JP7106608B2 - Mark detection device, alignment device, film formation device, mark detection method, and film formation method - Google Patents

Description

The present invention relates to a mark detection device.

2. Description of the Related Art There is a mark detection device that detects a mark provided on a board or the like from image data obtained by photographing the board or the like. Such a mark detection apparatus is used, for example, in an alignment apparatus for aligning a substrate and a mask, which is provided in a film forming apparatus for forming a film of a film forming material on a substrate through a mask. be done. Such an alignment apparatus picks up images of a substrate and a mask, detects substrate marks provided on the substrate and mask marks provided on the mask, and moves the substrate or mask so that the distance between the marks satisfies a predetermined relationship. alignment. At this time, in order to improve alignment accuracy, it is necessary to extract substrate marks and mask marks from the captured image as accurately as possible.

An example of such a film forming apparatus is an organic semiconductor manufacturing apparatus used for manufacturing organic semiconductors. In the manufacture of organic semiconductors, substrate alignment marks (substrate marks) are formed on a wafer substrate of silicon or the like by laser processing. Then, a mask having a desired pattern is brought close to the substrate, and alignment is performed based on the positional relationship between the alignment marks (mask marks) formed on the mask and the substrate marks.

Another example of the film forming apparatus is an organic EL film forming apparatus for manufacturing an organic EL display device. In the case of an organic EL display, a mask on which a pixel pattern is formed is aligned with a substrate such as glass in a film forming apparatus. forming an electrode metal layer;
In order to form a film with high precision in such a film forming apparatus, it is necessary to align the substrate and the mask with high precision.

Patent Document 1 (Japanese Patent Application Laid-Open No. 2019-179186) describes a technique using alignment marks formed on a substrate by laser processing. That is, in Patent Document 1, alignment marks are formed by irradiating a substrate with a spot-shaped light beam using a laser, and alignment is performed using an image obtained by photographing a region including the alignment marks.

JP 2019-179186 A

In order to improve the alignment accuracy between the substrate and the mask, it is required to detect substrate marks with higher accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for improving detection accuracy of marks formed on a substrate for alignment.

The present invention employs the following configurations. i.e.
A mark detection device for detecting an alignment mark,
a photographing means for obtaining a photographed image by photographing an area including the alignment mark;
detection means for comparing the photographed image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
The detection means compares a portion of the alignment mark excluding an end portion of the linear portion with the model image.
This mark detection device is characterized by:
The present invention also employs the following configurations. i.e.
A mark detection device for detecting an alignment mark,
a photographing means for obtaining a photographed image by photographing an area including the alignment mark;
detection means for comparing the photographed image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
the model image includes a linear model portion corresponding to the linear portion of the alignment mark;
The length of the linear model portion of the model image is shorter than the length of the linear portion of the alignment mark.
This mark detection device is characterized by:
The present invention also employs the following configurations. i.e.
A mark detection method for detecting an alignment mark, comprising:
a photographing step of obtaining a photographed image by photographing an area including the alignment mark;
a detection step of comparing the captured image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
The detection step includes a comparison step of comparing a portion of the alignment mark excluding an end portion of the linear portion with the model image.
This mark detection method is characterized by:
The present invention also employs the following configurations. i.e.
A mark detection method for detecting an alignment mark, comprising:
a photographing step of obtaining a photographed image by photographing an area including the alignment mark;
a detection step of comparing the captured image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
the model image includes a linear model portion corresponding to the linear portion of the alignment mark;
The length of the linear model portion of the model image is shorter than the length of the linear portion of the alignment mark.
This mark detection method is characterized by:

According to the present invention, it is possible to provide a technique for improving detection accuracy of marks formed on a substrate for alignment.

