JP5189759B2 - Inspection method and inspection apparatus - Google Patents

Description

The present invention relates to an inspection method and inspection equipment.

  In a semiconductor manufacturing process such as IC or LSI, a circuit pattern is formed on the surface of a wafer by processes such as exposure, development, and etching. In addition, after the circuit pattern is formed, an inspection is performed as to whether or not the circuit pattern is peeled off from the surface of the wafer and there are no defects such as scratches or adhesion of foreign matter. A transport device is used when transporting a substrate to each substrate processing apparatus that performs processing such as exposure, development, etching, and inspection.

  In the semiconductor industry, the diameter of a wafer has been increased in order to increase production efficiency, and the use of a wafer having a diameter of 300 mm is already in full swing. In addition, in order to increase the yield of semiconductor manufacturing processes that are highly integrated and multi-layered, inspection devices with high length measurement accuracy are also required. In Patent Document 1 described later, a probe device having a structure capable of preventing an accident at the time of accommodation due to warpage of an object to be inspected and reducing damage to the object to be inspected as a non-defective product with a simple structure. Is described. Here, a method of adsorbing the back surface of the wafer when it is transported to a processing machine or a wafer cassette is adopted.

In FIG. 14, in the conventional inspection apparatus, an edge grip type transfer apparatus configured to hold and handle the edge portion of the wafer is used.
In FIG. 14, a surface inspection apparatus 100 using an SEM or the like for inspecting the presence or absence of foreign matter or defects on the wafer surface is housed in an inspection chamber 10 of the inspection apparatus. In this inspection chamber 10, wafers can be taken in and out using sealed pods (for example, FOUP (Front Opening Unified Pod)) 11 and 12 that can accommodate a plurality of wafers. Done.

Taking one pod 11 as an example, first, when the pod 11 is set in the load port before the inspection and the shutter of the inspection chamber 10 is opened, the openable lid is opened. Then, the wafer is transferred from the slot of the pod 11 in which the wafer is stored to the pre-aligner cradle 15 for alignment by the transfer device 14 having the handling arm 13. In the pre-aligner cradle 15, the orientation of the wafer is adjusted (alignment) for surface inspection, and then the wafer is set again on the edge clip type measurement table 101 of the surface inspection apparatus 100 by the transport device 14. The controller 200 controls the processing operations of the surface inspection apparatus 100 and the conveyance apparatus 14, and the CRT 201 notifies the operator of the progress of inspection, the progress of conveyance, and the like. The wafer subjected to the surface inspection is returned from the measurement table 101 to the original slot of the pod 11 by the transfer device 14. After all wafers in the pod 11 have been inspected, the lid is closed and the shutter in the inspection chamber 10 is closed. The wafer in the other pod 12 is inspected after all the processing of the wafer in the pod 11 is completed.
Japanese Patent Laid-Open No. 06-236910

  By the way, in the transfer device 14 using the edge grip type handling arm 13, since there is no contact on the back surface of the wafer during transfer, the contamination can be effectively prevented. In addition, an edge grip method is adopted for the handling arm 13 constituting the transfer device 14 so that the front and back surfaces of the wafer are reversed and surface inspection (for convenience, inspection of the wafer back surface using the surface inspection device is also referred to as surface inspection). )) To analyze the correlation with the product yield.

  However, if the amount of warpage of the wafer is large, for example, the wafer being transferred falls from the handling arm 13 in the process from taking out from the pod 11 to carrying out the inspection in the inspection chamber 10 and storing it in the pod 11 again. There is a case. Further, when the wafer is set on the surface inspection apparatus 100, the wafer surface may be damaged due to contact or collision with the measurement table 101 due to the warpage. In particular, if a wafer is dropped or cracked in a process closer to the final process, all the costs of the wafer processing process up to that point will be lost, resulting in a significant loss in terms of cost and yield. Occur.

  In addition, when the amount of warpage is measured by adsorbing the back surface of the wafer, the state of the warpage is corrected, so even if the amount of warpage is measured before the surface inspection, Since the warping direction changes, depending on the structure of the measuring table 101, it is difficult to accurately predict whether or not the back surface of the wafer contacts the inner surface.

According to one aspect of the present invention, a flat test object is placed on a support that supports the lower surface of the edge of the test object, and is opposed to the test object that is placed on the support. The detector is disposed on the stage to emit a light beam substantially parallel to the surface of the stage, the direction of the light beam is changed, and the surface of the inspection object is irradiated to the inspection object. The amount of warpage of the object to be inspected placed on the support is measured by receiving reflected light reflected from the surface and changed in direction again, and the measured amount of warpage is a threshold value. comparison, if the amount of the warpage is less than the threshold value, the said edge is gripped to carry the, transported the edge support to the inspection of the inspection of the object to be inspected and An inspection method is provided.

  According to such an inspection method, the amount of warpage of an uncorrected test object with the edge supported is measured, and when the amount of warpage is less than a threshold value, the edge is gripped. Therefore, it is possible to avoid, for example, dropping the inspection object immediately before the inspection or damaging the inspection object due to interference with the inspection apparatus side.

Further, according to one aspect of the present invention, a flat plate-like object to be inspected is placed, and a support means for supporting the lower surface of the edge of the object to be inspected is provided opposite to the object to be inspected. And a stage disposed on the stage, emitting a light beam substantially parallel to the surface of the stage, changing the direction of the light beam and irradiating the surface of the object to be inspected. A warp detecting means comprising: a detector for measuring the amount of warping of the object to be inspected with the lower surface of the edge supported by the supporting means by receiving reflected light that has been reflected from and changed in direction again. A conveying means for grasping the edge and conveying the object to be inspected, and an amount of the warp measured by the warp detecting means and supporting the edge of the object to be inspected conveyed by the conveying means. Inspection means for performing Inspection apparatus is provided.

According to such an inspection apparatus, the supporting lifting means to support the edge of the object to be inspected, the warp detection unit measures the amount of warpage of the supported the test subject. Since the amount of warpage is measured when the inspection object is inspected, for example, it is possible to avoid dropping the inspection object immediately before the inspection or damaging the inspection object due to interference with the inspection apparatus side.

According to the disclosed technology, an inspection object that satisfies a certain amount of warpage before the inspection can be inspected. Therefore, in the inspection process employing the edge clip method, the inspection object immediately before the inspection It is possible to suppress damage to the object to be inspected due to dropping or interference with the inspection apparatus side. Therefore, for example, it is possible to reduce the cost of manufacturing the semiconductor device and improve the yield. Further, by knowing the amount of warpage of the object to be inspected measured during the manufacturing process, it is possible to obtain a correlation with the manufacturing yield of the semiconductor device.

Also, by measuring the warpage of the test subject during state like that supports the edges, so it is possible to suppress damage to the device under test due to interference with the dropping or inspection apparatus of the device under test during transportation Thus, for example, it is possible to reduce the cost of manufacturing the semiconductor device and improve the yield.

