JPH1020478A - Aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a work of removing foreign matter from a mask without manually pulling out the mask. SOLUTION: A chamber 60 for removing the foreign matter from the mask is installed in the aligner main body, and the mask M decided by a foreign matter inspecting part as a mask where the foreign matter affecting a pattern transfer sticks is automatically carried to the foreign matter removing chamber by a mask carrying system 8 installed in the main body. The foreign matter is removed by ejecting air through an air gun 68. In order to prevent the suspended foreign matter which is removed from the mask from contaminating the inside of the aligner main body and also to prevent the matter from sticking to the mask again, the foreign matter removing chamber is separated from other spaces in the aligner by partition walls 61a, 61b and 61c, and down flow 66 is generated by clean air. A map display device 80 for displaying the foreign matter detection result is installed near the foreign matter removing chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for transferring a pattern formed on a mask to a photosensitive substrate, and more particularly, to an exposure apparatus capable of removing foreign substances attached to a mask.

[0002]

2. Description of the Related Art In a lithography process for manufacturing a semiconductor device or a liquid crystal display device, a device pattern formed on a reticle or a photomask (hereinafter, referred to as a mask) is formed by a semiconductor wafer or a glass plate coated with a photosensitive agent such as a photoresist. An exposure apparatus is used as an apparatus for transferring a high-resolution image onto a photosensitive substrate.

FIG. 8 is a conceptual diagram showing the entire structure of a conventional exposure apparatus. FIG. 8 (a) is a top view and FIG. 8 (b) is a front view. The exposure apparatus mainly includes an apparatus main body 1, a console 2,
It is composed of a control rack 3. The apparatus main body 1 includes a chamber 5 in which the temperature is adjusted. Inside the chamber 5, a projection optical system PL for transferring the pattern of the mask M onto the photosensitive substrate PT, and for exchanging a plurality of masks M at high speed. A mask changer MC, an XY stage ST for mounting the photosensitive substrate PT and moving in the X and Y directions, a mask library ML for storing a large number of masks M, and a foreign substance inspection for inspecting foreign substances on the mask M A part 6 and the like are provided.

If foreign matter such as dust adheres to the mask M, an image of the foreign matter is transferred to the photosensitive substrate PT and appears as a pattern defect. In particular, when exposing each shot area on the photosensitive substrate by the step-and-repeat method,
A common defect occurs in all shot areas on the photosensitive substrate PT. The mask is separated from the surface of the mask by a certain distance (for example, a few mm) to prevent foreign substances from adhering to the surface, and is a thin film called a pellicle (foreign substance adhesion preventing film).
It is also being carried out. When pattern transfer is performed using a mask with a pellicle, foreign matter adhering to the surface of the pellicle is not transferred as a foreign matter image is not focused on the surface of the photosensitive substrate. However, when the foreign matter adhering to the pellicle surface is relatively large, exposure unevenness may occur on the photosensitive substrate surface. Therefore,
Even in the case of using a mask with a pellicle, it is necessary to inspect the size and position of the foreign matter attached to the pellicle, and to remove the foreign matter if it interferes with pattern exposure.
The foreign matter inspection section 6 is for inspecting whether foreign matter is attached to the surface of the mask M or the surface of the pellicle.

An arrow in FIG. 8A indicates a mask transport path in the exposure apparatus main body 1 by a mask transport system. Prior to the start of exposure, the mask M is taken out of the mask library ML by a mask loader of a mask transport system.
It is conveyed to the foreign substance inspection unit 6 (arrow in the figure). The foreign matter inspection unit 6 inspects the presence or absence of foreign matter on the mask M and the pellicle, and according to the size of the detected foreign matter, displays a CR on the console 2.
The result is output on T7. If it is determined that the size of the detected foreign matter does not affect the pattern transfer, the mask M
Is transported to the mask changer MC and mounted at a predetermined position on the mask changer MC (arrow). When all of the predetermined masks (four in the illustrated example) are mounted on the mask changer MC, the exposure operation starts. On the other hand, when it is determined that the size of the foreign matter detected by the foreign matter inspection unit 6 affects the transfer of the pattern, a map display showing the size and position of the foreign matter is performed on the CRT 7 and the mask library ML is displayed in the mask library ML. Return the mask M (arrow).

