JP3941375B2 - Substrate periphery inspection method, electronic substrate manufacturing method, and substrate periphery inspection apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate peripheral inspection method, an electronic substrate manufacturing method, and a substrate peripheral inspection device, and in particular, in the manufacture of an electronic substrate that requires highly accurate film formation processing and etching processing, The present invention relates to an inspection method for accurately detecting an exposed width of a lower ground, an electronic substrate manufacturing method to which the inspection method is applied, and a substrate peripheral edge inspection apparatus for performing the inspection method.
[0002]
[Prior art]
In recent years, as semiconductor devices are highly integrated, device structures are becoming more complicated. In particular, in order to form a system LSI such as DRAM-embedded Logic on a substrate made of silicon, many processes such as film formation, lithography, and dry etching are performed, and processes of several hundred processes are complicatedly intertwined.
[0003]
By the way, the edge of the processed film such as an insulating film or a conductive film formed on the substrate is turned up at the peripheral portion of the substrate after a plurality of processes, or a part of these processed films is detached. It is in a very unstable state, and it is one of the sources of dust generation. Therefore, in manufacturing an electronic substrate such as a semiconductor wafer, in order to remove such a dust generation source, it is considered to perform a step of etching and removing the peripheral portion of the processed film along the peripheral edge of the substrate.
[0004]
Further, when the element structure in a semiconductor device is further miniaturized and the design rule is 0.13 μm or later, Cu (copper), Ru (ruthenium), Ta (tantalum) are used to realize higher functionality of the semiconductor device. The use of dissimilar metals such as these is planned, and there is concern about contamination by these metals. Among them, it is known that contamination due to Cu in particular has an adverse effect on device characteristics. ¹⁵ atoms / cm ^Three The occurrence of junction leakage, n ⁺ Degradation occurs in the characteristics of the semiconductor device, such as variations in gate breakdown voltage, subthreshold swing value (so-called S value), and threshold voltage.
[0005]
For this reason, after forming the Cu film, it is generally performed to remove Cu from the back surface of the substrate or to remove the Cu film at the peripheral portion or bevel portion of the substrate by wet etching. It's getting on.
[0006]
Removal of the peripheral portion of the processed film as described above by wet etching is often realized by using a single-wafer type wet etching apparatus. However, when such a process is introduced into the manufacturing process of a semiconductor device, it is necessary to keep etching on the outer circumference rather than in the substrate acquisition area (for example, in the chip area in the case of a semiconductor wafer) in order to secure the yield. In addition, in order to reliably remove the peripheral portion of the processed film that becomes a contamination source, it is necessary to remove the processed film having a predetermined width or more from the peripheral edge of the substrate. The uniformity of the etching removal width for the wafer is required.
[0007]
For this reason, in the evaluation of this process, it is necessary to measure the width of the processed film removed by wet etching over the entire circumference of the substrate and to examine the process based on this measurement value.
[0008]
[Problems to be solved by the invention]
However, at present, there is no technique for measuring the exposed width of the ground plane such as the removal width of the processed film at the peripheral edge of the substrate. For example, by using a measuring jig such as a vernier caliper, the substrate is directly or microscopically photographed. The measurement is performed manually above.
[0009]
In such manual measurement, it is very difficult to obtain the measurement accuracy of the exposed width of the base surface, and also the measurement position accuracy on the substrate, and discuss the uniformity of the etching removal width from such measurement results. Is in a difficult situation. In addition, since the measurement is performed manually, a certain amount of time is required. When the time required for measurement increases as the substrate diameter increases, this measurement process becomes a very laborious work process.
[0010]
Therefore, the present invention provides a substrate periphery inspection method capable of measuring the exposed width of the processed film base surface along the periphery of the substrate with high accuracy and at high speed, and also using this substrate periphery inspection method It is an object of the present invention to provide an electronic substrate manufacturing method capable of accurately uniforming the exposed width of the processed film base surface at the periphery of the substrate, and to provide a substrate periphery inspection apparatus that realizes the substrate periphery inspection method.
[0011]
[Means for Solving the Problems]
In order to achieve such an object, the substrate periphery inspection method of the present invention is a substrate that measures the exposed width of the base surface exposed along the periphery of the substrate from the periphery of the processed film formed on the substrate. This is a peripheral inspection method and is performed as follows. First, a measurement region is set in the peripheral portion of the substrate including the peripheral edge of the substrate and the peripheral edge of the processed film, and image data of the measurement region is captured. Next, the brightness of each pixel arranged on a virtual line perpendicular to the periphery of the substrate is detected in the image data, and two locations where the change in brightness is greater than a predetermined value are extracted. And the space | interval of these two places is calculated | required as an exposed width of the base surface on a virtual line.