Schematic diagram of an electronic device production line including film deposition equipment Cross-sectional view showing the internal configuration of the deposition apparatus Diagram explaining mark detection and alignment Diagram showing the bulge at the end of the board mark and the model board mark Flow chart explaining the flow of film formation processing from mark detection FIG. 4 is a diagram for explaining correction of the model board mark in the embodiment; A diagram showing another form of the board mark Diagram explaining multiple modified model board marks

Preferred embodiments of the present invention will be described below with reference to the drawings. However, the following description merely exemplifies preferred configurations of the present invention, and the scope of the present invention is not limited to those configurations. In addition, unless otherwise specified, the hardware configuration and software configuration of the apparatus, processing flow, manufacturing conditions, dimensions, materials, shapes, etc. in the following description are intended to limit the scope of the present invention. do not have.

Here, when forming a film having a desired shape on a substrate, a mask having a mask pattern suitable for the shape of the film to be formed is used. Thereby, each layer to be deposited can be arbitrarily configured. In order to form a film at a desired position on the substrate, it is necessary to precisely align the relative positions of the substrate and the mask. At the time of alignment, an image of an alignment mark (substrate mark) formed on a substrate and an alignment mark (mask mark) formed on a mask is normally captured by a photographing means such as a camera, and alignment is performed by an alignment means such as an actuator. That is, for good alignment, it is preferable that at least substrate marks and mask marks can be detected with high accuracy.

INDUSTRIAL APPLICABILITY As described above, the present invention is preferably used in techniques for detecting alignment marks (substrate marks and/or mask marks). Therefore, the present invention can be regarded as a mark detection device or a mark detection method. The present invention can also be viewed as an alignment apparatus or alignment method for aligning a substrate and a mask using detected marks. The present invention can also be regarded as a film forming apparatus or film forming method using such an alignment apparatus or alignment method. The present invention can also be regarded as an electronic device manufacturing apparatus or an electronic device manufacturing method using such a film forming apparatus or film forming method.

INDUSTRIAL APPLICABILITY The present invention can be preferably applied when forming a thin film material layer with a desired pattern on the surface of a substrate through a mask. Any material such as silicon, glass, resin, or metal can be used as the material of the substrate. Any material such as an organic material or an inorganic material (metal, metal oxide) can be used as the film-forming material. The technology of the present invention is typically applied to electronic device and optical member manufacturing apparatuses. The present invention can be applied to, for example, an organic semiconductor manufacturing apparatus and an organic semiconductor manufactured using the same. The present invention is also suitable for organic electronic devices such as an organic EL display, a manufacturing apparatus for an organic EL display device using the same, a thin film solar cell, and an organic CMOS image sensor.

<Examination of conventional technology>
As a result of diligent studies by the inventors, it was found that there is a possibility that the accuracy of substrate mark detection may deteriorate in the conventional technique.

FIG. 3 is a diagram for explaining detection of board marks. Here, a case of forming a substrate mark on a wafer substrate by laser processing will be taken as an example.
FIGS. 3(a) and 3(b) are ideal diagrams according to the conventional example, respectively an ideally formed board mark 104 and an internal model for detecting the board mark 104. FIG. A model board mark 174 is shown. The model board mark 174 is a model image showing the shape of the board mark, and is stored in the storage means. FIG. 3(c) is a diagram showing a state in which the board mark 104 and the mask mark 224 are included in the imaging area.

A case where board mark detection is performed using the board mark 104 in FIG. 3A and the model board mark in FIG. 3B will be described. The mark detection device compares the data of the board mark 104 in the imaging area 264 captured by the imaging means with the model board mark 174 by an image recognition algorithm such as pattern matching. When a board mark 104 matching the shape of the model board mark 174 is detected, the mark detection device stores the position of the detected board mark 104 as coordinates. When the mark detection device detects the mask mark 224, the alignment device aligns the substrate and the mask.

On the other hand, FIG. 4A is a diagram showing an actual linear substrate mark formed by processing a wafer substrate using laser processing technology according to the conventional example.
In this case, the central portion 104m of the board mark has the same thickness as the ideal board mark, but the end portion 104t of the board mark may have a swollen shape. That is, in a linear mark, the thickness of the line in the first area near the end of the line may be larger than the thickness of the line in the second area other than the vicinity of the end. Although the extent and shape of the bulging of the end portion (first region) 104t with respect to the central portion (second region) 104m varies depending on the material and processing method of the substrate, the occurrence of such bulging affects the accuracy of mark detection. may give.

