JP2022114519A - Illumination device, illumination method and substrate inspection device - Google Patents

Abstract

To provide an illumination technology that is suitable for photographing by an imaging unit a peripheral part of a substrate having a notch part and non-notch part.SOLUTION: The illumination device comprises: a first illumination unit that is arranged on a side opposite a rotation center of a substrate with respect to an imaging area where the substrate is photographed by an imaging unit, and when a non-notch part is located in the imaging area, irradiates the imaging area with first illumination light; a second illumination unit that, when a notch part is located in the imaging area, irradiates the imaging area with second illumination light orthogonal to a surface normal line of the substrate in the imaging area and having a second irradiation direction different from a first irradiation direction of the first illumination light; and a third illumination unit that when the notch part is located in the imaging area, irradiates the imaging area with third illumination light orthogonal the surface normal line thereof and having a third irradiation direction different from both the first irradiation direction and second irradiation direction.SELECTED DRAWING: Figure 3B

Description

The present invention provides an illumination technology suitable for capturing an image of a peripheral portion of a substrate such as a semiconductor wafer provided with a cutout portion such as a notch or an orientation flat at the peripheral portion thereof, and an image captured using the illumination technology. The present invention relates to a substrate inspecting apparatus for inspecting a substrate based on an image obtained from a printed circuit board.

In order to inspect the peripheral edge of a substrate such as a semiconductor wafer, for example, in the apparatus described in Patent Document 1, an image of the peripheral edge is acquired by an imaging unit while illuminating the peripheral edge of the substrate using a hemispherical illumination device. there is In this specification, a region of the peripheral portion of the substrate where the cutout portion is not provided is referred to as a “non-cutout portion”.

JP 2016-178298 A

In the above-described conventional apparatus, when an image of the periphery is captured by the imaging unit, it is not distinguished whether the cutout portion or the non-cutout portion is located in the imaging area of the imaging unit, and the periphery of the substrate is captured in a single illumination mode. Lighting. Here, when only the non-notch portion is to be inspected, the peripheral portion of the substrate may be imaged in an illumination mode suitable for photographing the non-notch portion. However, in the case of inspecting notches as well, it is difficult to photograph the notches appropriately in the illumination mode, and there is a problem that the accuracy of inspecting the notches is lowered. In other words, the conventional apparatus has a problem that it is difficult to satisfactorily photograph the notched portion and the non-notched portion having different external shapes.

The present invention has been made in view of the above problems, and provides an illumination technique suitable for capturing an image of a peripheral edge portion of a substrate having a notched portion and a non-notched portion by an imaging section, and uses the illumination technique. It is an object of the present invention to provide a board inspection technique capable of inspecting the periphery of a board with high accuracy.

According to a first aspect of the present invention, a notch portion provided in a part of the peripheral portion of a substrate rotated around a rotation axis and a non-notched portion of the peripheral portion excluding the notch portion are imaged by an imaging unit. The illumination device used is arranged on the opposite side of the rotation center of the substrate with respect to the imaging area where the substrate is imaged by the imaging unit, and when the non-notched portion is positioned in the imaging area, the first illumination light is applied to the imaging area. and a second irradiation direction orthogonal to the surface normal of the substrate in the imaging region and different from the first irradiation direction of the first illumination light when the notch is positioned in the imaging region. , a second illumination unit that irradiates the imaging region with the second illumination light; and a third illumination unit that is perpendicular to the surface normal and different from both the first irradiation direction and the second irradiation direction when the notch is positioned in the imaging region. and a third illumination unit that irradiates the imaging area with third illumination light having an illumination direction.

A second aspect of the present invention provides an imaging unit for capturing an image of a notch provided in a part of the peripheral edge of a substrate rotated about a rotation axis and a non-notched portion of the peripheral edge excluding the notch. The illumination method used includes: (a) a step of irradiating the imaging region with the first illumination light from the opposite side of the rotation center of the substrate with respect to the imaging region where the substrate is imaged by the imaging unit; (c) irradiating the second illumination light in a second irradiation direction orthogonal to the surface normal of the substrate and different from the first irradiation direction of the first illumination light; irradiating the third illumination light in a third irradiation direction different from both of the second irradiation directions, and executing the step (a) when the non-notched portion is positioned in the imaging region in which the substrate is imaged by the imaging unit. and at least one of step (b) and step (c) is performed when the notch portion is positioned in the imaging region.