Hereinafter, it will be described with reference to the drawings forms of implementation.
Examples of the object to be inspected include a flat semiconductor wafer (wafer), an ALTIC substrate, a glass substrate, a disk substrate, and the like. Here, the wafer will be described as an example.

First, the first embodiment will be described.
FIG. 1 is a flowchart showing a wafer warpage evaluation method.
In step S1, a wafer warpage threshold is set (setting step). Here, as will be described later, a sample wafer having a film of a predetermined material formed on the wafer surface with a predetermined thickness is used, the sample wafer is placed on a predetermined support base, The difference value in the thickness direction at the location is measured, and a threshold value is set according to the difference value or an average value thereof, the magnitude of variation, and the like.

  In step S2, the amount of wafer warpage is measured (measurement process). Here, the wafers stored in the slots of a predetermined pod are transported by an edge grip type handling arm and placed on a predetermined support base in the same manner as in the case of the sample wafer, and at six locations near the outer periphery with respect to the center. The difference value (warpage amount) in the thickness direction is measured.

  Step S3 is a comparison process in which the measured value of the amount of warpage of the wafer is compared with a threshold value. Here, for example, each time a difference value is measured in the measurement process, each difference value is used as a wafer warp amount and compared with a threshold value. Or after calculating | requiring the average value of six difference values, the average value is made into a wafer curvature amount, and a comparison with a threshold value is performed. If the difference value at each location or the average value of the difference values at 6 locations, that is, the amount of warpage of the wafer is greater than or equal to the threshold value, the process proceeds to step S6 to output an error signal.

  In step S4, a wafer having a wafer warpage amount less than a threshold value is transferred from the support table to the surface inspection apparatus by the handling arm, and a predetermined inspection is performed there. Thereafter, the wafer is stored in the original slot of the pod by the handling arm in step S5.

  When the wafer warp amount is equal to or greater than the threshold value, the process proceeds to step S6 as described above and an error signal is output. Then, the wafer is not inspected, and is returned from the support base to the original slot of the pod by the handling arm in step S5.

Here, a threshold value setting method using a sample wafer will be described first.
2 and 3 are plan views showing positions for measuring the amount of warpage of the sample wafer.
The sample wafer 1 is supported in a horizontal state by a support table including four support arms 2a to 2d, such as the pre-aligner receiving table 15 described in FIG. The sample wafer 1 is transported by a predetermined handling arm from above in the drawing, and a sensor provided in the vicinity of the support arm 2d is used as shown in FIGS. While rotating 1, six measurement points a to f in the vicinity of the outer periphery are sequentially sensed to align the notch 1 n. Then, at the time of this notch alignment, for example, sensing by infrared irradiation or the like from the side surface direction of the sample wafer 1 with respect to any one of the measurement point at the center of the sample wafer 1 and the measurement points a to f near the outer periphery thereof. And the difference between them, that is, the amount of warpage of the sample wafer 1 is calculated from the sensing results of the two measurement points. Alternatively, sensing is performed by irradiating infrared rays in a direction perpendicular to the plane of the sample wafer 1 with respect to any one of the measurement points a to f near the outer periphery of the measurement point at the center of the sample wafer 1. You may make it obtain | require the curvature amount.

4A and 4B are diagrams showing an example of the measurement of the amount of warpage of a sample wafer. FIG. 4A is a schematic diagram showing a state during measurement of the amount of warpage, and FIG. 4B is an example of the measurement result of the amount of warpage.
Here, as the sample wafer 1, a wafer having three types of concave shapes as follows was used. The sample wafer W1 is formed by forming a suitable insulating film on the bare wafer so as to warp it in a concave shape so that the total thickness thereof becomes 350 μm. The sample wafer W2 is formed by forming the above insulating film on the same bare wafer so that the total thickness thereof becomes 400 μm. The sample wafer W3 is formed by forming the above insulating film on the same bare wafer so that the total thickness thereof becomes 450 μm. That is, the insulating films as described above are formed thick in the order of the sample wafers W1, W2, and W3.

  If these sample wafers W1-W3 are mounted on a support stand, the sample wafers W1-W3 will bend in the direction which enlarges actual curvature by the dead weight. FIG. 4B shows the value obtained by subtracting this offset value from the actual difference value obtained by sensing two measurement points near the wafer center and its outer periphery, assuming that the offset value is 100 μm. Amount. As shown in FIG. 4B, it can be seen that the thicker the predetermined insulating film, the larger the difference value, that is, the amount of warpage of the wafer.

5A and 5B are diagrams showing an example of the measurement of the amount of warpage of another sample wafer, in which FIG. 5A is a schematic diagram showing a state at the time of measuring the amount of warpage, and FIG. 5B is an example of the result of measurement of the amount of warpage.
Here, as the sample wafer 1, a wafer having three types of convex shapes as follows was used. The sample wafer W4 is formed by forming an appropriate insulating film on the bare wafer so as to warp it in a convex shape so that the total thickness thereof becomes 350 μm. The sample wafer W5 is formed by forming the above insulating film on the same bare wafer so that the total thickness thereof becomes 400 μm. Further, the sample wafer W6 is formed by forming the above-described insulating film on the same bare wafer so that the total thickness thereof becomes 450 μm.

  When these sample wafers W4 to W6 are placed on the support base, the warpage amount of the sample wafers W4 to W6 becomes smaller than the actual warpage due to its own weight. FIG. 5B shows the amount of wafer warpage obtained by setting this offset value to 100 μm. As shown in FIG. 5B, it can be seen that the thicker the insulating film, the larger the difference value, that is, the amount of warpage of the wafer.

  4B and 5B show the central measurement point, the average value of the difference values at each measurement point, and the magnitude of variation (Max-Min) for each of the sample wafers W1 to W6. Yes. The threshold value used for determining whether or not transport from the support table is possible can be set based on the average value of such difference values and the magnitude of variation.

  The actual threshold value is obtained by measuring the amount of warpage as shown in FIGS. 4 and 5 using a product wafer (for convenience sake, a sample wafer) or a sample wafer having a configuration close to the product wafer. It is set based on the average value to be obtained, the size of variation, or the clearance that can be set in the transfer device or the surface inspection device. The set threshold value data is stored in the conveyance control unit 202 of FIG.

  Here, as the warp detection means, infrared irradiation from the side surface direction or the plane vertical direction of the wafer is used, but other detection means using other light beam irradiation can also be used.

Next, a procedure for measuring the amount of wafer warpage during inspection will be described.
FIG. 6 is a flowchart showing an example of a procedure for measuring the amount of warpage of a wafer.
In step S11, the wafer is transferred to a pre-aligner cradle that is a support means. In this pre-aligner cradle, wafer notch alignment (alignment) is performed. Therefore, before the alignment, in the next step S12, it is detected whether or not the wafer has been transferred to the cradle.