[0012]
In such a substrate periphery inspection method, image data of a measurement region including the periphery of the substrate is captured. In this image data, a difference in the luminance of each pixel can be caused by a difference in surface material. For this reason, by extracting two places where the luminance change between the pixels arranged on the virtual line is larger than a predetermined value, the boundary between the outer periphery of the substrate and the base surface and the boundary between the base surface and the processed film Is extracted, and the exposed width of the base surface can be obtained. In addition, since the above two locations are extracted in a virtual line shape perpendicular to the periphery of the substrate on the image data, this virtual line is set in the width direction of the base surface exposed along the periphery of the substrate. Therefore, measurement is always performed in a certain direction. Therefore, the exposed width of the base surface along the periphery of the substrate can be obtained with high accuracy by processing the image data.
[0013]
In this inspection method, first, a portion serving as a base point on the periphery of the substrate may be found, and then image data of a measurement region that is separated from the base point by a predetermined distance along the periphery may be captured. In this way, the exposed width of the processed film base surface is always obtained at a fixed position, and the measurement position accuracy between the substrates can be obtained.
[0014]
In the method for manufacturing an electronic substrate according to the present invention, after forming a processed film in a state of covering the substrate surface, the exposed width of the processed film base surface is obtained by the above-described inspection method, and then this exposed width is an intended target width. The process film formation conditions are adjusted so as to match the above.
[0015]
In such a manufacturing method, the exposed width of the processed film base surface is obtained in the same manner as the above-described inspection method, and the formation conditions of the processed film are adjusted so that the exposed width matches the intended target width. Therefore, the formation condition of the processed film is adjusted based on the highly accurate measurement result. Therefore, it is possible to more accurately obtain the processing film forming conditions that match the exposed width of the processing film base surface with the target width.
[0016]
Furthermore, the substrate periphery inspection device of the present invention is a substrate periphery inspection device for measuring the exposed width of the base surface exposed along the periphery of the substrate from the periphery of the processed film formed on the substrate, A stage for placing the substrate, a camera for setting the measurement region in the main part of the substrate including the periphery of the substrate placed on the stage and the periphery of the processed film, and capturing the image data; An image processing unit for processing the captured image data. The image processing unit detects the luminance of each pixel arranged on a virtual line perpendicular to the periphery of the substrate in the captured image data, extracts two locations where the luminance change is greater than a predetermined value, and extracts the interval Is determined as the exposure width. Furthermore, a controller is provided that moves the stage or the camera so that image data of a measurement area that is separated from the base point set at the peripheral edge of the substrate by a predetermined distance along the peripheral edge of the substrate is captured.
[0017]
Such a substrate periphery inspection apparatus includes an image processing unit that obtains the exposed width of the processed film base in the same procedure as the above-described substrate periphery inspection method based on image data captured from the camera. It is possible to automatically and accurately measure the exposed width of the processed film base in the portion. In addition, since the stage or the camera is moved by the controller so that the image data of the predetermined measurement area is captured, the measurement position accuracy can be obtained.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Here, in the manufacture of an electronic substrate such as a semiconductor wafer, the method of manufacturing the electronic substrate and the substrate periphery of the present invention include the step of removing the peripheral portion of the processed film formed to cover the substrate surface with a predetermined target width. An embodiment to which the inspection method is applied will be described. The present invention is not limited to the application to the production of a semiconductor wafer (semiconductor device substrate), and uses various substrates such as a magnetic substrate, a dielectric substrate, a metal substrate, a plastic substrate, etc. Needless to say, the present invention is widely applied to the production of electronic substrates obtained by processing (for example, the production of liquid crystal substrates).
[0019]
First, as shown in FIG. 1, a processed film 2 is formed on the surface side of the substrate 1 by a film forming method such as a CVD method. Here, for example, a processed film 2 made of silicon oxide is formed on the surface of the substrate 1 made of silicon by a thermal oxidation method.
[0020]
Next, the peripheral portion of the processed film 2 is removed with a predetermined target width along the peripheral edge of the substrate 1, that is, the lower ground 1 a (here, the silicon surface) of the processed film 2 along the peripheral edge of the substrate 1 is intended. It is exposed with a width D.
