WO2002023622A1

WO2002023622A1 - Detector and treatment system for detected body

Info

Publication number: WO2002023622A1
Application number: PCT/JP2001/007922
Authority: WO
Inventors: Mikio Takahashi
Original assignee: Tokyo Electron Limited
Priority date: 2000-09-13
Filing date: 2001-09-12
Publication date: 2002-03-21

Abstract

A detector for detected body installed across a transporting path for transporting, by a transporting mechanism, detected body to a plurality of designated positions and detecting whether the detected body is present or not on the transporting path, comprising a sensor part having a light emitting element and a light receiving element formed integrally with each other, a reflective body formed of two surfaces orthogonal to each other and having a large number of pair of reflective surfaces for emitting a reflected light along the same direction as an incident direction formed on the entire surface thereof, and a discrimination part for discriminating the presence of the detected body based on the reflective light obtained from the light receiving element, wherein the sensor part is disposed at a position capable of emitting a detection light to the pair of reflective surfaces and the detected body from a slanting direction.

Description

Specification

Detected object detection device and its processing system

Technical field

The present invention relates to an object detection device used mainly in a processing system for semiconductor wafers and the like, and a processing system using the same.

Background art

Generally, a semiconductor device is formed on a semiconductor wafer by various manufacturing processes such as a film forming process, an etching process, and an oxidation diffusion process. In these manufacturing processes, processing chambers and semiconductor manufacturing equipment dedicated to performing the processing are arranged as manufacturing lines, and semiconductor wafers are transferred between these chambers or between equipment using a transfer mechanism. Conveyed.

In the processing chamber into which the semiconductor wafer is loaded, the processing is performed according to a predetermined sequence. After the completion of this processing, the semiconductor wafer is carried out of the processing chamber by the transfer mechanism.

In such a semiconductor wafer transfer mechanism, the semiconductor wafer passes through each point on the transfer path in order to avoid a transfer error or to stop the transfer with minimal damage. It is important to check whether this is the case. Usually, this check is performed by arranging a detection device for detecting the presence or absence of a semiconductor wafer at a key point on the semiconductor wafer transfer path.

Here, a conventionally used detection device will be described. FIG. 8 is a perspective view showing a general sensor unit used in a conventional detection device, and FIGS. 9A and 9B show a state when the presence or absence of a semiconductor wafer is detected using the conventional detection device. FIGS. OA and 10B are explanatory diagrams illustrating the principle of detection when detecting the presence or absence of a semiconductor wafer using a conventional detection device.

As shown in FIG. 8, the sensor section 2 is configured integrally with a light emitting element 4 for emitting detection light and a light receiving element 6 for receiving reflected light of the emitted detection light. The light emitting element 4 emits light having a wavelength of about 700 nm, for example. The sensor unit 2 is connected via a cable 8 to a discriminating unit 10 composed of, for example, a micro computer. The determination unit 10 determines the presence or absence of a semiconductor wafer based on the result of light reception by the light receiving element 6.

In front of the light emitting element 4, there is arranged a horizontal polarization filter 11, which allows only horizontal polarization (see FIG. 1OA, for example) in FIG. 8, and a front face of the light receiving element 6. In FIG. 8, a vertical polarization filter 12 that is shifted by 90 degrees from the above polarization direction, that is, passes only the polarization in the vertical direction in FIG. 8, is arranged.

The reflector 14 is arranged at a predetermined distance in the irradiation direction of the detection light L1 of the sensor unit 2. The reflecting surface 14a of the reflector 14 is set so as to be substantially perpendicular to the above-mentioned irradiation direction, that is, the above-mentioned irradiation direction and the direction of the normal line to the above-mentioned reflecting surface 14a substantially coincide. Is set to The property of the reflecting surface 14a is that even if light having a vibration surface in a specific direction is irradiated, the polarization direction is disturbed and the vibration direction exists in all directions. Thus, the reflected light L 2 can be formed.

On the other hand, the surface of a general semiconductor wafer is a mirror surface, and when light incident on this surface is reflected, the vibration direction of the reflected light is the same as the vibration direction of the incident light. Without being disturbed, it is reflected while maintaining this, so that it is in the same state as the vibration direction of the incident light.

