Patent Application
20250208169
The present disclosure relates to an inspection method and an inspection device.
Patent Document 1 discloses an inspection device for moving a wafer placed on an alignment stage to a position where the wafer is brought into contact with probes of a probe card. The inspection device performs processing including a step of acquiring card center coordinates of the probe card with a first acquisition part on the aligner side, and a step of acquiring reference coordinates in a target coordinate system of a reference target disposed at a pogo frame with the first acquisition part. Further, the inspection device performs processing including a step of acquiring common coordinates of the first acquisition part and a second acquisition part on the pogo frame side, a step of acquiring wafer center coordinates with the second acquisition part, and a step of moving an aligner by a command including contact coordinates determined based on the card center coordinates, the common coordinates, and the wafer center coordinates.
The technique of the present disclosure allows more accurate alignment between a substrate and probes of a probe card in an inspection device for inspects the substrate.
In accordance with one embodiment of the present disclosure, An inspection method for inspecting a substrate using an inspection device, comprising:
In accordance with the present disclosure, in an inspection device for inspecting a substrate, it is possible to more accurately align the substrate and the probes of the probe card.
In a semiconductor manufacturing process, a plurality of semiconductor devices having a predetermined circuit pattern are formed on a substrate such as a semiconductor wafer (hereinafter, referred to as “wafer”). The electrical characteristics of the formed semiconductor devices are inspected to classify them into non-defective products and defective products. For example, the semiconductor devices are inspected using an inspection apparatus before the substrate is divided into the semiconductor devices.
The inspection apparatus includes a probe card having a plurality of probes that are needle-shaped contact terminals. In the electrical characteristic inspection, first, the wafer and the probe card become close to each other, and the probes of the probe card are brought into contact with electrodes of the semiconductor devices formed on the substrate. In that state, an electrical signal is supplied from a test head disposed above the probe card to the semiconductor devices through the probes. Then, based on the electrical signal received by the test head from the semiconductor devices through the probes, the corresponding semiconductor devices are classified into defective products or non-defective products.
In order to appropriately perform the electrical characteristic inspection, the inspection device aligns the probes of the probe card with the wafer, specifically, aligns the probes with the electrodes on the wafer.
As shown in
However, the above-described alignment method needs to be improved in terms of alignment accuracy.
The technique of the present disclosure allows more accurate alignment between the substrate and the probes of the probe card in a substrate inspection device.
Hereinafter, the inspection method and the inspection device according to the present embodiment will be described with reference to the accompanying drawings. Like reference numerals will be used for like parts having substantially the same functions and configurations throughout the specification and the drawings, and redundant description thereof will be omitted.
The inspection device 1 shown in
Provided in the loading/unloading area 11 are a port 20 for receiving a cassette C containing a plurality of wafers W, a loader 21 accommodating a probe card to be described later, and a controller 22 for controlling individual components of the inspection device 1. The controller 22 is a computer including a central processing unit (CPU), a memory, or the like, and has a storage part (not shown) that stores various information. The storage part stores, e.g., a program including instructions for the inspection process. The program may be recorded in a computer-readable storage medium, and installed from the storage medium to the controller 22. The storage medium may be temporary or non-temporary. The program may be partially or entirely realized by dedicated hardware (circuit board). The storage part may be, e.g., a storage device such as a hard disk drive (HDD), a memory such as a random access memory (RAM) that stores temporarily required information related to the operation of the program, or a combination thereof.
A transfer device 30 that can freely move while holding a wafer W or the like is disposed in the transfer area 12. The transfer device 30 transfers the wafer W between the cassette C in the port 20 in the loading/unloading area 11 and the inspection area 13. Further, the transfer device 30 transfers a probe card that require maintenance, among probe cards fixed to a pogo frame to be described later in the inspection area 13, to the loader 21 in the loading/unloading area 11. Further, the transfer device 30 transfers a new probe card or a probe card subjected to maintenance from the loader 21 into the inspection area 13.
A plurality of testers 40 are disposed in the inspection area 13. Specifically, as shown in
The tester 40 transmits and receives an electrical signal for electrical characteristic inspection to and from the wafer W.
The aligner 50 is configured to hold a chuck top 70 to be described later and move it in the horizontal direction (X direction and Y direction in
The imaging part 60 images both the probes of the probe card and the wafer W placed on the chuck top 70.
The chuck top 70 is an example of a placing member on which the wafer W is placed. The chuck top 70 can hold the wafer W placed thereon by attraction, for example.
In the inspection device 1, while the transfer device 30 is transferring a wafer W toward one tester 40, the other tester 40 can inspect the electrical characteristics of electronic devices formed on another wafer W.
Next, the configuration of the inspection area 13 will be described in detail with reference to
As described above, the aligner 50 and the imaging part 60 are provided in each divided area 13a of the inspection area 13. Further, as shown in
The aligner 50 has, e.g., an X stage 51, a Y stage 52, and a Z stage 53.