[0021]
Here, for example, as shown in FIG. 2, the substrate 1 is rotated and held with the surface (front surface side) on which the processed film 2 is formed facing downward and the back surface side facing upward. While blowing an inert gas 3 such as nitrogen gas to the center position, hydrofluoric acid (HF) is supplied as the etchant 4 to the center position on the back surface of the substrate 1. Thus, while protecting the front surface side of the substrate 1 with the inert gas 3, the back surface side is covered with the etching solution 4, and the etching solution 4 is circulated to the peripheral portion on the front surface side of the substrate 1. The film 2 is removed by etching. At this time, the removal width of the processed film 2, that is, the exposure of the lower ground 1 a of the processed film 2, is adjusted by adjusting the etching conditions such as the supply amount of the etching solution 4, the rotation speed of the substrate 1, and the supplied amount of the inert gas 3. The width d is made to coincide with the target width D.
[0022]
Next, on the substrate 1 from which the peripheral portion of the processed film 2 has been removed in this way, the exposed width d of the lower ground 1a of the processed film 2 is measured. FIG. 3 is a flowchart showing an example of this exposure width d measuring method, that is, a substrate peripheral edge inspection method, and FIG. 4 is a diagram for explaining this method in more detail. Below, an example of the procedure of the board | substrate periphery test | inspection method is demonstrated based on these figures.
[0023]
First, in step S <b> 11, a portion that becomes the base point 5 on the periphery of the substrate 1 is searched. Here, for example, the notch formed in the substrate 1 is set as the base point 5. The base point 5 is not limited to a notch as long as it indicates a position common to each substrate 1. When the orientation flat is provided on the substrate 1, one end portion or the central portion of the orientation flat is provided. Etc. may be used as a base point.
[0024]
Next, in step S <b> 12, the first measurement region A <b> 1 is set in a peripheral portion separated from the base point 5 by a predetermined distance along the peripheral edge of the substrate 1. Here, since the semiconductor wafer is the substrate 1, for example, a virtual line L1 obtained by rotating a straight line L0 connecting the base point 5 and the center O of the substrate 1 clockwise by a predetermined angle θ1 is set. And the point on the periphery of the board | substrate 1 on this virtual line L1 is made into the 1st measurement point P1, and the area | region including this 1st measurement point P1 and the periphery of the process film 2 of this periphery is set as 1st measurement area | region A1. .
[0025]
Next, in step S13, the image data of the first measurement area A1 is captured. At this time, the area for capturing image data (that is, the first measurement area A1) is set to 14.7 mm in the horizontal direction × 11.0 mm in the vertical direction when the substrate 1 is a wafer substrate having a diameter of 200 mm, for example.
[0026]
Further, the brightness of each pixel constituting the image data is significantly different between the processed film 2 portion and the base surface 1a portion, and between the base surface 1a portion and the outer peripheral portion of the substrate 1, A primary light source for obtaining image data is adjusted.
[0027]
Specifically, depending on the material of the processed film 2 and the underlying surface 1a portion, the image is set so that a difference in luminance of each pixel constituting the image data is likely to occur or the difference is not excessively large. If the data is an optical image, select the coaxial illumination or shading illumination as the primary light source and adjust the amount of light, and if the image data is a secondary electron image or reflected electron image, adjust the aperture of the electron beam that is the temporary light source I decided to.
[0028]
Next, in step S14, in the image data of the first measurement region A1, a virtual line perpendicular to the peripheral edge of the substrate 1 (that is, a straight line L0 connecting the base point 5 and the center O of the substrate 1 is rotated clockwise by a predetermined angle θ1). The brightness of each pixel arranged on the rotated virtual line L1 is detected, and two locations where the brightness change in each pixel on the virtual line L1 is larger than a predetermined value are extracted from this brightness.
[0029]
Here, FIG. 5 shows a cross-sectional view of the imaginary line L1 portion in the peripheral portion of the substrate 1. FIG. As shown in this cross-sectional view, the film thickness of the peripheral portion of the processed film 2 etched away along the peripheral edge of the substrate 1 is gradually reduced. The peripheral portion of the substrate 1 is formed as a bevel surface that is rounded toward the peripheral edge.
