WO2013035696A1 - Substrate transfer apparatus and substrate processing apparatus - Google Patents

Abstract

This substrate transfer apparatus is provided with: a transfer unit, which transfers a strip-shaped substrate having a circuit pattern formed thereon, said circuit pattern including repeated pattern portions at a predetermined cycle; a position detector which outputs, during a time when the substrate is being transferred by means of the transfer unit, detection signals at least at two areas in the direction that intersects the transfer direction of the substrate, said detection signals corresponding to the repeated pattern portions in the circuit pattern; a calculating apparatus, which calculates, on the basis of detection results obtained from the position detector, information relating to deformation and/or positional shift of the substrate; and a control system for correction, which corrects the deformation and/or positional shift of the substrate on the basis of results calculated by means of the calculating apparatus.

Description

Substrate transport apparatus and substrate processing apparatus

The present invention relates to a substrate transfer apparatus and a substrate processing apparatus.
This application claims priority based on Japanese Patent Application No. 2011-193244 for which it applied on September 5, 2011, and uses the content here.

As display elements constituting display devices such as display devices, for example, liquid crystal display elements, organic electroluminescence (organic EL) elements, electrophoretic elements used in electronic paper, and the like are known. As one of methods for manufacturing these elements, for example, a method called a roll-to-roll method (hereinafter simply referred to as “roll method”) is known (for example, refer to Patent Document 1).

In the roll method, a single sheet-like substrate wound around a substrate supply side roller is sent out, the substrate is transported while being wound up by a substrate recovery side roller, and the substrate is sent out after being sent out. In this manner, a pattern such as a display circuit or a driver circuit is sequentially formed on a substrate until it is formed. In recent years, processing apparatuses that form highly accurate patterns have been proposed.

International Publication No. 2008/129819

By the way, in the roll method as described above, there is a demand for a technology that enables a display element to be manufactured with high accuracy on a belt-like substrate. For example, a technology for transporting a belt-like substrate with high accuracy is required.

Therefore, an object of an aspect of the present invention is to provide a substrate transport apparatus and a substrate processing apparatus that can transport a band-shaped substrate with high accuracy.

According to the first aspect of the present invention, a transport unit that transports a belt-like substrate on which a circuit pattern including a repetitive pattern unit having a predetermined period is formed, and a transport direction of the substrate while the substrate is transported by the transport unit Information relating to at least one of deformation or misalignment of the substrate based on the position detector that outputs a detection signal corresponding to the repeated pattern portion in the circuit pattern in at least two places in the intersecting direction, and the detection result of the position detector There is provided a substrate transport apparatus that includes a calculation device that calculates the above and a correction control system that corrects at least one of deformation or displacement of the substrate based on the result calculated by the calculation device.

According to the second aspect of the present invention, the substrate transport apparatus according to the first aspect of the present invention and the surface to be processed on which the circuit pattern is formed among the substrates transported by the substrate transport apparatus are processed. The correction control system provided in the substrate transport apparatus includes a processing unit that performs correction, and a substrate processing apparatus that corrects at least one of deformation or displacement of a surface to be processed in a processing region by the processing unit is provided.

According to the aspect of the present invention, the belt-like substrate can be conveyed with high accuracy.

It is a figure which shows the structure of the substrate processing apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the conveying apparatus and exposure apparatus which concern on this embodiment. It is a figure which shows the structure of a part of conveyance apparatus and exposure apparatus which concern on this embodiment. It is a figure which shows the structure of the to-be-processed surface of the board | substrate which concerns on this embodiment. It is a figure which shows the structure of a part of conveyance apparatus and exposure apparatus which concern on another embodiment of this invention. It is a figure which shows the detailed structure of some conveyance apparatuses and exposure apparatuses which concern on this embodiment. It is a figure which shows the detailed structure of some conveyance apparatuses and exposure apparatuses which concern on this embodiment. It is a figure which shows the structure of the measuring device which concerns on this embodiment. It is a figure which shows the structure of the measuring device which concerns on this embodiment. It is a figure which shows the structure of the measuring device which concerns on this embodiment. It is a figure which shows the other structure of the measuring device which concerns on this embodiment. It is a figure which shows the other structure of the measuring device which concerns on this embodiment.

Hereinafter, the present embodiment will be described with reference to the drawings.
[First embodiment]
FIG. 1 is a schematic diagram showing a configuration of a substrate processing apparatus 100 according to the first embodiment.
As shown in FIG. 1, the substrate processing apparatus 100 performs processing on a substrate supply unit 2 that supplies a strip-shaped substrate (for example, a strip-shaped film member) S and a surface (surface to be processed) Sa of the substrate S. The substrate processing unit 3, the substrate recovery unit 4 that recovers the substrate S, and a control unit CONT that controls these units are provided.

The substrate processing unit 3 performs a variety of processes on the surface of the substrate S after the substrate S is sent out from the substrate supply unit 2 until the substrate S is recovered by the substrate recovery unit 4. 100. The substrate processing apparatus 100 can be used when a display element (electronic device) such as an organic EL element or a liquid crystal display element is formed on the substrate S.

In this embodiment, an XYZ coordinate system is set as shown in FIG. 1, and the following description will be given using this XYZ coordinate system as appropriate. In the XYZ coordinate system, for example, the X axis and the Y axis are set along the horizontal plane, and the Z axis is set upward along the vertical direction. Also, the substrate processing apparatus 100 transports the substrate S from the minus side (− side) to the plus side (+ side) along the X axis as a whole. In that case, the width direction (short direction) of the strip | belt-shaped board | substrate S is set to the Y-axis direction.

As the substrate S to be processed in the substrate processing apparatus 100, for example, a foil such as a resin film or stainless steel can be used. For example, the resin film is made of polyethylene resin, polypropylene resin, polyester resin, ethylene vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, vinyl acetate resin, etc. Can be used.

The substrate S can have a low coefficient of thermal expansion so that its dimensions do not substantially change even when it receives heat at a relatively high temperature (for example, about 200 ° C.) (thermal deformation is small). For example, an inorganic filler can be mixed with a resin film to reduce the thermal expansion coefficient. Examples of the inorganic filler include titanium oxide, zinc oxide, alumina, silicon oxide and the like.