The X stage 51 moves along a guide rail 51a extending in the horizontal direction (X direction in
The Y stage 52 moves on the X stage 51. Specifically, the Y stage 52 moves along a guide rail 52a extending in the horizontal direction (Y direction in
The Z stage 53 moves up and down by an extensible/contractible shaft 53a capable of extending and contracting in the vertical direction (Z direction in
The chuck top 70 is detachably attracted and held on the Z stage 53. The chuck top 70 is attracted and held on the Z stage 53 by vacuum attraction using an attraction holding mechanism (not shown).
The Z stage 53 is provided with a rotation mechanism (not shown) for rotating the Z stage 53 around the Z axis. The rotation mechanism has a driving part for driving the rotation, and the driving part has, e.g., a motor as a driving source for generating a driving force for the rotation.
The aligner 50 is controlled by the controller 22. Specifically, the driving parts of the X stage 51, the Y stage 52, and the Z stage 53 of the aligner 50 are controlled by the controller 22. Further, the position detection results obtained by the position detection mechanisms disposed at the X stage 51, the Y stage 52, and the Z stage 53 are outputted to the controller 22.
In the present embodiment, an aligner-side imaging unit 54 (third imaging unit of the present disclosure) is fixed to the aligner 50. Specifically, the aligner-side imaging unit 54 is fixed to the Z stage 53 of the aligner 50. Therefore, when the chuck top 70 held by the aligner 50 is moved, the aligner-side imaging unit 54 is also moved. In other words, the aligner 50 moves the aligner-side imaging unit 54 together with the chuck top 70.
The aligner-side imaging unit 54 recognizes a correction target 84 disposed at the pogo frame 80 to be described below. Specifically, the aligner-side imaging unit 54 images the correction target 84 in order to recognize the correction target 84.
The aligner-side imaging unit 54 has a camera including an optical system such as lenses and a light receiving device (specifically, photoelectric conversion device).
The aligner-side imaging unit 54 is controlled by the controller 22. The imaging result obtained by the aligner-side imaging unit 54 is outputted to the controller 22.
The aligner 50 is provided with a projection target 110 (see
As described above, the imaging part 60 images both the probes 91 of the probe card 90 and the wafer W placed on the chuck top 70. The imaging part 60 has a housing 60a. As shown in
The first imaging unit 61 recognizes the wafer W placed on the chuck top 70. Specifically, the first imaging unit 61 images the wafer W in order to recognize the wafer W placed on the chuck top 70.
The second imaging unit 62 recognizes the probes 91 of the probe card 90.
Specifically, the second imaging unit 62 images the probes 91 in order to recognize the probes 91 of the probe card 90.
Each of the first imaging unit 61 and the second imaging unit 62 has a camera including an optical system such as lenses and a light receiving device (specifically, photoelectric conversion device).
In the imaging part 60, the first imaging unit 61 and the second imaging unit 62 are provided on the same axis. Specifically, optical axes P1 and P2 of the camera of the first imaging unit 61 and the camera of the second imaging unit 62 are coaxial.
The imaging part 60 is controlled by the controller 22. The imaging result obtained by the imaging part 60 is outputted to the controller 22.
The imaging part 60 is configured to move in the horizontal direction (XY directions in
As shown in
The pogo frame 80 is disposed under the tester 40.
The pogo frame 80 is an example of a holder, and holds the probe card 90. The pogo frame 80 electrically connects the probe card 90 and the tester 40. The pogo frame 80 has pogo pins 81 for the electrical connection described above, and more specifically, has a pogo block 82 for holding a number of pogo pins 81.
The probe card 90 is fixed to the bottom surface of the pogo frame 80 while being aligned at a predetermined position.
The tester motherboard 41 is vacuum-attracted to the pogo frame 80 by an exhaust mechanism (not shown), and the probe card 90 is vacuum-attracted to the pogo frame 80. Due to the vacuum suction force for performing the vacuum attraction, the lower ends of the pogo pins 81 of the pogo frame 80 are brought into contact with corresponding electrodes on the upper surface of a card body 92 (to be described later) of the probe card 90, and the upper ends of the pogo pins 81 are pressed against corresponding electrodes on the bottom surface of the tester motherboard 41.
The probe card 90 has a disc-shaped card body 92 having a plurality of electrodes on the upper surface thereof. The plurality of probes 91 that are needle-shaped contact terminals extending downward are disposed on the bottom surface of the card body 92.
The above-described plurality of electrodes disposed on the upper surface of the card body 92 are electrically connected to the corresponding probes 91. During the inspection, the probes 91 are brought into contact with electrodes (not shown) of the semiconductor devices formed on the wafer W. Therefore, during the electrical characteristic inspection, the electrical signal for the inspection is transmitted between the tester motherboard 41 and the semiconductor devices on the wafer W via the pogo pins 81, the electrodes disposed on the upper surface of the card body 92, and the probes 91.