When the operator knows from the display on the CRT 7 of the console 2 that there is a mask M returned to the mask library ML due to foreign matter adhesion, the returned mask M is taken out of the mask library ML and set in a cleaning machine. The foreign matter on the mask or the pellicle is removed by air blowing or the air is blown back to the mask library ML. Then, the foreign substance inspection unit 6
, A foreign substance inspection and a foreign substance removing operation are repeated until there is no foreign substance affecting pattern transfer.

[0007]

The above-described conventional foreign matter removing method has the following problems. First, the mask, which is determined by the inspection by the foreign matter inspection unit to need to remove foreign matter, is manually taken out of the exposure apparatus main body, and is manually returned to the inside of the apparatus main body after the foreign matter removing operation. Removal work is troublesome, and there is a great risk that foreign matter will adhere again after foreign matter is removed.

[0008] Further, the adhered foreign matter is usually several μm to several hundred μm.
m is very small, so a foreign matter removal work requires a map showing the place where foreign matter is attached.
Perform the removal work while holding the mask in front of T while checking the place where the foreign matter is attached, or print out the map,
It is necessary to perform a removal operation based on the output.

Further, the removal of the mask manually
There is a risk of damaging expensive masks. For example, a mask for manufacturing a liquid crystal display element is 500 mm × 400 mm.
, The weight of the mask also increases, making it virtually impossible to remove the mask manually.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide an exposure apparatus capable of removing foreign substances from a mask without manually removing the mask. . Another object of the present invention is to provide an exposure apparatus capable of automatically removing foreign substances from a mask without manual intervention.

[0011]

According to the present invention, a foreign matter removing chamber for a mask is provided in a main body of an exposure apparatus, and a mask which is judged by a foreign matter inspection section to have foreign matter affecting pattern transfer is attached to the main body. The object is achieved by automatically transporting the wafer to the foreign matter removal chamber by using the inside of the mask transport system.

That is, the present invention provides an exposure system including a projection optical system for projecting light transmitted through a mask on which a pattern is formed onto a photosensitive substrate, and a foreign matter inspection unit for detecting foreign matter attached to the mask prior to projection. The apparatus is characterized in that a foreign substance removing chamber for removing foreign substances is provided. The removal of foreign matter such as dust in the foreign matter removal chamber can be performed, for example, by blowing air on the mask.

In order to prevent foreign matter removed from the mask in the foreign matter removing chamber from floating in the other space of the apparatus main body and contaminating the inside of the apparatus main body, the foreign matter removing chamber and the other space of the exposure apparatus are separated from each other by a partition wall or the like. Must be isolated by the isolation member.

Further, the foreign matter removing chamber is provided with a clean air supply unit and a clean air supplying unit so that the foreign matter detached from the mask does not adhere to the mask again or scatter from the foreign matter removing chamber to other places. It is desirable. A downflow by clean air is generated in the foreign matter removal chamber, and foreign matter such as dust removed from the mask is captured and collected by flowing in the flow of clean air. Can be avoided. The temperature of the clean air is controlled by the temperature control means, or the air from the temperature controller of the apparatus main body is introduced into the clean air supply unit, so that the temperature of the clean air is the same as the temperature of the air circulating in the apparatus main body. It is preferable to control the temperature difference to be within ± 0.1 ° C.

When foreign matter is removed manually, the foreign matter removing chamber is located near a display device (map display) for displaying the result of foreign matter detection by the foreign matter inspection unit for convenience of confirming the position of foreign matter adhering to the mask. It is good to provide in.

According to the present invention, the foreign substance removing chamber is provided in the exposure apparatus main body in the vicinity of the display device for displaying the adhesion position of the foreign substance, so that the mask is transported to the foreign substance removing chamber by using the transport system of the apparatus main body. The mask does not need to be manually taken out of the apparatus when removing foreign matter. Therefore,
The mask can be prevented from being damaged due to an operation error, and contamination due to reattachment of foreign matter can also be prevented. Further, since there is no need to manually handle the mask, there is no restriction on the size and weight of the mask, and foreign matter removal from a large mask becomes easy.