  However, the wafer immediately after being placed on the pre-aligner cradle by the transfer handling arm may be vibrating. Therefore, in step S13, the waiting time until the start of measurement is set to 3 seconds so as to ensure the stability of the measured value.

Thereafter, in step S14, the wafer warpage is detected, that is, the amount of wafer warpage is measured, and the alignment in step S15 is performed.
After the wafer warpage amount is measured by the warp detection process in step S14, the wafer warpage amount is compared with a predetermined threshold value as shown in FIG. That is, when the amount of warpage of the wafer is less than the threshold value, the wafer is transferred from the pre-aligner cradle to the surface inspection apparatus. Returned to the slot. As a result, it is possible to avoid wafer damage or the like when performing inspection with the surface inspection apparatus.

Next, the configuration (interlock mechanism) of the inspection apparatus that determines the quality of the wafer (whether it can be transferred to the surface inspection apparatus) based on the threshold value of the amount of warpage of the wafer will be described.
FIG. 7 is a block diagram showing an example of an inspection apparatus.

The inspection apparatus includes a surface inspection apparatus 100 that inspects the presence or absence of foreign matter on the wafer surface, a controller 200, and a wafer warp detection unit 300.
The wafer warp detection unit 300 includes two sensor heads 31a and 31b, amplifier units 32a and 32b, and an analog controller 33, and measures the amounts of warpage of various wafers according to the procedure shown in FIGS. That is, the center of the wafer and the vicinity of the outer periphery thereof are sensed by the two sensor heads 31a and 31b, and a difference value between the two measurement points is obtained.

  The difference value measured by the wafer warp detection unit 300 is transmitted to the transfer control unit 202 of the controller 200 that determines whether or not to transfer the wafer to the surface inspection apparatus 100. The transfer control unit 202 stores threshold value data set in advance for a wafer to be inspected.

  The controller 200 calculates the wafer warpage amount using the received difference value, and determines whether the wafer warpage amount is in a normal range based on the threshold value stored in the transfer control unit 202. Thus, an error signal is output from the controller 200 to the surface inspection apparatus 100 for a wafer with a large warp, and is not conveyed to the surface inspection apparatus 100. As a result, it is possible to avoid wafer damage when the surface inspection apparatus 100 performs inspection.

  As described above, in the first embodiment, the transfer means for gripping and transferring the edge of the wafer, the support means for supporting the transferred wafer by the edge, and the wafer supported by the edge. A warp detection means for measuring the amount of warpage, a process judgment means for comparing the measured warpage amount with a threshold value and judging the subsequent processing (determining whether or not it can be conveyed to the surface inspection apparatus), based on the judgment The amount of warpage of the wafer is taken into account by using a control means that controls the transfer of the wafer, a reversing means that inverts the front and back surfaces of the wafer, and an inspection means that inspects the front or back surface of the transferred wafer. However, the inspection can be performed while avoiding the fall or damage. In addition to these means, the inspection apparatus further includes an input means for inputting a threshold value, a storage means for storing the input threshold value, and a display for displaying a threshold value, an error signal, and the like. Means are provided.

Next, the entire processing procedure of the inspection will be described.
FIG. 8 is a flowchart showing a flow of an inspection procedure performed as a part of the semiconductor manufacturing process.

First, the shutter of the load port connected to the inspection room and the lid of the pod containing the wafer are opened, and the handling arm receives the wafer from the pod (step S21).
When the inspection surface of the wafer in the inspection process is the back surface, in order to invert the wafer, the wafer is placed on the cradle of the inversion unit (steps S22 and S23), the front and back surfaces are inverted (step S24), and handling is performed. The arm receives the inverted wafer (step S25). Thereafter, the wafer in the inverted state received by the handling arm is placed on a pre-aligner cradle that is a support means (step S26).

  On the other hand, when the inspection surface of the wafer in the inspection process is the front surface, the reversing is not performed, and the handling arm places the wafer as it is on the pre-aligner cradle (steps S22 and S26).

  The inverted or non-inverted wafer placed on the pre-aligner cradle is subjected to the above-described warpage detection and evaluation prior to alignment (step S27). Then, the wafers are sorted according to the evaluation result here (step S28), and alignment is executed for those whose warpage amount is less than the threshold value (step S29). The wafer after alignment is transferred to the measuring table of the surface inspection apparatus by the handling arm (steps S30 and S31).

  The measurement table is placed on a side chuck stage or the like so as not to damage the surface of the patterned wafer. After the inspection by the surface inspection apparatus is executed (step S32), the wafer is transferred to the designated load port and stored in the original slot of the pod (step S33).

When all the inspected wafers are accommodated in the pod, the lid is closed and the shutter of the load port is closed.
If the amount of wafer warpage detected in step S28 is greater than or equal to the threshold value, the wafer is transferred from the pre-aligner cradle to the pod and stored in the original slot (step S33).

  As described above, in the first embodiment, when performing an inspection, a predetermined threshold value of the amount of warpage of the wafer is set in advance, and the amount of warpage of the wafer is detected before the actual wafer inspection. Is compared with a threshold value, and based on the comparison result, it is determined whether or not to transfer the wafer to the surface inspection apparatus for inspection. As a result, when inspecting with a surface inspection device, it is possible to avoid contact or collision with the device side due to dropping, warping, etc. of the wafer until it is transferred to the device, and it is possible to prevent damage to the wafer surface Therefore, it is possible to reduce the cost of manufacturing the semiconductor device and improve the yield.

  In the above description of the first embodiment, when the wafer back surface is inspected, the case where the wafer is reversed while being transferred from the pod to the pre-aligner cradle has been described as an example. The wafer may be reversed while being transferred to the inspection apparatus. In such a case, the amount of warpage is detected before the wafer is reversed, and it is determined whether or not the wafer can be transferred. Therefore, the wafer can be reliably reversed, and further, an apparatus that causes the wafer to fall or warp. It is possible to avoid contact and collision with the side. This also makes it possible to efficiently collect inspection information on the backside of the wafer. The inspection information on the wafer back surface can be used, for example, for analyzing the correlation between the state of the wafer back surface and the yield.

  In the above-described wafer inspection procedure, the amount of warpage is detected immediately after being placed on the pre-aligner cradle, but the amount of warpage can be detected before that. For example, before the wafer is taken out from the pod by the handling arm of the transfer device, the above-described warpage detection and evaluation may be performed in the state of being accommodated in each slot of the pod. When the warpage amount is less than a predetermined threshold value, the wafer is taken out by the handling arm and transferred to the pre-aligner cradle. As a result, the wafer can be reliably transferred while being prevented from being dropped or damaged from the handling arm while the wafer is placed on the pre-aligner cradle from the pod. Further, when the wafer needs to be reversed between the pod and the pre-aligner cradle, the wafer can be reliably reversed and the wafer back surface can be inspected.