A third aspect of the present invention is a substrate inspection apparatus for inspecting a substrate having a notch formed in a part of the peripheral edge thereof, comprising: a substrate holding unit for holding the substrate and rotating the substrate around a rotation axis; an imaging unit that captures an image of the peripheral edge of the substrate rotated by the holding unit to obtain a notch image of the notch and a non-notch image of the non-notch portion of the peripheral edge excluding the notch; and an inspection unit that inspects the peripheral edge of the substrate based on the notch image and the non-notch image acquired by the imaging unit while being illuminated by the illumination device.

In the invention configured as described above, the imaging region is illuminated by the first illumination light when the notch is not positioned (the non-notch is positioned). On the other hand, when the notch is positioned, the imaging region is illuminated with at least one of the second illumination light and the third illumination light.

According to the invention configured as described above, when the peripheral portion of the substrate is imaged by the imaging section, the illumination pattern of the imaging area can be switched according to whether or not the notch is positioned in the imaging area. Therefore, illumination suitable for imaging the periphery of the substrate by the imaging unit can be obtained. In addition, by using the illumination technique, the periphery of the substrate can be imaged satisfactorily. As a result, the peripheral portion of the substrate can be inspected with high accuracy.

1 is a diagram showing a substrate processing system equipped with an embodiment of a substrate inspection apparatus according to the present invention; FIG. It is a side view which shows the structure of a board|substrate inspection apparatus. 4 is a perspective view schematically showing the configuration and operation of an imaging unit and an illumination unit; FIG. 4 is a perspective view schematically showing the configuration and operation of an imaging unit and an illumination unit; FIG. 4 is a perspective view schematically showing the configuration and operation of an imaging unit and an illumination unit; FIG. 3 is a flow chart showing the operation of the substrate inspection apparatus shown in FIG. 2; FIG. 2 shows a second embodiment of a lighting device according to the invention; It is a figure which shows 3rd Embodiment of the illuminating device which concerns on this invention.

FIG. 1 is a diagram showing a substrate processing system equipped with an embodiment of a substrate inspection apparatus according to the present invention. The substrate processing system 100 processes a substrate W having a notch formed in a portion of the peripheral portion thereof. The substrate processing system 100 includes a substrate processing section 110 that processes substrates W, and an indexer section 120 coupled to the substrate processing section 110 . The indexer unit 120 includes a container C for containing the substrates W (FOUP (Front Opening Unified Pod) containing a plurality of substrates W in a sealed state, SMIF (Standard Mechanical
Interface) pods, OCs (Open Cassettes), etc.) and the container C held by the container holding unit 121 are accessed, and unprocessed substrates W are transferred from the container C. An indexer robot 122 for picking up and storing processed substrates W in containers C is provided. Each container C accommodates a plurality of substrates W in a substantially horizontal posture.

The indexer robot 122 includes a base portion 122a fixed to an apparatus housing, an articulated arm 122b provided rotatably about a vertical axis with respect to the base portion 122a, and a hand attached to the tip of the articulated arm 122b. 122c. The hand 122c has a structure in which the substrate W can be placed and held on its upper surface. Since an indexer robot having such articulated arms and hands for holding substrates is well known, a detailed description thereof will be omitted.

The substrate processing section 110 includes a substrate transfer robot 111 arranged substantially in the center in plan view, and a plurality of processing units 1 arranged so as to surround the substrate transfer robot 111 . Specifically, a plurality of processing units 1 are arranged facing the space in which the substrate transport robot 111 is arranged. The substrate transport robot 111 randomly accesses these processing units 1 to transfer the substrate W thereon. On the other hand, each processing unit 1 performs a predetermined process on the substrate W. FIG. In this embodiment, one of these processing units 1 corresponds to the board inspection apparatus 10 according to the present invention, and is equipped with the first embodiment of the lighting apparatus according to the present invention.