Further, by providing air blowing means movable by a motor or the like in the foreign matter removing chamber and providing control means for controlling the position of the air blowing means based on the inspection result in the foreign matter inspection section, foreign matter inspection and inspection of the mask can be performed. Foreign matter removal can be automated.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram illustrating one embodiment of an exposure apparatus according to the present invention. The figure is a front view, which schematically shows the inside of an operation console 2 having a display unit 7 such as a CRT and an apparatus main body 1 having a temperature-controlled chamber 5. The apparatus main body 1 is provided with a mask library ML for storing a large number of masks M, a foreign substance removing unit 60 and a map display 80 for displaying inspection results in the foreign substance removing unit 60 and the foreign substance inspecting unit. In a chamber 5 of the apparatus main body 1, a mask changer and a photosensitive substrate
Dimensionally moving substrate stage, illumination optical system for illuminating mask, driving system for mask changer and substrate stage, substrate transport system for transporting photosensitive substrate, mask transport system for transporting mask, and for aligning mask and photosensitive substrate Although an alignment system and a measuring unit such as a laser interferometer for measuring the position of the substrate stage are also provided, they are not shown for simplicity.

The mask transport system has the same configuration as the conventional one having a transport arm capable of vacuum-sucking the mask M. The mask transport system is provided between the mask library ML, the mask changer, the foreign substance inspection unit 6 and the foreign substance removal chamber 60. M can be transported. 2 and 3 are diagrams illustrating an example of a method for inspecting foreign matter adhering to a mask in a foreign matter inspection unit. FIG. 2 is a schematic diagram of an inspection optical system, and FIG. 3 is a schematic diagram of a signal processing system.

It is assumed that the surface of the mask M to be inspected is on the xy plane of the orthogonal coordinate system xyz shown in the figure. The laser beam 10 is condensed by a condensing lens 11, and scans the mask M in the x direction by a scanner 12. At this time, the scanning laser beam 10 is obliquely incident on the surface of the mask M (for example, at an incident angle of 70 ° to 80 °). The scanning position of the laser beam 10 scanned by the scanner 12 is detected by the photoelectric elements 22 and 23. On the other hand, the mask M is mounted on a mounting table 49 and can be moved by a moving means 50 such as a motor in a direction 24 substantially orthogonal to the scanning direction of the laser beam 10, and scans the irradiation unit in the y direction. The mounting table 49 is provided with a suitable movement amount measuring means, for example, a linear encoder 51, and can measure the irradiation position of the laser beam 10 on the mask M in the y direction based on the measured value.

The photoelectric elements 19, 20, and 21 are arranged to receive scattered light from the irradiation units 13 to 15 by the laser light 10 from different directions. Each of the light receiving surfaces of the photoelectric elements 19, 20, and 21 has a condensing lens 16,
The scattered light is condensed by 17 and 18. Further, the optical axis of each of the condenser lenses 16, 17, and 18 is inclined with respect to the surface of the mask M, that is, the x-plane, so that the pattern surface of the mask M is not easily affected by irregular reflection or the like. It is arranged to become. Photoelectric element 19,
Reference numerals 20 and 21 are arranged at an equal distance from a substantially central portion 14 of the scanning of the laser beam 10.

While the laser beam 10 is scanned by the scanner 12, the mask M is moved in the y direction on the xy plane. During this operation, when the laser light 10 irradiates the edge of the pattern formed on the mask M, the scattered light has strong directivity. Therefore, the photoelectric device 1 capable of detecting scattered light from different directions
Only the specific photoelectric element among 9, 20, and 21 receives the scattered light from the edge. Therefore, the arrangement of each photoelectric element is
It is determined that scattered light from the edge of the pattern is not received at the same time. Further, when the laser beam 10 irradiates a foreign substance during scanning, scattered light due to the foreign substance is generated in all directions, that is, almost omnidirectional. Therefore, in this case, all of the photoelectric elements 19, 20, and 21 receive the scattered light from the foreign matter. Further, when there is a foreign matter near the edge of the pattern, scattered light from the edge is received by a specific photoelectric element,
Further, the scattered light from the foreign matter is received by all the photoelectric elements.
At this time, the photoelectric output signal of each photoelectric element has a different value depending on the incident angle with respect to the edge (or with respect to the surface) of the laser beam 10, the size of the foreign matter, and the like.