[0030]
The graph of FIG. 6 shows an example of the luminance of each pixel on the virtual line L1 from the outer peripheral portion of the substrate 1 toward the center. As shown in this graph, there is a difference in the luminance of each pixel between the outer periphery of the substrate 1, the substrate 1, that is, the base surface 1a, and the processed film 2, and the luminance is significantly different at the boundary portion of these materials. To change. This is because the image data is captured so that significant differences occur between the outer peripheral portion of the substrate 1 and the base surface 1a portion and between the base surface 1a portion and the processed film 2 portion when the image data is captured in step S13. This is because the primary light source for obtaining data is adjusted. Therefore, two boundary points p11 and p12 where the luminance change is larger than a predetermined value are extracted to find these boundary portions.
[0031]
However, as shown in FIG. 5, since the change in luminance may be gradual due to the gradual inclination of the peripheral portion of the substrate 1 or the peripheral portion of the processed film 2, the threshold value th <b> 1 is previously set. , Th2 may be set, and the points reaching the threshold values th1, th2 may be set as the change points p11, p12.
[0032]
At this time, as a method for digitally processing the luminance of each pixel, for example, processing using an 8-bit gray code is performed. Then, the change points p11 and p12 are extracted from the center side or the outer periphery side of the substrate 1. Further, in order to speed up the extraction, a luminance change point may be searched from both ends of the virtual line L1. As a result, the extraction speed of the change points p11 and p12 is reduced to about ½.
[0033]
After the above, in step S15 shown in FIG. 3, the interval between the two extracted change points p11 and p12 is obtained as the exposure width d of the base surface 1a on the virtual line L1 passing through the first measurement point P1. At this time, for example, the exposure width d is obtained from the number of pixels between the change points p11 and p12 and the pixel size.
[0034]
As described above, in steps S14 and S15, the exposure width d is obtained only on the virtual line L1. However, in the image data of the first measurement area A1, a plurality of virtual lines L having a slight deviation from the virtual line L1 are assumed, and the exposure width is also set on these virtual lines L in the same manner as described above. You may ask for each.
[0035]
After the above, in step S16, it is determined whether or not there is a next measurement. If it is determined that there is the next measurement, the process returns to step S12, and the second measurement region A2 is set along the peripheral edge of the substrate 1 at a peripheral portion that is a predetermined distance away from the base point 5. Here, a straight line obtained by rotating a straight line L0 connecting the base point 5 and the center O of the substrate 1 clockwise by a predetermined angle θ2 is set as a virtual line L2, and points on the periphery of the substrate 1 on the virtual line L2 are set. A second measurement point P2 is set, and a region including the second measurement point P2 and the peripheral edge of the peripheral processed film 2 is set as a second measurement region A2.
[0036]
Thereafter, Steps S13 to S16 are repeated in the same manner as described above, the exposure width d is measured in the plurality of measurement regions A1 to An along the periphery of the substrate 1, and a series of processes is performed when all the measurements are completed. End.
[0037]
After obtaining the exposure width d in each measurement region Ax (x = 1 to n) as described above, the measured values of these exposure widths d are used as information about one substrate 1 to each virtual line Lx (x = 1-n) Data is saved in CSV format (Comma Separates Value format) corresponding to the angle θx (x = 1 to n) formed by the position, that is, the straight line L0 connecting the base point 5 and the center O, 1: 1. Keep it. Then, statistical processing such as uniformity of the exposure width d over the entire circumference of the substrate 1 is performed.
[0038]
Further, in each measurement area Ax, a plurality of virtual lines L having a slight deviation from the virtual line measurement L1 are assumed in each image data A1, and the exposure width is similarly applied to these virtual lines L. When each is obtained, these values are also stored in the same manner. Then, the plurality of exposure widths d obtained for each measurement region Ax are statistically processed to obtain one exposure width d for each measurement region Ax. For example, out of a plurality of exposure widths obtained for a certain measurement area Ax, the average value is calculated by removing the maximum value and the minimum value, and this average value is set as the exposure width d in the measurement area Ax. By doing in this way, it becomes possible to reject noise and a jump value, and it is possible to improve the reliability of the exposure width d obtained for each measurement region Ax.
[0039]
FIG. 7 shows a graph of the exposure width d measured in each measurement region Ax in which the angle θx is changed by 15 ° by the above procedure. The measurement accuracy was ± 50 μm, and in the image processing, the exposure width d was obtained with a processing time of 0.5 seconds for one measurement region Ax.