In such a detection device, the detection light L 1 emitted from the light emitting element 4 is radiated by the horizontal polarization filter 11 as detection light oscillating in the horizontal direction, and is applied to the reflection surface 1 of the reflector 14. 4a, or the light is reflected on the surface of the semiconductor wafer W as the object to be detected. The reflected light L 2 enters the longitudinal polarization filter 12 and the light receiving element 6. ,

Here, when the semiconductor wafer W does not exist in the detection space S, as shown in FIGS. 9A and 1OA, the detection light L1 is reflected by the reflection surface 14a which disturbs the vibration direction. Since the reflected light L 2 is reflected, the reflected light L 2 contains vibration components in all directions.

Therefore, the vertical vibration component of the reflected light L 2 passes through the vertically polarized finolators 12 and is detected by the light receiving element 6. It is determined that W does not exist in the detection space S.

On the other hand, as shown in FIGS. 9B and 1OB, when the semiconductor wafer W is present in the detection space S, the surface of the semiconductor wafer W is generally in a mirror state. Therefore, since the detection light L1 is reflected while being kept in the same vibration direction, the reflected light L2 vibrates in the horizontal direction. This reflection The light 2 cannot pass through the horizontal polarization filter 12 and is blocked (the optical path is bent), and the reflected light L 2 does not enter the light receiving element 6. A value of 0 determines that the semiconductor wafer W exists in the detection space S.

In the conventional detection apparatus as described above, it is assumed that the reflection surface, which is the surface of the semiconductor wafer W, is in a mirror state, and the reflected light L2 does not disturb the vibration direction of the detection light L1. ing.

However, when an anti-reflection film made of various compounds, for example, a nitride compound is deposited on the surface of the semiconductor wafer W, this surface is not in a mirror state but acts to disturb the vibration direction. Therefore, the detection light L1 is incident on the wafer surface on which the antireflection film is formed, and the reflected light L2 reflected includes vibration components in all directions as shown in FIG. 9A. As a result, the vertical vibration component of the reflected light L 2 passes through the vertical polarization filter 12 and is detected by the light receiving element 6, and the discrimination unit 10 determines that the semiconductor wafer W is In some cases, it may be determined that it does not exist even though it actually exists in the detection space S. Such erroneous judgments can cause the transport system to stop, which in turn will stop the production line.

In addition, as a technique for solving such a problem, a partially inclined surface is mounted on a mounting table for mounting a semiconductor wafer, which is disclosed in Japanese Patent Application Laid-Open No. H05-294405. Although a concave-shaped reflecting portion having the concave-shaped reflecting portion is also formed, in this case, the concave-shaped reflecting portion must be accurately formed on the surface of the mounting table, which results in an increase in cost. In addition, the location where the concave reflection portion is formed is limited. Therefore, the mounting position of the detection device is also restricted.

Disclosure of the invention

An object of the present invention is to provide an object detection device and a processing system thereof, which can reliably determine the presence of the object without being affected by the surface condition of the object. With the goal.

In order to achieve the above object, the present invention provides a sensor unit including a pair of a light emitting element and a light receiving element, and the sensor unit is arranged with a detection space in which an object to be detected can exist, The polygonal pyramids are arranged on the entire plane so that the faces of the adjacent polygonal pyramids face each other and are orthogonal to each other, and form a plurality of pairs of reflecting surfaces composed of two surfaces. A reflector that emits reflected light in the same direction as the incident direction of the detection light from the sensor; and a drive that controls the sensor unit, and the presence of the detected object based on the reflected light obtained from the light receiving element. The sensor unit is provided at a position where the detection light is emitted from the oblique direction to the reflection surface pair and the detection object to the detection object. Is when there is no object in the detection space. Since the detection light is mainly reflected toward the incident direction by the pair of reflecting surfaces of the reflector, the reflected light is received by the light receiving element and the object to be detected does not exist. On the other hand, when the object to be detected exists in the detection space, the above detection light enters the surface of the object to be detected from an oblique direction, so that the reflected light is directed to the normal to the surface of the object to be detected. The light is reflected in the opposite direction and is not detected by the light receiving element, and the presence of the object to be detected is accurately and reliably determined. It is possible to actually determine.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a schematic configuration of a device for detecting an object to be detected according to the present invention.

FIG. 2 is a diagram showing a cross-sectional configuration of a reflector used in the detection device of the present invention.

FIG. 3 is a diagram for explaining detection of a detection target (processing target).

FIG. 4 is a diagram showing a configuration example of a multi-chamber processing apparatus for a semiconductor wafer provided with the detection device of the present invention.

FIG. 5 is a configuration diagram showing a wafer positioning device in the multi-chamber processing apparatus.

FIG. 6 is a plan view showing a wafer fork provided with a reflector.

FIG. 7 is a diagram showing a main configuration of the positioning device. FIG. 8 is a diagram showing a configuration of a general sensor unit used in a conventional detection device.