Therefore, the photoelectric output signals of the photoelectric elements 19, 20, and 21 are appropriately amplified by an amplifier, and the output signals are compared with a predetermined reference signal by a comparator. It is detected whether or not scattered light is generated in the direction of the element. The signal processing for this will be described with reference to FIG.

The photoelectric signals of the photoelectric elements 19, 20, 21 are:
The signals are amplified by amplifiers 30, 31, and 32, respectively.
The output signals of the amplifiers 30, 31, and 32 are subtracted from the reference signal 33 by differential amplifiers 34, 35, and 36, respectively. The logic circuit 37 performs a predetermined logical operation, for example, a logical product operation from the output of each differential amplifier. Therefore, as described above, when all the photoelectric elements output a sufficient photoelectric signal, the logic circuit 37 outputs a predetermined detection signal. That is, the detection signal is output only when the foreign matter on the mask M is irradiated with the laser beam 10. The position of the foreign matter on the mask M is obtained based on the detection signal, the measurement value by the movement amount measuring unit 51, and the scanning position information of the laser beam 10 by the photoelectric elements 22 and 23.

When the photoelectric signal of the photoelectric element 22 is maximized by the counting means 43, a start signal 42 is generated to start counting of a predetermined reference pulse, and stopped when the photoelectric signal of the photoelectric element 23 is maximized. A signal 44 is generated to stop counting. Then, the number of pulses counted in this period is calculated by an appropriate calculating means to determine the position of the spot by the laser beam 10 on the mask M (the position in the x direction on the xy plane). In addition, the magnitude of each of the photoelectric signals of the three photoelectric elements 19, 20, and 21 differs depending on the position of the foreign matter on the mask M. For example, in FIG. 2, when a foreign substance is present in the vicinity of the irradiation unit 13, the photoelectric signal of the photoelectric element 19 is the largest, the photoelectric signal of the photoelectric element 20 is the largest, and the photoelectric signal of the photoelectric element 21 is the smallest. Therefore, when the position of the foreign matter is determined based on each photoelectric signal, the magnitude of each signal according to the position of the foreign matter is corrected.

To this end, amplification converters 38, 39, 40 are provided after the amplifiers 30, 31, 32, respectively. The controller 41 sends the time-sequential sequential signal 4 to the converters 38, 39, 40 from the input point of the start signal 42 described above.
5 is output. This sequential signal 45 is, for example,
Each time a single scanning period of the laser beam 10 is equally divided,
It is a signal that generates a pulse. Converter 38,3
Reference numerals 9 and 40 simultaneously change the amplification degrees of the amplification degree converters 38, 39 and 40 in time series by the input of the sequential signal 45.

In this way, the signal from the foreign matter that has undergone the predetermined correction statistically produces a signal that depends only on the size, regardless of the position of the foreign matter. That is,
Based on the corrected signal values (such as the output signals of the converters 38, 39, and 40), the data may be collated with data on the size of the foreign matter that has been statistically obtained in advance.

As described above, the three photoelectric elements 19, 2
The approximate size of the foreign matter can be obtained simultaneously with the foreign matter detection from the photoelectric signals 0 and 21. In order to simultaneously inspect the back surface of the plate-shaped mask M, the laser beam 10 may be divided using a beam splitter or the like, and may be obliquely incident on the back surface. At this time, in order to detect the scattered light from the foreign matter on the back surface, a plurality of photoelectric elements are further arranged like those on the front surface.

The result of the inspection by the foreign substance inspection section 6 is displayed on the display section 7 of the console 2. As a result of the inspection, the mask M, which has been confirmed to be free of foreign matter, is carried out of the foreign matter inspection unit 6 by the mask transport system, transported to the mask changer as it is, and loaded into a predetermined position on the mask changer in the same manner as before. Is done. As a result of the inspection by the foreign matter inspection unit 6, when a foreign matter that is determined to affect the transfer of the pattern is detected, the mask is transported from the foreign matter inspection unit 6 to the foreign matter removal chamber 60 by the mask transport system. The size and position of the detected foreign matter are graphically displayed on a map display 80 provided adjacent to the display unit 7 of the console 2 and the foreign matter removal chamber 60.