Furthermore, as described above, the amount of warpage can be detected immediately after being placed on the pre-aligner cradle, and the amount of warpage can be detected after alignment.
It is also possible to detect the amount of warp in advance as described above before setting the pod containing the wafer in the load port. In that case, if the data of the slot number of the pod and the warpage amount of the wafer stored therein is transmitted to the controller of the handling arm using an appropriate communication means, the operation of the handling arm is performed based on the received data. Can be controlled.

  The wafer warpage evaluation results described above can be used not only in the inspection process but also in other processes, and also used for analyzing the correlation between the amount of warpage and yield in various processes. Is possible.

Next, a second embodiment will be described.
FIG. 9 is a plan view illustrating a configuration example of the inspection apparatus according to the second embodiment.
The inspection apparatus includes a plurality of load ports 520, a conveyance unit 530, a warp detection unit 540, an inspection unit 550, and a data processing unit 560.

  On each load port 520, a pod 510 containing a plurality of wafers 500 to be inspected is placed. In addition to using all the load ports 520 as pods 510 in which the wafers 500 to be inspected are housed, a part of the load ports 520 can be used exclusively for collecting the wafers 500 determined to be defective.

  The data processing unit 560 includes a controller 561, an input device 562 including a keyboard, a touch panel, or a mouse, a display device 563 including a CRT or a flat panel display, an output device 564 such as a printer, and an external device for controlling external media. The storage device 565 is configured.

  The controller 561 includes an arithmetic processing device 561a, a storage device 561b such as an HDD, and a transport control unit 561c. The controller 561 controls the entire inspection device based on a command from the input device 562, displays the setting condition, the inspection result, the operation state of the inspection device, and the like on the display device 563, and further outputs the information to the output device 564. Is output. A warpage amount threshold value of a wafer 500 to be described later is input via the input device 562, stored in the storage device 561b or the transfer control unit 561c, and displayed based on a command from the input device 562 or the arithmetic processing unit 561a. Displayed on device 563.

  The transfer of the wafer 500 is started by executing a transfer program. The data processing unit 560 drives a servo motor via a pulse control board and a drive circuit (not shown), and operates and controls the handling arm 532 provided in the transport device 531. The handling arm 532 carries out the wafer 500 from the slot of the pod 510 in accordance with an instruction from the data processing unit 560 and transports it from the load port 520 to the warp detection unit 540.

Here, FIG. 10 is a figure which shows the structural example of a handling arm front-end | tip part, Comprising: (A) is a top view, (B) is CC sectional view taken on the line of (A).
As shown in FIG. 10, a substantially U-shaped fork 533 having inclined portions 534 a to 534 d that hold the edge of the wafer 500 is disposed at the tip of the handling arm 532. A holding side wall surface 535 is formed at the upper end of the inclined portions 534c and 534d positioned in front of the fork 533, and the wafer 500 is configured to be able to be held. The wafer 500 is placed at a substantially central position with respect to the radial positions of the inclined portions 534a to 534d, is urged toward the inclined portions 534c and 534d by the urging portion 536, and is held by the fork 533. The wafer 500 can be unloaded from the pod 510 without bringing the back surface into contact with the fork 533 by the transfer means having such a gripping mechanism.

  The warpage detection unit 540 has a function of measuring a warpage amount of the wafer 500 and a position adjustment (pre-alignment) function of the wafer 500. In an inspection apparatus that does not require pre-alignment of the wafer 500, the inspection apparatus can be configured only with a warpage amount detection function, or can function only with a warpage amount detection function.

Here, FIG. 11 is a diagram illustrating a configuration example of the warp detection unit, in which (A) is a plan view and (B) is a side view.
The wafer 500 is transported to the support base 541 shown in FIG. 11 while being held by the tip of the handling arm 532, and the biasing portion 536 is attached to a position where the centers of the wafer 500 and the support base 541 coincide. The force is released and placed on the support base 541. The wafer 500 on the support base 541 is lifted by a support mechanism 542 configured to be movable and rotatable in the X, Y, Z, and θ directions, and placed on a plurality of support arms 543a to 543c that also serve as a placement function. And supported. The support base 541 and the support arms 543a to 543c support the wafer 500 with a small area at the edge thereof, and suppress contamination on the back surface of the wafer 500. In addition, the support arms 543a to 543c can suppress a warp shape change caused by an external force such as adsorption, and can measure the original warpage of the wafer 500 due to film formation or thermal history. By these support means, contamination on the back surface of the wafer 500 can be suppressed, and an accident occurring in the inspection unit 550 can be predicted in advance.

  The support arms 543a to 543c of the support mechanism 542 are configured by three, and the edge portions of the wafer 500 are supported by the three support portions 544a to 544c. Such a support means absorbs the influence of the height variations of the support arms 543a to 543c caused by processing tolerances, attachment adjustments, and the like, and suppresses rotation during warpage measurement and swing and vibration of the wafer 500 during conveyance. To do. Such an effect of suppressing the swinging and vibration of the support means improves the measurement accuracy of the warp and reduces the waiting time related to the vibration, improves the reliability and throughput of the inspection apparatus, and improves the adjustment and maintenance. Further, the support by the three support portions 544a to 544c stabilizes the holding of the wafer 500, and enables the size of the support portions 544a to 544c to be configured in a compact manner. Note that two or more support arms 543a to 543c are applicable. Two support parts 544a to 544c are widened in order to stabilize the holding state, and if there are four or more, there is a high possibility that the above-mentioned swinging or vibration occurs. Preferably, a supporting unit that supports three edges of the wafer 500 with the three supporting portions 544a to 544c of the supporting mechanism 542 having three supporting arms 543a to 543c is desirable.

  As shown in FIG. 9, a length measuring stage 545 is provided above the support table 541 so as to face the wafer 500, and one or more for measuring the distance from the wafer 500 on the length measuring stage 545. The sensor head, here, a detector composed of two sensor heads 546 a and 546 b is disposed at a position for measuring the substantially central portion and the outer peripheral portion of the wafer 500. The sensor heads 546a and 546b are configured as a laser displacement meter that emits a light beam, receives a reflected light of the light beam, and measures a distance between the sensor heads, and reflecting mirrors 547a and 547b positioned in front of the sensor heads. Then, the direction of the light beam emitted from the lateral direction emitted substantially parallel to the surface of the length measuring stage 545 is changed to irradiate the surface of the wafer 500, and further the direction of the reflected light from the surface is changed. To receive light. The distance from the wafer 500 is detected by a change in the position of a light beam spot such as a laser beam on an optical position detection element provided in the sensor heads 546a and 546b with respect to a reference distance. Adjustment of the sensor heads 546a and 546b to the reference distance is performed by position adjusters 548a and 548b disposed on the reflecting mirrors 547a and 547b. With such a warp detecting means including a reference distance position adjusting means and a light beam direction changing means, a warp measuring mechanism is configured in the lateral direction of the length measuring device stage 545, suppressing an increase in the vertical direction, and measuring warpage Reduce the size of the mechanism.