That is, even if the board mark 104 having the shape shown in this figure is detected by matching with the model board mark 174 shown in FIG. do not do. Therefore, there is a possibility that the accuracy of recognizing the board mark 104 will be lowered, or that the accuracy of coordinates during position detection will be lowered. As a result, there is a possibility that the accuracy of alignment will be degraded.

Therefore, in the following description, an embodiment will be described in which it is possible to satisfactorily detect even a board mark whose end portion is deformed such as a bulge. The present invention is not limited to the case of laser processing a wafer, but can be applied to the case where bulging or deformation occurs at the end portion due to the influence of processing when forming marks on at least one of a substrate and a mask.

<Example 1>
(Electronic device manufacturing line)
FIG. 1 is a plan view schematically showing the configuration of a manufacturing line for electronic devices. Such a production line is a film forming system including a film forming apparatus. Here, a manufacturing line for an organic EL display will be described. When manufacturing an organic EL display, a substrate of a predetermined size is carried into the manufacturing line, and after the organic EL and metal layers are formed, post-processing such as cutting the substrate is performed.

As shown in FIG. 1, the film formation cluster 1 of the production line includes a transfer chamber 130 arranged in the center, and a film formation chamber 110 and a mask stock chamber 120 arranged around the transfer chamber 130 . A film forming chamber 110 includes a film forming apparatus, and a film forming process is performed on the substrate 10 . A mask stock chamber 120 stores masks before and after use.

A transport robot 140 installed in the transport chamber 130 loads the substrate 10 and the mask 220 into and out of the transport chamber 130 . The transport robot 140 is, for example, a robot in which a robot hand for holding the substrate 10 and the mask 220 is attached to an articulated arm. Each chamber such as the film forming chamber 110, the mask stock chamber 120, the transfer chamber 130, the buffer chamber 160, and the swirl chamber 170 maintains a high vacuum state during the manufacturing process of the organic EL display panel.

The film forming cluster 1 includes a pass chamber 150 for transferring the substrate 10 flowing from the upstream side in the substrate transfer direction to the transfer chamber 130, and a pass chamber 150 for transferring the substrate 10 having completed the film forming process to another film forming cluster on the downstream side. A buffer chamber 160 is included for. When the transfer robot 140 in the transfer chamber 130 receives the substrate 10 from the pass chamber 150 , it transfers it to one of the film formation chambers 110 . The transfer robot 140 also receives the substrate 10 on which film formation processing has been completed from the film formation chamber 110 and transfers it to the buffer chamber 160 . In the illustrated example, a swirl chamber 170 for changing the direction of the substrate 10 is provided further upstream of the pass chamber 150 and further downstream of the buffer chamber 160 .

(Deposition device)
FIG. 2 is a cross-sectional view schematically showing the configuration of the film forming apparatus. Each of the plurality of film formation chambers 110 is provided with a film formation apparatus 108 (also referred to as a vapor deposition apparatus). transfer of the substrate 10 to and from the transport robot 140, detection of substrate marks provided on the substrate 10, detection of mask marks provided on the mask 220, adjustment of the relative positions of the substrate 10 and the mask 220 (alignment), and alignment on the mask. A series of film formation processes such as fixing of the substrate 10 and film formation (evaporation) are performed by each component of the film formation apparatus.

In the following description, an XYZ orthogonal coordinate system with the vertical direction as the Z direction is used. In the XYZ orthogonal coordinate system, when the substrate is fixed so as to be parallel to the horizontal plane (XY plane) during film formation, the short side direction (direction parallel to the short side) of the rectangular substrate 10 having long sides and short sides is Let the X direction and the longitudinal direction (the direction parallel to the long side) be the Y direction. Also, the angle of rotation about the Z-axis is represented by θ.