The map display 80 may be a display such as a CRT or a display having LEDs or the like arranged in a matrix. On the map display 80, the foreign matter information on the front side of the mask M and the foreign matter information on the back side of the mask M are displayed simultaneously or switchably. In addition, the sizes of the foreign substances are ranked in several stages, and are distinguished and displayed by, for example, color coding.

FIG. 4 is a view for explaining the schematic configuration of the foreign substance removing chamber and the state of the foreign substance removing operation by the worker. The front surface of the foreign matter removing chamber 60 is opened, and the side walls 61a and 61
It is surrounded by b and 61c to be isolated from other parts of the chamber 5. A door is provided in the front opening, and a foreign substance removal chamber 6 is provided.
When 0 is not used, the opening may be closed. An HEPA filter (High Efficiency Particulate Air Filter) 62 for dust removal is provided above the foreign matter removal chamber 60.
And a fan 63 are attached so that clean air is blown downward. A suction unit 64 is provided at a lower portion, and a downflow 66 by clean air is formed in the foreign matter removing chamber 60. I have. In addition, the side wall 61 of the foreign matter removal chamber 60 facing the opening portion.
The mask M, which is determined by the inspection by the foreign matter inspection unit 6 to need to remove foreign matter, is passed through the opening 65 while being held by the mask loader 8 of the mask transport system. It is carried into the foreign matter removal chamber 60,
It is left at a predetermined position.

A map display 8 is provided near the foreign substance removing chamber 60.
0 is set, and the size and position of foreign matter such as dust are displayed as a map. The operator 82 inserts the air gun 18 into the foreign matter removing chamber 60 from the open front, and clean air or clean N ₂ from the air gun 68 to the foreign matter adhering position on the mask based on the map information displayed on the map display. Foreign matter on the mask M or the pellicle is removed by a method such as air blow which blows gas or the like.

According to this embodiment, the mask M requiring the foreign matter removing operation is the mask loader 8 of the mask transport system.
Thus, the mask M is automatically conveyed into the foreign matter removing chamber 60, and the operator does not need to handle the mask M by hand. Therefore, the foreign matter removing operation can be simplified, and the risk of damaging an expensive mask can be avoided. In addition, since the map display 80 is installed near the foreign substance removal chamber 60 and the foreign substance adhering position on the mask M can be easily confirmed, the work load on the operator can be greatly reduced.

The foreign substance removing chamber 60 is isolated from other spaces in the chamber 5, such as the projection optical system, by partitions 61a, 61b, and 61c except for a minimum opening 65 necessary for transporting the mask to the foreign substance removing chamber 60. Therefore, the foreign matter does not scatter from the foreign matter removal chamber 60 and contaminate other parts of the apparatus main body 1. Further, a downflow 66 by clean air is formed in the foreign matter removing chamber 60, and foreign matter separated from the mask M by air blow or the like by an air gun 68 is collected by the suction unit 64, adhered to a filter or the like, and fixed. Mask M
The foreign matter separated from the mask M does not adhere to the mask M again or scatter to other places.

The mask M processed in the foreign substance removal chamber 60 is
The wafer is transported again by the mask transport system of the apparatus main body 1 to the foreign matter inspection section 6 while being vacuum-sucked and held by the mask loader 8, and is inspected again. As a result of the inspection, if it is confirmed that no foreign matter is attached, the mask M is transferred to the mask changer by the mask transfer system, and is loaded at a predetermined position of the mask changer. As a result of the re-inspection, the mask M in which the foreign matter is still detected is transported again to the foreign matter removing chamber 60 by the mask transport system, and the worker 82 repeats the foreign matter removing operation.