The dimension in the width direction (short direction) of the substrate S is, for example, about 1 m to 2 m, and the dimension in the length direction (long direction) is, for example, 10 m or more. Of course, this dimension is only an example and is not limited thereto. For example, the dimension in the Y direction of the substrate S may be 1 m or less, 50 cm or less, or 2 m or more. Moreover, the dimension of the X direction of the board | substrate S may be 10 m or less.

The substrate S is formed to have flexibility. Here, the term “flexibility” refers to the property that the substrate can be bent without being broken or broken even if a force of its own weight is applied to the substrate. In addition, flexibility includes a property of bending by a force of about its own weight. The flexibility varies depending on the material, size, thickness, or environment such as temperature of the substrate. As the substrate S, a single strip-shaped substrate may be used, but a configuration in which a plurality of unit substrates are connected and formed in a strip shape may be used.

The substrate supply unit 2 supplies and supplies the substrate S wound in a roll shape to the substrate processing unit 3, for example. In this case, the substrate supply unit 2 is provided with a shaft around which the substrate S is wound, a rotation drive device that rotates the shaft, and the like. In addition, for example, a configuration in which a cover portion that covers the substrate S wound in a roll shape or the like may be provided. In addition, the board | substrate supply part 2 is not limited to the mechanism which sends out the board | substrate S wound by roll shape, What is necessary is just to include the mechanism which sends out the strip | belt-shaped board | substrate S sequentially in the length direction.

The substrate collection unit 4 collects the substrate S that has passed through the substrate processing apparatus 100 included in the substrate processing unit 3 in a roll shape, for example. Similar to the substrate supply unit 2, the substrate recovery unit 4 is provided with a shaft for winding the substrate S, a rotational drive source for rotating the shaft, a cover for covering the recovered substrate S, and the like. Alternatively and / or additionally, when the substrate S is cut into a panel shape in the substrate processing unit 3, the substrate recovery unit 4 is wound in a roll shape, for example, the substrate S is recovered in a stacked state. The substrate S may be collected in a state different from the state.

The substrate processing unit 3 transports the substrate S supplied from the substrate supply unit 2 to the substrate recovery unit 4 and processes the surface Sa of the substrate S during the transport process. The substrate processing unit 3 includes a processing apparatus 10 and a transfer apparatus 20.

FIG. 2 is a diagram illustrating the configuration of the processing device 10 and the transport device 20.
As shown in FIG. 2, the processing apparatus 10 has an exposure apparatus EX.
In addition to the exposure apparatus EX, the processing apparatus 10 may have a configuration in which various apparatuses for forming, for example, an organic EL element on the surface Sa of the substrate S are provided.

Examples of such an apparatus include a partition forming apparatus for forming a partition on the surface Sa to be processed, an electrode forming apparatus for forming an electrode, and a light emitting layer forming apparatus for forming a light emitting layer. More specifically, a droplet coating apparatus (for example, an ink jet type coating apparatus), a film forming apparatus (for example, a plating apparatus, a vapor deposition apparatus, a sputtering apparatus), a developing apparatus, a surface modification apparatus, a cleaning apparatus, a pattern correction apparatus, etc. Can be mentioned. Each of these apparatuses is appropriately provided along the transport path of the substrate S.

The exposure apparatus EX includes an illumination apparatus IL, a mask stage MST, a projection optical system PL, and a substrate stage SST. The illumination device IL illuminates the exposure light ELI on the mask M held on the mask stage MST. Mask stage MST is provided so as to be movable while holding mask M on which a pattern (not shown) is formed.

The projection optical system PL projects an image of the exposure light ELI through the pattern formed on the mask M onto the projection area PA. The substrate stage SST guides the substrate S so that the substrate S passes through the projection area PA. The substrate stage SST has a support surface 15 that supports the back surface Sb of the substrate S opposite to the processing surface Sa. The support surface 15 is formed flat so as to be parallel to the XY plane.

The exposure apparatus EX has a correction mechanism 50 that adjusts the shape of the image projected on the projection area PA and the position in the X and Y directions. The correction mechanism 50 includes a drive device 50a that moves (finely moves) some of the plurality of optical elements constituting the projection optical system PL, such as a refractive element (lens, parallel plate, etc.) and a reflective element.

For example, the drive device 50a can adjust the shape and position of the image projected on the projection area PA by moving or tilting the refractive element or the reflective element under the control of the control unit CONT.

In the case where the projection optical system PL includes a reflective element, the driving device 50a may deform the reflective surface of the reflective element in order to adjust the shape of the image projected on the projection area PA.

Further, the exposure apparatus EX is provided with an alignment sensor (including a microscope objective lens, an image sensor, etc.) 29 for detecting alignment marks and the like formed on both sides in the width direction (Y direction) of the substrate S. .

FIG. 3 is a diagram illustrating a configuration when the surface to be processed Sa of the substrate S is viewed.
As shown in FIG. 3, the exposure apparatus EX has four projection optical systems PL in the Y direction, and four projection areas PA are formed in the Y direction. The correction mechanism 50 is provided for each projection optical system PL. Therefore, the position and shape of the image projected in each projection area PA in the X direction and the Y direction can be adjusted independently for each projection area PA.

Returning to FIG. 2, the conveyance device 20 includes a conveyance unit 21, a position detection unit 22, a calculation unit 23, and a correction mechanism 60.
The transport unit 21 transports the substrate S so that the substrate S moves on the substrate stage SST. The transport unit 21 includes an upstream roller 24, a downstream roller 25, an upstream air pad 26, and a downstream air pad 27.

The transport unit 21 transports the substrate S while applying tension to the substrate S using the upstream roller 24 and the downstream roller 25. The controller CONT can adjust the transport speed of the substrate S by the upstream roller 24 and the downstream roller 25.

The upstream roller 24 is disposed on the upstream side in the transport direction of the substrate S with respect to the processing apparatus 10. The upstream roller 24 includes nip rollers 24A and 24B that sandwich the substrate S in the Z direction. The downstream roller 25 is disposed on the downstream side in the transport direction of the substrate S with respect to the processing apparatus 10. The downstream roller 25 has nip rollers 25A and 25B that sandwich the substrate S in the Z direction.