The film forming apparatus 108 has a vacuum chamber 200 . The inside of the vacuum chamber 200 is maintained in a vacuum atmosphere or an inert gas atmosphere such as nitrogen gas. A substrate support unit 210 , a mask 220 , a mask table 221 , a cooling plate 230 and an evaporation source 240 are provided inside the vacuum chamber 200 .

The substrate support unit 210 is substrate support means having a function as a holder that supports the substrate 10 received from the transfer robot 140 . The mask 220 is, for example, a metal mask and has an opening pattern corresponding to the thin film pattern formed on the substrate. The mask 220 is placed on a frame-shaped mask table 221 which is a mask support unit, and film formation is performed after the substrate 10 is positioned and held on the mask. The substrate support unit 210 is composed of, for example, a support frame provided with a plurality of supports for supporting the periphery of the substrate 10 by placing or sandwiching it.

The cooling plate 230 is a plate-shaped member that contacts the surface of the substrate 10 opposite to the surface in contact with the mask 220 during film formation, and suppresses the temperature rise of the substrate 10 during film formation. The cooling plate 230 is the substrate 1
By cooling 0, alteration and deterioration of the organic material are suppressed. The cooling plate 230 may also serve as a magnet plate. The magnet plate is a member that enhances the adhesion between the substrate 10 and the mask 220 during film formation by attracting the mask 220 with a magnetic force. In order to improve the adhesion between the substrate 10 and the mask 220, the substrate support unit 210 may hold both the substrate 10 and the mask 220 and bring them into close contact with each other by an actuator or the like.

The evaporation source 240 is film forming means including a container (crucible) containing an evaporation material, a heater, a shutter, a driving mechanism, an evaporation rate monitor, and the like. Note that the film formation source is not limited to the evaporation source 240 . For example, the film forming apparatus 108 may be a sputtering apparatus using a sputtering target as a film forming source.

The control unit 270 controls the operation of each actuator of the actuator unit 282, the imaging control and image data analysis of the camera 261, the carrying-in/out control and alignment control of the substrate 10 and the mask 220, the film-forming source control, the film-forming control, and others. Perform various controls. The control unit 270 can be configured by, for example, a computer having a processor, storage means such as memory, storage, I/O, and the like. In this case, the functions of the control unit 270 are implemented by the processor executing a program stored in the memory or storage. As the computer, a general-purpose personal computer may be used, or a built-in computer or PLC (programmable logic controller) may be used. Alternatively, part or all of the functions of the control unit 270 may be configured with a circuit such as ASIC or FPGA. Note that the control unit 270 may be provided for each film forming apparatus, or one control unit 270 may control a plurality of film forming apparatuses.

(Configuration for mark detection)
A camera 261 is provided at the upper outer portion of the vacuum chamber 200 as a photographing means for performing optical imaging to generate image data. Camera 261 takes an image through a window (not shown) provided in vacuum chamber 200 . Although the present embodiment employs a one-step alignment method, a two-step alignment method may be used. In that case, a low-resolution wide-field first alignment camera (rough alignment) and a narrow-field high-resolution second alignment camera (fine alignment) are installed, and from the rough alignment Alignment is performed in the order of fine alignment.

The camera 261 in this embodiment is installed at a position where the corners of the substrate 10 and the mask 220 can be imaged. The imaging area of the camera 261 includes the substrate marks 104 on the substrate surface and the mask marks 224 on the mask surface. In this embodiment, four cameras 261 are provided so as to correspond to the four corners of the substrate 10 and mask 220 . However, the number and installation locations of alignment marks and the number, installation locations and types of cameras are not limited to this.

The control unit 270 analyzes image data (captured image) captured by the camera 261 and acquires position information of the board mark 104 and the mask mark 224 . For example, regarding the board mark 104 , image data acquired by imaging the imaging area 264 is analyzed by pattern matching processing to extract a shape that matches the model board mark 174 .

Since the position of the camera 261 is fixed, any position in the image data captured within the imaging area 264 can be converted into coordinate values. Therefore, the positions of the alignment marks detected from each captured image can be obtained as coordinate values.
As a result, the distance and angle between the substrate mark 104 and the mask mark 224 can be calculated. The camera 261 is a mark detection device that acquires position information of each alignment mark. Also, the camera 261 and the control unit 270 may be combined to form a mark detection device. The control unit 270 functions as detection means of the present invention.

In this embodiment, the substrate marks are formed on the substrate by laser machining and each mask alignment mark is formed on the mask by machining. However, the method of forming the mark is not limited to these, and can be selected according to the material and purpose.

(configuration for alignment)
A substrate Z actuator 250 , a clamp Z actuator 251 , and a cooling plate Z actuator 252 are provided on the outer upper portion of the vacuum chamber 200 . Each actuator is composed of, for example, a motor and a ball screw, or a motor and a linear guide. An alignment stage 280 is further provided on the outer upper portion of the vacuum chamber 200 .
The substrate Z actuator 250 is driving means for raising and lowering the entire substrate support unit 210 in the Z-axis direction. The substrate Z actuator 250 can be said to be a vertical movement means provided by the alignment means. The clamp Z actuator 251 is driving means for opening and closing the clamping mechanism of the substrate support unit 210 . The cooling plate Z actuator 252 is driving means for raising and lowering the cooling plate 230 .

The alignment stage 280 is an alignment device that moves the substrate 10 in the XY directions and rotates it in the θ direction to change the position with respect to the mask 220 . The alignment stage 280 can be said to be an in-plane moving means provided in the alignment means. The alignment stage 280 includes a chamber fixing portion 281 connected and fixed to the vacuum chamber 200 , an actuator portion 282 for performing XYθ movement, and a connecting portion 283 connected to the substrate support unit 210 . Note that the alignment stage 280 and the substrate support unit 210 may be combined to form an alignment device. Further, the alignment stage 280 and the substrate support unit 210 may be combined with the controller 270 to form an alignment apparatus.

As the actuator section 282, an actuator in which an X actuator, a Y actuator and a θ actuator are stacked may be used. Alternatively, a UVW type actuator in which a plurality of actuators cooperate may be used. Whichever type of actuator unit 282 is used, the actuator unit 282 is driven according to the control signal transmitted from the control unit 270 to linearly move the substrate 10 in the X and Y directions and rotationally move it in the θ direction. The control signal indicates the operation amount of each XY[theta] actuator in the case of a stacking type actuator, and indicates the operation amount of each UVW actuator in the case of a UVW type actuator.

The alignment stage 280 moves the substrate support unit 210 by XYθ. Although the position of the substrate 10 is adjusted in this embodiment, the position of the mask 220 may be adjusted, or the positions of both the substrate 10 and the mask 220 may be adjusted.

The control unit 270 performs various calculations based on image data. During normal alignment, the amount of movement of the substrate in the XYθ direction is calculated based on the amount of positional deviation between the substrate mark 104 and the mask mark 224 detected by the mark detection device. Subsequently, the control unit 270 converts the calculated amount of movement of the substrate or the like into a driving amount of a stepping motor, a servo motor, or the like provided for each actuator of the alignment stage 280, and generates a control signal. In addition, if necessary, a sensor signal is received from the alignment stage 280 to perform feedback control.

(processing flow)
The flow of processing will be described with reference to the drawings. FIG. 5 is a flowchart showing mark detection processing and subsequent steps in this embodiment.

FIG. 6 is a plan view showing board marks and model board marks used in this flow. The substrate mark 104 shown in FIG. 6(a) is actually formed on the substrate 10, and is shown in FIG.
It is the same as a). In the cross-shaped substrate mark 104 in which two lines (a vertical line and a horizontal line) intersect, the vertical line and the horizontal line each have the thickness of the first region 104t and the thickness of the second region 104m due to the characteristics of laser processing. (the thickness of the second region 104m is substantially constant). Here, the length of the vertical line of the board mark 104 is h1, the length of the horizontal line is w1, the length of the second area 104m of the vertical line is h2, and the length of the second area 104m of the horizontal line is w2.

On the other hand, the cross shape where the vertical line model and the horizontal line model intersect shown by solid lines in FIG. short), modified model board mark 176 . As with the second region 104m, the corrected model substrate mark 176 has a vertical line model length h2 and a horizontal line model length w2. In other words, the corrected model board mark 176 is a linear image having a length corresponding to the second region of the board mark 104 . The thickness (width) of the vertical lines and horizontal lines is the same as the thickness of the second region 104m. In this embodiment, modified model board mark 176 replaces model board mark 174 and is used as the model image.

In this flow, the mask 220 is carried into the film formation chamber 110 from the mask stock chamber 120 and supported by the mask table 221 , and the substrate 10 is carried into the film formation chamber 110 from the pass chamber 150 and supported by the substrate support unit 210 . start from the

In step S<b>101 , the substrate support unit 210 moves the substrate 10 in the vertical direction, and the distance between the substrate 10 and the mask 220 in the Z direction is set within the focus range of the camera 261 . be an alignment distance that includes In this embodiment, the substrate 10 is moved in the XY[theta] directions within the XY plane while maintaining the alignment distance between the substrate 10 and the mask 220. FIG.
In step S102, the camera 261 images the imaging area 264 to generate image data.

In step S<b>103 , the control unit 270 analyzes the image data and detects the board mark 104 . Here, a pattern matching method is used as an alignment mark recognition method. The pattern matching method is a method of recognizing an alignment mark by determining the correlation between the pattern shape of a model mark stored in advance in the memory of the control unit 270 and the shape of the alignment mark in the image. Note that the method is not limited to this as long as the mark can be identified, and for example, an edge detection method or the like may be used.

Here, a characteristic method in this flow will be described. As described above, when the first region 104t of the board mark 104 is swollen (the thickness of the line in the first region is larger than the thickness of the line in the second region other than the vicinity of the end) case), if image processing is performed using the model board mark 174 having the same size as the board mark 104, the recognition accuracy will be degraded. Therefore, in the corrected model board mark 176 of FIG. 6B, the overall size is approximately the same as the second region 104m of the board mark 104. In FIG. Therefore, over the entire modified model board mark 176 , the tip thickness matches the actual board mark 104 . In other words, the control unit 270 in this flow tries to extract a graphic having a high degree of correlation with the modified model board mark 176 from the imaging area 264 . As a result, detection of the second area 104m becomes possible.

The control unit 270 generates data in which the area 178 deleted from the model board mark 174 is added to the detected second area 104m, and stores the data in the memory as the position information of the board mark 104. FIG. However, the control section 270 may use the second area 104m as it is as the board mark. In that case, mark comparison is performed on the premise of the size and position of the second area 104m in the determination processing described later.

In step S104, the control unit 270 detects the mask mark 224 from the image data and stores the position information in the memory. Any method such as a pattern matching method or an edge detection method can be employed here as well.

In step S105, the control unit 270 compares the coordinate information of the board mark 104 and the coordinate information of the mask mark 224 stored in the memory. Then, if the condition that the positional relationship such as the distance and angle between the two is within a predetermined allowable range is satisfied, it is determined that the alignment is completed. On the other hand, if the positional relationship is out of the allowable range, the process proceeds to step S106, and the substrate 10 is moved within the plane in the XY[theta] directions based on the amount of deviation from the ideal positional relationship. By repeating this process, the relationship between the substrate 10 and the mask 220 falls within a predetermined range.

At step S107, the substrate support unit 210 operates to bring the substrate 10 and the mask 220 into contact. For example, substrate Z actuator 250 lowers substrate 10 onto mask 220 .

In step S<b>108 , the evaporation source 240 as a film forming source is heated, and the film forming material is formed on the substrate 10 through the mask 220 . Thereby, a film having a shape corresponding to the mask pattern is formed on the substrate. The above flow completes the film forming process inside the chamber.