FIG. 2 is a side view showing the configuration of the board inspection apparatus. The substrate inspection apparatus 10 is a single substrate type apparatus that inspects substrates W one by one. The substrate inspection apparatus 10 inspects the surface condition of the peripheral portion We of the substrate W. As shown in FIG. For the convenience of the following description, each drawing shows an XYZ orthogonal coordinate axis in which the direction orthogonal to the vertical direction Z and the imaging direction X for the inspection is defined as the "Y direction".

In the substrate inspection apparatus 10 , a substrate holding portion 12 is provided inside a housing 11 . The substrate holding unit 12 includes a stage 12a that holds the substrate W transferred into the housing 11 by the substrate transfer robot 111, and a stage rotation mechanism 12b that rotates the stage 12a around a rotation axis AX extending in the vertical direction Z. have. The stage 12a has a substantially disk-shaped outer shape. A plurality of suction holes (not shown) are dispersedly provided on the upper surface of the stage 12a. These suction holes are connected to a vacuum pump or the like. By operating the vacuum pump, the atmosphere in the suction holes is exhausted. Thereby, the stage 12a holds the substrate W placed on the upper surface of the stage 12a in a horizontal posture. The holding of the substrate W is not limited to the suction method described above, and may be a mechanical chuck method for holding the substrate W mechanically. The stage rotation mechanism 12b has a rotation shaft 12b1 extending vertically downward from the center lower surface of the stage 12a, and a motor 12b2 connected to the lower end of the rotation shaft 12b1. Then, the stage 12a and the substrate W held on the stage 12a are rotated about the rotation axis AX parallel to the vertical direction Z by the operation of the motor 12b2.

Further, inside the housing 11 , the observation unit 15 containing the imaging section 13 and the illumination device 14 moves in the horizontal direction X, thereby approaching and separating from the substrate holding section 12 . More specifically, when the substrate transport robot 111 loads and unloads the substrate W onto and from the stage 12a, the observation unit 15 is moved in the (-X) direction. Thereby, the observation unit 15 is separated from the stage 12a. On the other hand, when inspecting the board, the observation unit 15 is moved in the (+X) direction. As a result, the observation unit 15 is brought close to the stage 12a until a notch detector 144, which will be described later, faces the peripheral edge We of the substrate W held on the stage 12a, as shown in FIG.

3A to 3C are perspective views schematically showing the configuration and operation of the imaging section and the illumination section. The imaging unit 13 is arranged apart from the stage 12a in the X direction. For example, a CCD camera or the like is used as the imaging unit 13 . The image capturing unit 13 captures an image of a portion of the peripheral edge We of the substrate W held on the stage 12a, which is located in the image capturing area IA, particularly the end face. The image of the end surface is converted into an electrical signal and output to the control unit 16 that controls the board inspection apparatus 10 as a whole. Thus, the image of the imaging area IA is acquired by the imaging unit 13 .

In this embodiment, three types of illumination units 141 to 143 are provided as the illumination device 14 for illuminating the imaging area IA so that the imaging unit 13 can take an image satisfactorily. The lighting section 141 is composed of two bar lighting members 141a and 141b corresponding to an example of the "first bar lighting member" of the present invention. Each of the bar illumination members 141a and 141b has a light emitting surface extending in a direction Y perpendicular to both the axial direction Z of the rotation axis AX and the imaging direction X in a bar shape. The bar illumination members 141a and 141b are arranged so as to sandwich the imaging unit 13 in the Y direction. When the bar illumination members 141a and 141b are turned on in response to a command from the control unit 16, the first illumination light L1 is emitted in a first irradiation direction D1 substantially parallel to the imaging direction X as shown in FIG. 3A. The imaging area IA is illuminated. In this specification, the illumination of the imaging area IA by only the illumination unit 141 is referred to as a “first illumination pattern”. Also, in order to schematically clarify the range illuminated by the illumination light, the range is marked with dots in FIGS. 3A to 3C (and FIGS. 5 and 6 described later).