9A and 9B are diagrams showing a configuration example for detecting the presence or absence of a semiconductor wafer by a conventional detection device.

FIGS. 10A and 10B are explanatory diagrams illustrating the detection principle when detecting the presence or absence of a semiconductor wafer using a conventional detection device.

FIG. 11 is a diagram showing a schematic configuration of a modified example of the device for detecting an object to be detected according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments according to the present invention will be described in detail. FIG. 1 is a diagram showing a conceptual configuration of a device for detecting an object to be detected according to the present invention. FIG. 2 is a diagram showing a cross-sectional configuration of a reflector used in the detecting device of the present invention. Is a diagram illustrating a state when a detection target (processing target) is detected. In these figures, the same components will be described with the same reference numerals. Further, in the following drawings, the detection light emitted from the light emitting element and the reflected light are light beams having a certain irradiation area, but are indicated by straight lines for convenience of description. In addition, in order to make it easier to understand the directivity of the emission direction and the incident direction, the position incident on the reflector and the position reflected therefrom are shown differently, but these positions are within the irradiation area. And the same position.

The detection device 20 for the object to be detected has a sensor unit 2. The sensor unit 2 includes a light emitting element 4 for emitting detection light L 1 and a reflected light L of the emitted detection light L 1. The light receiving elements 6 for receiving the light 2 and the light receiving elements 6 are integrally provided side by side in a pair. The light emitting element 4 emits light having a wavelength of about 700 nm, for example. In addition, these light emitting and receiving elements 4 and 6 are connected by a cable 8 to a discriminating section 10 composed of, for example, a computer with a microphone port. With this configuration, it is determined whether or not the object to be inspected exists based on the light receiving result of the light receiving element 6.

In addition, in front of the light-emitting element 4, a horizontal polarization filter 11 that allows only horizontal polarization (see FIG. 10) in the figure, for example, is arranged. A vertical polarization filter 12 that is shifted by 90 degrees from the above polarization direction, that is, passes only vertical polarization (see also FIG. 10) in the figure, is arranged. Note that these two filters 11 and 12 need not be provided as shown in FIG.

Further, a reflector 22 having a reflecting surface, which will be described later, is disposed at a predetermined distance in the irradiation direction of the detection light L1 of the sensor unit 2. The space between the reflector 22 and the sensor unit 2 is a detection space S.

Here, the reflector 22 has a reflection surface 22 a for mainly reflecting light so as to return to the direction of incidence of light, and a detection for the reflection surface 22 a is performed. The incident light direction of the light L1 is only a predetermined angle 61 from the direction of the normal HI of the reflective surface 22a when the reflective surface 22a is viewed from the above, that is, the normal direction. Inclined. Specifically, the reflecting surface 22a has a function such as a reflector that is provided at the end of a bicycle or the like and visually indicates that it is present, for example. I have. This has the function of reflecting light almost in the direction of incidence, regardless of the direction in which light enters, as long as the angle is within a certain opening angle centered on the normal to the reflecting surface. I have.

The reflecting surface 22a of such a reflector 22 is processed into a mirror surface state in which the surface disturbs the direction of light oscillation, and as shown in Fig. 2, the apex angle αΐ is approximately 90 degrees. The shape is such that many small quadrangular pyramids are arranged on the entire surface. This can be considered as a state in which many reflection surface pairs 24 in which two reflection surfaces are orthogonal to each other are arranged on the entire surface. By means of this pair of reflecting surfaces 24, if the light is incident on the reflecting surface on the incident side at an angle of incidence, the light incident from any angle will be in the same direction as this incident direction. reflected light Can be injected. In addition, as long as the reflecting surface emits reflected light in substantially the same direction as the incident direction, the present invention is not limited to the configuration described above, and can be used as a reflector in the detection device of the present invention. You. Further, in the present embodiment, a large number of quadrangular pyramids are arranged. However, the present invention is not limited to this, and when arranged, the faces of the adjacent pyramids face each other and are orthogonal (open). A polygonal pyramid having more than a quadrangular pyramid may be used as long as it can form a pair of reflecting surfaces composed of two surfaces arranged in a V-shape having an angle of about 90 degrees).

Next, the operation of detecting the presence or absence of the detection target 26 using the detection device 20 configured as described above will be described with reference to FIG.

First, as shown in FIG. 1, the detection light L 1 emitted from the light emitting element 4 of the sensor unit 2 is irradiated as the detection light vibrating in the horizontal direction by the horizontal polarization filter 11 and is reflected. The reflected light L 2 is reflected on the surface of the body 22, and enters the longitudinal polarization filter 12 and the light receiving element 6.