As described above, in this embodiment, when detecting a substrate mark whose end portion is swollen or deformed due to the characteristics of laser processing, an area that is slightly smaller than the substrate mark and corresponds to the deformed portion of the substrate mark is deleted. Use modified model board marks. As a result, since the detection process can be performed without being affected by the deformed portion of the substrate mark, the accuracy of mark detection is improved, and good alignment becomes possible.

<Example 2>
In this embodiment, an example in which each alignment mark shape used for the substrate 10 is different from that in the first embodiment will be described.

FIG. 7A shows a board mark 104 according to this embodiment. As described above, due to the influence of laser processing, the first area 104t of one linear substrate mark 104 has a bulging shape compared to the second area 104m.
FIG. 7(b) shows a model board mark 174 used when detecting the board mark 104 of this embodiment by a conventional method. If the length (h1) of the model board mark 174 is made to match the length of the board mark 104 in this way, the detection accuracy of the board mark 104 by the pattern matching method may be lowered due to the presence of the first region 104t. be.

Therefore, in this embodiment, detection is performed using a modified model substrate mark 176 as shown in FIG. 7(c). Since the length h2 of one linear modified model board mark 176 matches the length of the second area 104m whose thickness is within a certain range, there is little risk of deterioration in detection accuracy.

<Example 3>
Next, an example in which the modified model board mark 176 is created and applied is different will be described. This embodiment is characterized in that a plurality of types of corrected model board marks 176 are created and an appropriate one is selected and used according to the board mark 104 .

FIGS. 8(a) and 8(b) are modified model board marks 176 each having a different width (horizontal line model length) and height (vertical line model length) than FIG. 6(b). be. Here, the degree of bulging or deformation of the first region 104t of the substrate mark 104 may vary slightly depending on the material of the substrate 10, accuracy of laser processing, and the like. Therefore, the corrected model board mark 176 shown in FIG. 6B may overlap the bulging portion. Conversely, if the modified model board mark 176 shown in FIG. 6B is too small compared to the second area 104m, the accuracy of mark detection may decrease.

Therefore, the control unit 270 of this embodiment, in addition to the mark shown in FIG. ) and the one shown in FIG. 8B in which the length of the vertical line model and the horizontal line model are shorter than the corrected model board mark 176 in FIG. A mark 176 is prepared and stored in memory. Then, the board mark 104 in the captured image is compared with each of the plurality of corrected model board marks 176, and the most appropriate size for comparison with the mark with the bulge removed in the first region 104t is selected. As a result, deterioration in mark detection accuracy can be prevented. It should be noted that which modified model board mark 176 to select when detecting the mark may be selected manually by the user looking at the captured image, or may be selected by the control unit 270 appropriately.

In this embodiment, the length of the vertical line model and the length of the horizontal line model of the modified model substrate mark 176 are matched, but the present invention is not limited to this. For example, if the degree of deformation of the edge of the board mark tends to be different for each edge, the length of the vertical line model and the horizontal line model of the corrected model board mark and the intersection position of the vertical line model and the horizontal line model are changed accordingly. may
Also, when using a board mark having a shape other than a cross, for example, a single linear board mark, a plurality of types of modified model board marks having different sizes may be prepared as described in the present embodiment.

<Example 4>
In this embodiment, another example of the method for creating the modified model board mark 176 will be described.
In each of the embodiments described above, the size and shape of the modified model board mark 176 are determined based on the design values of the board mark 104 . However, based on the image data of the circuit board mark 104 captured by the camera 261 as a photographing means, the control unit 270 deletes the bulge and deformed portion from the circuit board mark 104 to create a corrected model circuit board mark 176. may
According to this embodiment, if the boundary between the substrate mark 104 acquired by imaging and the surroundings (background) is not clear, it may not be possible to create a model image as precise as the above embodiments. Mark detection and alignment can be performed based on the marks 104 .