The lighting section 142 is composed of one bar lighting member having the same configuration as the bar lighting members 141a and 141b. The illumination unit (second bar illumination member) 142 is arranged upstream of the bar illumination member 141a in the rotation direction R of the substrate W, with its light emitting surface facing the imaging area IA. Therefore, when the illumination unit 142 is turned on in response to a command from the control unit 16, the second illumination light L2 is emitted in the second irradiation direction D2 from the upstream side in the rotation direction R as shown in FIG. This illuminates the imaging area IA. In this specification, the illumination of the imaging area IA by only the illumination unit 142 is referred to as a “second illumination pattern”.

The lighting unit 143 is configured by one bar lighting member having the same configuration as the bar lighting members 141a and 141b. The illumination unit (third bar illumination member) 143 is arranged downstream of the bar illumination member 141b in the rotation direction R of the substrate W, with its light emitting surface facing the imaging area IA. Therefore, when the illumination unit 143 is turned on in response to a command from the control unit 16, as shown in FIG. This illuminates the imaging area IA. In this specification, the illumination of the imaging area IA by only the illumination unit 143 is referred to as a “third illumination pattern”. In order to clearly distinguish between the illumination units 141 to 143, the illumination units 141 to 143 will be referred to as the "central illumination unit 141," the "upstream illumination unit 142," and the "downstream illumination unit 143," respectively. called.

The illumination device 14 also has a notch detector 144 that detects the notch Wn of the substrate W in order to optimize the switching timing of lighting and extinguishing of the illumination units 141 to 143 . The notch detector 144 has a light projector 144a arranged at a position higher than the substrate W held on the stage 12a and a light receiver 144b arranged at a position lower than the substrate W. Then, as shown in FIG. 2, when the observation unit 15 is moved closer to the stage 12a, the light projector 144a and the light receiver 144b move toward the periphery of the substrate W near the upstream side of the imaging area IA in the rotation direction R of the substrate W. They are arranged so as to sandwich the portion We from above and below. Therefore, the notch portion Wn of the substrate W is detected at a position Ps between the light emitter 144a and the light receiver 144b (hereinafter referred to as "notch detection position"). That is, the notch detector 144 has a function of notifying that the rotation angle of the substrate W has reached a predetermined angle. For example, as shown in FIGS. 3B and 3C, while the portion other than the notch Wn of the peripheral portion We of the substrate W, that is, the non-notch Wnn is positioned, the light emitted from the light projector 144a is emitted from the non-notch Wnn. is shaded by On the other hand, as shown in FIG. 3A, for example, when the notch Wn of the substrate W is positioned at the notch detection position Ps, the light emitted from the light projector 144a passes through the notch Wn and reaches the light receiver 144b. By receiving the light, the light receiver 144b detects the notch Wn and notifies the control unit 16 of it. Therefore, the control unit 16 can accurately obtain the rotation angle of the substrate W based on the notch detection position Ps, and can accurately calculate the position of the notch Wn in the rotation direction R. Then, the control unit 16 switches the illumination pattern based on the rotation angle.

As shown in FIG. 2 , the control unit 16 is arranged outside the housing 11 , and controls each unit of the substrate inspection apparatus 10 to switch the illumination pattern and to obtain an image captured by the imaging unit 13 . Based on this, the peripheral portion We of the substrate W, particularly the end face, is inspected. More specifically, the control unit 16 is a general circuit in which a calculation unit 161 (for example, a CPU) that performs various calculation processes and a storage unit 162 (for example, a ROM or a RAM) that stores a basic program and various information are connected to a bus line. It is a typical computer system configuration. The bus line further includes a fixed disk 163 (for example, a hard disk drive) for storing inspection programs, a display unit 164 (for example, a display) for displaying various information, and an input unit 165 (for example, a (keyboard, mouse, etc.), and a communication unit 166 that communicates with the substrate holding unit 12, the imaging unit 13, and the lighting device 14 are appropriately connected via an interface (I/F) or the like. For example, a touch panel display in which the functions of the display unit 164 and the input unit 165 are integrated may be used.

In the control unit 16, an inspection program stored in the fixed disk 163 in advance is copied to the storage unit 162 (for example, RAM), and the calculation unit 161 executes calculation processing according to the inspection program in the storage unit 162. Illumination pattern switching and substrate W inspection are performed. Thus, the calculation unit 161 of the control unit 16 functions as the "switching control unit" and the "inspection unit" of the present invention, controls each unit of the device, and executes the operations described below.