Here, as shown in FIG. 1, when the object to be detected does not exist in the detection space S, the detection light L 1 has an incident angle of 0 1 with respect to the reflection surface 22 a of the reflector 22. The light enters from an oblique direction. Then, due to the action of the reflection surface 22 a, the reflected light L 2 is reflected toward the incident direction of the detection light L 1, that is, toward the sensor unit 2. The reflected light L 2 includes vibration components in all directions.

Therefore, the vertical vibration component of the reflected light L 2 is The light passes through the optical filter 12 and is detected by the light receiving element 6, and as a result, the determination unit 10 determines that the object to be detected (see the object to be detected 26 shown in FIG. 3) does not exist in the detection space S. .

On the other hand, as shown in FIG. 3, when the detection target 26 is present in the detection space S, the surface of the detection target 26 is obliquely oriented (angle に対して with respect to the normal). 2) When the detection light L1 is incident from the above, this detection light L1 becomes reflected light L2 at the same angle 02 as the incident angle on the opposite side of the normal H1 according to the law of reflection. It is injected. Therefore, the reflected light L 2 does not enter the light receiving element 6, and as a result, the determination unit 10 determines that the detection target 26 exists in the detection space S.

In this case, the direction of the normal H 2 of the reflection surface of the detection target 26 in the detection space S needs to be different from the emission direction of the detection light L 1. That is, in this example, the angle Θ1 = 02 because the reflection surface 22a of the reflector 22 and the object 26 are substantially parallel to each other.

As described above, since the light is incident obliquely with respect to the surface direction of the detection target 26, the vibration direction of the reflected light L 2 depends on the surface state of the detection target 26. However, the reflected light L 2 is emitted to the opposite side across the normal line and does not return to the sensor unit 2. Therefore, even if the reflected light contains vibration components in all directions. Thus, the presence / absence of the object 26 can be accurately and reliably determined.

The angle 0 1 of the detection light L 1 with respect to the normal H 1 is such that the reflected light L 2 from the object 26 does not enter the light receiving element 6 and It is necessary that the angle is within an angle range that the reflection surface 22a of the reflector 22 can cover (an angle range that can reflect the reflected light L2 with respect to the incident direction of the detection light L1). It is in the range of 6 degrees to 25 degrees, preferably in the range of about 11 degrees to 20 degrees.

Next, an example will be described in which such an object detection device is mounted on a processing system to detect the presence or absence of a semiconductor wafer serving as an object.

FIG. 4 is a diagram showing an example of a configuration of a multi-chamber processing apparatus in a cluster tool as an example of the processing system. FIG. 5 is a diagram illustrating a semiconductor wafer positioning mechanism in the multi-chamber processing apparatus. FIG. 6 is a diagram showing a wafer fork provided with a reflector, and FIG. 7 is a diagram showing a main configuration of a positioning device.

The multi-chamber processing apparatus 30 includes two film forming chambers 32, 34 for depositing a nitride film such as a silicon nitride film or a titanium nitride film on a semiconductor wafer W to be processed. And an alignment chamber 36 equipped with an alignment mechanism 50 having the above-described detection device 20 and a cassette 44 a accommodating a large number of semiconductor wafers W. Then, the load chamber 46 for supplying the semiconductor wafer before processing and the empty cassette 44 b are mounted, and the unloading port chamber 4 for collecting the processed semiconductor wafer W is mounted. 8 and, for example, a hexagonal prism, and each side is connected to each of the chambers 32, 34, 46, 48 via gate valves G1, G2, G5, G6. The transport mechanism 42 for loading and unloading semiconductor wafers to and from each chamber The center chamber 38 is provided with an exhaust system (not shown) so that a vacuum state can be maintained by exhaust. The alignment chamber 36 is connected to the center chamber 38 by providing an opening that is always open.

Both the load and the unlock lock channel 46 and 48 have an airtight structure, and each of them has a force set stage (not shown) that can move up and down and rotate. A cassette is mounted on each of these cassette stages. In addition, an exhaust system (not shown) and gate doors G3 and G4 that open and close for mounting the cassette are provided.