261: camera, 270: control unit

Claims (20)

A mark detection device for detecting an alignment mark,
a photographing means for obtaining a photographed image by photographing an area including the alignment mark;
detection means for comparing the photographed image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
The detection means compares a portion of the alignment mark excluding an end portion of the linear portion with the model image.
A mark detection device characterized by: In the alignment mark, the thickness of the end of the linear portion is larger than the thickness of the portion other than the end of the linear portion.
2. The mark detection device according to claim 1, wherein: the linear portion of the alignment mark includes a first linear portion and a second linear portion intersecting the first linear portion;
The detection means compares a portion of the alignment mark excluding both ends of the first linear portion and both ends of the second linear portion with the model image.
3. The mark detection device according to claim 1, wherein: the model image includes a linear model portion corresponding to the linear portion of the alignment mark;
The detection means selects the model image used for comparison from a plurality of patterns having different lengths of the linear model portions.
4. The mark detection device according to any one of claims 1 to 3, characterized in that: The alignment mark is a substrate mark formed on the substrate by laser processing.
5. The mark detection device according to any one of claims 1 to 4, characterized in that: the substrate is a silicon wafer substrate
6. The mark detection device according to claim 5, wherein: The model image is generated based on the design value of the alignment mark or the alignment mark included in the captured image.
7. The mark detection device according to any one of claims 1 to 6, characterized in that: A mark detection device for detecting an alignment mark,
a photographing means for obtaining a photographed image by photographing an area including the alignment mark;
detection means for comparing the photographed image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
the model image includes a linear model portion corresponding to the linear portion of the alignment mark;
The length of the linear model portion of the model image is shorter than the length of the linear portion of the alignment mark.
A mark detection device characterized by: In the alignment mark, the thickness of the end of the linear portion is larger than the thickness of the portion other than the end of the linear portion.
9. The mark detection device according to claim 8, wherein: The length of the linear model portion of the model image is a length corresponding to the other partial length of the linear portion of the alignment mark.
10. The mark detection device according to claim 9, characterized in that: the linear portion of the alignment mark includes a first linear portion and a second linear portion intersecting the first linear portion;
the linear model portion of the model image includes a first linear model portion and a second linear model portion intersecting the first linear model portion;
the length of the first linear model portion of the model image is shorter than the length of the first linear portion of the alignment mark;
The length of the second linear model portion of the model image is shorter than the length of the second linear portion of the alignment mark.
The mark detection device according to any one of claims 8 to 10, characterized in that: The detection means selects the model image used for comparison from among a plurality of patterns having different lengths of the linear model portions.
12. The mark detection device according to any one of claims 8 to 11, characterized in that: The alignment mark is a substrate mark formed on the substrate by laser processing.
13. The mark detection device according to any one of claims 8 to 12, characterized in that: the substrate is a silicon wafer substrate
14. The mark detection device according to claim 13, characterized in that: The model image is generated based on the design value of the alignment mark or the alignment mark included in the captured image.
15. The mark detection device according to any one of claims 8 to 14, characterized in that: a mark detection device according to any one of claims 1 to 15;
and alignment means for aligning the substrate and the mask based on the positions of the alignment marks.
An alignment device characterized by: an alignment device according to claim 16;
an evaporation source device that forms a film on the substrate through the mask that is aligned with the substrate.
A film forming apparatus characterized by: A mark detection method for detecting an alignment mark, comprising:
a photographing step of obtaining a photographed image by photographing an area including the alignment mark;
a detection step of comparing the captured image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
The detection step includes a comparison step of comparing a portion of the alignment mark excluding an end portion of the linear portion with the model image.
A mark detection method characterized by: A mark detection method for detecting an alignment mark, comprising:
a photographing step of obtaining a photographed image by photographing an area including the alignment mark;
a detection step of comparing the captured image and the model image to detect the position of the alignment mark;
the alignment mark includes a linear portion;
the model image includes a linear model portion corresponding to the linear portion of the alignment mark;
The length of the linear model portion of the model image is shorter than the length of the linear portion of the alignment mark.
A mark detection method characterized by: detecting the alignment mark by the mark detection method according to claim 18 or 19;
an alignment step of aligning the substrate and the mask based on the positions of the alignment marks;
and a film forming step of forming a film on the substrate through the mask aligned with the substrate.
A film forming method characterized by:

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