example. When the coordinate position of the support stage 11 in the Y direction exceeds the specified value, the process proceeds to Step C6 in FIG. If not, the process proceeds to step C11 in FIG.

In step C11, for example, the support stage 11 is once lowered in the Z direction by a predetermined distance, and all the probe pins 32 and the corresponding electrode pads 92 are separated. Next, the support stage 11 is moved 2 μm downward. Then, the support stage 11 is raised by a predetermined distance in the Z direction, and all the probe pins 32 and the corresponding electrode pads 92 are brought into contact with each other. Thus, without damaging the electrode pad 92 so, it is possible to move all of the probe pins 32 from point P ₀ to P _Y-2.

Next, returning to step C4, the contact test is performed in a state where all the probe pins 32 have moved to the point _PY-2 . In step C5, it is determined whether or not the contact test is passed.
In this embodiment, it is assumed that each of the processes in steps C4, C5, C10, and C11 is performed a plurality of times and then the process proceeds to step C6 in the subroutine shown in FIG. For example, when the support stage 11 is moved downward 6 [μm] and all the probe pins 32 are moved to the point _PY-6 as shown in FIG. Suppose that it sticks out. The result is stored in the data storage unit 44 (see FIG. 3). Next, the process proceeds from step C5 to step C6.

In step C6, the coordinate position range in the Y direction of the support stage 11 that brings all the probe pins 32 into contact with the corresponding ones of the electrode pads 92 is calculated. The center of the coordinate position range in the Y direction is set as the optimum contact point in the Y direction.
As described above, in steps C1, C2, C3, C8, and C9 of the subroutine shown in FIG. 11, for example, the support stage 11 is moved upward by 4 [μm], and all the probe pins 32 are moved to the point _PY4. At that time, some of the probe pins 32 protruded from the electrode pad 92. Therefore, in FIG. 7, the upper end of the coordinate position range in the Y direction is set to +2 [μm]. In steps C4, C5, C3, C10, and C11, for example, when the support stage 11 is moved downward 6 [μm] and all the probe pins 32 are moved to the point _PY-6 , some The probe pin 32 protruded from the electrode pad 92. Therefore, in FIG. 7, the lower end of the coordinate position range in the Y direction is set to −4 [μm].

As shown in FIG. 7, the coordinate position range in the Y direction of the support stage 11 is −4 ≦ Y ≦ 2. The center is Y = −1 [μm]. From such a result, the correction value in the Y direction is set to −1 [μm]. This arithmetic processing is performed by the control unit 42 based on, for example, the arithmetic processing program stored in the data storage unit 44 and the result of the contact test.
In step C7 in FIG. 11, the position of the support stage 11 is corrected based on the result of the arithmetic processing in step C8. In this embodiment, since the correction value in the Y direction is −1 [μm] as described above, the support stage 11 is moved 1 μm downward from the Y origin position. This completes the subroutine of FIG.

After determining the Y position of the support stage 11 in step S3 in FIG. 8, the process proceeds to step S5 in FIG.
In step S <b> 5 of FIG. 8, all correction values (X, Y, Z) are stored in the data storage unit 44. As described above, in this embodiment, since (X, Y, Z) = (1, −1, 2) is obtained as the correction value, this value is stored in the data storage unit 44. Next, in step S9 of FIG. 9, based on the correction value stored in the data storage unit 44, the coordinate position of the support stage 11 is +1 in the X direction and −1 in the Y direction from the origin after alignment (coarse adjustment). , Move in the Z direction by +2. Thereafter, probe inspection is started.

  As described above, according to the probe inspection method according to the embodiment of the present invention, after the position of the support stage 11 is adjusted by alignment, the probe pin 32 is attached to the IC chip 90 as shown by the solid line arrow in FIG. It is moved in the horizontal direction (X direction, Y direction) with respect to the electrode pad 92 formation surface, and the coordinate position of the support stage when the probe pin 32 falls from the electrode pad 92 is obtained in the X direction and Y direction, respectively. Next, the coordinate position range of the support stage 11 in which all the probe pins 32 can be brought into contact with the corresponding ones of the electrode pads 92 is determined from the obtained coordinate positions. Then, the center of the grasped coordinate position range is calculated and set as an optimum contact point.

  Therefore, after roughly adjusting the alignment between the probe card 30 and the IC chip 90, the position of the support stage 11 is corrected so that the support stage 11 comes to the optimum contact point, so that all the probe pins 32 are moved. Each can be brought as close to the center of the corresponding electrode pad 92 as possible. As a result, the alignment accuracy between the probe card 30 and the IC chip 90 can be improved, and each of all the probe pins 32 can be brought into contact with the corresponding one of the electrode pads 92 with high reproducibility. .

  In addition, the quality evaluation method of the probe card 30 according to the embodiment of the present invention evaluates the quality of the probe card 30 having the probe pins 92 respectively corresponding to the plurality of electrode pads 92 of the IC chip 90 used for probe inspection. A method in which all of the probe pins 32 are brought into contact with corresponding ones of the electrode pads 92, and at least one of the probe pins 92 includes the corresponding electrode pads. A first moving step of moving the support stage 11 in the X direction and the Y direction with respect to the electrode pad 92 forming surface of the IC chip 90 until it is separated from the 92, and at least one of the probe pins 92 among the probes. Until the pins 92 are separated from the corresponding electrode pads 92, the support stage 11 is moved away from the first moving step. , That is, the support stage 11 when at least one probe pin 92 moves away from the corresponding electrode pad 92 in the second movement step of moving in the -X direction and -Y direction, and the first movement step. And the step of acquiring the coordinate position of the support stage 11 when at least one or more probe pins 92 move away from the corresponding electrode pad 92 in the second moving step.

Furthermore, the quality evaluation apparatus for the probe card 30 according to the embodiment of the present invention is an apparatus that realizes the above-described quality evaluation method, and includes, for example, the alignment mechanism 50 shown in FIG.
According to the quality evaluation method of the probe card 30 and the quality evaluation device of the probe card 30 according to the embodiment of the present invention, all the probe pins 32 can be brought into contact with the corresponding ones of the electrode pads 92, respectively. The coordinate position range of the support stage 11 in the X direction and the Y direction can be grasped, and the quality of the probe card 30 can be evaluated from the magnitude of the grasped coordinate position range of the support stage 11.

When the quality of the probe card 90 is evaluated by the quality evaluation method or the quality evaluation apparatus, it can be said that the quality of the probe card 30 is higher as the coordinate position range of the support stage 11 is larger.
In this embodiment, the IC chip corresponds to the circuit element of the present invention, and the alignment mechanism 50 corresponds to the apparatus for evaluating the quality of the probe card 30 of the present invention. The upper camera 17, the lower camera 19, the stage moving mechanism 40, the control unit 42, and the data storage unit 44 correspond to the contact means of the present invention. Furthermore, the test head 13, the stage moving mechanism 40, the control unit 42, and the data storage unit 44 correspond to the first and second moving means of the present invention. The test head 13 and the control unit 42 correspond to the information acquisition unit of the present invention, and the control unit 42 and the data storage unit 44 correspond to the calculation unit of the present invention.

  Further, when the support stage 11 is moved to the left or upward, the coordinate position information of the support stage 11 when a part of the probe pins 32 protrudes from the electrode pad 92 (that is, X = −6 [μm]). , Or Y = 4 [μm]) corresponds to the first timing information of the present invention. When the support stage 11 is moved to the right or downward, the coordinate position information of the support stage 11 when a part of the probe pins 32 protrudes from the electrode pad 92 (that is, X = 8 [μm], or Y = −6 [μm]) corresponds to the second timing information of the present invention.

  In this embodiment, the electrode pad 92 has a rectangular shape in plan view. However, the shape of the electrode pad 92 in plan view is not limited to a rectangle, and may be, for example, a circle. In this case, after the position of the support stage 11 is adjusted by alignment, the probe pin 32 is moved in each of two directions that are horizontal to and perpendicular to the electrode pad 92 forming surface of the IC chip 90. Thus, the coordinate position of the support stage when the probe pin 32 falls from the electrode pad 92 may be obtained for the X direction and the Y direction, respectively.

  As in the case where the shape of the electrode pad 92 in plan view is rectangular, by calculating the optimum contact point, each probe pin 32 is brought into contact with the corresponding one of the electrode pads 92 with high reproducibility. It is possible.

The conceptual diagram which shows the structural example of the prober 100 which concerns on embodiment of this invention. The top view which shows the structural example of the probe card 30. FIG. FIG. 3 is a block diagram illustrating a configuration example of an alignment mechanism 50. FIG. 3 is a plan view showing an example of the arrangement of electrode pads 92 in the IC chip 90. The conceptual diagram which shows the search method of a coordinate position range. The conceptual diagram which shows an example of the movement operation | movement of the probe pin 32. FIG. The figure which shows the calculation method of an optimal contact point. The flowchart (main routine) which shows the probe test | inspection method using the prober 100. FIG. The subroutine which shows an example of Z position determination (step S2) of the support stage 11. FIG. The subroutine which shows an example of X position determination (step S3) of the support stage 11. FIG. The subroutine which shows an example of Y position determination (step S4) of the support stage 11.

Explanation of symbols

  10 chuck stage, 20 heater, 30 probe card, 32 probe pin, 40 card holder, 50 test head, 60, 60 'temperature sensor, 70 stage moving mechanism, 72 Z direction drive shaft, 74 X direction moving stage, 76 Y direction Moving stage, 80 housing, 90 controller, 95 data storage, 100, 100 'prober, a, b, c, d, e, f, g position (temperature measured position by temperature sensor 60 or 60') , W Waha

Claims (8)

A method for evaluating the quality of a probe card having a plurality of probe pins respectively corresponding to a plurality of electrode pads of a circuit element subjected to probe inspection,
Contacting each of the plurality of probe pins with a corresponding one of the plurality of electrode pads;
The probe card is moved in the horizontal direction with respect to the electrode pad forming surface of the circuit element until at least one of the plurality of probe pins is separated from the corresponding electrode pad. Moving process;
A second moving step of moving the probe card in a direction opposite to the first moving step until at least one of the plurality of probe pins is separated from the corresponding electrode pad; ,
First timing information when at least one of the probe pins is separated from the corresponding electrode pad in the first movement step, and at least one of the probe pins is in the second movement step. Obtaining the second timing information when leaving the corresponding electrode pad. A method for evaluating the quality of a probe card.   The probe card capable of bringing each of the plurality of probe pins into contact with a corresponding one of the plurality of electrode pads based on the first timing information and the second timing information. The method for evaluating the quality of a probe card according to claim 1, further comprising: calculating a position range. For each of a plurality of directions intersecting each other determined by the shape of the electrode pad in plan view,
The quality evaluation method for a probe card according to claim 1 or 2, wherein the first moving step and the second moving step are performed. When the shape of the electrode pad in plan view is rectangular,
The probe card according to claim 3, wherein the plurality of directions are one direction parallel to the upper and lower sides of the rectangle and another direction parallel to the left and right sides of the rectangle. Quality evaluation method. When the shape of the electrode pad in plan view is circular,
4. The probe card quality evaluation method according to claim 3, wherein the plurality of directions are two directions orthogonal to each other. In the first moving step and the second moving step,
The probe card is moved in a state where the tip portions of the plurality of probe pins are in contact with the electrode pad at regular intervals, and the tip portions are separated from the electrode pad at other timings. The method for evaluating the quality of a probe card according to any one of claims 1 to 5. An apparatus for evaluating the quality of a probe card having a plurality of probe pins respectively corresponding to a plurality of electrode pads of a circuit element subjected to probe inspection,
Contact means for bringing each of the plurality of probe pins into contact with a corresponding one of the plurality of electrode pads;
The probe card is moved in the horizontal direction with respect to the electrode pad forming surface of the circuit element until at least one of the plurality of probe pins is separated from the corresponding electrode pad. Transportation means;
Second moving means for moving the probe card in a direction opposite to the first moving step until at least one of the plurality of probe pins is separated from the corresponding electrode pad; ,
First timing information when at least one of the probe pins is separated from the corresponding electrode pad in the first movement step, and at least one of the probe pins is in the second movement step. Information acquisition means for acquiring second timing information when leaving the corresponding electrode pad;
The probe card capable of bringing each of the plurality of probe pins into contact with a corresponding one of the plurality of electrode pads based on the first timing information and the second timing information. A probe card quality evaluation apparatus, comprising: a calculation means for calculating a position range. A stage for mounting circuit elements;
A probe card having a plurality of probe pins respectively corresponding to a plurality of electrode pads of the circuit element;
When inspecting the circuit element using a probe inspection apparatus comprising:
A probe inspection method, comprising: performing the probe card quality evaluation method according to any one of claims 1 to 6.

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