If the inside of the loading and unloading lock channels 46 and 48 is in a vacuum state, the atmosphere in the outside working room (atmosphere) is established, and the gate doors G3 and G4 are opened. Alternatively, the cassettes 44a and 44b are attached and detached by a transport robot or the like. The transfer mechanism 42 in the center chamber 38 is attached to the end of the articulated arm 42a and the articulated arm 42a, which can bend and extend and rotate. And a transfer fork (not shown) for absorbing semiconductor wafers. The multi-joint arm is extended, a transfer fork is inserted into each chamber, and the transfer is performed between each chamber and the semiconductor wafer mounting portion.

Next, with reference to FIG. 5 to FIG. 7, positioning using the detection device 20 will be described.

The alignment chamber 36 is made of, for example, aluminum. Thus, it is formed in a box shape, and one side is air-tightly connected to the center chamber 38. The detection device 20 is provided as a component of a positioning mechanism 50 mounted in the alignment chamber 36.

The positioning mechanism 50 has a turntable 52 that holds and rotates the semiconductor wafer W. The turntable 52 is provided with a holding mechanism such as a vacuum chuck, so that even if the semiconductor wafer W rotates, it does not slide down. The rotary shaft 54 connected to the rotary base 52 penetrates through the bottom 36 a of the alignment chamber 36 and is connected to the rotary motor 56 to run. The rotating shaft 54 is attached to the bottom of the penetrating portion with a magnetic fluid seal 58 interposed therebetween, for example, and is rotatable while maintaining airtightness.

In addition, a transfer unit 60 for mounting the semiconductor wafer W on the turntable 52 is provided in the alignment chamber 36. The transfer section 60 is composed of a lifting / lowering port pad 62 that moves up and down at the time of delivery, and a Y-shaped wafer fork 64 that is horizontally attached to the upper end of the lifting / lowering port 62. Reply On the upper surface of the wafer fork 64, four support pins 66 are fitted so as to protrude upward, and the elevating door 62 is raised, and the upper end of these support pins 66 is lifted. The lifting / lowering port 62 is used to abut the back surface of the semiconductor wafer W, and to support the semiconductor wafer by pushing it up from the transport fork and to receive the semiconductor wafer. Penetrates the bottom 36 a of the sensor chamber 36, and through this bellows 68 The lifting rod 62 is moved up and down by an unillustrated actuator while maintaining the airtightness of the alignment chamber 36.

Further, the positioning mechanism 50 has a contour sensor 70 for detecting the outer peripheral contour of the semiconductor wafer W to be detected. The contour sensor section 70 includes a contour light emitting element 72 that emits a strip-like inspection light L5 provided on the ceiling 36 b of the alignment chamber 36 and an alignment chamber 70. And a line-shaped light receiving element for contour 74 provided at the bottom 36a of 36. Each of the mounting portions of the contour light emitting element 72 and the contour light receiving element 74 is provided with a transmission window 76, 78 made of, for example, quartz via a sealing member (not shown). The band-shaped inspection light L5 can be emitted from the light emitting element 72 to a position crossing the outer peripheral edge of the semiconductor wafer W placed at an appropriate position on the turntable 52. ing. The light emitting element for contour 72 and the light receiving element for contour 74 are connected to a displacement detecting unit 80 composed of, for example, a micro computer. The alignment is performed according to the eccentricity amount and the eccentric direction of the semiconductor wafer W obtained based on the output value of the light receiving element 74.

The sensor unit 2 of the detection device 20 is provided on the upper surface 36 b of the alignment chamber 36. In other words, as shown in FIG. 7, an opening 82 is opened in the upper surface 36b, and a sealing portion such as an O-ring is provided in the opening 82 for airtightness. A transmission window 84 made of quartz or the like is placed with the material 86 interposed therebetween, and the surrounding area is fixed with a mounting frame 88. Then, the sensor section 2 is fixed to a bending bracket 92, one end of which is fixed to a mounting frame 88 by a bolt 90 outside the transmission window 84. The output end of the sensor section 2 is a cable 8 Is connected to the discriminating unit 10 via. For example, assuming that the semiconductor wafer W is horizontal, the bending fitting 92 is inclined at an angle of 01, for example, about 15 degrees with respect to the vertical direction (normal line) as described above, and the sensor section is bent. 2 is bent so that it is fixed.

On the other hand, as shown in FIGS. 6 and 7, the reflector 22 is provided horizontally on one side of a wafer fork 64 that moves up and down. In this case, as the wafer fork 64 is moved up and down, the reflector 22 also moves up and down by a stroke of the distance XI. The detection light L 1 is set to be incident on the reflection surface 22 a of the reflector 22.

Next, the processing steps of the semiconductor wafer W in the processing apparatus configured as described above will be described.