In the inspection device 1, a large number of probes 91 cover substantially the entire bottom surface of the card body 92 in order to collectively inspect electrical characteristics of the plurality of semiconductor devices formed on the wafer W.
A bellows 83 is attached to the bottom surface of the pogo frame 80. The bellows 83 is a cylindrical extensible/contractible member that is suspended to surround the probe card 90. As indicate by the dotted line in
The bellows 83 vacuum-attracts the chuck top 70, thereby forming a sealed space S surrounded by the pogo frame 80 including the probe card 90, the bellows 83, and the chuck top 70. The contact state between the wafer W and the probes 91 can be maintained by depressurizing the sealed space S with a depressurization mechanism (not shown).
The pogo frame 80 is provided with the correction target 84. The correction target 84 is used for determining a contact position. The contact position is the position of the chuck top 70 in the horizontal direction (X direction and Y direction in
The height of the correction target 84 is a height at which the wafer W placed on the chuck top 70 is close to but is not in contact with the probes 91 of the probe card 90 when the chuck top 70 is lifted together with the aligner-side imaging unit 54 so that the focus of the aligner-side imaging unit 54 is aligned with the correction target 84.
The horizontal position of the correction target 84 is the following position, for example. In other words, it is the position where the entire wafer W placed on the chuck top 70 overlaps the probes 91 in plan view when the chuck top 70 is moved together with the aligner-side imaging unit 54 such that the horizontal position of the aligner-side imaging unit 54 is located directly below the target. The position directly below the target position in the aligner-side imaging unit 54 is the position where the optical axis of the aligner-side imaging unit 54 and the correction target 84 (specifically, its center) coincide with each other.
As described above, the housing 60a of the imaging part 60 is configured to move in the horizontal direction and the vertical direction by the imaging moving mechanism 100 of
The imaging moving mechanism 100 has a pair of guide rails 101 and a pair of moving rails 102.
The guide rails 101 are disposed to extend along the horizontal direction (X direction
The pair of moving rails 102 are provided to extend in a horizontal direction, which is perpendicular to the guide rails 101 (Y direction in
Further, the pair of moving rails 102 support the housing 60a of the imaging part 60 to be movable along the extension direction of the moving rails 102 (Y direction in
The imaging moving mechanism 100 is controlled by the controller 22. Specifically, the driving part for the moving rails 102 and the housing 60a is controlled by the controller 22. Further, the position detection result obtained by the position detection mechanism disposed at the moving rails 102 and the housing 60a is outputted to the controller 22.
Next, an example of an inspection process including a contact position determining process using the inspection device 1 will be described with reference to
First, as shown in
Specifically, the transfer device 30 and the like are controlled by the controller 22, and the wafer W is taken out of the cassette C in the port 20 of the loading/unloading area 11. The wafer W is transferred into the upper divided area 13a, for example, and is placed on the chuck top 70 attracted and held by the aligner 50 corresponding to the desired tester 40.
Next, as shown in
Specifically, the aligner 50 is controlled by the controller 22, and the chuck top 70 on which the wafer W is placed is moved to a predetermined temporary contact position. If the chuck top 70 is set as the temporary contact position, all the probes 91 of the probe card 90 overlap the wafer W placed on the chuck top 70 in plan view, for example.
Further, the first imaging unit 61 and the second imaging unit 62 are moved to a position between the probe card 90 and the chuck top 70 disposed below the probe card 90.
Specifically, the imaging moving mechanism 100 is controlled by the controller 22, and the housing 60a of the imaging part 60 is moved to the above-described position.
The order of steps S2 and S3 may vary, and steps S2 and S3 may be performed simultaneously.
Next, the first imaging unit 61 images the wafer W placed on the chuck top 70, and the second imaging unit 62 images the probes 91 of the probe card 90 through the gap between the probe card 90 and the chuck top 70. In other words, the controller 22 acquires the representative position of the wafer W using the first imaging unit 61 located between the probe card 90 and the chuck top 70, and acquires the representative position of the probes 91 using the second imaging unit 62 located between the probe card 90 and the chuck top 70.
Specifically, the representative position of the wafer W is acquired based on the imaging result of the first imaging unit 61 and the detection result of the position detection mechanism of the imaging moving mechanism 100.
The representative position of the wafer W is, e.g., the center of gravity position of the electrodes disposed at multiple predetermined locations on the wafer W. The position (specifically, position coordinates) of each electrode can be obtained based on the output from the position detection mechanism of the imaging moving mechanism 100 that is obtained when the center of the electrode is located at the center of the image obtained by the first imaging unit 61, for example.
The representative position of the probes 91 is obtained based on the imaging result of the second imaging unit 62 and the detection result of the position detection mechanism of the imaging moving mechanism 100.