[0040]
Next, in the removal process of the peripheral portion of the processed film described with reference to FIG. 2 based on the statistically processed data, the removal width of the processed film 2 (that is, the base surface 1a) over the entire periphery of the substrate 1 is described. The etching conditions such as the supply amount of the inert gas 3, the supply amount of the etching solution 4, and the number of rotations of the substrate 1 are readjusted so that the exposure width d) matches the target width D. Thereafter, the peripheral portion of the processed film 2 is etched under the readjusted etching conditions.
[0041]
In the electronic substrate manufacturing method described above, the exposure width d is obtained by image processing of image data in an inspection for measuring the exposure width d of the base surface at the periphery of the substrate. At this time, since the virtual line Lx perpendicular to the periphery of the substrate 1 is set on the image data, the virtual line Lx is formed in the width direction of the base surface 1a exposed along the periphery of the substrate 1. Will be set. For this reason, the exposure width d of the base surface 1a along the peripheral edge of the substrate 1 can be automatically obtained with high accuracy by processing the image data.
[0042]
Since the processing film forming conditions are adjusted so that the exposure width d obtained by such an inspection method matches the intended target width D, the processing film 2 is based on a highly accurate measurement result. The formation conditions (for example, etching conditions) are adjusted. For this reason, it is possible to more accurately obtain the formation conditions of the processed film 1 such that the exposed width d of the lower ground 1a of the processed film 1 matches the target width D. Therefore, for example, it is possible to perform etching with the removal width of the processed film 2 along the peripheral edge of the substrate 1 controlled with high accuracy, and etching into the acquisition region of the substrate 1 (for example, in the chip region in the case of a semiconductor wafer). It is possible to reliably remove the edge portion of the processed film 1 serving as a contamination source while preventing the film from being covered. As a result, the yield of the semiconductor device can be improved.
[0043]
In the above-described embodiment, as shown in the flowchart of FIG. 3, every time each measurement region Ax is set (step S12), the image data is fetched (step S13) to the exposure width d is obtained (step The procedure up to and including S15) is described. However, as shown in the flowchart of FIG. 8, the substrate periphery inspection method of the present invention searches for a base point (for example, a notch) at the periphery of the substrate (step S21), and then sets the measurement region Ax for all the measurement regions Ax. (Step S22) and taking in image data (Step S23), extracting two luminance change points in each image data (Step S25), and further obtaining each exposure width d (Step S26) You may make it do.
[0044]
In the above-described embodiment, the method in which the present invention is applied to the step of etching and removing the processed film 2 with a predetermined width along the periphery of the substrate 1 in the manufacture of the electronic substrate has been described. However, the electronic substrate manufacturing method and substrate peripheral edge inspection method of the present invention can also be applied to the step of forming the processed film 2 on the substrate 1 by the CVD method, the PVD method, the spin coating method, or other film forming methods. It is also possible to measure the exposed width of the base at the periphery of the processed film 2 formed by such a film forming method and adjust the film forming conditions based on the measurement result.
[0045]
Next, the configuration of the substrate periphery inspection apparatus used in the above-described substrate periphery inspection method will be described. FIG. 9 is a configuration diagram illustrating an example of a substrate peripheral edge inspection apparatus. The substrate periphery inspection apparatus shown in FIG. 1 includes a stage 21 on which a substrate 1 is placed, a camera 23 that captures image data of a measurement area Ax (x = 1 to n) of the substrate 1 placed on the stage 21, An image processing unit 25 that processes image data captured from the camera and a table controller 27 that drives the stage 21 are provided.
[0046]
The stage 21 can freely rotate and move in the XY directions while holding the surface of the substrate 1 placed thereon horizontally, and the movement of the stage 21 is controlled by the table controller 27.
[0047]
The camera 23 is provided above the stage 21 so as to be fixed toward the stage 21 side. As shown in FIG. 10, the camera 23 includes, for example, a CCD camera (progressive scan camera) 23 provided with an optical system lens. A coaxial illumination 31 and a dark field illumination 33 are illuminated between the subject and the CCD camera 23. It is arranged as a primary light source, and is configured to capture images in both bright and dark fields.
[0048]
Then, the image processing unit 25 performs the processing described with reference to steps S14 and S15 of the flowchart of FIG. 3 or the steps of the flowchart of FIG. The process described using S25 and step S26 is performed.