FIG. 4 is a flow chart showing the operation of the substrate inspection apparatus shown in FIG. When the substrate W needs to be inspected, the substrate transport robot 111 places the substrate W horizontally on the stage 12a. In response to this, the vacuum pump operates to hold the substrate W. As shown in FIG. Thus, loading of the substrate W is performed (step S1). At this time, the substrate inspection apparatus 10 is in an initial state. That is, the stage 12a stops rotating. Also, the observation unit 15 is separated from the stage 12a in the (-X) direction. Also, the lighting units 141 to 143 are all turned off.

After the loading is completed, the substrate transport robot 111 is withdrawn from the housing 11, the observation unit 15 is moved closer to the stage 12a (see FIG. 2), and the stage 12a is rotated by the stage rotation mechanism 12b. Rotation is started (step S2). After the substrate W starts rotating, the notch detector 144 detects the notch Wn before the substrate W makes one rotation about the rotation axis AX (“YES” in step S3). Then, the calculation unit 161 determines that the cutout portion Wn does not exist in the imaging area IA, in other words, determines that the non-cutout portion Wnn is positioned in the imaging area IA, and gives a lighting command to the central illumination unit 141 . Only the central illumination unit 141 that receives this lights up (step S4). Accordingly, as shown in FIG. 3A, the imaging area IA is illuminated only by the first illumination light L1 emitted in the first illumination direction D1 (first illumination pattern). Further, the imaging unit 13 images the non-notch portion Wnn under illumination with the first illumination pattern to obtain a non-notch portion image (step S5). This non-notch portion image is obtained and stored in the fixed disk 163 by rotating the substrate W by a predetermined rotation angle in the rotational direction R from the detection of the notch portion Wn, and the downstream notch portion Wnd of the notch portion Wn is imaged in step S6. Execution continues until it is determined that the area IA has been reached. Here, the “downstream notch portion Wnd” means a portion of the notch portion Wn located downstream in the rotation direction R, as shown in FIGS. 3B and 3C. In addition to the downstream cutout portion Wnd, the cutout portion Wn has an upstream cutout portion Wnu located on the upstream side in the rotation direction R. As shown in FIG.

In step S6, as shown in FIG. 3B, when the calculation unit 161 determines that the downstream notch Wnd has reached the imaging area IA, it gives a turn-off command to the central lighting unit 141 and gives a turn-on command to the upstream lighting unit 142. . As a result, the first illumination pattern is switched to the second illumination pattern, and only the upstream illumination section 142 is lit (step S7). Here, the main reason for pattern switching is that, for example, if an attempt is made to image the downstream notch portion Wnd with the first illumination pattern, vignetting or scattering of illumination light occurs at the downstream end portion of the notch portion Wn. It is difficult to uniformly illuminate the downstream notch portion Wnd under conditions such as vignetting. On the other hand, by switching to the second illumination pattern, only the second illumination light L2 emitted in the second illumination direction D2 from a position displaced upstream of the central illumination unit 141 in the rotation direction R can illuminate the imaging area IA. is illuminated. Therefore, the downstream notch Wnd is efficiently and uniformly irradiated with the second illumination light L2. As a result, the imaging unit 13 can image the notch Wn under illumination with the second illumination pattern, and obtain a good notch image mainly including the image of the downstream notch Wnd (step S8). This notch image acquisition and storage in the fixed disk 163 is continued until the upstream notch site Wnu of the notch Wn reaches the imaging area IA ("YES" is determined in step S9).

In step S9, as shown in FIG. 3C, when the calculation unit 161 determines that the upstream notch Wnu has reached the imaging area IA, it gives the upstream illumination unit 142 a turn-off command and the downstream illumination unit 143 a turn-on command. . Thereby, the illumination pattern is switched from the second illumination pattern to the third illumination pattern, and only the downstream illumination section 143 is lit (step S10). Here, the main reason for pattern switching is the same as in step S7 above. The imaging area IA is illuminated only by the third illumination light L3 that illuminates D3. As a result, the upstream notch Wnu is efficiently and uniformly irradiated with the third illumination light L3. As a result, the imaging unit 13 can image the notch Wn under illumination with the third illumination pattern, and obtain a good notch image mainly including the image of the upstream notch Wnu (step S11). This notch image acquisition and storage in fixed disk 163 are continued until notch Wn passes imaging area IA (“YES” is determined in step S12). By executing steps S8 and S11 in this manner, an image of the entire notch portion Wn can be obtained satisfactorily.