The representative position of the probes 91 is, e.g., the center of gravity position of the probes 91 at multiple predetermined positions on the probe card 90. The position (specifically, position coordinates) of each probes 91 can be obtained based on the output from the position detection mechanism of the imaging moving mechanism 100 when the tip end of the probe 91 is located at the center of the image obtained by the second imaging unit 62.
Then, the chuck top 70 is moved such that the horizontal position thereof becomes the reference position. In other words, the chuck top 70 is moved to the horizontal reference position. The reference position is a position where the horizontal position of the aligner-side imaging unit 54 becomes a predetermined position with respect to the correction target 84, and the predetermined position is a position directly below the target, for example.
In step S5, first, the chuck top 70 is moved to a contact position calculated based on the representative position of the wafer W placed on the chuck top 70 and the representative position of the probes 91, for example. In other words, the wafer W placed on the chuck top 70 and the probes 91 of the probe card 90 are aligned.
Specifically, the controller 22 corrects the temporary contact position based on the imaging results obtained by the first imaging unit 61 and the second imaging unit 62, and the corrected temporary contact position is determined as the contact position. Then, the controller 22 controls the aligner 50 to move the chuck top 70 to the determined contact position.
The correction of the temporary contact position is performed based on the representative position of the wafer W and the representative position of the probes 91 acquired in step S4, for example. More specifically, the temporary contact position is corrected to offset the positional deviation of the representative position of the wafer W from the representative position of the probes 91.
Then, based on the imaging results of the first imaging unit 61 and the second imaging unit 62, the chuck top 70 is moved, and the horizontal position thereof is set as the reference position.
Specifically, based on the imaging result of the second imaging unit 62, the controller 22 controls the imaging moving mechanism 100. First, as shown in
Then, based on the imaging result of the first imaging unit 61, the controller 22 controls the aligner 50, and the chuck top 70 is moved such that the aligner-side imaging unit 54 and the first imaging unit 61 become coaxial.
More specifically, above the aligner-side imaging unit 54, the projection target 110 is moved or projected to a position where it is focused with the aligner-side imaging unit 54 (i.e., a position where the optical axis P3 of the camera of the aligner-side imaging unit 54 coincides with the center of the projection target 110) under the control of the controller 22. Then, based on the imaging result of the projection target 110 by the first imaging unit 61, the controller 22 controls the aligner 50, and the chuck top 70, the aligner-side imaging unit 54, and the projection target 110 are moved such that the optical axis P1 of the camera of the first imaging unit 61 coincides with the projection target 110. This movement is performed such that the center of the projection target 110 coincides with the center of the image obtained by the first imaging unit 61, for example.
Accordingly, the horizontal position of the chuck top 70 becomes the reference position, and the horizontal position of the aligner-side imaging unit 54 becomes the position directly below the target.
Then, the controller 22 calculates the movement amount of the chuck top 70 from the contact position to the reference position. The movement amount is the horizontal movement amount, and is calculated, based on the output from the position detection mechanism of the aligner 50, for example.
After step S5, the first imaging unit 61 and the second imaging unit 62 are retracted from the area between the probe card 90 and the chuck top 70. Specifically, the imaging moving mechanism 100 is controlled by the controller 22, and portions that may interfere with the chuck top 70 of the imaging moving mechanism 100 and the housing 60a of the imaging part 60 to which the first imaging unit 61 and the second imaging unit 62 are fixed are retracted to the area between adjacent chuck tops 70 in the same divided area 13a.
Step S6 may be performed before step S5c, or steps S6 and S5c may be performed simultaneously.
Then, the chuck top 70 is lifted from the reference position, and the aligner-side imaging unit 54 images the correction target 84. The reference position is calibrated based on the image of the correction target 84 that is obtained by the aligner-side imaging unit 54.
Specifically, first, the controller 22 controls the aligner 50, and the chuck top 70 is lifted from the reference position to the focal height as shown in
If the lifting direction of the chuck top 70 and the aligner-side imaging unit 54 is appropriate and perpendicular to the correction target 84, the horizontal position of the aligner-side imaging unit 54 is not changed before and after the chuck top 70 is lifted to the focal height, and is located directly below the target. However, due to distortion of the housing 10 where the aligner 50 is installed, the lifting direction of the chuck top 70 and the aligner-side imaging unit 54 may be tilted without being perpendicular to the correction target 84. In this case, during the lifting of the chuck top 70 and the aligner-side imaging unit 54, the horizontal position of the aligner-side imaging unit 54 is gradually shifted from the position directly below the target. This indicates that as the chuck top 70 and the aligner-side imaging unit 54 are lifted, the horizontal reference position of the chuck top 70 is shifted with respect to the probe card 90 fixed to the pogo frame 80 provided with the correction target 84 is provided.