The upstream air pad 26 is disposed on the upstream side in the transport direction of the substrate S with respect to the processing apparatus 10. The upstream air pad 26 is disposed at the −X side end of the substrate stage SST.
The upstream air pad 26 includes a first pad 26A and a second pad 26B. The first pad 26 </ b> A is disposed on the + Z side of the substrate S, and forms a gas layer between the substrate S and the surface Sa to be processed. The second pad 26B is disposed on the −Z side of the substrate S, and forms a gas layer with the back surface Sb of the substrate S.

The downstream air pad 27 is disposed downstream of the processing apparatus 10 in the transport direction of the substrate S. The downstream air pad 27 is disposed at the + X side end of the substrate stage SST.
The downstream air pad 27 has a first pad 27A and a second pad 27B. The first pad 27A is disposed on the + Z side of the substrate S, and forms a gas layer between the substrate S and the surface Sa to be processed. The second pad 27B is disposed on the −Z side of the substrate S, and forms a gas layer with the back surface Sb of the substrate S.

As described above, the transport unit 21 applies the tension to the substrate S by the upstream roller 24 and the downstream roller 25, and the processed surface Sa and the back surface Sb of the substrate S with the upstream air pad 26 and the downstream air pad 27. Support in a non-contact state. For this reason, the substrate S is supported on the support surface 15 in a non-contact state on the support surface 15 of the substrate stage SST.

The position detection unit 22 detects position information including the deformation amount and displacement amount of the substrate S. The position detection unit 22 includes an illumination system 31 including a light source, a light transmission reflection member 32, a light reflection member 33, a prism 34, a prism 35, a light guide member 36, and a light detection unit 37.

The light from the illumination system 31 including a light source that emits a coherent beam such as a laser and a beam shaping optical element is shaped into a slit-like light (slit light L) extending in the Y direction, and then in the + X direction. It is injected. The light transmitting and reflecting member 32 reflects a part (first slit light L1) of the slit light L emitted from the illumination system 31 toward the substrate S (−Z direction) and a part (second slit). Transmits light L2). The light reflecting member 33 reflects the second slit light L2 transmitted through the light transmitting and reflecting member 32 toward the substrate S (−Z direction).

The prism 34 tilts the traveling direction of the first slit light L1 reflected by the light transmitting / reflecting member 32 to the + X side. The prism 35 tilts the traveling direction of the second slit light L2 reflected by the light reflecting member 33 to the −X side. By the prism 34 and the prism 35, the first slit light L1 and the second slit light L2 are irradiated to the same irradiation area LA (area extending in a slit shape in the Y direction). In the irradiation region LA, the first slit light L1 and the second slit light L2 having different optical path lengths intersect each other at a predetermined angle with respect to the X direction, and therefore, a one-dimensional interference fringe having a pitch in the X direction (hereinafter, L3) is formed.

Note that an apparatus for measuring the position by forming interference fringes on the irradiated surface by the two-beam interference method is disclosed in, for example, US Pat. No. 4,701,0026.

The light guide member 36 guides the light component L4 reflected in the + Z direction out of the interference light L3 formed in the irradiation area LA as it is in the + Z direction. The light detection unit 37 detects the light component L4 guided by the light guide member 36. The calculation unit 23 calculates the position information of the substrate S based on the detection result in the light detection unit 37. The calculation result in the calculation unit 23 is transmitted to the control unit CONT.

In addition, as shown in FIG. 3, the position detection part 22 is provided in two places of the direction (Y direction) which cross | intersects the conveyance direction (X direction) of the board | substrate S. As shown in FIG. Therefore, the irradiation area LA is formed at two places in the Y direction of the substrate S, and the position information of the substrate S can be detected in these two irradiation areas LA. Note that, as an example, the irradiation region LA is set at one location on each of the + Y side end portion and the −Y side end portion of the pattern formation region PT in which a circuit pattern such as a wiring is formed in the substrate S.

The correction control system 60 corrects at least one of deformation and displacement of the substrate S estimated based on the detection result of the position detection unit 22 via the control unit CONT. The correction control system 60 corrects the two-dimensional distortion of the pattern formation region on the substrate S by individually adjusting the position, posture, conveyance speed, and the like of the upstream roller 24 and the downstream roller 25.

The substrate processing apparatus 100 configured as described above manufactures display elements (electronic devices) such as an organic EL element and a liquid crystal display element by a roll method under the control of the control unit CONT.
Hereinafter, a process of manufacturing a display element using the substrate processing apparatus 100 having the above configuration will be described (see FIG. 1).

First, a belt-like substrate S wound around a roller (not shown) is attached to the substrate supply unit 2.
The control unit CONT rotates a roller (not shown) so that the substrate S is sent out from the substrate supply unit 2. And this board | substrate S which passed the board | substrate process part 3 is wound up with the roller not shown provided in the board | substrate collection | recovery part 4. FIG. By controlling the substrate supply unit 2 and the substrate recovery unit 4, the surface Sa to be processed of the substrate S can be continuously transferred to the substrate processing unit 3.

The control unit CONT appropriately transfers the substrate S in the substrate processing unit 3 by the transfer device 20 of the substrate processing unit 3 after the substrate S is sent out from the substrate supply unit 2 and taken up by the substrate recovery unit 4. Constituent elements including circuit patterns for display elements are sequentially formed on the substrate S by the processing apparatus 10 while being conveyed. In this process, when processing is performed by the exposure apparatus EX, the exposure pattern may be superimposed on the circuit pattern formed on the substrate S.

According to the present embodiment, prior to the exposure processing, position information such as the deformation amount and displacement amount of the substrate S is calculated based on the state of the circuit pattern already formed on the substrate S, and the calculation result is determined according to the calculation result. By adjusting the deformation and misalignment of the substrate S and the shape and position of the projection area PA of the exposure light ELI, the accuracy of exposure processing (such as overlay accuracy) can be improved.