  The distance to the wafer 500 is measured for each point on the outer peripheral portion at one or more edge points and a substantially central point that are specified in advance by rotating the support mechanism 542. Based on the difference between the distances detected from the substantially central portion and the outer peripheral portion, the warpage amount of the wafer 500 is calculated by the transfer control unit 561c or the arithmetic processing unit 561a, and the storage device (not shown) in the transfer control unit 561c, or the storage Store in device 561b. The data on the amount of warp, the radius of curvature and polarity calculated based on the data (the warp direction and shape such as concave and convex, compressive stress, tensile stress, etc.) and the stress value are input device 562, controller 561 or display device. Based on an instruction on a setting screen or the like on 563, it is displayed on display device 563, and is output to output device 564 as necessary.

  Further, a threshold value of a warpage amount, which will be described later, and a correction value (offset value) of the warpage amount that is deformed by the weight of the wafer 500 are input from the setting screen displayed on the display device 563 via the input device 562. It is stored in the storage device 561b. Based on the warpage amount, the threshold value, and the set value of the offset value, the data processing unit 560 determines the subsequent processing of the wafer 500 and executes processing such as inspection continuation, conveyance stop, inspection object recovery, and error display. To do.

  Here, the sensor heads 546a and 546b are measured from the upper surface of the wafer 500 using a laser displacement meter. However, it is sufficient that the distance from the wafer 500 can be measured, and an optical sensor such as a laser focus type or a triangulation type may be used. In addition, a capacitive proximity sensor and an ultrasonic sensor can be applied, and measurement can be performed from the lower surface of the wafer 500.

  The sensor 549 includes a light emitting unit such as a laser beam and a light receiving unit such as a CCD line sensor, and rotates the support mechanism 542 on which the wafer 500 is placed to detect the position and intensity of light reaching the light receiving unit from the light emitting unit. The positions of the outer periphery of the wafer 500 and the V notch (or orientation flat) are detected.

  During the rotation of the support mechanism 542, the warpage measurement can be made continuous. In addition to improving the throughput of the inspection apparatus by speeding up the transfer process, the amount of warpage of the wafer 500 averaged in the circumferential direction can be measured.

  The data processing unit 560 drives the pulse motor through a pulse control circuit and a drive circuit (not shown) based on the detection result of the sensor 549, moves and rotates the support mechanism 542, and performs pre-alignment of the wafer 500.

  A cradle for a reversing unit (not shown) is disposed above the length measuring stage 545. When the front surface inspection of the back surface of the wafer 500 is performed, the front and back surfaces of the wafer 500 are reversed by the reversing unit. A linear guide arranged in parallel is provided on the front surface of the casing of the warp detection unit 540, and a base of a cradle is installed on the linear guide. The wafer 500 placed on the cradle rises along the linear guide and reverses the front and back surfaces of the wafer 500 via a clamp mechanism (not shown) disposed on the upper part. The wafer 500 is placed on the cradle, descends along the linear guide, and moves to the original position with the front and back surfaces reversed. In addition to the front surface of the wafer 500, the back surface of the wafer 500 can be inspected by means of reversing the front and back surfaces of the wafer 500.

The wafer 500 that has been pre-aligned is held by the handling arm 532 and transferred to the inspection unit 550 in the same manner as described above.
Here, FIG. 12 is a cross-sectional view showing a configuration example of the measurement table of the inspection unit.

  The surface inspection apparatus 551 of the inspection unit 550 includes an edge grip type measurement table 552. As shown in FIG. 12, a mounting unit 553 provided with an inclined surface on the inner surface side of the measurement table 552 is provided on the measurement table 552. Projected on the outer periphery. The wafer 500 is released from the bias and set on the mounting portion 553, and after the handling arm 532 is pulled out, the shutter 571 is closed. The wafer 500 is urged to the mounting portion 553 by a holding mechanism including a claw 554 of a clamp mechanism disposed on the outer peripheral portion of the measurement table 552, and the edge thereof is held by the measurement table 552. The measurement table 552 that holds the wafer 500 is moved to an inspection position, where an inspection using a light beam or the like is performed. In addition to the light beam, an electron beam, an X-ray, a magnetic field, an ultrasonic wave, a probe, or the like can be used for the inspection.

Moreover, FIG. 13 is sectional drawing which shows an example of the wafer mounting state of a measurement stand.
When the wafer 500 is warped, when the wafer 500 is placed on the measurement table 552, the wafer 500 and the inner surface of the measurement table 552 come into contact with each other as shown in FIG. . In addition, the foreign matter 602 generated at the time of contact may adhere to a wafer to be processed following the wafer 500, which may increase the contamination and affect the inspection result. By measuring the amount of warpage and the direction of warpage of the wafer 500 that are not corrected by the warp detection unit 540, the data processing unit 560 determines subsequent processing based on the data, thereby preventing the above-described accident in advance. Can do.

  As described above, the warp detecting means for measuring the warp amount of the wafer 500, the input means for inputting the set value of the warp amount threshold value, the storage means for storing the input warp amount threshold value, and the threshold value are displayed. Display processing means for comparing the warpage amount measured by the warpage detection means with the threshold value of the warpage amount input by the input means and stored in the storage means, and determining the processing of the wafer 500. By providing a control means for controlling the processing of the wafer 500 based on the judgment, a reversing means for reversing the front and back surfaces of the wafer 500 by the reversing unit, and an inspecting means for inspecting the presence or absence of defects on the wafer 500, the inspection apparatus Accidents that occur can be prevented. Further, in addition to the above, the inspection apparatus is provided with an alarm transmission means for issuing an alarm based on the determination of the processing determination means, and a display means for displaying an error based on the alarm transmission means. Can be improved.

Next, the inspection flow in the second embodiment will be described.
The inspection of the wafer 500 according to the second embodiment can be performed in the same manner as the flow described in the first embodiment. Hereinafter, the inspection method according to the second embodiment will be described with reference to FIGS. 1 to 8 and FIGS. 9 to 12.

  In performing the warpage evaluation of the wafer 500, as shown in FIG. 1, first, a threshold value of the warpage amount of the wafer 500 is set (step S1). Here, a sample wafer having a predetermined material film formed on the surface is used, and the sample wafer is placed on a support base 541 in the thickness direction at six locations near the outer periphery with respect to the center. The difference value is measured, and a threshold value is set according to the difference value or the average value thereof, the magnitude of variation, and the like.

  Next, the warpage amount of the wafer 500 is measured (step S2). Here, the wafer 500 accommodated in the slot of the predetermined pod 510 is transported by the edge grip type handling arm 532 and placed on the support table 541 as in the case of the sample wafer. Difference values (warpage amounts) in the thickness direction at six locations are measured.