In step S12, when the calculation unit 161 determines that the notch Wn has passed through the imaging area IA, in other words, that the non-notch Wnn is located in the imaging area IA, the downstream lighting unit 143 is instructed to turn off. A lighting command is given to the central lighting unit 141 . As a result, the third illumination pattern is switched to the first illumination pattern, and only the central illumination section 141 is lit (step S13). As a result, similarly to step S5, the imaging unit 13 captures the non-notch portion Wnn under illumination with the first illumination pattern to obtain a non-notch portion image (step S14). Acquisition of the image of the non-notch portion and storage in the fixed disk 163 are performed when the notch detection unit 144 detects the notch Wn as a result of the substrate W rotating one round after the previous detection of the notch Wn by the notch detection unit 144 ( This is continued until "YES" in step S15). By executing steps S5 and S14 in this way, it is possible to satisfactorily acquire an image of the entire non-notch portion Wnn. Also, at this point, acquisition of the image for the entire circumference of the peripheral portion We of the substrate W is completed.

In response to the detection of the notch Wn for the second time ("YES" in step S15), the calculation unit 161 reads out the omnidirectional image of the peripheral edge We of the substrate W from the fixed disk 163 to the storage unit 162, and performs processing similar to the conventional technology. The peripheral edge portion We of the substrate W is inspected. In parallel with this, the calculation unit 161 gives a turn-off command to the central illumination unit 141 to stop the illumination of the imaging area IA (step S16). Further, the calculation unit 161 gives a rotation stop command to the stage rotation mechanism 12b to stop the rotation of the stage 12a (step S17). Subsequently, after the observation unit 15 is moved away from the stage 12a in the (−X) direction and the suction holding of the substrate W on the stage 12a is released, the hand (not shown) of the substrate transport robot 111 is moved to the housing 11. enter inside. Then, the substrate transport robot 111 unloads the substrate W (step S18).

As described above, in the present embodiment, the illumination pattern is switched and optimized in response to the sequential positioning of the non-notch portion Wnn, the downstream notch portion Wnd, and the upstream notch portion Wnu in the imaging area IA. Therefore, the imaging unit 13 can acquire an image suitable for inspection of the substrate W over the entire circumference of the peripheral portion We of the substrate W. Moreover, since the peripheral portion We of the substrate W is inspected based on such an image, inspection accuracy can be improved.

Further, each of the lighting units 141 to 143 is composed of a bar lighting member having a light emitting surface extending like a bar in a direction orthogonal to the axial direction Z of the rotation axis AX. Therefore, the illumination device 14 is compact in the axial direction Z. As shown in FIG.

In the above embodiment, the central illumination unit 141 arranged on the opposite side of the rotation center of the substrate W with respect to the imaging area IA, that is, on the (−X) direction side of the illumination units 141 to 143 is the “first illumination unit” of the present invention. It corresponds to an example of "part". Further, the upstream illumination unit 142 has a second irradiation direction D2 orthogonal to the surface normal N of the substrate W in the imaging area IA and different from the first irradiation direction D1. ” corresponds to an example. Further, the downstream illumination unit 143 has a third irradiation direction D3 that is orthogonal to the surface normal N of the substrate W in the imaging area IA and that is different from both the first irradiation direction D1 and the second irradiation direction D2, It corresponds to an example of the "third illumination section" of the present invention. Further, steps S5, S8, and S11 correspond to examples of "step (a)," "step (b)," and "step (c)" of the present invention, respectively.

By the way, in the first embodiment, both the lighting units 142 and 143 for illuminating the notch Wn are fixedly arranged. Therefore, the second irradiation direction D2 and the third irradiation direction D3 are also fixed. However, since the shape and size of the notch Wn may be changed according to the type and size of the substrate W, taking this point into consideration, as shown in FIG. The irradiation direction D3 may be configured to be changeable (second embodiment).