[0049]
In addition, the table controller 27 drives the stage 21 so that the measurement region in the above-described substrate periphery inspection method is within the fixed visual field of the camera 23. In this case, the substrate 1 is placed on the stage 21 in a predetermined state such that the center of rotation of the stage 21 and the center of the substrate 1 coincide. Then, the driving of the stage 21 is started from a state in which the base point 5 (notch) on the periphery of the substrate 1 is placed near the center of the field of view of the camera 23.
[0050]
Here, when the substrate 1 is a circular substrate such as a semiconductor wafer, the stage 21 is rotated by a predetermined angle from the state in which the base point 5 is placed near the center of the field of view of the camera 23, and the measurement region Ax is the camera. It matches or falls within the field of view of 23. However, if there is a straight portion such as an orientation flat on the periphery of the circular substrate, the stage 21 is moved by a predetermined distance in the XY direction in this straight portion.
[0051]
Further, when the substrate is a rectangular substrate, the stage 21 is moved by a predetermined distance in the XY direction from the state where the base point is placed near the center of the field of view of the camera 23, and the measurement region is within the field of view of the camera 23. To enter.
[0052]
Further, the table controller 27 and the camera 23 are interlocked, and the image data is captured by the camera 23 in a state where the stage 21 is driven by the stage controller 27 to a position where a predetermined measurement area is within the visual field of the camera 23. Further, it is assumed that the stage 21 is driven so that the next measurement area is within the field of view of the camera 23 after the image data has been captured.
[0053]
The substrate periphery inspection apparatus configured as described above includes an image processing unit that determines the exposed width of the base of the processed film based on the image data captured from the camera 23 in the same procedure as the above-described substrate periphery inspection method. Therefore, it becomes possible to automatically and accurately measure the base exposure width d of the processed film 2 at the peripheral edge of the substrate 1. In addition, since the stage controller 27 for driving the stage 21 on which the substrate 1 is placed is provided, it is possible to capture image data at a plurality of predetermined positions on the substrate 1 and improve the measurement position accuracy. Can be achieved.
[0054]
In the substrate periphery inspection apparatus according to this embodiment, the stage 21 is moved with respect to the fixed camera 23 by providing the table controller 27. However, if a plurality of measurement regions Ax along the periphery of the substrate 1 can be sequentially placed in the field of view of the camera 23, a configuration in which a controller for moving the camera 23 relative to the fixed stage 21 is provided, the stage 21 And the structure which provided the controller which drives both the camera 2 may be sufficient.
[0055]
【The invention's effect】
As described above, according to the substrate periphery inspection method of the present invention, the boundary of different materials is extracted by processing image data, and the exposed width of the base along the substrate periphery is obtained. In addition, the exposed width of the base surface along the periphery of the substrate can be obtained at high speed. In addition, since the exposed width of the processed film base surface can always be obtained at a fixed position, the measurement position accuracy between the substrates can be improved.
[0056]
Then, according to the electronic substrate manufacturing method of the present invention for performing such a substrate inspection method, the processing film formation conditions are set so that the exposure width obtained with high accuracy as described above matches the intended target width. Therefore, it is possible to more accurately obtain the formation condition of the processed film so that the exposed width of the processed film base surface matches the target width. Therefore, the exposed width of the processed film base surface at the periphery of the substrate can be made uniform with high accuracy. As a result, for example, the edge portion of the processed film 1 that becomes a contamination source can be removed in a state in which the inside of the acquisition area of the substrate 1 (for example, the chip area in the case of a semiconductor wafer) is reliably covered with the processed film. Thus, it becomes possible to improve the yield of electronic substrates.
[0057]
Furthermore, according to the substrate periphery inspection apparatus of the present invention, the image processing unit that obtains the exposed width of the processed film base in the same procedure as the above-described substrate periphery inspection method based on the image data captured from the camera is provided. The exposure width can be measured with high accuracy and automatically. In addition, since the stage or the camera can be moved by the controller so that the image data of a predetermined measurement area is captured, it is possible to increase the speed of capturing a plurality of image data while ensuring the measurement position accuracy. Become. Therefore, it is possible to realize high speed and automation of the above-described substrate periphery inspection method of the present invention.
[Brief description of the drawings]
FIG. 1 is a plan view of an electronic substrate formed by etching and removing a peripheral portion of a processed film.
FIG. 2 is a diagram illustrating an example of an etching process in manufacturing an electronic substrate.
FIG. 3 is a flowchart showing a substrate peripheral edge inspection method in manufacturing an electronic substrate according to the present invention.
FIG. 4 is a diagram for explaining a substrate peripheral edge inspection method in detail.
FIG. 5 is a cross-sectional view of the main part of the substrate for explaining the substrate periphery inspection method in detail.
FIG. 6 is a graph showing a relationship between a pixel position on an imaginary line and luminance for explaining the substrate peripheral edge inspection method in detail.
FIG. 7 is a graph showing the exposed width of the base surface at the peripheral edge of the substrate.
FIG. 8 is a flowchart showing another example of a substrate peripheral edge inspection method in manufacturing an electronic substrate according to the present invention.
FIG. 9 is a configuration diagram of a substrate periphery inspection apparatus for performing the substrate periphery inspection method of the present invention.
10 is a configuration diagram of a camera used in the substrate peripheral edge inspection apparatus in FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 1a ... Base surface, 2 ... Processed film, 5 ... Base point, 21 ... Stage, 23 ... Camera, 25 ... Image processing part, 27 ... Table controller, 31 ... Coaxial illumination (primary light source), 33 ... Oblique illumination (Primary light source), d ... exposure width, Ax (x = 1 to n) ... measurement region, L, Lx (x = 1 to n) ... virtual line

Claims (8)

A substrate periphery inspection method for measuring the exposed width of a base surface exposed along the periphery of the substrate from the periphery of the processed film formed on the substrate,
Setting a measurement region in the peripheral portion of the substrate including the peripheral edge of the substrate and the peripheral edge of the processed film, and capturing image data of the measurement region;
Detecting the brightness of each pixel arranged on a virtual line perpendicular to the periphery of the substrate in the image data, and extracting two locations where the change in brightness is greater than a predetermined value;
And a step of determining the interval between the two extracted positions as the exposure width on the virtual line. The substrate periphery inspection method according to claim 1,
In the step of capturing the image data, between the luminance of each pixel of the processed film portion and the luminance of each pixel of the base surface portion, and the luminance of each pixel of the base surface portion and each pixel of the outer peripheral portion of the substrate A substrate peripheral inspection method, comprising: adjusting a primary light source for collecting the image data so that a difference occurs between the brightness and the brightness of the image data. The substrate periphery inspection method according to claim 1,
In the step of capturing the image data, first, a portion serving as a base point is searched for at the periphery of the substrate, and then image data of a measurement region that is separated from the base point by a predetermined distance along the periphery of the substrate is captured. Perimeter inspection method. The substrate periphery inspection method according to claim 3,
The substrate peripheral inspection method, wherein the measurement areas are set at a plurality of locations separated from the base point by different distances. The substrate periphery inspection method according to claim 1,
A plurality of the virtual lines are set in the image data, and a plurality of exposure widths obtained on the virtual lines are statistically processed to obtain an exposure width of the measurement region. . Forming a processed film in a state of covering the substrate surface;
Setting a measurement region in the peripheral portion of the substrate including the peripheral edge of the substrate and the peripheral edge of the processed film, and capturing image data of the measurement region;
Detecting the brightness of each pixel arranged on a virtual line perpendicular to the periphery of the substrate in the image data, and extracting two locations where the change in brightness is greater than a predetermined value;
A step of obtaining an interval between the extracted two locations as an exposed width of the lower ground of the processed film on the virtual line;
And a step of adjusting a forming condition of the processed film so that the exposed width coincides with an intended target width. A substrate periphery inspection apparatus for measuring an exposed width of a base surface exposed along the periphery of the substrate from the periphery of the processed film formed on the substrate,
A stage on which the substrate is placed;
A camera that captures image data by setting a measurement region in the peripheral portion of the substrate including the peripheral edge of the substrate placed on the stage and the peripheral edge of the processed film;
Based on the image data captured from the camera, the brightness of each pixel arranged on a virtual line perpendicular to the periphery of the substrate in the image data is detected, and the change in brightness is less than a predetermined value. An apparatus for inspecting a peripheral edge of a substrate, comprising: an image processing unit that extracts two large locations and obtains the interval as the exposure width on the virtual line. In the board | substrate periphery test | inspection apparatus of Claim 7,
A substrate comprising: a controller for moving the stage or the camera so that image data of a measurement region separated from the base point set at the periphery of the substrate by a predetermined distance along the periphery of the substrate is captured. Perimeter inspection device.

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