  Next, the measured value of the warpage amount of the wafer 500 is compared with a threshold value (step S3). Here, for example, each time a difference value is measured in step S <b> 2, each difference value is used as a warp amount of the wafer 500 and compared with a threshold value. Alternatively, after obtaining the average value of the difference values at the six locations, the average value is used as a warp amount of the wafer 500 and compared with a threshold value. If the difference value at each location or the average value of the difference values at 6 locations, that is, the amount of warpage of the wafer 500 is greater than or equal to the threshold value, an error signal is output (step S6).

  The wafer 500 having a warp amount less than the threshold value is transferred from the support base 541 to the surface inspection device 551 by the handling arm 532, and a predetermined inspection is performed there (step S4). Thereafter, the wafer 500 is stored in the original slot of the pod 510 by the handling arm 532 (step S5).

  For the wafer 500 in which the warpage amount of the wafer 500 is equal to or larger than the threshold value in step S3 and the error signal is output in step S6, the process proceeds to step S5 without performing the inspection in step S4, and the handling arm 532 is processed. As a result, the original slot of the pod 510 is returned from the support base 541.

  The threshold value setting in step S1 is a setting means for storing in the storage device 561b the threshold value input via the input device 562 from the setting screen provided on the display device 563 before or during execution of the transfer program. It is done at. In the operation mode in which a plurality of wafers 500 housed in the pod 510 are continuously or automatically inspected, steps S2 to S6 are routinely performed on each wafer 500.

  The threshold value of the warpage amount can be set by a method as shown in FIGS. That is, for the sample wafer that is transported by the handling arm 532 and supported by the support base 541 including the support arms 543a to 543c of the warp detection unit 540, the sensor 549 is used to align the notches as shown in FIGS. Is done. At the time of the notch alignment, sensing using the sensor heads 546a and 546b is performed on the measurement point at the center of the sample wafer and the measurement points in the vicinity of the outer periphery thereof, and the amount of warpage of the sample wafer is calculated. Then, for example, sample wafers W1 to W6 as shown in FIGS. 4 and 5 are used, the average value of the difference value between the measurement point in the center and the measurement point in the vicinity of the outer periphery, the magnitude of the variation, the transfer device 531 and the surface inspection. Based on the clearance and the like that can be set in the device 551, a threshold value used for determining whether or not the carrier 541 can be conveyed is set. The set threshold value data is stored in the conveyance control unit 561c of the controller 561 or the storage device 561b.

Next, a procedure for measuring the amount of warpage of the wafer 500 will be described with reference to FIGS. 6 and 9 to 11.
First, the wafer 500 is transferred to the support base 541 of the warp detection unit 540 that is a support means (step S11). The warp detection unit 540 performs alignment of the wafer 500, but before the alignment, it is detected whether or not the wafer 500 has been transferred to the support base 541 (step S12). Since the wafer 500 immediately after being placed on the support base 541 by the handling arm 532 may be vibrating, the waiting time until the start of measurement is set to 3 seconds (step S13), and the stability of the measurement value is set. Secure. Thereafter, warpage of the wafer 500 is detected (step S14), and alignment is performed (step S15).

  After the measurement of the warpage amount of the wafer 500, as shown in FIG. 1, the warpage amount of the wafer 500 is compared with a predetermined threshold value. When the warpage amount of the wafer 500 is less than the threshold value, the wafer 500 is transferred from the warpage detection unit 540 to the surface inspection apparatus 551, and when the warpage amount of the wafer 500 is equal to or greater than the threshold value, The wafer 500 is returned to the original slot of the pod 510. As a result, it is possible to avoid damage to the wafer 500 when the surface inspection apparatus 551 performs inspection.

  Determination of the quality of the wafer 500 (whether it can be transferred to the surface inspection apparatus 551) based on the warpage amount and the threshold value of the wafer 500 is realized by an interlock mechanism according to the example of FIG. That is, in the case of the second embodiment, the warp detection unit 540 senses the center of the wafer 500 and the vicinity of the outer periphery using the two sensor heads 546a and 546b, and obtains a difference value between the two measurement points. The difference value is transmitted to the conveyance control unit 561c of the controller 561 and the like. The controller 561 calculates the warpage amount of the wafer 500 using the received difference value, and determines whether the warpage amount is in a normal range based on the threshold value stored in the transfer control unit 561c or the like. For the wafer 500 with a large warp, an error signal is output from the controller 561 to the surface inspection apparatus 551 and is not transferred to the surface inspection apparatus 551. This avoids damage to the wafer 500 when the surface inspection apparatus 551 performs the inspection.

Next, the processing procedure of the entire inspection according to the second embodiment will be described with reference to FIGS. 8 and 9 to 12.
First, the shutter of the load port 520 connected to the transfer unit 530 and the lid of the pod 510 accommodating the wafer 500 are opened, and the handling arm 532 receives the wafer 500 from the pod 510 (step S21).

  When the inspection surface of the wafer 500 in the inspection process is the back surface, in order to reverse the wafer 500, the wafer 500 is placed on the cradle of the reversing unit (steps S22 and S23), and the front and back surfaces are reversed (step S24). ), The handling arm 532 receives the inverted wafer 500 (step S25). Thereafter, the inverted wafer 500 received by the handling arm 532 is placed on the support base 541 of the warp detection unit 540 as support means (step S26).

  On the other hand, when the inspection surface of the wafer 500 in the inspection process is the front surface, the reversal is not performed, and the handling arm 532 places the wafer 500 on the support base 541 as it is (steps S22 and S26).

  The inverted or non-inverted wafer 500 placed on the support table 541 is supported by the support means of the support arms 543a to 543c prior to alignment, and the above-described warpage detection and evaluation are performed (step S27). . Then, according to the evaluation result here, the wafer 500 is sorted (step S28), and alignment is executed for those whose warpage amount is less than the threshold value (step S29). The wafer 500 that has been aligned is transferred to the measuring table 552 of the surface inspection apparatus 551 by the handling arm 532 (steps S30 and S31).

  The measurement table 552 is placed on a side chuck stage or the like so as not to damage the surface of the patterned wafer 500. After the inspection by the surface inspection apparatus 551 is executed (step S32), the wafer 500 is transferred to the designated load port 520 and stored in the original slot of the pod 510 (step S33).

When all the inspected wafers 500 are stored in the pod 510, the lid is closed and the shutter 572 of the load port 520 is closed.
If the warpage amount of the wafer 500 detected in step S28 is equal to or greater than the threshold value, the wafer 500 is transferred from the support base 541 of the warpage detection unit 540 to the pod 510 and stored in the original slot.

  As described above, in the second embodiment, when inspection is performed, a predetermined threshold is set in advance for the warpage amount of the wafer 500, and the warpage of the wafer 500 is performed before the actual inspection of the wafer 500. The amount is detected and compared with a threshold value, and based on the comparison result, it is determined whether or not to transfer the wafer 500 to the surface inspection apparatus 551 for inspection. Thereby, when inspecting by the surface inspection apparatus 551, the wafer 500 can be prevented from falling, contacting or colliding with the apparatus side due to warping until it is transferred to the apparatus, and the surface of the wafer 500 can be damaged. Therefore, it is possible to reduce the cost of manufacturing the semiconductor device and improve the yield.