Therefore, in the present embodiment, the reference position of the chuck top 70 at the focal height is calibrated as follows.
In other words, based on the imaging result of the correction target 84 by the aligner-side imaging unit 54, the aligner 50 is controlled by the controller 22, and the chuck top 70 is moved such that the horizontal position of the aligner-side imaging unit 54 becomes directly below the target. This movement is performed such that the center of the correction target 84 is located at the center of the image obtained by the aligner-side imaging unit 54. Then, the controller 22 calculates the horizontal position of the chuck top 70 after the movement based on the output from the position detection mechanism of the aligner 50, and obtains it as the reference position after the calibration of the chuck top 70 at the focal height.
Accordingly, the reference position of the chuck top 70 before it is lifted to the focal height and the calibrated reference position of the chuck top 70 at the focal height are substantially the same with respect to the probe card 90 fixed to the pogo frame 80. In other words, the reference position is calibrated based on the horizontal misalignment of the reference position of the chuck top 70 during the lifting to the focal height, thereby eliminating the misalignment.
Then, the controller 22 corrects the contact position calculated from the imaging results obtained by the first imaging unit 61 and the second imaging unit 62 in step S4 based on the imaging result obtained by the aligner-side imaging unit 54 in step S5. Specifically, the controller 22 corrects the contact position determined in step S5 based on the calibrated reference position, for example.
More specifically, the controller 22 calculates the corrected contact position based on the following equations from the calibrated reference position of the chuck top 70 at the focal height acquired in step S7 and the amount of movement of the chuck top 70 from the contact position to the reference position calculated in step S5c.
In steps S7 and S8, the calibration of the reference position of the chuck top 70 and the correction of the contact position based on the calibrated reference position may also be performed in the direction around the Z axis.
Then, the controller 22 controls the aligner 50, and the chuck top 70 is moved to the corrected contact position and then lifted. The lifting continues until the wafer W and the probes 91 are brought into contact with each other.
In this case, the reference height of the chuck top 70, which determines the height to which the chuck top 70 is lifted, is determined as follows, for example.
In other words, for example, when the representative position of the wafer W is obtained in step S4, the height of the wafer W placed on the chuck top 70 (specifically, the height of the electrodes) and the height of the probes 91 are also obtained, and the controller 22 determines the reference height of the chuck top 70 from these heights.
The height of the wafer W placed on the chuck top 70 is obtained based on the imaging result of the first imaging unit 61 and the detection result of the vertical position of the imaging moving mechanism 100 by the position detection mechanism.
The height of the probes 91 is obtained based on the imaging result of the second imaging unit 62 and the detection result of the vertical position of the imaging moving mechanism 100 by the position detection mechanism.
Then, under the control of the controller 22, the chuck top 70 is attracted to the pogo frame 80.
Specifically, in a state where the wafer W and the probes 91 are in contact with each other, a depressurization mechanism (not shown) or the like is controlled and the Z stage 53 of the aligner 50 is lowered. Accordingly, the chuck top 70 is separated from the aligner 50 and attracted to the pogo frame 80.
After the chuck top 70 and the aligner 50 are separated, the electrical characteristic inspection of the electronic devices formed on the wafer W is performed.
The electrical signal for the electrical characteristic inspection is inputted from the tester 40 to the electronic devices via the pogo pins 81, the probes 91, and the like.
Then, the inspected wafer W is unloaded.
Specifically, the chuck top 70 that was attached to the pogo frame 80 is transferred to and held by the aligner 50. The inspected wafer W on the chuck top 70 held by the aligner 50 is unloaded from the inspection area 13 and returned to the cassette C in the port 20 of the loading/unloading area 11 by the transfer device 30.
During the inspection in one tester 40, the aligner 50 transfers the wafer W to be inspected to another tester 40 or collects the inspected wafer W from another tester 40.
In the embodiment described with reference to
In the present embodiment, when the chuck top 70 is lifted from the reference position, first, the correction target 84 is imaged by the aligner-side imaging unit 54, and the horizontal reference position of the chuck top 70 is calibrated based on the imaging result. Accordingly, the uncalibrated reference position at the height before the chuck top 70 is lifted and the calibrated reference position at the height after the chuck top 70 is lifted (specifically, the focal height) are substantially the same with respect to the probe card 90 fixed to the pogo frame 80. Therefore, the contact position before correction based on the uncalibrated reference position at the height before the lifting and the contact position after correction based on the calibrated reference position at the height after the lifting are substantially the same with respect to the probe card 90 fixed to the pogo frame 80. Since the horizontal misalignment of the chuck top 70 during the lifting of the chuck top 70 is considered, the alignment between the wafer W and the probes 91 of the probe card 90 can be performed more accurately in the present embodiment.
In Example 2 of the inspection process, steps S1 to S4 are performed in the same manner as that in Example 1 of the inspection process.