With reference to FIG. 4, the detection of the positional information on the substrate S will be described.
As shown in FIG. 4, for example, a circuit pattern 30 for a display portion of an AMOLED display is formed on the surface Sa of the substrate S in the previous process by the above processing, for example. The circuit pattern 30 includes, for example, a fine pattern portion 30b for TFT together with the wiring portion 30a. A plurality of wiring portions 30a are formed in a line along a direction (Y direction) intersecting the transport direction (X direction) of the substrate S. A plurality of rows of the wiring portions 30a are formed at equal intervals in the transport direction (X direction) of the substrate S.

The fine structure pattern portion 30b for TFT is a portion where several TFT patterns are densely arranged for each pixel of the display, and usually a plurality of patterns having a line width of about several μm to several tens of μm in the XY direction. Are lined up.

Thus, since the pixels in the display portion of the display are arranged at a constant pitch in the X direction and the Y direction, the wiring portion 30a and the fine structure pattern portion 30b are also formed at a constant pitch in the X and Y directions.

As described with reference to FIGS. 2 and 3, the irradiation area LA is irradiated with interference light (interference fringes) L3. The pitch of the interference fringes in the X direction is, for example, that of the fine structure pattern portion 30b. It is determined according to the line width and pattern pitch.

That is, in the X direction on the surface Sa to be processed in FIG. 4, it is divided into a region PT1 in which the fine structure pattern portion 30b is formed and a region PT2 in which the wiring portion 30a having other sparse pattern configuration is formed. As a result, relatively strong scattered light or diffracted light is generated toward the light detection unit 37 while the interference light (interference fringe) L3 is irradiated on the region PT1, and relative light is emitted while the region PT2 is irradiated. Only weakly scattered and diffracted light can be generated.

The configuration of the circuit pattern 30 constituting each pixel (the shape in the XY plane and the concavo-convex structure in the Z direction) is basically the same everywhere, but when viewed in the circuit pattern 30, the shape in the XY plane There is a specific distribution in the fineness and the fineness of the concavo-convex structure. Therefore, at least two detection points located at appropriate intervals among the plurality of pixel configuration patterns (circuit patterns 30) formed in a matrix on the processing surface Sa, the fineness in the circuit pattern 30 is determined. If the distribution (density) is detected, it is possible to measure the positional deviation of the processing surface Sa in the X direction (or Y direction), the inclination in the XY plane, the expansion and contraction in the X direction, and the like. Furthermore, by using three or more detection points, two-dimensional distortion (pixel array distortion) in the XY plane in the region surrounded by the detection points of the processing surface Sa can be measured.

The interference light L3 irradiated to the two irradiation regions LA is transmitted or diffracted according to the shape of the circuit pattern 30 in the pixel of the substrate S (step difference structure, refractive index difference of the pattern material, etc.) Scatter or reflect. Among these, the light component L4 scattered or reflected to the + Z side is guided to the light detection unit 37 by the light guide member. The light detection unit 37 detects the intensity of the light component L4.

The detection result in the light detection unit 37 is, for example, two graphs shown in FIG. These two graphs are graphs showing detection results in each irradiation region LA. The vertical axis of the graph indicates the light intensity of the light component L4, and the horizontal axis of the graph indicates the relative X direction position of the interference light L3 and the substrate S. As shown in the two graphs, for example, in the region PT1 in which the patterns are formed relatively densely, the light intensity of the light component L4 increases. Further, in the region PT2 where the pattern is formed relatively sparsely, the light intensity of the light component L4 becomes small.

On the substrate S, pixel circuit patterns 30 are repeatedly formed in the transport direction (X direction) and are arranged in a line in the Y direction. For this reason, when the substrate S is not deformed or displaced (inclination in the XY plane, etc.), as a detection result in the two position detection units 22, repetition of the same waveform is detected in the same phase. Will be.

On the other hand, for example, when the substrate S is deformed or displaced, changes (distortions) occur in the arrangement and position of the circuit pattern 30 of the pixel in accordance with the deformation or misalignment of the substrate S. For example, when an anisotropic expansion / contraction occurs in the substrate S, the position of the pixel circuit pattern 30 is different with respect to two irradiation areas LA whose positions in the X direction coincide with each other, and two position detections are performed. A phase difference occurs at the peak position of the waveform detected between the portions 22. In an extreme case, the circuit pattern 30 of the pixel included in the region may be slightly deformed due to local wrinkles generated in a part of the substrate S. In such a case, it is also possible to estimate such a situation by measuring the difference in waveform detected by each of the two position detection units 22 and the difference in periodicity (disturbance, etc.).

The calculation unit 23 calculates the deformation amount and the positional deviation amount of the substrate S based on the detection results of the two position detection units 22. The calculation result in the calculation unit 23 is transmitted to the control unit CONT. The control unit CONT adjusts the deformation and displacement of the substrate S using the correction control system 60 based on the calculation result of the calculation unit 23. Further, the control unit CONT changes the posture of the correction mechanism 50 and the position in the X direction and the Y direction based on the calculation result of the calculation unit 23, and the shape of the image projected on the projection area PA, the X direction, and the Y direction. Adjust the position.

The control unit CONT causes such position information to be detected a plurality of times at regular intervals in the transport direction (X direction) of the substrate S. When the deformation or misalignment of the substrate S is detected in the plurality of detections, the control unit CONT uses the correction control system 60 or the correction mechanism 50 in the exposure apparatus EX to determine the shape and position of the substrate S. Then, the shape and position of the image projected on the projection area PA are corrected.

As described above, the transport device 20 according to the present embodiment includes the transport device 20 that transports the belt-shaped substrate S on which the circuit pattern 30 is formed, and the transport direction (X direction) of the substrate S among the circuit patterns 30. ) And a position detection unit 22 that detects at least two irradiation areas LA in a direction (Y direction) intersecting the transport direction a plurality of times, and the detection result of the position detection unit 22 on the substrate S in the transport direction. Since the calculation unit 23 that calculates information related to deformation or displacement and the correction control system 60 that corrects deformation or displacement of the substrate S based on the result calculated by the calculation unit 23 are provided, the substrate S is deformed. Even when a positional deviation occurs, the belt-like substrate S can be transported with high accuracy.