  In the above description of the second embodiment, when the back surface of the wafer 500 is inspected, the case where the wafer 500 is reversed while being transferred from the pod 510 to the warp detection unit 540 has been described as an example. The wafer 500 may be reversed while being transferred from the warp detection unit 540 to the surface inspection apparatus 551. In such a case, the amount of warpage is detected before the wafer 500 is reversed, and it is determined whether or not the wafer 500 can be transferred. Therefore, the wafer 500 can be reliably reversed. It is possible to avoid contact or collision with the apparatus side due to warping. This also makes it possible to efficiently collect inspection information on the back surface of the wafer 500. The inspection information on the back surface of the wafer 500 can be used, for example, for analysis of the correlation between the state of the back surface of the wafer 500 and the yield.

  Further, in the above-described inspection procedure of the wafer 500, the warpage amount is detected immediately after being placed on the support base 541. However, the warpage amount can be detected before that. For example, before the wafer 500 is taken out from the pod 510 by the handling arm 532 of the transfer device 531, the above-described warpage detection and evaluation may be performed in a state of being accommodated in each slot of the pod 510. When the warpage amount is less than a predetermined threshold value, the handling arm 532 takes out the wafer 500 and transfers it to the support base 541. Accordingly, the wafer 500 can be reliably transferred while being prevented from dropping or breaking from the handling arm 532 while the wafer 500 is placed on the support base 541. In addition, when the wafer 500 needs to be reversed between the pod 510 and the warp detection unit 540, the wafer 500 can be reliably reversed and the back surface of the wafer 500 can be inspected.

Further, as described above, the amount of warpage can be detected immediately after being placed on the support arms 543a to 543c, and the amount of warpage can be detected after alignment.
Further, before setting the pod 510 in which the wafer 500 is stored in the load port 520, the warp amount as described above is detected in advance using this inspection apparatus or a separately provided warp measuring apparatus for the wafer 500. It is also possible. In that case, the slot number of the pod 510 and the warpage data of the wafer 500 accommodated in the pod 510 are stored in the controller 561 of the inspection apparatus, or an appropriate communication means of the warp measurement apparatus as described above is used. The operation of the handling arm 532 can be controlled based on the stored or received data transmitted to the controller 561. Further, from the setting screen provided on the display device 563, the warpage amount data and the unchecked slot number are input via the input device 562 and stored in the controller 561, and the handling arm is based on the data. The operation of 532 can also be controlled.

  The above-described warpage evaluation result of the wafer 500 can be used not only in the inspection process but also in other processes, and is used for analyzing the correlation between the warpage amount and the yield in various processes. It is possible.

(Supplementary note 1) In the inspection method for inspecting the object to be inspected,
Before inspection, grip the edge to transport the object to be inspected,
Measure the amount of warpage of the object to be inspected while supporting the edge of the object to be inspected,
Comparing the measured amount of warpage with a preset threshold;
When the amount of warpage is less than the threshold value, the edge of the object to be inspected is gripped and conveyed to perform the inspection.
Inspection method characterized by that.

(Appendix 2) When measuring the amount of warpage of the object to be inspected while supporting the edge of the object to be inspected,
Reverse the front and back surfaces of the object to be inspected, measure the amount of warpage in a state of supporting the edge of the inverted object to be inspected,
When the amount of warpage is less than the threshold value, when gripping and transporting the edge of the object to be inspected,
2. The inspection method according to appendix 1, wherein the inspected object to be inspected is gripped and conveyed, and the inspected object is inspected.

(Supplementary Note 3) When the amount of warpage is less than the threshold value, when carrying out the inspection by gripping and transporting the edge of the object to be inspected,
The inspection method according to appendix 1, wherein the inspection object is conveyed by reversing the front and back surfaces of the object to be inspected, which is conveyed while holding the edge.

(Appendix 4) When measuring the amount of warpage of the object to be inspected while supporting the edge of the object to be inspected,
The inspection method according to any one of appendices 1 to 3, wherein the warpage amount is measured and the inspection object is aligned.

(Supplementary Note 5) When carrying the object to be inspected by gripping the edge before the inspection,
The inspection method according to any one of appendices 1 to 4, wherein the edge portion of the inspection object is gripped and conveyed from a pod having a slot in which the inspection object is accommodated.

(Additional remark 6) When carrying the said to-be-inspected object by grasping the edge before the inspection,
Grasping and transporting the edge of the object to be inspected from a pod having a slot in which the object to be inspected is stored,
When the measured amount of warpage is less than the threshold value, the edge of the object to be inspected is gripped and conveyed to perform the inspection,
The inspection method according to any one of appendices 1 to 5, wherein when the measured amount of warpage is equal to or greater than the threshold value, the object to be inspected is transported and stored in the slot of the pod. .

(Appendix 7) When measuring the amount of warpage of the object to be inspected while supporting the edge of the object to be inspected,
The inspection according to any one of appendices 1 to 6, wherein a difference value in a thickness direction at a location near the outer periphery with respect to the center of the inspection object is measured, and the amount of warpage is obtained using the difference value. Method.

(Supplementary Note 8) In an inspection apparatus for inspecting an object to be inspected,
Transport means for gripping the edge and transporting the object to be inspected;
A support means for placing the object to be inspected conveyed by the conveying means and supporting the edge of the object to be inspected;
Warpage detection means for measuring the amount of warpage of the object to be inspected supported by the support means;
Inspection means for inspecting the object to be inspected;
An inspection apparatus comprising:

(Supplementary note 9) In an inspection apparatus for inspecting an object to be inspected,
Transport means for gripping the edge and transporting the object to be inspected;
A support means for placing the object to be inspected conveyed by the conveying means and supporting the edge of the object to be inspected;
Warpage detection means for measuring the amount of warpage of the object to be inspected supported by the support means;
Inspection means for inspecting the object to be inspected;
Processing determination means for comparing the amount of warpage measured by the warpage detection means with a preset threshold value to determine processing of the object to be inspected;
Control means for controlling the conveyance of the object to be inspected based on the judgment by the processing judgment means;
Inspection apparatus, comprising a.

(Supplementary Note 10) An input device for inputting the threshold value;
A storage device for storing the input threshold value;
A display device for displaying the stored threshold value;
The inspection apparatus according to appendix 9, characterized by comprising:

(Supplementary note 11) The inspection apparatus according to supplementary note 9 or 10, further comprising reversing means for inverting the front and back surfaces of the object to be inspected.
(Additional remark 12) The said support means supports the said to-be-inspected object by which the front and back were reversed by the said inversion means,
The inspection apparatus according to appendix 11, wherein the warp detection means measures the amount of warpage of the object to be inspected that is inverted by the inversion means and supported by the support means.