First, the inside of each of the chambers, except the mouthpiece chamber 46 and the unloading chamber 48, is evacuated to reach a predetermined vacuum. Of course, all chambers may be exhausted once.

Thereafter, the gate door G3 of the load lock channel 46 is opened, and a force set 44a containing, for example, 25 unprocessed semiconductor wafers W is placed on a cassette stage (not shown). the gate door G 3 to close and subsequently mounted, Ri by the indoor for example inert gas, the N ₂ gas Nono. After loading, this load lock channel The inside of the bar 46 is evacuated to a specified vacuum. In the same way, an empty cassette 44b is attached to the unloading port chamber 48.

Next, the gate valve G1 is opened, the multi-joint arm 42a of the transfer mechanism 42 is extended under vacuum, and a transfer fork is inserted into the cassette 44a to receive the semiconductor wafer. Next, the transfer fork is retracted, and the semiconductor wafer W is loaded into the center chamber 38, and then the gate valve G1 is closed.

Next, the multi-joint arm 42 a is rotated ■ extended, and the semiconductor wafer W is carried into the alignment chamber 36, and is placed on the wafer fork 64. Then, as will be described later, the positioning mechanism 50 detects a position shift and performs positioning so as to be at a correct position. The semiconductor wafer W after the completion of the alignment is again carried out to the center chamber 38 by the transfer mechanism 42.

Then, the semiconductor wafer W is sequentially carried into the film forming chambers 32 and 34, and a predetermined film is formed on the semiconductor wafer W in each of the film forming chambers 32 and 34. Perform processing. After the completion of the film forming process, the processed semiconductor wafer W is stored by the transfer mechanism 42 in the empty cassette 44 b in the unload lock chamber 48.

Next, the positioning operation by the positioning mechanism 50 will be described in detail.

First, the semiconductor held by the transport fork of the transport mechanism 42 The wafer W is carried into the center chamber 38 and the alignment chamber 36, and stops at a predetermined position. Next, the wafer fork 64 is raised, and the upper end of the support pin 66 is brought into contact with the back surface of the semiconductor wafer W, and the semiconductor wafer W is further pushed up and received from the transfer fork. Thereafter, the transfer is completed by the withdrawal of the transfer fork out of the alignment chamber 36.

Next, the wafer fork 64 is lowered to a position below the turntable 52. At this time, the semiconductor wafer W is delivered to and held by the turntable 52. Next, the turntable 52 drives the contour sensor 70 while rotating the semiconductor wafer W by one or more rotations, and receives the inspection light L 5 from the contour light emitting element 72 by the contour light receiving element 74. Thus, for example, the position of the contour of the semiconductor wafer W is detected based on the orientation flat.

From this detection result, the displacement detection unit 80 obtains a displacement correction amount of the semiconductor wafer, and performs the position correction by rotating the turntable 52 according to the displacement correction amount. This position correction is performed, for example, so as to match the semiconductor wafer holding position of the film carrier to be carried in next. In such a multi-chamber single-processing apparatus, one unified reference position is set for all the conductive wafer holding units (for example, a susceptor in a film forming chamber) in the apparatus. In this case, the position is corrected so as to be the reference position.

During such a series of operations, the detection light L 1 is reflected by the reflector 22 from the light emitting element 4 of the sensor unit 2 of the detection device 20. The semiconductor wafer W is injected toward the surface 22 a, and whether or not the semiconductor wafer W is held on the wafer fork 64 is constantly monitored.

When the wafer fork 64 does not hold the semiconductor wafer W, the detection light L1 is incident on the reflection surface 22a of the reflector 22 and reflected there, as shown in FIG. 1 described above. The reflected light L2 is emitted in the same or almost the same direction as the incident direction. Then, the reflected light L 2 is received by the light receiving element 6 of the sensor unit 2, and from the light receiving result, the determination unit 10 determines that the semiconductor wafer W is not held. On the other hand, when the semiconductor wafer W is held on the wafer fork 64, the detection light L1 is reflected in the opposite direction across the normal on the surface of the semiconductor wafer. The reflected light does not enter the light receiving element 6, and the determination unit 10 determines that the semiconductor wafer W is held. Note that, also on the semiconductor wafer W on the turntable 52, the detection light L1 is reflected by the semiconductor wafer W in the opposite direction, so that the determination unit 10 determines that the semiconductor wafer W is held. ing. Therefore, since the reflected light is not reflected in the direction of the light receiving element 6, it is not affected by the surface condition of the semiconductor wafer, that is, regardless of the type of film formed on the surface of the semiconductor wafer W, The presence or absence of W can be accurately and reliably determined.