Further, the substrate processing unit 3 according to the present embodiment performs processing on the processing surface Sa on which the circuit pattern 30 is formed among the transport device 20 and the substrate S transported by the transport device 20. The correction control system 60 included in the transfer apparatus 20 includes the processing apparatus 10 that performs the correction, and corrects at least one of deformation or displacement of the processing surface Sa with respect to the processing apparatus 10. The overlay accuracy of the circuit pattern 30 to be formed can be increased.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the circuit pattern 30 is obtained by dividing the slit light L emitted from the illumination system 31 of the position detection unit 22 into two interferences and irradiating the irradiation area LA with interference light (interference fringes) L3. As long as it is a repetitive pattern structure like a pixel, the same measurement is possible by irradiating the interference light L3 from the position detection unit 22 at any part on the surface Sa to be processed. It is. Therefore, the position detectors 22 (irradiation areas LA) may be arranged at three or more locations in the Y direction. Alternatively, the position detection units 22 (irradiation areas LA) may be arranged at a plurality of positions in the X direction that is the feeding direction of the substrate S.

If a plurality of position detectors 22 (irradiation areas LA) are arranged in each of the XY directions, the deformation state of the surface Sa can be sequentially measured in real time while the substrate S is being sent in the X direction.

Further, the width in the X direction (width at which interference fringes are formed) of the irradiation area LA of the interference light L3 in the above embodiment is about the pitch in the X direction of pixels formed on the processing surface Sa (for example, around 300 μm). The pitch of the interference fringes is set to about several μm. However, the present invention is not limited to this, and a single slit light having a width in the X direction of several μm and a length in the Y direction of about several mm is covered. A method of irradiating the processing surface Sa, or irradiating a plurality of such slit lights in the X direction at intervals of the pixel pitch, and photoelectrically scattering light and diffracted light generated from the circuit pattern 30 by irradiation of each slit light. A detection method may be used.

Moreover, in the said embodiment, although the position detection part 22 was set as the structure which detects the light component L4 of the scattered light which advanced to the + Z direction among the interference light L3 irradiated to the irradiation area | region LA, it is not restricted to this. For example, diffracted light (or scattered light) that is diffracted in the irradiation region LA and travels in a direction other than the + Z direction may be detected.

In FIG. 2, the support surface 15 of the substrate stage SST is a flat surface. However, depending on the form of the exposure apparatus EX, the substrate stage SST is constituted by a rotating drum, and the substrate S is wound around the rotating drum and conveyed. The first embodiment can be similarly applied to the form in which the deformation of the substrate Sa (device forming region) is measured and exposed while being wound around the rotating drum.

In the above-described embodiment, the exposure apparatus EX using the projection optical system PL as an exposure apparatus has been described as an example. However, the present invention is not limited to this. For example, a proximity type exposure apparatus, a contact type exposure apparatus, or the like An exposure apparatus may be used.

In the above embodiment, the configuration using the flat mask M as an example of the mask of the exposure apparatus has been described as an example. However, the present invention is not limited to this, and a drum mask formed in a cylindrical shape is used. Also good.

[Second Embodiment]
Next, the configuration and operation of the second embodiment will be described with reference to FIGS. 5 to 7B. In the second embodiment, as shown in FIG. 5A, a plurality of interference fringes projected on the substrate S at predetermined intervals in the Y direction (width direction of the substrate) (the pitch direction of the fringes is the X direction). ) A calibration mechanism is provided for accurately grasping the relative positional relationship between LA1, LA2, and LA3 in advance.

FIG. 5A shows an apparatus configuration viewed in the XY plane, and FIG. 5B shows an apparatus configuration viewed in the XZ plane. In this embodiment, a plurality of pattern regions PT for a display panel of an organic EL display are formed on the substrate S in the transport direction (X direction) of the substrate S with a certain margin region TA interposed therebetween. In this embodiment, it is assumed that the base material of the substrate S is a transparent resin film, an ultrathin glass sheet, or the like, and no light-shielding pattern is formed in the blank area TA.

In FIG. 5A, as in FIG. 2, the substrate S is transported horizontally with a predetermined tension in the X direction by the set of nip rollers 24a and 24b and the set of nip rollers 25a and 25b. In the exposure area Exa set on the substrate S, a plurality of trapezoidal projection areas PA by the multi-lens projection optical system PL are staggered. Under the exposure area Exa of the substrate S, a planar stage SST that supports the substrate S flatly is disposed. FIG. 5 shows a multi-lens method in which four projection optical systems PL are arranged in the Y direction.
In each projection optical system PL, an optical element G2 (hereinafter referred to as an image shifter G2) that finely moves the position of the pattern image of the mask projected in the projection area PA in a range of about ± several μm in the XY direction. There is provided an optical element G1 (hereinafter referred to as a magnification corrector G1) for adjusting the projection magnification of the pattern image of the mask projected in the projection area PA in a range of about ± several tens of ppm.

Three measurement devices FD1 to FD3 that project interference fringes LA1, LA2, and LA3 are provided at three locations separated in the Y direction in front of the exposure region, and the measurement regions by the measurement devices FD1 to FD3 on the substrate S are provided. On the lower side, as shown in FIG. 5 (b), a flat top plate TP elongated in the Y direction, pedestals ST1 and ST2 supporting the top plate TP, a linear motor pedestal ST3 with guide extending in the Y direction, and the linear motor pedestal ST3 And a measurement stage MH that linearly moves in the Y direction.

The measurement stage MH is normally retracted to the extreme end position in the Y direction, but during the calibration operation (calibration), each of the interference fringes LA1, LA2, and LA3 that passes through the blank area TA of the substrate S. Is moved in the Y direction by the linear motor in the lower space of the substrate S so that the light is received by the sensor unit.

6A and 6B show detailed configurations of the linear motor pedestal ST3 with guide and the measurement stage MH. The pedestal ST3 is provided with a linear motor LMG having a lateral guide surface (parallel to the YZ plane) extending linearly in the Y direction. Measurement stage MH is supported by roller bearings or air bearings along the upper surface and lateral guide surface of pedestal ST3, and moves in the Y direction by the thrust of linear motor LMG.

Three sensor units SU1, SU2, and SU3 are provided on the upper surface of the measurement stage MH. The sensor units SU1 and SU2 have the same configuration, and are arranged at an interval in the Y direction such that the sensor units SU1 and SU2 are within the irradiation region of one interference fringe LA1 (or LA2 and LA3). As an example, the sensor units SU1 and SU2 are composed of a glass plate on which a transmission type grating corresponding to the pitch direction of the projected interference fringes LA1 (or LA2 and LA3) is formed, and a photoelectric element embedded below the glass plate. Is done. In addition, the sensor units SU1 and SU2 may be CCD elements that simply image a part of the interference fringes LA1 (or LA2 and LA3).
The third sensor unit SU3 is formed continuously on the outer side of the pattern region PT on the substrate S in the Y direction, etc., at alignment intervals formed at regular intervals in the X direction, or continuously in a thin line shape in the X direction. A line pattern or the like is photoelectrically detected. The alignment mark and line pattern are formed on the upper surface (surface to be processed) or the lower surface of the substrate S in the initial stage of the manufacturing process.

Although the light receiving surfaces of the sensor units SU1 and SU2 are separated in the Y direction, they are located within the irradiation area of one interference fringe LA1 (or LA2 and LA3), so that each signal of the sensor units SU1 and SU2 is received. By analyzing, the residual rotation error component in the XY plane of one interference fringe LA1 (or LA2, LA3) can be found. That is, it can be seen how much the pitch direction of the interference fringes LA1 (or LA2, LA3) is inclined from the X direction.

The residual rotation error in the XY plane of the interference fringes LA1 (or LA2, LA3) may be corrected by slightly rotating the entire measuring device FD1 (or FD2, FD3) in the XY plane, or the measuring device FD1. (Or FD2, FD3) A specific optical element inside may be slightly rotated to correct it.

On the side in the X direction of the measurement stage MH, a ribbon-like wire for supplying power to each sensor unit SU1, SU2, SU3, taking out detection signals, or an air supply tube for an air bearing, etc. A cable bundle WH bundled together is provided.

The linearity of the movement of the measurement stage MH in the Y direction depends on the machining accuracy of the lateral guide surface (parallel to the YZ surface) of the linear motor LMG, but considering the occurrence of yawing and the like, the position of the measurement stage MH in the Y direction Are measured by two laser measurement interferometers RV1 and RV2. Therefore, corner cubes CB1 and CB2 that receive the beam from the laser measurement interferometer are fixedly provided at the end of the measurement stage MH in the Y direction. Since the laser length measurement interferometers RV1 and RV2 may measure only in the Y direction, the two corner cubes CB1 and CB2 may be simple plane mirrors.
The two laser measurement interferometers RV1 and RV2 both measure the position of the measurement stage MH in the Y direction. However, since the corner cubes CB1 and CB2 are separated from each other by ΔXcb in the X direction, If a difference ΔLy occurs in (long amount), it is measured as a yawing component (rotation error in the XY plane of the measurement stage MH) Δθz. That is, the yawing error can be calculated from the relationship sin (Δθz) = ΔLy / ΔXcb.

Further, the average value of the measurement positions of the two laser measurement interferometers RV1 and RV2 is used as the current position of the measurement stage MH, and the thrust of the linear motor LMG is feedback-controlled, thereby precisely moving the measurement stage MH in the Y direction. Or can be positioned at a target position.

As shown in FIG. 6B, the height position Fp in the Z direction of the light receiving surface of each sensor unit SU1, SU2, SU3 is set to be the same as the top surface of the top plate TP shown in FIG. The plate TP is formed with slot-shaped openings corresponding to the movement trajectories of the sensor units SU1, SU2, and SU3. In addition, an infinite number of fine gas ejection holes and suction holes are formed on the upper surface of the top plate TP, and the substrate S thereon is supported by a fluid bearing.

6A and 6B, when the blank area TA of the substrate S is located in the movement locus in the Y direction of the measurement stage MH (sensor units SU1 to SU3), that is, the blank area TA has three interferences. When brought to the projection positions of the fringes LA1 to LA3, the measurement stage MH (sensor units SU1 to SU3) sequentially moves under the projection positions of the three interference fringes LA1 to LA3, and each interference fringe LA1. The residual rotation error of LA3 is measured, and the relative position error in the X direction (pitch direction) of the three interference fringes LA1 to LA3 is measured.
When measuring the relative position error of the interference fringes, the measurement stage MH temporarily stops at the projection position of each of the interference fringes LA1 to LA3, but errors due to the yawing component Δθz of the measurement stage MH occurring at the stationary position occur. Correction is performed based on the measurement results of the laser measurement interferometers RV1 and RV2.

The time for measuring the position of each interference fringe by positioning the measurement stage MH at the projection positions of the three interference fringes LA1 to LA3 is extremely short. As an example, if the measurement time of one interference fringe LA is 0.5 seconds and the time for the measurement stage MH to move to the adjacent interference fringes is 0.8 seconds, the total measurement time is 0.5 seconds × 3 + 0. 8 seconds × 2 = 3.1 seconds. Therefore, if the transport speed of the substrate S is 5 cm / second, the width of the blank area TA in the Y direction may be 16 cm with a margin.

Such a calibration operation by measuring the relative position error of the interference fringes need not be performed in all the blank areas TA on the substrate S. For example, it is performed once every time five or ten pattern areas TP pass. You may make it do. Therefore, as an example, the width of the blank area TP to be calibrated may be 16 cm or more, and the width of the other blank area TP may be about 5 cm, for example.

As described above, using the measuring devices FD1 to FD3 that have been calibrated to obtain the relative positional error of the three interference fringes LA1 to LA3, as described above with reference to FIGS. The distortion (deformation) in the XY plane of the periodic fine pattern structure formed in the pattern region TP is required.
When a pattern image to be superimposed is projected onto the pattern region TP on the substrate S via the projection optical system PL and scanning exposure is performed, local distortion in the pattern region TP measured by the measuring devices FD1 to FD3. Accordingly, by driving the magnification corrector G1 and the image shifter G2 in the projection optical system PL in synchronization with the movement of the substrate S in the Y direction, the overlay accuracy can be greatly improved.

7A, 7B, and 8 show the structures of the measuring apparatuses FD1 to FD3 shown in FIG. 5, and here, the configuration of the measuring apparatus FD1 is shown as a representative.
7A is an arrangement viewed in the XZ plane, FIG. 7B is an arrangement viewed in the YZ plane, and FIG. 8 is an arrangement viewed in the XY plane from the laser light source 100 until splitting into two beam beams. is there.

The laser light source 100 shown in FIG. 8 is composed of, for example, a highly coherent He—Ne laser source having a wavelength of 633 nm, a beam expander optical system, a beam cross-sectional shaping optical system, etc., and a laser beam having a rectangular cross section. Is split by the beam splitter 102, and one transmitted light is incident on the apex angle of the right-angle prism mirror 104.

One of the beams divided into two at the apex angle of the right-angle prism mirror 104 is reflected by the mirror 103a as the beam L1, and is reflected in the Z-axis direction by the reflecting surface of the mirror 106 having the opening 106a formed at the center. The The other of the beams divided at the apex angle of the right-angle prism mirror 104 is reflected by the mirror 103b as a beam L2, and reflected by the reflecting surface of the mirror 106 in the Z-axis direction.

As shown in FIGS. 7A and 7B, the beams L1 and L2 reflected by the mirror 106 each have a negative power in the YZ plane and are incident on cylindrical lenses 108a and 108b which are parallel plates in the XZ plane. Here, the widths of the beams L1 and L2 diverge and expand only in the YZ plane. The beams L1 and L2 have positive power in the YZ plane, pass through cylindrical lenses 110a and 110b, which are parallel flat plates in the XZ plane, and become parallel light with a constant width in the YZ plane. Thereafter, the beams L1 and L2 have negative power in the XZ plane, and the beam width is diffused in the XZ plane by the cylindrical lenses 112a and 112b which are parallel flat plates in the YZ plane, and positive power is generated in the XZ plane. And enters the cylindrical lens 114 which is a parallel plate in the YZ plane.

The beams L1 and L2 emitted from the cylindrical lens 114 toward the substrate S are projected on the substrate S obliquely as parallel light beams inclined at a symmetric angle with respect to the normal of the surface of the substrate S. As a result, periodic interference fringes LA1 (pitch Pf) in the X direction are generated on the substrate S. As an example, the irradiation area of the interference fringe LA1 on the substrate S is set to 20 mm in the Y direction and about 150 μm in the X direction, but the width in the X direction may be smaller than this, and the length in the Y direction is May be longer.

The width of the interference fringe LA1 in the X direction is determined according to the pattern structure (pixel pitch, etc.) on the substrate S as shown in FIG. 4, but the level of the detected photoelectric signal is accompanied by a predetermined strength. The waveform is set to change. In general, in a large screen display (50 inch class), one pixel is 300 to 450 μm square, and the subpixel for each RGB color has a short side of 100 to 150 μm and a long side of 300 to 450 μm.

In the pixel region on the substrate S shown in FIG. 4, since the RGB subpixels (30a, PT2) are arranged in the Y direction, the TFT portion (30b, PT1) for each subpixel is 300 in the X direction. They are arranged at a pitch of ˜450 μm. Although it depends on the structure of the display, the area occupied by the TFT portion (30b, PT1) is smaller than the area for one pixel, for example, 1/3 or less in the X direction as in the case of FIG. Therefore, for example, a TFT portion (30b, PT1) having a dense structure with a line width of 10 μm or less has a width of about 100 μm in the X direction and sandwiches a sub-pixel portion (30a, PT2) of 200 to 350 μm in the X direction. It will be distributed repeatedly.

In the case of such a display structure, the X-direction dimension of the irradiation area of the interference fringes LA (LA1 to LA3) can be about 50 to 150 μm, and the pitch Pf of the interference fringes LA (LA1 to LA3) is several It can be set to μm or less. The pitch Pf of the interference fringes LA (LA1 to LA3) is uniquely determined by the crossing angle and wavelength of the beams L1 and L2 crossing on the substrate S.
When the inclination angle (incident angle) of the beams L1 and L2 with respect to the normal line perpendicular to the surface of the substrate S is ± θf, the pitch Pf of the interference fringes LA (LA1 to LA3) is λ as the wavelength of the beams L1 and L2. It is represented by the following formula (1).
Pf = λ / 2sin (θf) (1)
As an example, when the wavelength λ is 633 nm, in order to set the pitch of the interference fringes Pf to 3 μm, it is sufficient to set sin (θf) ≈0.106, and the incident angle θf is about 6 degrees.

In the present embodiment, the interference fringes LA (LA1 to LA3) are arranged with a plurality of slit lights having a width in the X direction of 1 to several μm and a length in the Y direction of several tens of millimeters at a pitch Pf in the X direction. Works like a thing. That is, if the slit light has a very narrow width in the X direction, a large amount of diffracted / scattered light can be generated from the TFT portion (30b, PT1) having a dense microstructure. By arranging the slit light, more diffracted / scattered light can be generated, and the S / N at the time of signal detection can be improved. Of course, in principle, one slit light may be used.

Of the diffracted / scattered light generated from the substrate S by the irradiation of the interference fringes LA (LA1 to LA3), the diffracted / scattered light L3 generated in the normal direction (Z direction) is the cylindrical lens 114, the cylindrical lens 112c, and the cylindrical lens. 110c passes through the cylindrical lens 108c, passes through the opening 106a of the mirror 106, and reaches the photoelectric sensor 120. The cylindrical lenses 112c, 110c, and 108c are substantially the same as the cylindrical lenses 112a (112b), 110a (110b), and 108a (108b) for transmitting the beam L1 (L2).

The photoelectric sensor 120 collects the entire diffracted / scattered light L3 generated in the Z direction from within the irradiation region of the interference fringes LA (LA1 to LA3), and outputs a signal having a level corresponding to the total light amount.
As the substrate S moves in the X direction at a constant speed with respect to the irradiation area of the interference fringes LA (LA1 to LA3), the photoelectric sensor 120 detects the relative position of the irradiation area as shown in FIG. A signal whose intensity changes according to the change is obtained.

Further, as shown in FIGS. 7A and 7B, when the sensor units SU1 and SU2 are located in the irradiation region of the interference fringes LA (LA1 to LA3) below the substrate S, each photoelectric element in the sensor units SU1 and SU2 is located. Since the sensor can measure the displacement of the interference fringes in the pitch direction (X direction) at two locations in the Y direction within the interference fringes LA (LA1 to LA3), the interference fringes LA (LA1 to LA3) in the XY plane can be measured. Residual rotation error (minor tilt) can be known.

[Third embodiment]
9A and 9B show another configuration example of the measuring device FD1, and instead of forming the interference fringes LA (LA1 to LA3) on the substrate S, one slit light SB extending elongated in the Y direction is shown. The scattered light generated from the substrate S (or the grating on the sensor units SU1 and SU2) by irradiation with the slit light SB is photoelectrically detected by the photoelectric sensors 121 and 122 disposed in the immediate vicinity of the irradiation region. Show.

Here, the slit light SB in which the beam L0 from the laser light source is expanded one-dimensionally in cross-sectional dimensions via a plurality of cylindrical lenses 108d, 110d, 112d, and 114 and is condensed in the short direction (Y direction). And projected onto the substrate S. The width Sf of the slit light SB in the Y direction can be several μm or less.
The photoelectric sensors 121 and 122 are disposed on both sides in the X direction below the cylindrical lens 114 and receive scattered light and diffracted light generated from the irradiation region of the slit light SB on the substrate S. The light receiving surfaces of the photoelectric sensors 121 and 122 may be elongated in the Y direction in accordance with the longitudinal dimension of the slit light SB. Further, as shown in FIG. 9B, the photoelectric sensor 122 may be separated in the Y direction to form three photoelectric sensors 122a, 122b, and 122c.

[Other variations]
Sensor units SU1 and SU2 that receive the interference fringes LA1, LA2, and LA3 projected from the measuring devices FD1 to FD3 are provided on the measurement stage MH shown in FIGS. 6A and 6B, and photoelectric detection is performed. Occurs when only the reflection type diffraction grating (phase grating) is arranged at the position of the upper surface (light receiving surface) of the sensor units SU1 and SU2, and the interference fringes LA1, LA2, and LA3 are projected onto the reflection type diffraction grating. The diffracted / scattered light L3 to be detected may be detected by the photoelectric sensor 120 (FIGS. 7A, 7B, and 8) in the measuring devices FD1 to FD3.
The grating periodic direction of such a reflective diffraction grating is arranged so as to coincide with the periodic direction of the interference fringes LA1, LA2, and LA3. The relationship between the pitch Pf of the interference fringe and the grating pitch of the reflective diffraction grating is 1 : 1 or 2: 1 etc.
An example in which position measurement is performed by irradiating a reflection diffraction grating with interference fringes due to two-beam interference in this way is disclosed in, for example, Japanese Patent No. 2691298.

Further, when a reflection type diffraction grating is provided, the flat plate member on which the grating is formed is microvibrated (frequency fd) with an amplitude of about ½ of the pitch in the grating period direction by a piezoelectric actuator or the like. By detecting the output signal from the modulated photoelectric sensor 120 (120A to 120C) by a synchronous detection circuit or the like, each interference fringe LA1 with reference to the vibration center in the pitch direction of the flat plate member (reflection diffraction grating), The positions in the pitch direction of LA2 and LA3 can be determined accurately.

S ... Substrate CONT ... Control part Sa ... Processed surface EX ... Exposure apparatus L ... Slit light LA ... Irradiation area L1 ... First slit light L2 ... Second slit light L3 ... Interference light L4 ... Light component 2 ... Substrate supply part 3 ... substrate processing unit 4 ... substrate recovery unit 10 ... processing device 20 ... transfer device 21 ... transfer unit 22 ... position detection unit 23 ... calculation unit 30 ... circuit pattern 30a ... wiring unit 50, 60 ... correction control system 100 ... substrate Processing equipment.

Claims (10)

1. A transport unit that transports a belt-like substrate on which a circuit pattern including a repetitive pattern unit having a predetermined period is formed;
   A position detector that outputs a detection signal corresponding to the repetitive pattern portion in the circuit pattern at at least two positions in a direction intersecting the transport direction of the substrate while the substrate is transported by the transport portion; ,
   A calculation device that calculates information on at least one of deformation or displacement of the substrate based on a detection result of the position detector;
   A substrate transfer apparatus comprising: a correction control system that corrects at least one of deformation or displacement of the substrate based on a result calculated by the calculation device.
2. The position detector is
   A light irradiating unit for irradiating detection light to the at least two positions of the circuit pattern;
   A light detection unit that detects at least one of scattered light and diffracted light generated at the at least two positions by irradiation of the detection light;
   The substrate transfer device according to claim 1, wherein the calculation device calculates the information based on a detection result of the light detection unit.
3. The substrate transport apparatus according to claim 2, wherein the detection light includes at least one slit light that extends in a direction intersecting the transport direction and includes at least two positions of the circuit pattern.
4. The substrate transport apparatus according to claim 2, wherein the light irradiation unit includes a coherent light source that projects interference fringes generated at a predetermined pitch in the transport direction as the detection light.
5. The substrate transfer apparatus according to any one of claims 1 to 4,
   A processing unit that performs processing on a processing surface on which the circuit pattern is formed, of the substrate transported by the substrate transporting device;
   The said control system with which the said board | substrate conveyance apparatus is provided correct | amends at least one of the deformation | transformation or position shift of the said to-be-processed surface in the process area | region by the said process part.
6. The substrate processing apparatus according to claim 5, wherein the position detector detects the positions of the at least two positions in the circuit pattern on the upstream side of the processing unit with respect to the substrate transport direction.
7. The substrate processing apparatus according to claim 5, wherein the processing unit performs an exposure process on the processing target surface.
8. The processing unit includes an optical system that irradiates exposure light to a plurality of positions patterned in a local region of the processing surface of the substrate, and is patterned based on a result calculated by the calculation device. The substrate processing apparatus according to claim 7, further comprising a correction mechanism that corrects an irradiation state of the exposure light.
9. The substrate processing apparatus according to claim 5, wherein the processing unit further includes a substrate support unit that supports a back surface of a surface to be processed of the substrate.
10. The substrate processing apparatus according to claim 9, wherein the substrate support unit has a flat support surface.

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