(Supplementary Note 13) The warp detection means is provided to detect the amount of warpage of the object to be inspected supported by the support means, and to provide the detector provided to face the object to be inspected. And the stage,
The detector emits a light beam substantially parallel to the surface of the stage, the direction of the light beam is changed, irradiated to the surface of the object to be inspected, reflected from the surface of the object to be inspected, and the direction again The inspection apparatus according to any one of appendices 9 to 12, wherein the amount of warping is measured by receiving the changed reflected light.

  (Additional remark 14) The said detector measures the distance of the said stage and the said to-be-inspected object using two or more places using the said light beam, and measures the said curvature amount using the difference. 13. The inspection apparatus according to 13.

  (Additional remark 15) The said support means supports the said to-be-inspected object in the support part of three places, The inspection apparatus in any one of Additional remarks 9-14 characterized by the above-mentioned.

It is a flowchart which shows the curvature evaluation method of a wafer. It is a top view (the 1) which shows the position of the curvature amount measurement of a sample wafer. It is a top view (the 2) which shows the position of the curvature amount measurement of a sample wafer. It is a figure which shows an example of the curvature amount measurement of a sample wafer, Comprising: (A) is a schematic diagram which shows the state at the time of curvature amount measurement, (B) is an example of a curvature amount measurement result. It is a figure which shows an example of the curvature amount measurement of another sample wafer, Comprising: (A) is a schematic diagram which shows the state at the time of curvature amount measurement, (B) is an example of a curvature amount measurement result. It is a flowchart which shows the procedure of the curvature amount measurement of a wafer. It is a block diagram which shows an example of an inspection apparatus. It is a flowchart which shows the flow of the test | inspection procedure implemented as a part of semiconductor manufacturing process. It is a top view which shows the structural example of the test | inspection apparatus of 2nd Embodiment. It is a figure which shows the structural example of a handling arm front-end | tip part, Comprising: (A) is a top view, (B) is CC sectional view taken on the line of (A). It is a figure which shows the structural example of a curvature detection part, Comprising: (A) is a top view, (B) is a side view. It is sectional drawing which shows the structural example of the measurement stand of a test | inspection part. It is sectional drawing which shows an example of the wafer mounting state of a measurement stand. It is a block diagram which shows the structure of the conventional inspection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, W1-W6 Sample wafer 1n Notch 2a, 2b, 2c, 2d, 543a, 543b, 543c Support arm 10 Inspection room 11, 12 Pod 13,532 Handling arm 14,531 Transfer device 15 Pre-aligner cradle 31a, 31b, 546a , 546b Sensor head 32a, 32b Amplifier unit 33 Analog controller 100, 551 Surface inspection device 101, 552 Measuring table 200 Controller 202, 561c Transfer control unit 300 Wafer warpage detection unit 500 Wafer 510 Pod 520 Load port 530 Transfer unit 533 Fork 534a, 534b, 534c, 534d Inclined portion 535 Holding side wall surface 536 Energizing portion 540 Warpage detecting portion 541 Support base 542 Support mechanism 544a, 544b, 544c Support unit 545 Length measuring device stage 547a, 547b Reflector 548a, 548b Position adjuster 549 Sensor 550 Inspection unit 553 Mounting unit 554 Claw 560 Data processing unit 561 Controller 561a Arithmetic processing unit 561b Storage unit 562 Output unit 563 Output unit 564 Device 565 External storage device 571, 572 Shutter 601 Defect 602 Foreign matter

Claims (10)

A flat plate-like object to be inspected is placed on a support that supports the lower surface of the edge of the object to be inspected,
Using a detector disposed on a stage facing the object to be inspected placed on the support, a light beam is emitted substantially parallel to the surface of the stage, and the direction of the light beam is The warpage of the object to be inspected placed on the support is received by receiving reflected light that has been changed, irradiated to the surface of the object to be inspected, reflected from the surface of the object to be inspected, and changed in direction again. Measure the quantity,
Comparing the measured amount of warpage with a threshold,
When the amount of warpage is less than the threshold, the edge of the object to be inspected is gripped and conveyed, and the edge of the object to be inspected is supported and inspected.
Inspection method characterized by that. When placing the object to be inspected on the support,
The test object is placed on the support by inverting the front and back surfaces of the test object,
When measuring the amount of warpage of the object to be inspected placed on the support,
Measuring the amount of warpage of the object to be inspected inverted and placed on the support;
When the amount of warpage is less than the threshold, the edge of the object to be inspected is gripped and conveyed, and the edge of the object to be inspected is supported and the inspection is performed. Is
2. The inspection method according to claim 1, wherein the edge of the object to be inspected is gripped and conveyed, and the inspection is performed while supporting the edge of the object to be inverted. When the amount of warpage is less than the threshold, the edge of the object to be inspected is gripped and conveyed, and the edge of the object to be inspected is supported and the inspection is performed. Is
2. The inspection is performed by inverting the front and back surfaces of the object to be inspected conveyed while holding the edge, and supporting the edge of the inspected object to be inverted. Inspection method. When measuring the amount of warpage of the object to be inspected placed on the support,
The inspection method according to claim 1, wherein the measurement of the amount of warpage and the alignment of the object to be inspected placed on the support are performed. A flat plate-like object to be inspected, and support means for supporting the lower surface of the edge of the object to be inspected,
A stage provided opposite to the object to be inspected, a stage disposed on the stage, emitting a light beam substantially parallel to the surface of the stage, and changing the direction of the light beam, the object to be inspected Detection that measures the amount of warping of the object to be inspected with the lower surface of the edge supported by the support means by receiving reflected light that is irradiated on the surface and reflected from the surface of the object to be inspected and changed in direction again. A warp detecting means comprising:
Transport means for gripping the edge and transporting the object to be inspected;
Inspection means for supporting the edge of the object to be inspected and measuring the amount of warpage by the warp detection means and transported by the transport means; and
An inspection apparatus comprising: Processing judgment means for judging the processing of the object to be inspected by comparing the amount of warpage measured by the warpage detection means with a threshold value;
Control means for controlling the conveyance of the object to be inspected by the conveyance means based on the determination by the processing determination means;
6. The inspection apparatus according to claim 5, further comprising: An input device for inputting the threshold;
A storage device for storing the input threshold value;
A display device for displaying the stored threshold value;
The inspection apparatus according to claim 6, further comprising:   The inspection apparatus according to claim 5, further comprising a reversing unit that reverses the front and back surfaces of the object to be inspected. The said detector measures the distance of the said stage and the said to-be-inspected object in two or more places using the said light beam, and measures the said curvature amount using the difference. The inspection apparatus in any one of. The inspection apparatus according to claim 5, wherein the support means supports the lower surface of the edge of the object to be inspected by three support portions.

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