FIG. 5 is a diagram showing a second embodiment of the lighting device according to the present invention. The difference of the second embodiment from the first embodiment is that an adjusting mechanism 17 is connected to the lighting units 142 and 143 so as to be rotatable about a rotation axis RX extending in the vertical direction Z. , and other configurations are the same as those of the first embodiment. Therefore, the same reference numerals are given to the same configurations, and the description of the configurations is omitted.

In the second embodiment, the adjustment mechanism 17 rotates the illumination units 142 and 143 around the rotation axis RX according to the shape, size, etc. of the notch Wn to change the second irradiation direction D2 and the third irradiation direction D3. Individually adjustable. Therefore, various substrates W can be handled. The adjustment mechanism 17 may be configured to rotate the lighting units 142 and 143 in response to an operator's operation. Further, the adjustment mechanism 17 may incorporate an actuator and operate the actuator according to a command from the control unit 16 to rotate the illumination units 142 and 143 .

The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the first and second embodiments, the lighting units 141 to 143 are all made up of bar lighting members, but other lighting members may be used. For example, as shown in FIG. 6, a ring-shaped illuminating portion obtained by combining two half-illuminating members 141c each having a semi-annular light-emitting surface may be used as the central illuminating portion 141. FIG.

In the above-described embodiment, the present invention is applied to the technique of inspecting the substrate W having the notch Wn that is substantially U-shaped when viewed from above. is not limited to this. For example, the present invention can be applied to a technique for inspecting a substrate having a notch portion that is approximately V-shaped when viewed from above. Also, the present invention can be applied to a technique for inspecting a substrate on which an orientation flat or the like is formed.

Further, in the above-described embodiment, the upstream lighting unit 142 and the downstream lighting unit 143 are turned on in order when the notch Wn is imaged, but both may be turned on to image the notch Wn. In short, when the notch Wn is located in the imaging area IA, at least one of the second illumination light L2 and the third illumination light L3 should be applied to the imaging area IA.

In the above-described embodiment, the substrate is inspected based on the image of the peripheral portion We acquired while the substrate W is rotated once after the notch detection unit 144 detects the notch Wn. The number of rotations of W is not limited to "1". That is, after detecting the notch portion, the substrate W may be rotated a plurality of times, and a plurality of images of the peripheral portion We may be obtained while switching the illumination in the same manner as in the above embodiment. Then, the substrate W may be inspected based on these multiple images.

Furthermore, in the above embodiment, a so-called transmissive sensor composed of the light emitter 144a and the light receiver 144b is used as the notch detector 144, but other methods such as a reflective sensor may be used. Further, the position of the notch detection unit 144, that is, the notch detection position Ps is not limited to the vicinity of the upstream of the imaging area IA in the rotation direction R, and is arbitrary.

INDUSTRIAL APPLICABILITY The present invention can be applied to lighting technology in general used when an imaging unit captures an image of a peripheral edge of a substrate provided with a notch, and to substrate inspection technology in general for inspecting a substrate based on the image.

DESCRIPTION OF SYMBOLS 10... Board inspection apparatus 12... Board holding|maintenance part 13... Imaging part 14... Illumination device 17... Adjustment mechanism 141... Central illumination part (1st illumination part)
141a, 141b (first) bar lighting member 142 upstream lighting section (second lighting section, second bar lighting member)
143... Downstream lighting section (third lighting section, third bar lighting member)
144... Notch detection unit 161... Calculation unit (switching control unit, inspection unit)
AX...Rotating axis D1...First irradiation direction D2...Second irradiation direction D3...Third irradiation direction IA...Imaging area L1...First illumination light L2...Second illumination light L3...Third illumination light N...Surface normal Ps Notch detection position R... Rotation direction (of substrate) W... Substrate We... Periphery (of substrate) Wn... Notch Wnd... Downstream notch portion (of notch) Wnn... Non-notch Wnu... Upstream (of notch) Notch part X... Imaging direction

Claims (9)