In Example 2 of the inspection process, subsequent to step S4, the chuck top 70 is moved to the horizontal reference position (step S21), similarly to Example 1 of inspection process. However, in this example, unlike Example 1 of inspection process, the reference position is a contact position calculated from the imaging results obtained by the first imaging unit 61 and the second imaging unit 62 in step S4, specifically, a contact position calculated based on the representative position of the wafer W and the representative position of the probes 91 acquired in step S4.
Next, similarly to step S7 of Example 1 of the inspection process, the chuck top 70 is lifted from the reference position, and the correction target 84 is imaged by the aligner-side imaging unit 54.
However, in step S22, unlike the above-described step S7, for example, first, before the chuck top 70 is lifted from the reference position, the controller 22 controls the imaging moving mechanism 100, and the housing 60a of the imaging part 60 is moved such that the first imaging unit 61 and the aligner-side imaging unit 54 become coaxial. In other words, the alignment of the second imaging unit 62 that is moved together with the housing 60a is performed.
Specifically, under the control of the controller 22, the projection target 110 is advanced to a position above the aligner-side imaging unit 54 where it is focused with the aligner-side imaging unit 54. Then, based on the imaging result of the projection target 110 by the first imaging unit 61, the controller 22 controls the imaging moving mechanism 100 to move the housing 60a of the imaging part 60 such that the optical axis P1 of the camera of the first imaging unit 61 coincides with the projection target 110. This movement is performed such that the center of the projection target 110 is located at the center of the image obtained by the first imaging unit 61, for example.
Then, the correction target 84 is imaged by the aligned second imaging unit 62.
Specifically, in a state where the housing 60a of the imaging part 60 is moved to a position where the optical axis P1 of the camera of the first imaging unit 61 coincides with the projection target 110, the correction target 84 provided at the pogo frame 80 is imaged by the second imaging unit 62. Accordingly, an image Im1 including a mark M1 of the correction target 84 as shown in
Next, similarly to step S6 of Example 1 of the inspection process, the first imaging unit 61 and the second imaging unit 62 are retracted from the area between the probe card 90 and the chuck top 70.
Then, the chuck top 70 is lifted from the reference position, and the correction target 84 is imaged by the aligner-side imaging unit 54.
Specifically, first, the controller 22 controls the aligner 50, and the chuck top 70 is lifted from the reference position to the focal height. Then, the correction target 84 is imaged by the aligner-side imaging unit 54. Accordingly, an image Im2 including the mark M1 of the correction target 84 as shown in
Then, the controller 22 corrects the contact position calculated from the imaging results obtained by the first imaging unit 61 and the second imaging unit 62 in step S4 based on the imaging results of the correction target 84 by the second imaging unit 62 and the aligner-side imaging unit 54.
Specifically, the controller 22 corrects the contact position based on the imaging result of the correction target 84 by the second imaging unit 62 in step S22b and the imaging result of the correction target 84 by the aligner-side imaging unit 54 in step S22d.
More specifically, based on the imaging result of the correction target 84 by the second imaging unit 62 in step S22b and the imaging result of the correction target 84 by the aligner-side imaging unit 54 in step S22d, the controller 22 corrects the contact position such that both imaging results coincide with each other. In other words, based on the image Im1 of
Then, similarly to step S9 in Example 1 of the inspection process, the controller 22 controls the aligner 50, and the chuck top 70 is moved to the corrected contact position and then lifted. The lifting is continued until the wafer W and the probes 91 are brought into contact with each other.
In a state where the chuck top 70 is located at the contact position after correction, the aligner-side imaging unit 54 may image the correction target 84 again, as in step S22d. Then, the degree of coincidence between the image of the correction target 84 by the second imaging unit 62 in step S22b and the image of the correction target 84 by the aligner-side imaging unit 54 may be determined. Specifically, it may be determined that the degree of misalignment of the position of the correction target 84 in the image obtained by the aligner-side imaging unit 54 with respect to the position of the correction target 84 in the image obtained by the second imaging unit 62 falls within a predetermined range. If the degree of coincidence is not sufficient, i.e., if the degree of misalignment does not fall within the predetermined range, the contact position may be corrected again until it falls within the predetermined range.
After the contact position is corrected, steps S10 to S12 are performed, similarly to Example 1 of the inspection process.
In Example 2 of the inspection process, similarly to Example 1 of the inspection process, the wafer W and the probes 91 of the probe card 90 can be aligned more accurately. In Example 2 of the inspection process, the horizontal misalignment of the chuck top 70 during the lifting of the chuck top 70 is considered, so that the wafer W and the probes 91 of the probe card 90 can be aligned more accurately.