The foreign matter adhering to the mask M is removed from the foreign matter removing chamber 60.
In order to immediately shift to the exposure operation after the mask M is loaded on the mask changer, the temperature of the mask M is adjusted by the temperature controller for adjusting the temperature inside the chamber 5 at the time when the mask M is loaded on the mask changer. It must be at the specified temperature. Therefore, the temperature in the chamber 5 and the temperature in the foreign matter removal chamber 60 need to be the same, and the temperature of the air blown from the fan 63 is controlled to the same temperature as the air in the chamber 5 by the temperature control means. Alternatively, a part of the air blown out from the air outlet of the temperature controller for adjusting the temperature of the atmosphere in the chamber 5 of the apparatus main body 1 is guided to the upper part of the foreign matter removing chamber 60 by a duct, so that the temperature inside the foreign matter removing chamber 60 is reduced. The temperature in the chamber 5 may be the same.

FIG. 5 is a conceptual diagram for explaining another embodiment of the exposure apparatus according to the present invention. FIG. 5A is a top view showing an arrangement of each part in a chamber of the apparatus main body, and FIG. 5B is a front view thereof. The exposure apparatus described here is a scanning batch exposure apparatus using a large mask. In the figure, an illumination system IL for illuminating a partial area of the mask with exposure light, and the optical axis is horizontal (in the Y direction in the figure) (Parallel), a projection optical system PL, a carriage CR that can hold the mask M and the photosensitive substrate PT and can be moved in the direction of arrow B, a mask library ML that stores a plurality of masks M, and foreign matter inspection of the mask M. Only the foreign matter inspection section 6a, a map display 80 for displaying a map of the foreign matter inspection result, and a foreign matter removal chamber 70 for removing foreign matter from the mask are shown. The carriage CR
Is at the exposure start position in FIG. 5A, and is at the mask loading position in FIG. 5B.

The carriage CR includes a mask M and a photosensitive substrate P.
By holding T vertically (parallel to the Z direction) and scanning the projection optical system PL and the illumination system IL fixed in the chamber 5a in the X direction as indicated by arrows, the pattern on the mask M is changed. The image is sequentially transferred onto the photosensitive substrate PT. Further, the apparatus main body 1a is provided with a mask transport system having a mask loader capable of vacuum-sucking and fixing the mask M. The mask transport system includes a mask library ML, a mask changer, a foreign substance inspection unit 6a, and a foreign substance removal chamber 70. The mask M can be transported in between.

In the foreign matter inspection section 6a, in the same manner as described with reference to FIGS.
Foreign matter such as dust attached to the pellicle that protects the pattern surface is detected. However, in this example, the mask M moves while being held vertically, and the optical scanning is performed in the vertical direction.

An HEP for dust removal is provided above the foreign matter removal chamber 70.
An A filter 62a and a fan 63a are attached, and a suction unit 64a is installed below. HEPA
The clean air that has been dust-removed through the filter 62a is blown downward, and is sucked from the suction unit 64a, so that a downflow by clean air is formed in the foreign matter removing chamber 70. A map display 80 is installed near the foreign substance removing chamber 70 at a position where an operator during the foreign substance removing operation can observe.

The arrow in FIG. 5B indicates the transport path of the mask M by the mask transport system in the apparatus main body 1a. Prior to the start of exposure, the mask M is vacuum-sucked and held by a mask loader of a mask transport system, taken out of the mask library ML, and transported to the foreign substance inspection unit 6a (arrow in the figure). The foreign matter inspection unit 6a inspects the surface of the mask M and the presence or absence of foreign matter on the pellicle. If the inspection shows that foreign matter having a size that is problematic for pattern transfer is not detected, the mask M is moved by the mask transport system. It is conveyed to the carriage CR (arrow), and is mounted on the mask stage of the carriage CR.

As a result of the inspection by the foreign matter inspection section 6a, when it is found that foreign matter which is problematic for pattern transfer is attached, the mask M is transferred to the foreign matter removing chamber 70 while being held by vacuum suction by the mask loader. It is carried in (arrow).
At this time, the position and size of the detected foreign matter are displayed on a map on a map display 80 provided near the foreign matter removing chamber 70. After the foreign substance removal operation in the foreign substance removal chamber 70 by the operator, the mask M from which the foreign substance has been removed is carried into the foreign substance inspection unit 6a by the mask transport system, and the foreign substance inspection is performed again (arrow). As a result of this foreign matter inspection, if there is no problem, the wafer is conveyed to the position of the carriage CR by the mask conveying system and mounted on the mask stage of the carriage CR (arrow). When a foreign substance is detected by the foreign substance inspection again, the foreign substance is transferred to the foreign substance removing chamber 70 again and the foreign substance removing operation is repeated.

FIG. 6 is a diagram for explaining the schematic configuration of the foreign substance removing chamber and the state of the foreign substance removing operation by the operator. The foreign matter removal chamber 70 is surrounded by a partition wall and is isolated from the other parts of the chamber 5a except that one surface (in the illustrated A direction) is open so that the worker 82 can access the foreign matter removal chamber. Foreign matter such as dust is prevented from being scattered from 70. A vertically long slit-like opening 75 is provided on a wall surface of the foreign matter removing chamber 70 facing the open portion. Foreign matter inspection section 6
The mask M for which the attachment of foreign matter is detected in a is carried into the foreign matter removal chamber 70 from the opening 75 while being held by the mask loader 8a of the mask transport system. A door may be provided in the open part of the foreign substance removing chamber 70 so that the open part can be closed by the door when the foreign substance removing chamber 70 is not used.

A downflow by clean air is formed in the foreign matter removing chamber 70, and the operator 82 confirms the foreign matter attaching position based on the display of the map display 80 installed near the foreign matter removing chamber 70. Then, an air gun 68 or the like is inserted into the foreign substance removing chamber 70 from the open portion, and the foreign substance removing operation is performed by blowing air to the surface of the mask M or the foreign substance adhering position of the pellicle.

According to this embodiment, the mask M requiring the foreign matter removing operation is the mask loader 8 of the mask transport system.
a, is vacuum-adsorbed and held, and is automatically conveyed to the foreign matter removing chamber 70 and is left standing in a predetermined posture, so that the foreign matter removing operation for the large and heavy mask M is simplified.

In the embodiment described so far, the worker removes foreign matter. Hereinafter, an embodiment will be described in which a foreign substance removing operation is automatically performed using the inspection result of the foreign substance inspection unit, that is, the foreign substance attachment position information.

When a worker removes foreign matter from the mask, one end of the foreign matter removal chamber needs to be open so that the worker can access the mask. Therefore, the setting place of the foreign matter removal chamber is also near the outer wall of the chamber,
In addition, there is a restriction on the arrangement that the operator must be installed at a height at which the worker can easily work. On the other hand, when performing the foreign matter removal work automatically, there is no need to consider the access of the worker, so there is no need for an open part, and there is no restriction on the height position, so any place including the inside of the chamber is included. A foreign substance removal chamber can be installed in the room.

FIG. 7 is a view for explaining an embodiment in which a mechanism capable of automatically performing foreign matter removal is provided in the foreign matter removal chamber. The foreign matter removing chamber 90 is isolated from other spaces in the chamber by surrounding all directions with partition walls, and a slit-shaped opening 95 for allowing the mask M to enter and exit only on one wall surface 91 is provided. . The mask M, on which the adhesion of the foreign matter is detected, is vacuum-sucked and held by the mask loader 8b of the mask transport system in the apparatus main body, and inserted into the foreign matter removing chamber 90 through the slit-shaped opening 95.

In the foreign matter removing chamber 90, a pair of air nozzles 92a and 92b for the front surface and the back surface of the mask M are orthogonal to the direction of movement of the mask (X direction in the illustrated example) (Z in the illustrated example). Direction). A pair of air nozzles 92a and 92b are respectively provided with lead screws 93a and 93, respectively.
3B, the lead screws 93a and 93b are rotationally driven by drive motors 94a and 94b, so that the mask M can be positioned independently in the Z direction orthogonal to the moving direction (X direction) of the mask M. Each nozzle 9
The Z-direction positions of 2a and 92b are determined by drive motors 94a and 94b.
b can be known from the outputs of the encoders 96a and 96b attached to the b. Further, the position of the mask M in the X direction can be known by an encoder or the like provided in the mask driving system. The control system controls the mask transport system and the drive motors 94a and 94b based on the inspection result of the foreign matter inspection unit, controls the position of the air nozzles 92a and 92b in the Z direction while driving the mask M in the X direction, and attaches foreign matter. By blowing clean air to the position from the air nozzles 92a and 92b, foreign matter attached to the mask or pellicle is automatically removed.

By automatically executing the process up to the removal of foreign matter as in this embodiment, there is no danger of foreign matter adhesion due to the intervention of an operator, and it is possible to extremely efficiently remove foreign matter from the mask. Becomes In order to effectively use the limited space in the chamber, it is also useful to use the foreign matter removal chamber as the space for the foreign matter inspection unit.

[0051]

According to the present invention, at the time of removing foreign matter adhering to the mask, the work can be performed while confirming the position of the foreign matter adhering on the inspection map without taking the mask out of the apparatus main body. Work load can be reduced and the work efficiency can be improved. Further, since it is not necessary for an operator to handle the mask by a person, damage to the mask due to an operation error can be prevented, and recontamination of the mask after cleaning can be prevented. In addition, a foreign matter removing operation can be performed even on a large mask.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a first embodiment of an exposure apparatus according to the present invention.

FIG. 2 is a schematic diagram of an inspection optical system in a foreign substance inspection unit.

FIG. 3 is a schematic diagram of a signal processing system in a foreign substance inspection unit.

FIG. 4 is a diagram illustrating a schematic configuration of a foreign substance removing chamber and a state of a foreign substance removing operation performed by an operator.

FIGS. 5A and 5B are conceptual views illustrating another embodiment of the exposure apparatus according to the present invention, wherein FIG. 5A is a top view showing the arrangement of each part in a chamber of the apparatus main body, and FIG.

FIG. 6 is a diagram illustrating a schematic configuration of a foreign substance removing chamber and a state of a foreign substance removing operation performed by an operator.

FIG. 7 is a diagram illustrating an embodiment in which a mechanism capable of automatically performing foreign matter removal is provided in a foreign matter removal chamber.

8A and 8B are conceptual views showing the entire configuration of a conventional exposure apparatus, wherein FIG. 8A is a top view and FIG. 8B is a front view.

[Explanation of symbols]

1, 1a: exposure apparatus main body, 2: console, 3: control rack, 5, 5a: chamber, 6, 6a: foreign matter inspection section, 7
... Display unit, 8, 8a, 8b ... Mask loader, 12 ... Scanner, 19, 20, 21, 22, 23 ... Photoelectric element, 6
0: Foreign matter removal chamber, 62, 62a: HEPA filter,
63, 63a ... fan, 64, 64a ... suction unit,
65 ... opening, 66 ... downflow, 68 ... air gun,
70: foreign matter removal chamber, 75: opening, 80: map display,
90: foreign matter removal chamber, 92a, 92b: air nozzle, 9
3a, 93b: lead screw, 94a, 94b: drive motor, 95: opening, 96a, 96b: encoder, CR ...
Carriage, IL: illumination system, M: mask, MC: mask changer, ML: mask library, PL: projection optical system, PT: photosensitive substrate, ST: XY stage

Claims (7)

[Claims] 1. An exposure apparatus comprising: a projection optical system that projects light transmitted through a mask on which a pattern is formed onto a photosensitive substrate; and a foreign matter inspection unit that detects foreign matter attached to the mask prior to the projection. An exposure apparatus, comprising: a foreign matter removing chamber for removing the foreign matter. 2. The method of removing foreign matter in the foreign matter removing chamber,
2. The exposure apparatus according to claim 1, wherein the exposure is performed by blowing air onto the mask. 3. The exposure apparatus according to claim 1, further comprising an isolation member for isolating the foreign substance removal chamber from another space of the exposure apparatus. 4. The exposure apparatus according to claim 1, wherein the foreign matter removal chamber includes a supply unit and a discharge unit for clean air. 5. A temperature control means for controlling a temperature of the foreign matter removing chamber to a predetermined temperature.
Exposure apparatus according to the above. 6. The foreign matter inspection unit according to claim 1, further comprising a display device for displaying a result of foreign matter detection, wherein the foreign matter removal chamber is provided near the display device. 2. The exposure apparatus according to claim 1. 7. A method according to claim 1, further comprising: a movable air blowing means provided in the foreign matter removing chamber; and a control means for controlling a position of the air blowing means based on an inspection result in the foreign matter inspection unit. An exposure apparatus according to claim 1.