On the basis of the result of the determination of the presence or absence of such a semiconductor wafer, the transport of the semiconductor wafer is performed by an intelligent method. For example, the determination result of “wafer present” indicates that the detection device 20 holds the semiconductor wafer W on the turntable 52 of the positioning mechanism 50. In the event that there is an error, an interface is automatically provided by the program sequence to prevent another semiconductor wafer W from being carried into the alignment mechanism 50 during transfer or processing. The transfer operation is stopped. Such interlocks are often generated by software.

In the above-described embodiment, a multi-chamber processing apparatus having the film forming chambers 32 and 34 is described as an example. However, the present invention is not limited to this, and may include an etching apparatus, an oxidation diffusion apparatus, and a sputtering apparatus. In addition, the object to be transported is not limited to a semiconductor wafer, but may be a glass substrate, an LCD substrate, or the like. Here, the example in which the detection device 20 of the present invention is provided in the positioning mechanism has been described. However, the present invention can be applied to other devices such as a moving path of a driving member such as each gate valve in the center chamber. By arranging as shown in FIG. 1 as a detection space, it is also possible to detect the driving state of the driving member. In particular, the reflector may be prepared and attached separately to the support, or may be attached to the drive member itself and implemented. For example, when applied to a gate valve or the like, the reflector 22 may be provided at the bottom of the chamber. For a transfer arm, etc., a reflector is attached to the arm, a plurality of sensor units are arranged on the movement path of the transfer arm, and the sensor output is monitored as needed. In addition, it is possible to grasp the current position and the driving state of the transfer arm.

In the embodiment described above, the reflection surface 22 of the reflector 22 is used. a has a shape in which a large number of minute quadrangular pyramids whose surface is disturbed in a mirror state that disturbs the direction of light oscillation are arranged, but it is not limited to this.For example, it has two orthogonal surfaces A plurality of groove-shaped (line-shaped) reflecting surfaces may be arranged in a row. In particular, as shown in FIG. 11, it is configured using a sensor unit having no filter. In this configuration, it is necessary to adjust the position of the sensor section in the line direction of the reflection surface.

As described above, according to the object detection device of the present invention and the processing system using the same, the following excellent operational effects can be obtained.

When no object is present in the detection space, the detection light is reflected mainly by the reflecting surface of the reflector toward the incident direction. It is possible to determine that the object is not present, and when the object is present in the detection space, the reflected light is incident on the surface of the object from an oblique direction. The light does not return to the light receiving element because it is reflected in the direction opposite to the normal to the surface of the detection object. Therefore, it can be determined that the object to be detected exists.

In this way, regardless of the direction of vibration of the reflected light depending on the state of the surface of the detection target, the incident direction of the reflected light is not directed toward the light receiving element. The presence or absence of a test object can be accurately and reliably determined.

Industrial applicability

The detection device for a detected object according to the present invention includes: a sensor unit in which a pair of a light emitting element and a light receiving element are integrally formed; A plurality of identical polygonal pyramids are arranged on the entire plane so that the faces of the adjacent polygonal pyramids face each other and are orthogonal to each other on a plane where a detection object is allowed to exist. A plurality of reflective surface pairs formed of two surfaces, and a reflector that emits reflected light in the same direction as the incident direction of the detection light from the light-emitting element. The normal direction of the body does not match the normal direction of the object to be reflected, and the sensor section emits the detection light to the pair of reflecting surfaces from a direction oblique to the normal direction of the reflector. Placed in

According to this, when the object to be detected does not exist in the detection space, the detection light is mainly reflected toward the incident direction by the pair of reflecting surfaces of the reflector, so that the reflected light is received. The detection light can be received by the element to determine that the object is not present. On the other hand, when the object is present in the detection space, the above detection light is incident on the surface of the object obliquely. However, this reflected light is reflected in the direction opposite to the normal to the surface of the object and is not detected by the light receiving element, and the presence of the object is accurately and reliably determined. It is possible to do it.

According to the present invention, there is provided an object detection device and a processing system thereof, which can reliably determine the presence of the object without being affected by the surface condition of the object.

Claims

The scope of the claims

1. A light emitting element that emits detection light,

A light receiving element for receiving the reflected light of the detection light,

A reflector which is disposed with respect to the light emitting element via a detection space of the object to be detected, and which has a reflecting surface mainly reflecting light in a light incident direction;

With

The reflector and the light-emitting element are arranged such that the detection light on the reflection surface is incident at a predetermined angle from the normal direction of the reflection surface. Of the object to be detected

2. The incident direction of the detection light on the reflection surface of the object to be detected, which may be located in the detection space, is inclined by a predetermined angle from the normal direction of the reflection surface of the object to be detected. 2. The detection device for an object to be detected according to claim 1, wherein:

3. The device for detecting an object to be detected according to claim 1, wherein the light emitting element and the light receiving element are provided side by side and integrally provided.