An angle discrimination target 110A illustrated in
In the case of using the angle discrimination target 110A, when the first imaging unit 61 and the aligner-side imaging unit 54 become coaxial in step S22a, the housing 60a of the imaging part 60 is moved as follows. In other words, based on the imaging result of the angle discrimination target 110A by the first imaging unit 61, the controller 22 controls the imaging moving mechanism 100, and the housing 60a of the imaging part 60 is moved such that the optical axis P1 of the camera of the first imaging unit 61 coincides with the angle discrimination target 110A. This movement is performed such that the center of the line segment L that connects the two marks M2 and M2 is located at the center of an image Im4 obtained by the first imaging unit 61, as shown in
In the case of using the angle discrimination target 110A, the first imaging unit 61 images the angle discrimination target 110A in a state where the first imaging unit 61 and the aligner-side imaging unit 54 are coaxial in step S22a.
Further, the controller 22 acquires the relative angle of the aligner-side imaging unit 54 based on the imaging result of the angle discrimination target 110A by the first imaging unit 61.
Specifically, the controller 22 calculates an angle θ of the line segment L from the image Im4 obtained by the first imaging unit 61 in a state where the first imaging unit 61 and the aligner-side imaging unit 54 are coaxial, and obtains it as the relative angle of the aligner-side imaging unit 54.
In the case of correcting the contact position in step S23, the controller 22 performs the correction based on the imaging results of the correction target 84 by the second imaging unit 62 and the aligner-side imaging unit 54 and the relative angle of the aligner-side imaging unit 54.
Specifically, the controller 22 corrects the imaging result of the correction target 84 by the second imaging unit 62 based on the above relative angle. Further, the controller 22 corrects the contact position such that the imaging result of the correction target 84 by the corrected second imaging unit 62 and the imaging result of the correction target 84 by the aligner-side imaging unit 54 coincide with each other.
In other words, the controller 22 corrects the above-described image Im1 in
The controller 22 may correct the imaging result of the correction target 84 by the aligner-side imaging unit 54 based on the relative angle, and correct the contact position such that the imaging result of the correction target 84 by the corrected aligner-side imaging unit 54 coincided with the imaging result of the correction target 84 by the second imaging unit 62.
In accordance with the modification of Example 2 of the inspection process using the inspection device 1, the contact position is corrected in consideration of the relative angle of the aligner-side imaging unit 54, so that the alignment between the wafer W and the probes 91 of the probe card 90 can be performed more accurately.
In the inspection process using the inspection device 1, similarly to the modification of Example 2 of the inspection process, the relative angle of the aligner-side imaging unit 54 may be obtained using the angle discrimination target 110A, and the contact position may be corrected using the relative angle.
In the above examples, the first imaging unit 61 and the second imaging unit 62 are provided in the same housing, but they may be provided in separate housings. However, it is preferable that they are provided in the same housing because it is unnecessary to perform a process of associating the coordinate system based on the image obtained by the first imaging unit 61 with the coordinate system based on the image obtained by the second imaging unit 62.
In the above example, when the first imaging unit 61 and the second imaging unit 62 are provided in the same housing, the optical axis of the first imaging unit 61 and the optical axis of the second imaging unit 62 are aligned, but they may be misaligned. In that case, information on the positional relationship between the optical axis of the first imaging unit 61 and the optical axis of the second imaging unit 62 is also used to calibrate the reference position.
However, it is difficult to accurately recognize the positional relationship between the optical axis of the first imaging unit 61 and the optical axis of the second imaging unit 62 when they are misaligned, and the positional relationship changes due to distortion of the housing 10 caused by a temperature. Thus, when the first imaging unit 61 and the second imaging unit 62 are provided on the same axis, it is possible to more reliably obtain the appropriate contact position, i.e., to more reliably perform appropriate alignment.
In the above example, only one aligner-side imaging unit 54 and one correction target 84 are provided, but multiple aligner-side imaging units 54 (two in the illustrated example) and multiple correction targets 84 (two in the illustrated example) may be provided as shown in
In this case, in the process in which the chuck top 70 is lifted from the reference position and the correction targets 84 is imaged by the aligner-side imaging units 54, each aligner-side imaging unit 54 images the corresponding correction target 84. Further, in the process in which the contact position is corrected based on the imaging results of the correction targets 84 by the aligner-side imaging units 54, the contact position is corrected based on the imaging results obtained by the multiple aligner-side imaging units 54.
Specifically, in the above-described Example 1 of the inspection process, when the chuck top 70 is moved to the reference position in step S5, each of the multiple aligner-side imaging units 54 is used. Then, when the reference position is calibrated in step S7, the corresponding correction target 84 is imaged by each of the aligner-side imaging units 54, and the above-described calibration is performed based on the imaging results.
Further, in Example 2 of the inspection process, in steps S22a and S22b, in each of the aligner-side imaging units 54, the alignment of the second imaging unit 62 and the imaging of the corresponding correction target 84 by the aligned second imaging unit 62 are performed. Further, in step S22d, the corresponding correction target 84 is imaged by each of the multiple aligner-side imaging units 54. Then, in step S23, in each of the aligner-side imaging units 54, the contact position is corrected such that the imaging result of the corresponding correction target 84 by the second imaging unit 62 in step S22b coincides with the imaging result of the corresponding correction target 84 in step S22d.
In the case of using the relative angle of the aligner-side imaging unit 54, the relative angle is acquired for each of the aligner-side imaging units 54. Further, in step S23, for each of the aligner-side imaging units 54, one of the imaging result in step S22b and the imaging result in step S22d is corrected based on the relative angle. Then, for each of the aligner-side imaging units 54, the contact position is corrected such that the corrected result coincides with the uncorrected result.
By providing the plurality of aligner-side imaging units 54 and the plurality of correction targets 84 as described above, the alignment between the wafer W and the probes 91 of the probe card 90 can be performed more accurately.
It should be noted that the above-described embodiments are illustrative in all respects and are not restrictive. The above-described embodiments may be omitted, replaced, or changed in various forms without departing from the scope of the appended claims and the gist thereof. For example, the components of the above-described embodiments can be randomly combined. The effects of the components for arbitrary combination can be obtained from the corresponding arbitrary combination, other effects apparent to those skilled in the art can also be obtained.
The effects described in the present specification are merely explanatory or exemplary, and are not restrictive. In other words, in the technique related to the present disclosure, other effects apparent to those skilled in the art can be obtained from the description of the present specification in addition to the above-described effects or instead of the above-described effects.
the following configuration examples are also included in the technical scope of the present disclosure.
(1) An inspection method for inspecting a substrate using an inspection device, comprising:
(2) The inspection method of (1), wherein the reference position of the placing member is a position where a horizontal position of the third imaging unit becomes a predetermined position with respect to the target, and in said (D), the reference position is calibrated based on the imaging result of the target by the third imaging unit, and in said (E), the contact position is corrected based on the calibrated reference position.
(3) The inspection method (2), wherein the first imaging unit and the second imaging unit are fixed to a common housing, and
(4) The inspection method of (2) or (3), wherein the predetermined position is a position directly below the target where an optical axis of the third imaging unit coincides with the target.
(5) The inspection method of (4), wherein said (C) includes:
(6) The inspection method of (1), wherein the reference position of the placing member is the contact position before correction.
(7) The inspection method of (6), wherein the first imaging unit and the second imaging unit are fixed to a common housing, and
(8) The inspection method of (7), wherein in said (E), the contact position is corrected such that the imaging result of the target by the second imaging unit and the imaging result of the target by the third imaging unit coincide with each other.
(9) The inspection method of (7) or (8), wherein said moving the housing in said (D) includes moving the housing based on the imaging result of another target disposed between the first imaging unit and the third imaging unit by the first imaging unit,
(10) The inspection method of (9), wherein in said (E), any one of the imaging results of said another target by the first imaging unit and the third imaging unit is corrected based on the angle of the third imaging unit with respect to the housing in the top view, and the contact position is corrected such that the corrected result coincides with the uncorrected result.
(11) The inspection method of (9) or (10), wherein said another target has two marks spaced apart from each other.
(12) The inspection method of any one of (1) to (11), wherein the inspection device has a plurality of the third imaging units,
(13) An inspection device for inspecting a substrate, comprising:
(14) The inspection device of (13), wherein the reference position of the placing member is a position where a horizontal position of the third imaging unit is located at a predetermined position based on the target,
(15) The inspection device of (14), further comprising:
(16) The inspection device of (14) or (15), wherein the predetermined position is a position directly below the target where an optical axis of the third imaging unit coincides with the target.
(17) The inspection device of (16), wherein said (C) includes:
(18) The inspection device of (13), wherein the reference position of the placing member is the contact position before correction.
(19) The inspection device of (18), further comprising:
(20) The inspection device of (19), wherein in said (E), the contact position is corrected such that the imaging result of the target by the second imaging unit and the imaging result of the target by the third imaging unit coincide with each other.
(21) The inspection device of (19) or (20), wherein said moving the housing in said (D) includes moving the housing based on an imaging result of another target disposed between the first imaging unit and the third imaging unit by the first imaging unit,
(22) The inspection device of (21), wherein in said (E), any one of the imaging results of said another target by the first imaging unit and the third imaging unit is corrected based on the angle of the third imaging unit with respect to the housing in top view, and the contact position is corrected such that the corrected result coincides with the uncorrected result.
(23) The inspection device of (21) or (22), wherein said another target has two marks spaced apart from each other.
(24) The inspection device of any one of (13) to (23), wherein the inspection device has a plurality of the third imaging units,
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-056364 | Mar 2022 | JP | national |
| 2022-163809 | Oct 2022 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2023/010422 | 3/16/2023 | WO |