A lighting device used for capturing an image of a notched portion provided in a part of a peripheral edge portion of a substrate rotated about a rotation axis and a non-notched portion of the peripheral edge portion excluding the notched portion by an imaging unit. hand,
The imaging unit is arranged on the side opposite to the center of rotation of the substrate with respect to the imaging area for imaging the substrate, and the imaging area is irradiated with the first illumination light when the non-notch portion is positioned in the imaging area. a first lighting unit that
A second illumination having a second irradiation direction orthogonal to a surface normal of the substrate in the imaging region and different from the first irradiation direction of the first illumination light when the notch is positioned in the imaging region. a second lighting unit that irradiates the imaging region with light;
When the notch portion is positioned in the imaging region, the third illumination light having a third irradiation direction orthogonal to the surface normal and different from both the first irradiation direction and the second irradiation direction is imaged. a third lighting unit that irradiates the region;
A lighting device comprising: The lighting device according to claim 1,
The second lighting unit is arranged upstream of the first lighting unit in the direction of rotation of the substrate,
The illumination device, wherein the third illumination unit is arranged downstream of the first illumination unit in the rotation direction of the substrate. The lighting device according to claim 1 or 2,
The illumination device further includes a switching control unit that individually switches between lighting and extinguishing of the first illumination unit, the second illumination unit, and the third illumination unit according to the rotation angle of the substrate in the rotation direction of the substrate. The lighting device according to claim 3,
When the cutout portion has an upstream cutout portion located on the upstream side and a downstream cutout portion located on the downstream side in the rotation direction,
The switching control unit
lighting only the first illumination unit when the non-notch portion is positioned in the imaging area;
turning on only the second illumination unit when the downstream notch portion is located in the imaging region;
An illumination device that lights only the third illumination unit when the upstream notch portion is located in the imaging area. The lighting device according to claim 3 or 4,
further comprising a notch detection unit that notifies that the rotation angle of the substrate has reached a predetermined angle by detecting the notch;
The switching control section switches lighting and extinguishing of the first lighting section, the second lighting section, and the third lighting section based on detection of the notch by the notch detection section. The lighting device according to any one of claims 1 to 5,
The lighting device further comprising an adjustment mechanism that adjusts the second irradiation direction and the third irradiation direction by displacing the second lighting unit and the third lighting unit. The lighting device according to any one of claims 1 to 6,
The first illumination unit is composed of a first bar illumination member having a bar-shaped light emitting surface extending in a direction orthogonal to both the axial direction of the rotation shaft and the first irradiation direction,
The second lighting unit is composed of a second bar lighting member having a bar-shaped light emitting surface extending in a direction orthogonal to both the axial direction and the second irradiation direction,
The third illumination unit is an illumination device comprising a third bar illumination member having a bar-shaped light emitting surface extending in a direction orthogonal to both the axial direction and the third irradiation direction. An illumination method used for capturing an image of a notched portion provided in a part of a peripheral edge portion of a substrate rotated around a rotation axis and a non-notched portion of the peripheral edge portion excluding the notched portion by an imaging unit. hand,
(a) a step of irradiating the imaging region with first illumination light from the opposite side of the rotation center of the substrate with respect to the imaging region where the substrate is imaged by the imaging unit;
(b) irradiating a second illumination light in a second irradiation direction orthogonal to the surface normal of the substrate in the imaging region and different from the first irradiation direction of the first illumination light;
(c) irradiating a third illumination light in a third irradiation direction orthogonal to the surface normal and different from both the first irradiation direction and the second irradiation direction;
When the non-notched portion is located in the imaging area for imaging the substrate by the imaging unit, performing the step (a),
An illumination method, wherein at least one of the step (b) and the step (c) is performed when the notch is positioned in the imaging area. A board inspection apparatus for inspecting a board having a notch formed in a part of the peripheral edge,
a substrate holder that rotates the substrate around a rotation axis while holding the substrate;
an imaging unit that captures a peripheral edge portion of the substrate rotated by the substrate holding portion to obtain a notch image of the notch portion and a non-notch portion image of the non-notch portion of the peripheral edge portion excluding the notch portion;
a lighting device according to any one of claims 1 to 7;
an inspection unit that inspects a peripheral portion of the substrate based on the cutout portion image and the non-cutout portion image acquired by the imaging unit while being illuminated by the illumination device;
A substrate inspection device comprising:

Images