4. In a processing system that performs predetermined processing on the object,

A processing system, wherein the detection device is mounted so that a conveyance path of the object passes through the detection space.

5. The above detection device is

A turntable for holding and rotating the object to be processed,

A transfer mechanism for transferring the object to be processed to the turntable; It is provided in a positioning device having a contour sensor unit for detecting an outer peripheral contour of the object to be processed, and a misregistration detecting unit for calculating a misregistration amount based on a detection result of the contour sensor unit. The processing system according to claim 4.

6. The sensor unit composed of a pair of light-emitting element and light-receiving element and the sensor unit are arranged with a detection space in which the object to be detected can exist,

A plurality of identical polygonal pyramids are arranged on the entire plane such that the faces of the adjacent polygonal pyramids face each other and are orthogonal to each other, and form a plurality of reflection surface pairs composed of two surfaces. A reflector that emits reflected light in the same direction as the incident direction of the detection light from the light emitting element;

A determination unit that controls the driving of the sensor unit and determines the presence of the detection target based on the reflected light obtained from the light receiving element;

The object detection device, wherein the sensor section is disposed at a position where the detection light is emitted from the oblique direction to the reflection surface and the object.

7. In the above detection device,

The detection light incident on the reflector,

The object to be detected according to claim 6, wherein the light enters the reflector from an oblique direction within a range of 6 degrees to 25 degrees with respect to the direction of the normal to the reflection surface of the reflector. Detection device.

8. In the above detection device,

In a range where the detection light from the light emitting element is incident on the reflection surface. The device for detecting an object to be detected according to claim 1, wherein the reflector is movable in the detection space.

9. In the above detection device,

The sensor section is configured so that a first optical path of the detection light emitted from the light emitting element and a second optical path of the reflected light of the detection light reflected and emitted by the pair of reflection surfaces of the reflector are in the same direction. The device for detecting an object to be detected according to claim 6, wherein the light-emitting element and the light-receiving element are arranged so as to follow.

1 0. In the above detection device,

The discriminating unit includes:

Detection light emitted from the light emitting element is incident obliquely toward the reflection surface of the reflector, and a detection signal is obtained in which the light receiving element receives reflected light reflected in a direction along the incident direction. In this case, it is determined that the object to be detected does not exist in the detection space,

Detection light emitted from the light emitting element is incident obliquely toward the reflecting surface of the reflector, and the incident light is reflected on the opposite side beyond the normal line of the reflector and is directed toward the light receiving element. 7. The device for detecting a detected object according to claim 6, wherein, if the object is not ejected, the detected object is determined to be present in the detection space.

1 1. A detecting device provided on a transport path by a transport mechanism for transporting a detected object to a plurality of designated locations, and detecting whether the detected object is present on the transport path.

The direction of detection light emission and its A sensor section configured so that the incident direction of the reflected light of the detection light is the same,

A determining unit that controls the driving of the sensor unit and determines the presence of the object to be detected based on the reflected light obtained from the light receiving element;

The reflector and the sensor unit are arranged with the conveyance path of the object to be detected interposed therebetween, and the sensor unit is arranged at a position where detection light is emitted to the reflection surface pair and the object to be detected from an oblique direction. A device for detecting an object to be detected.

1 2. A detection device provided on a moving path along which the driving member moves, and detecting whether the driving member has moved on the moving path.

A sensor unit configured such that the direction of emission of the detection light and the direction of incidence of the reflected light of the detection light are the same between the pair of light emitting element and the light receiving element;

A plurality of identical polygonal pyramids are arranged on the entire plane such that the faces of the adjacent polygonal pyramids face each other and are orthogonal to each other, and form a plurality of reflection surface pairs composed of two surfaces. A reflector that emits reflected light in the same direction as the incident direction of the detection light from the light emitting element; A determining unit that controls the driving of the sensor unit and determines the presence of a driving member based on the reflected light obtained from the light receiving element;

The reflector and the sensor unit are arranged so as to sandwich the movement path of the drive member, and the sensor unit is arranged at a position where detection light is emitted to the reflection surface pair and the drive member from an oblique direction. A device for detecting an object to be detected, characterized in that: