JPH0473775B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an apparatus for automatically cleaning flat substrates, particularly glass substrates such as photomasks and reticles used in the manufacture of semiconductor devices.

(Background of the invention) In the manufacturing process of semiconductor devices such as ICs and LSIs,
If foreign matter adheres to the photomask or reticle, it will be transferred onto the wafer during exposure, reducing the yield of IC manufacturing. For this reason, it takes a lot of time to clean photomasks and reticles to remove attached foreign matter and then inspect whether the foreign matter has been completely removed. By the way, when cleaning a photomask or reticle, if you manually handle the photomask or reticle, no matter how clean it is,
There was a problem in that there was a high possibility that foreign matter from the human body would re-adhere, and that a satisfactory result could not be obtained even though it took a lot of time.

Therefore, various types of cleaning devices are currently being considered that automatically take out the reticle, clean it, and then return it to its original location without any manual intervention. However, even with this type of device, it is difficult to set the reticle on the device,
When removing it from the device, it had to be done manually, and there was still the possibility of foreign matter adhering to it. Furthermore, if a visual inspection is performed to inspect a reticle after cleaning, a large amount of time is spent on the inspection, and the efficiency of obtaining a completely cleaned reticle is extremely low. For this reason, devices have been considered that automatically inspect the presence of foreign matter on the reticle, but the reticle is transported manually from the cleaning device to the inspection device, which simply reduces inspection time and visually detects the presence of foreign matter. Merely trying to reduce labor does not fundamentally solve the possibility of foreign matter adhesion.

(Objective of the Invention) The present invention eliminates the need to manually handle substrates such as photomasks and reticles, and automatically detects foreign substances attached to the substrate.
It is an object of the present invention to provide a cleaning device that can check the cleanliness and also allow the cleaned substrate to be taken out for transport to an exposure device or the like without being recontaminated.

(Summary of the Invention) The present invention provides a mounting mechanism that can mount a plurality of cases RC that horizontally hold a substrate to be cleaned (reticle, bunlang glass, etc.) in a substantially hermetically sealed state and store it in a horizontal state so that it can be taken out. (cartridge), and foreign matter inspection means 3 that inspects the presence or absence of foreign matter attached to the surface of the board while holding the board almost horizontally.
, cleaning means 7, 8, and 9 that clean the substrate while holding it almost vertically with the arm 5, a mounting mechanism, a foreign object inspection means, and a cleaning means, which are housed integrally to keep the internal environment clean. 1 and 2 constitute a cleaning device. In the present invention, the transport mechanisms 20 to 26, 3 are configured to transfer the board horizontally taken out from the case RC mounted on the mounting mechanism to the foreign object inspection means 3 in a horizontal state.
0 to 33, and attitude changing means 4 which receives the substrates carried by this transport mechanism in a horizontal state and converts the received substrates into a vertical state by rotating mechanisms M5, 47, and 48, and this attitude changing means. a drive mechanism M6, 49, 121 to 124 for delivering the substrate held in a vertical state by the means to the arm 5 of the cleaning means 7, 8, 9 in a vertical state; the transport mechanism, the attitude changing means; Control means 1 for controlling a series of substrate conveyance operations by a drive mechanism
50 to 164 are provided.

(Embodiment) FIG. 1 is a schematic diagram of the entire automatic cleaning apparatus to which an embodiment of the present invention is applied. The device main body 1 is
It has a clean unit 2 at the top that produces clean air free of dirt and dust, and the inside of the main body 1 of the device is shielded from the outside so that it is filled with the clean air. Glass substrates to be cleaned, such as photomasks and reticles with circuit patterns (hereinafter referred to as reticle R), are stored one by one in a reticle case RC.
A plurality of RCs (hereinafter simply referred to as case RCs) are attached to predetermined positions on the front of the main body 1 of the apparatus. As disclosed in, for example, Japanese Patent Laid-Open No. 57-39537, this case RC has a door at a position where the reticle R is taken in and out parallel to its surface, and when the reticle R is not taken out, this door is used. It is of such a structure that it can be closed tightly. In addition, the case RC is located between the surface of the reticle R on which the circuit pattern is drawn (hereinafter referred to as the "pattern surface") and the inner wall surface of the lower lid, and between the surface behind the pattern surface (hereinafter referred to as the "glass surface") and the upper lid. The structure is such that the periphery of the reticle R on the pattern surface side is supported so that a predetermined gap is maintained between the reticle R and the inner wall surface. Further, a plurality of cases RC can be stacked on a cartridge (not shown), and any case can be removed from the cartridge.

The reticle R housed in the case RC is sent to a foreign matter inspection device 3 that is provided in the device body 1 and inspects the presence or absence of attached foreign matter, its size, and the attachment position. The foreign object inspection device 3 is housed in a light-shielding box, and the light-shielding box is provided with an opening through which the reticle R is carried in and out. The sliding shutter plate SB is configured to open its opening when loading and unloading the reticle R, and to close the opening when inspecting foreign objects. The shutter plate SB is provided because the foreign matter inspection device 3 is configured to scan the reticle R with, for example, a laser beam to detect scattered light from foreign matter. In other words, if there is no shutter plate SB, stray light will enter through the opening and appear as noise in the detection of scattered light from foreign objects, adversely affecting detection sensitivity (size of foreign object) and detection accuracy (position of foreign object). be.

Now, during transportation from the case RC to the foreign object inspection device 3, the reticle R is held horizontally. On the other hand, since the reticle R is cleaned while being held vertically, the attitude changing mechanism 4 rotates the horizontal reticle R by 90° to bring it into the vertical state. The reticle R in the vertical state is transferred to the arm mechanism 5 for cleaning. The arm mechanism 5 is composed of two rods (arms) so as to sandwich both end surfaces of the reticle R. The arm transport mechanism 6 horizontally moves the arm mechanism 5 holding the reticle R along the tanks 7, 8, and 9 (cleaning device) arranged in the order of the cleaning process, and moves the reticle R into and out of each tank. move vertically. Here, tank 7 is
This cleaning tank is installed at the farthest position from the mounting position of the case RC, and sprays cleaning liquid onto the reticle R and scrubs it with a rotating brush.The tank 8 sprays alcohol onto the reticle R to remove excess water from the surface of the reticle R. and tank 9 is a steam drying tank that dries the reticle R using Freon steam.

Incidentally, in order to explain the conveyance state of the reticle R,
Define the three-dimensional coordinate system xyz. That is, when the main body 1 of the apparatus is viewed from the front as shown in FIG. 1, the movement of the reticle R up and down is defined as movement in the z direction.
Movement of the reticle R in the left-right direction is defined as movement in the y-direction, and movement of the reticle R in the front-rear direction is defined as movement in the x-direction. Of course, the x, y, and z directions are orthogonal to each other. In addition, when moving in the x direction, moving toward the front of the device main body 1, that is, toward the front, as shown in FIG. - Movement in the x direction. Similarly, for the y and z directions, set the direction of the arrow on the coordinate axes to + (plus).
, and the opposite direction is - (minus). Furthermore, when the attitude of the reticle R is horizontal, it means that the coordinate system
This means that the xy plane defined by
The yz plane, the pattern surface of the reticle R, and the glass surface are parallel (or coincident).

FIG. 2 is a specific perspective view of the automatic cleaning device shown in FIG. 1.

In FIG. 2, the reticle R stored in the case RC is carried in and out using a linear guide member 20 fixed perpendicularly to the device body 1 and a slider provided so as to be movable in the z direction along the linear guide member 20. Part 2
1, and a linear guide member 30 fixed to the slider member 21 so as to extend horizontally in the x direction.
, a slider member 31 provided movably in the x direction along this, and this slider member 31
This is carried out by a reticle loading/unloading mechanism comprised of an L-shaped loading/unloading arm 32 fixed to the reticle loading/unloading mechanism. Regarding this reticle loading/unloading mechanism, please refer to
As disclosed in detail in Publication No. 57-64930,
A brief explanation will be given here. The slider member 21 is moved in the z direction by a belt drive as shown in FIG. FIG. 3 shows the guide member 20
FIG. 2 is a perspective view showing a specific configuration of the slider member 21 and the slider member 21 . The slider member 21 is connected to the guide member 20 via a rolling element such as a roller bearing (not shown).
is supported by. A pulley 23 rotated by a motor 22 is provided at the bottom of the guide member 20, and a pulley 24 rotatably supported is provided at the top of the guide member 20. These pulleys 23,
A plurality of claws protruding at predetermined pitches are provided on the circumferential surface of 24 in the circumferential direction. Pulley 23, 24
A plurality of perforations (through holes) that engage with the claws of pulleys 23 and 24 are provided in the endless flat belt 25 that is stretched around the belt. Furthermore, the fixture 26 connects the slider member 21 and the flat belt 25 at one location.

In the above configuration, when the motor 22 is driven and the pulley 23 rotates clockwise in FIG. 3, for example, the pulley 24 also rotates clockwise. Therefore, the side of the flat belt 25 on which the fixture 26 is attached moves downward, and the slider member 21 also moves downward (-z
direction). Furthermore, when the rotation direction of the motor 22 is reversed, the slider member 21 moves upward (+z
direction).

Now, in FIG. 2, the guide member 30 and slider member 31 are also constructed in the same manner as in FIG. 3. Here, the motor 22 that moves the slider member 21 in the z direction is referred to as motor M1, and the motor that moves the slider member 31 in the x direction is referred to as motor M.
Set it to 2. Then, when the slider member 21 moves in the z direction, the guide member 30, slider member 31, and loading/unloading arm 32 also move in the z direction. Further, a mounting plate 33 on which the reticle R is placed and vacuum-adsorbed thereon is horizontally provided on the carry-in/out arm 32. The mounting plate 33 is attached to the x of the slider member 31.
Due to the movement in the direction, it enters the inside of the case RC,
At that time, the thickness and size (especially the width in the y direction) of the mounting plate 33 are determined so that it enters the gap between the pattern surface (lower surface) of the reticle R in the case RC and the inner wall surface of the case lower cover. It is being And mounting plate 3
3 is provided with an opening 33a having a size corresponding to a circuit pattern area formed of a metal thin film such as chromium on the pattern surface of the reticle R. Therefore, the mounting plate 33 is formed into a rectangular frame shape whose width in the y direction is narrower than the size of the reticle R, and the circuit pattern area of the reticle R does not come into contact with the mounting plate 33.

Incidentally, since the case RC is attached to the apparatus main body 1 with the door facing the mounting plate 33, the slider member 21 is provided with a mechanism for opening and closing the door when the reticle R is carried in and out. Figure 4 shows
FIG. 3 is a perspective view of the door opening/closing mechanism when the case RC is viewed from the mounting plate 33 side. This door opening/closing mechanism is also disclosed in detail in Japanese Unexamined Patent Publication No. 57-64930, so it will be briefly explained here. The door 100 of the case RC is opened by being flipped upward by a hinge 101. A linear groove 100 communicating in the vertical direction (z direction) is provided at the side end of the door 100.
A is engraved. Therefore multiple cases
When the RC is stacked on the device body 1,
The grooves 100a of each case RC are aligned linearly in the z direction. Now, the door opening/closing mechanism is that groove 100.
a pin 102 extending in the y direction that can be engaged with a; a member 104 having the pin 102 fixed to one end and a shaft 103 fixed to the other end; a base 105 rotatably supporting the shaft 103; A member 106 fixed to the other end of 103 and having a slit opening in the z direction.
and an air cylinder 107 provided in the base 105 and having a linearly movable piston for engaging the slit opening of the base 105 and driving the member 106 in the x direction. And the base 1
05 is fixed to the slider member 21 shown in FIG. With this configuration, case RC door 1
To open the air cylinder 107, pressurized gas is supplied to the air cylinder 107 or the air cylinder 107 is evacuated. Then member 10
6 rotates clockwise around axis 103 in FIG. Therefore, member 104 also rotates clockwise and pin 102 revolves around axis 103. As a result, the pin 102 engages with the lower side of the groove 100a and flips the door 100 upward. Then, when the stroke amount of the piston inside the air cylinder 107 becomes full, the pin 102 holds the door 100 substantially horizontally and opens the reticle R extraction port of the case RC. Also air cylinder 107
When gas supply or evacuation to the door 1 is stopped, the piston returns to its original position by the coil spring and closes the door 1.
00 is closed. Note that since the base 105 is provided on the slider member 21, the base 105 is provided on the slider member 21.
As the pin 102 moves in the z direction, the pin 102 also moves in the z direction. Therefore, this door opening/closing mechanism is
3 is the case RC containing the desired reticle R
The slider member 21 is provided so that the pin 102 engages with the groove 100a of the door 100 of the case RC when facing the case RC.

Now, as shown in FIG. 2, a foreign matter inspection device 3 is provided above the reticle loading/unloading mechanism.
The light shielding box 3a shields the foreign object inspection device 3 from external light, and the opening 3b is formed by the aforementioned shutter plate.
This is the entrance for the reticle R that is opened and closed by the SB. The guide member 34 extends linearly in the x direction and is fixed inside the light shielding box 3a, and the slider member 35 is
It is movable along this guide member 34 in the x direction. This slider member 35 is also moved by a belt drive as shown in FIG. The motor for driving the belt will hereinafter be referred to as motor M3. The slider member 35 is provided with a rectangular holding frame 36 that holds the reticle R horizontally. At the four inner corners of the holding frame 36, holding parts 36a are provided on which the four corners of the reticle R are placed and vacuum-adsorbed. Therefore, when the reticle R is placed on the holding portion 36a, both the upper surface (glass surface) and the lower surface (pattern surface) of the reticle R are exposed so that the laser beam can enter almost the entire surface thereof. Furthermore, the holding frame 36
As shown in the figure, when the slider member 35 is at the most moved position in the +x direction, it is located directly above the opening 3b, and the mounting plate 33
is provided so as to pass through the inside of the holding frame 36 when turned in the +z direction. A carrier 37 that suspends the reticle R in a horizontal state is provided directly above the opening 3b at a position where the mounting plate 33 has moved the most in the +z direction. This carrier 37 is arranged upwardly by a fixed distance from the holding frame 36 so as not to interfere with the transport path of the holding frame 36 in the x direction. FIG. 5 is a perspective view showing the specific structure of the carrier 37. The Carrier 37 has
Base plate 1 fixed horizontally within foreign object inspection device 3
10, a suction plate 111 attached to the lower surface of the base plate 110 via a leaf spring, and the base plate 11.
Four pressing members 112 are attached to the four sides of the reticle R and grip the reticle R by swinging so as to press the end face of the reticle R in a direction toward the center of the reticle R.
a, 112b, 112c, and 112d are provided. A synthetic resin roller 113 is rotatably supported on each of the pressing members 112a to 112d at a position where it comes into contact with the end surface of the reticle R. Furthermore, the lower end portions of each of the pressing members 112a to 112d,
That is, the reticle R is located below the roller 113 at a position where the roller 113 contacts the end face of the reticle R.
A claw 114 is provided that protrudes a minute amount toward the center. These pressing members 112a to 112d are
When the reticle R is located directly below the suction plate 111 at a predetermined minute interval, the rollers 113 are arranged so as to press the end surfaces of the four sides of the reticle R inward. The center axis of rotation of the pressing members 112a to 112d is set parallel to each side of the base plate 110, for example, and the rotation is caused by four air cylinders 115 provided radially on the upper surface of the base plate 110.
a, 115b, 115c, and 115d. When the air cylinders 115a to 115d are supplied with pressurized gas (or vacuum), each piston inside the cylinder moves toward the outside of the base plate 110 to press the reticle R. Similar to the air cylinder 107, the pistons of the air cylinders 115a to 115d are returned to their original positions by coil springs. However, the pressing operation of the reticle R in the y direction, that is, the movement of the roller 113 of the pressing member 112a in the +y direction and the pressing member 112
Of the movement of the roller 113 in the −y direction of c, the pressing member 112c is
The swing of c is limited by a stopper 116y provided on the base plate 110. The same applies to the pressing operation of the reticle R in the x direction, and the pressing member 112
The swinging of b is limited by a stopper 116x provided on the base plate 110. This stopper 11
6x, 116y are members 112 that press the reticle R.
This is for positioning the reticle R relative to the base plate 110, that is, positioning the reticle R relative to the foreign object inspection device 3, etc., when pressed in the x direction and the y direction at points a to 112d. Now, suction plate 111
The upper surface (glass surface) of the reticle R is suspended by vacuum suction. The suction is done by vacuum pads 11 provided at positions corresponding to the four corners of the reticle R.
7a, 117b, 117c, and 117d. These vacuum pads 117a to 117d are fixed to the suction plate 111, and the base plate 110
is not fixed. In addition, the air cylinder 115
Among a to 115d, stoppers 116x, 116
Air cylinder 115b limited by y,
The pressing force of 115c is the same as that of other air cylinders 115.
The pressure of the pressurized gas and the vacuum pressure are adjusted for each air cylinder so that the pressure is stronger than the pressing force of the cylinders a and 115d. Further, the claws 114 of the pressing members 112a to 112d slightly sink into the lower surface (pattern surface) of the reticle R when the roller 113 comes into contact with the end surface of the reticle R. This is to prevent the reticle R from falling if, for example, the evacuation of the vacuum pads 117a to 117d fails and the reticle R peels off from the suction plate 111.

Now, returning to the explanation of FIG. 2, the foreign matter inspection device 3
includes a laser light source 38, a mirror 39 that reflects the laser light from the laser light source 38, and a mirror 3.
Foreign object detection consists of a vibrating mirror 40 that reflects the laser beam from 9 and vibrates and rotates at a constant angle, and a mirror 41 that guides the laser beam deflected by the vibrating mirror 40 by a constant angle to the pattern surface of the reticle R. A mechanism is provided. This foreign object detection mechanism is disclosed in detail in, for example, Japanese Patent Application Laid-Open No. 58-62543 and Japanese Patent Application Laid-Open No. 58-62544, so it will be briefly explained here. When the reticle R is placed on the holding frame 36 and moves in the -x direction, the laser beam from the mirror 41 scans the pattern surface of the reticle R by 70° to 80°.
Scan in the y direction at an incident angle of . Furthermore, although not shown in FIG. 2, a plurality of photodetectors (for example, photomultiplier tubes) are arranged so as to obliquely view the scanning trajectory from different directions. These photoelectric detectors are arranged in pairs, one looking into the pattern surface of the reticle R and the other looking into the glass surface. Of the scattered light from the foreign matter adhering to the scanning trajectory of the reticle R, the scattered light generated in the space on the pattern surface side and the scattered light generated in the space on the glass surface side are separately photoelectrically detected. By comparing all of the photoelectric signals, it is possible to determine not only whether or not a foreign object is attached, but also the size and state of attachment of the foreign object, such as whether it is attached to the pattern surface or the glass surface, or whether it is attached to the pattern surface side. It is possible to detect whether a foreign substance is attached to a thin metal film such as chromium (light-shielding part) or glass (transparent part). Further, means for measuring the scanning position of the laser beam in the y direction (referred to as main scanning) and means for measuring the position of movement of the holding frame 36 of the reticle R in the x direction (referred to as sub-scanning) are provided. By detecting the laser beam irradiation position on the reticle R when the reticle receives the scattered light from the foreign object, the adhesion position of the foreign object is determined.

On the other hand, the attitude change mechanism 4 receives the reticle R taken out from the case RC and placed on the mounting plate 33. The guide member 42 extends linearly in the y direction and is attached to the main body 1 of the apparatus. This guide member 4
2 has a T-shaped cross section and guides the movement of the slider member 43 in the y direction. The slider member 43 is also moved by a belt drive as shown in FIG. The motor for driving it is motor M4. Further, the slider member 43 moves in the y direction between a position directly below the mounting plate 33 and a position facing the arm mechanism 5. Slider member 4
Two support columns 44a and 44b are vertically fixed to the column 3, facing each other in the y direction. A prismatic member 45 is arranged so as to be sandwiched between the pillars 44a and 44b, and a mounting table 46 for holding the reticle R is fixed to the upper part of the prismatic member 45. This prismatic member 45 has a shaft 47 which is rotatably supported by the pillars 44a and 44b.
is provided, and this shaft 47 is rotated by 90° via a worm wheel 48 by a motor M5 fixed to the column 44b. Therefore, the mounting table 46 and the prism member 45 move clockwise in FIG. 2 between the first state in which the reticle R is held horizontally and the second state in which the reticle R is held vertically as shown in FIG. Rotate by 90°. The mounting table 46 is composed of a base plate 49 fixed to the prismatic member 45, and a holding plate 50 supported on the base plate 49 via a spring.
The holding plate 50 has a holding part 50a formed in a U-shape and protruding in the +z direction when viewed from above, and holds the periphery of the reticle R by vacuum suction. Further, the recess 50b inside the U-shaped holding portion 50a is such that the mounting plate 33
It is formed into a rectangular shape so that it can be entered from any direction. Further, a slot 50c extending in the x direction is formed under the holding part 50a so that the mounting plate 33 inserted into the recessed part 50b passes through the lower part of the holding part 50a horizontally in the y direction. The outer circumferential size of the holding part 50a is determined to be almost the same as the size of the reticle R, and tapered notches 50d that the reticle R does not come into contact with are formed in the parts of the holding part 50a corresponding to the four corners of the reticle R. ing. By the way, the mounting table 46 is configured to be movable in the z direction with respect to the prismatic member 45 when in the first state as shown in FIG. FIG. 6 is a partial sectional view showing the moving mechanism of the mounting table 46, and shows the state when the mounting table 46 is rotated 90 degrees from the state shown in FIG. 2 so as to hold the reticle R vertically. be. As described above, the holding plate 50 of the mounting table 46 is supported by the pedestal plate 49 by a plurality of springs 49a. When the reticle R is received by the holding part 50a and vacuum-adsorbed, the holding plate 50 is placed against the base plate 49 so that the surface of the reticle R (pattern surface or glass surface) and the surface of the holding part 50a are in close contact. This is to allow it to tilt slightly. Now, prismatic member 4
5, as shown in FIG. 6, an outer frame 120 provided with a shaft 47; an inner frame 121 slidably fitted into the outer frame 120 and fixed to a base plate 49; A motor M6 fixed to the bottom of the outer frame 120, a feed screw 122 directly connected to the rotating shaft of the motor M6 and arranged inside the inner frame 121, and a feed screw 122 fixed to the bottom of the inner frame 121. It is comprised of a nut 123 that is screwed into the feed screw 122, and a bearing 124 that rotatably supports the end of the feed screw 122 on the side opposite to the motor M6 on the outer frame 120. Therefore, when the motor M6 is driven to rotate the feed screw 122, the inner frame 121 is guided by the outer frame 122 and moves in the left-right direction in FIG. 6. Therefore, the mounting table 46 also moves in the left-right direction, that is, in the x direction. Of course, in the state shown in FIG. 2, the mounting table 46 moves in the z direction. still,
When the reticle R is set vertically as shown in FIG. 6, the weights are balanced so that the mounting table 46 and the prismatic member 45 are balanced as much as possible with the shaft 47 as the fulcrum. This is to minimize the load applied to the motor M5 for rotating the shaft 47.

Now, as shown in Figure 6, the reticle R is made vertical.
is held between the lower ends of the square-shaped arms 52R and 52L of the arm mechanism 5. Arm 52R,
52L is elongated in the z direction, and its length is the same as that of the reticle R.
It is determined so that it can be lowered to a predetermined position within the tanks 7, 8, and 9. Arm 52R, 52L
Shafts 54R, 54L extend in the x direction on the upper end side, and these shafts 54R, 54L are rotatably supported by the arm support portion 53. FIG. 7 is a perspective view showing the detailed structure of the arm support portion 53. In FIG. 7, a lever 130R is attached at right angles to a shaft 54R fixed to an arm 52R, and a spring 131R is provided between one end of the lever 130R and the upper wall of the arm support portion 53. This spring 1
31R generates a tensile force that constantly urges one end of lever 130R upward. Stopper 132
is for locking the upward movement of one end of the lever 130R. Therefore, one end of the lever 130R normally comes into contact with the stopper 132 due to the biasing force of the spring 131R, so that the lever 130R is kept almost horizontal and the arm 52R is kept vertical as shown in FIG. . Therefore, from its vertical position, the arm 52R can rotate counterclockwise around the shaft 54R against the urging force of the spring 131R, but the stopper 132 prevents the arm 52R from rotating clockwise from the vertical position. It will be locked. Further, a detector 133 provided near the lever 130R detects whether the lever 130R is horizontal. In other words, this detector 133 does not output a detection signal when the arm 52R is vertical;
is configured to output a detection signal when it is tilted from a vertical state. In addition, this detection is
The same thing can be done even if whether or not one end of the lever 130R is in contact with the stopper 132 is detected by the presence or absence of electrical continuity. On the other hand, arm 52
Similarly for L, the lever 13 is perpendicular to the shaft 54L.
0L is fixedly installed, and a spring 131L is installed at one end of the lever 130L. The spring 131L generates a tensile force that urges one end of the lever 130L upward, but this tensile force is set to be smaller than the tensile force of the spring 131R. Therefore arm 5
2L can rotate counterclockwise around the shaft 54L by the biasing force of the spring 131L, and can also rotate clockwise against the biasing force of the spring 131L. In addition, the detectors 134 and 135 are connected to the lever 1.
30L to detect the position of the lever 130L. Specifically, when the arm 52L is in a vertically hanging state, the lever 130L is horizontal, and in this case, neither of the detectors 134 and 135 outputs a detection signal. When the arm 52L rotates clockwise from its vertical position and tilts,
Only the detector 135 outputs a detection signal, and conversely, when the arm 52L rotates counterclockwise and tilts, only the detector 134 outputs a detection signal. Now, the arm support portion 53 is coupled to the arm transport mechanism 6 via a square member 55 extending in the x direction.

Incidentally, four claw members 56, 57, 58, and 59 made of a synthetic resin material are provided at the lower ends of the arms 52R and 52L to hold the four corners of the reticle R. These claw members 56 to 59 are arranged so that when the two arms 52R and 52L are vertical, the arms 52R and 52L are arranged so as to sandwich the four corners of the reticle R.
52L, respectively. FIG. 8 shows this arm 52L and two claw members 5 provided thereon.
6 and 57. FIG. The claw members 56, 57 are horizontal to the arm 52L.
It has a parallelogram shape tilted by about 30 degrees, and the reticle R
are fixed vertically apart by the length of one side. The end surfaces of the claw members 56 and 57 each have a reticle R.
Of the four corners, V-shaped cuts 56a and 57a are formed to sandwich the two left corners. The cut 56a of the claw member 56 located above is provided at the lower part of the right end of the claw member 56 so as to sandwich the upper left corner of the reticle R, and the cut 56a of the claw member 56 located below is provided at the lower part of the right end of the claw member 56.
The notch 57a is provided at the upper right end of the claw member 57 so as to sandwich the lower left corner of the reticle R.

FIG. 9 is a side view of FIG. 8, looking at the claw member 56 and arm 52L from the side of the reticle R held by the claw member 56. FIG. 10 is an end view taken along the line A--A in FIG. 8. The corners of the reticle R are shown in Figure 9, 1.
As shown in FIG. 0, it is inserted into a V-shaped notch 56a. Generally, the end faces of glass substrates such as reticles and photomasks are all chamfered, so if the angle of the V-shape of the notch 56a is determined in accordance with this chamfer, the reticle R can be held securely. The notch 57a is also determined in the same manner. Further, the claw members 56 and 57 are provided on the arm 52L in an inclined manner, but the oblique sides 56b and 56c of the claw member 56 are
is formed so as to rise as it approaches the reticle R, that is, upwardly to the right in FIG. When cleaning the reticle R, the oblique side 56
This is to allow drops of cleaning liquid, pure water, etc. remaining on b or 56c to flow in the direction opposite to the reticle R, that is, to improve drainage. Now, a knife-shaped edge EG is formed on the end face facing the reticle R at the lower end of the arm 52L.
FIG. 11 is a cross-sectional view taken along the line B--B in FIG. 8, crossing this edge EG. This edge
An arm opening/closing mechanism for rotating the arm 52L around the shaft 54L comes into contact with the EG. In addition, regarding the arm 52R, the claw member 5 of the arm 52L
Claw members 58 and 59 similar to 6 and 57 are provided. The positions of the claw members 58 and 59 are as shown in FIG.
6 and 57, a V-shaped cut 58a carved in the claw member 58 sandwiches the upper right corner of the reticle R, and a V-shaped cut 59a carved in the claw member 59 on the right side of the reticle R. Tuck the bottom corner. Furthermore, an edge EG is similarly formed on the end face facing the reticle R at the lower end of the arm 52L.

As shown in FIG.
Accordingly, the opposing claw members 56 and 58 and the claw members 57 and 59 are closed toward each other or opened apart from each other. The arm opening/closing mechanism 60 is provided with a rotating piece 63 that engages with the edge EG of the arm 52L when the shaft 62 rotates, and a rotating piece 65 that engages with the edge EG of the arm 52R when the shaft 64 rotates. It will be done. When the rotating pieces 63, 65 are almost vertical as shown in FIG.
2L and 52R are both vertical. From this state, the rotating piece 63 rotates counterclockwise in the figure, and the rotating piece 64
rotates clockwise in the figure, the two arms 52R,
52L is a spring 131R, 1 inside the arm support part 53.
It opens against the urging force of 31L. Rotating pieces 63, 64
When the arms 52R and 52L rotate in the opposite direction, the arms 52R and 52L are closed by the urging force of the springs 131R and 131L. FIG. 12 is a perspective view showing the detailed structure of the arm opening/closing mechanism 60. The rotating piece 63 actually has a rotatably supported roller 63a made of a synthetic resin material, as shown in FIG. This roller 63a has a V-shaped groove in its circumferential direction that fits into the edge EG of the arm 52L. The shaft 62 fixed to the rotating piece 63 is provided with a worm gear 62a and a lever 62b for detecting the rotational position of the shaft 62. The worm gear 62a is rotated by a worm wheel 62c fixed to the rotating shaft of the motor M7. The detectors 140, 141 detect the position of the rotating piece 63, that is, whether the arm 52L is closed or opened, by detecting the rotational position of the lever 62b. Specifically, as shown in FIG. 12, the detector 140 detects when the rotating piece 63 rotates by a predetermined angle clockwise from the position where the rotating piece 63 is vertical and the arm 52L is vertical. Output a signal. Furthermore, when the rotating piece 63 rotates counterclockwise from the vertical position and the lower end of the arm 52L opens to the left (-y direction) by a predetermined angle in FIG. 2, the detector 141 outputs a detection signal. .

On the other hand, the rotating piece 65 and the shaft 64 are also provided with a motor M8 that rotates the rotating piece 65 and detectors 142 and 143 that detect the position of the rotating piece 65, as in FIG. 12, although they are not shown. ing. However, the driving of this motor M8 and the aforementioned motor M7 are interlocked, and furthermore, the rotating piece 65 is driven by the rotating piece 63.
It is constructed so that it always rotates in the opposite direction to the direction of rotation. Of course, a roller having a V-shaped groove is rotatably provided at the tip of the rotating piece 65, and the V-shaped groove of the roller is connected to the edge of the lower end of the arm 52R.
mated with.

When the arms 52R, 52L are opened by a predetermined angle by the arm opening/closing mechanism 60 as described above, the distance between the claw members 56 and 58 provided on the arms 52R, 52L, and the distance between the claw members 57 and 59 are changed. The distances between both are larger than the width in the y direction of the reticle R in the vertical state. Then, after rotating the mounting table 46 of the attitude changing mechanism 4 by 90 degrees as shown in FIG.
The corners are provided with cuts 56 of the claw members 56 to 59, respectively.
a, 57a, 58a, and 59a. After that, when the motors M7 and M8 are driven, the arm 52
R, 52L begin to close, and the notches of the claw members 56 to 59 sandwich the four corners of the reticle R. At this time, since the holding portion 50a is provided with notches 50d at the four corners, the claw members 56 to 59 do not collide with the holding portion 50a.

Now, the reticle R held by the arms 52R and 52L is transported toward the tanks 7, 8, and 9 by the arm transport mechanism 6 that moves in the z direction and the y direction. As shown in FIG.
It moves up and down in the z-direction along a guide 71 extending linearly in the z-direction by a slider 70 connected to the slider 5. This guide 71 is not fixed to the main body 1 of the apparatus, but is fixed to the slider 72. slider 7
2 is moved linearly in the y direction by a guide 73 extending linearly in the y direction in the main body 1 of the apparatus. The guide 71 is provided with a motor M9 for driving the slider 70 with a belt as in FIG. 3, and the guide 73 is similarly provided with a motor M10 for driving the slider 72 with a belt. The guide 71 has a T-shaped cross section so that the slider 70 does not interfere with the slider 72. Therefore, the slider 70 can freely move up and down from the position shown in FIG. 2 to the lower end of the guide 71.

Slit-shaped openings 7a, 8a, and 9a are provided on the upper surfaces of the tanks 7, 8, and 9, respectively. The openings 7a, 8a, and 9a are all elongated in the y direction, and each opening is arranged in the y direction. The reticle R held by the arms 52R, 52L is carried by the arm transport mechanism 6 in the y direction, that is, in a direction parallel to the surface of the reticle R, and is positioned above the openings 7a, 8a, 9a. Through the opening, the arms 52R and 52L move forward and backward into the tank.

The configuration of the reticle R conveyance device has been described above, and the slider 2 in the reticle conveyance mechanism is
1 and the slider 70 in the arm transport mechanism 6 are each provided with a balance weight to reduce the load on the motors M1 and M9 during upward movement (movement in the +z direction). For example, a pulley is provided at the upper end of the guide 20,
One end of a wire is fixed to the slider 21, and the wire is passed around a pulley, and a balance weight is fixed to the other end.

Next, the control system of this apparatus will be explained based on the circuit block diagram of FIG.

Microprocessor (hereinafter referred to as MPU) 1
Reference numeral 50 controls the sequence of the entire device according to a program, and includes a memory circuit (RAM,
ROM, etc.). An interface circuit (hereinafter referred to as IF) 151 sends commands to each mechanism of the device and information from the detector to the MPU 1.
50 can be input/output.

The foreign object detection circuit 152 is connected to the foreign object inspection device 3 described above.
Foreign matter adhering to the reticle R is detected by inputting photoelectric signals from a plurality of photoelectric detectors provided therein. The specific configuration of this circuit 152 was published in Japanese Patent Application Laid-Open No. 58
It is disclosed in detail in the -62544 publication. Also,
The foreign object detection circuit 152 also includes a detection circuit for detecting the main scanning position and sub-scanning position of the laser beam on the reticle R in order to detect the adhesion position of the foreign object. The solenoid valve 153 switches whether or not pressurized gas is supplied (or evacuated) to the air cylinder 107 for opening and closing the door 100 of the case RC shown in FIG. It is actuated by the drive circuit 154 on command. The drive control circuit 155 receives instructions from the MPU 150.
Controls the amount of drive of motors M1 and M2 of the reticle transport mechanism. The motor MS slides the shutter plate SB shown in FIG. 1, and is operated via the drive circuit 156 in response to commands from the MPU 150. The drive circuit 156 controls the motor MS so that the shutter plate SB slides between a position where the opening 3b of the foreign object inspection device 3 is fully opened and a position where it is fully closed. The solenoid valve 157 is connected to the air cylinder 1 of the carrier 37 shown in FIG.
This is to switch whether or not to supply pressurized gas (or evacuation) to MPU 15a to 115d.
It is operated by a drive circuit 158 which receives commands from 50. The drive control circuit 159 controls the amount of drive of the motor M3 that moves the slider 36 in the foreign object inspection device 3 based on a command from the MPU 150. The drive control circuit 160 controls the motors M4, M5, and M of the posture change mechanism 4 according to commands from the MPU 150.
Controls the drive amount of 6. The drive control circuit 161 controls the amount of drive of the motors M7 and M8 in the arm opening/closing mechanism 60. However, motors M7 and M8 are connected in parallel, and the amount of drive of both motors is the same. Four detectors 140, 14 in the arm opening/closing mechanism 60
1, 142, 143 detection signals S1, S2, S
3. S4 is a binary signal and is sent via IF151.
Input to MPU150. Each detection signal S5, S6, S7 of the three detectors 133, 134, 135 in the arm support part 53 is a binary signal, and the IF15
1 to the MPU 150. The drive control circuit 162 controls the amount of drive of the motors M9 and M10 of the arm transport mechanism 6 based on commands from the MPU 150. Note that the MPU 150 is connected to a keyboard device 163 for inputting operator commands, and a display device 164 for displaying the progress status of the sequence, the results of foreign object inspection, etc.

Next, the operation of this apparatus will be explained based on the flowcharts shown in FIGS. 14 and 15.

It is assumed that a plurality of cases RC of the reticle R are attached to the main body 1 of the apparatus in advance. First, the operator inputs from the keyboard device 163 which case the reticle is to be cleaned. Then
MPU150 motor M2, in steps 200 and 201,
A drive command is output to M3 to position the carry-in/out arm 32 and the holding frame 36 to the retracted position where they have been moved most in the -x direction. Next, the MPU 150 steps
202 outputs a drive command to the motor M1, and the door 1 of the case RC is inputted from the keyboard device 163.
The loading/unloading arm 32 is searched in the vertical direction so that the loading/unloading arm 32 faces the mounting plate 33. next step
At 203, the MPU 150 outputs a drive command to the solenoid valve 153 to open the door 100 of the case RC. step
At 204, the MPU 150 outputs a drive command to the motor M2 to cause the mounting plate 33 to enter the inside of the case RC, that is, between the pattern surface of the reticle R and the inner wall surface of the lower cover. And in step 205 MPU15
0 outputs a drive command to the motor M1 and moves the mounting plate 3
3 is increased slightly (by +Δz) in case RC. As a result, the reticle R is slightly lifted from the mounting surface inside the case RC. step
At 206, the MPU 150 starts a vacuum suction operation (vacuum on) of the reticle R to the mounting plate 33.
In step 207, the MPU 150 outputs a drive command to the motor M2 to carry the mounting plate 33 out of the case RC and move it in the -x direction to the retracted position. Then, in step 208, the MPU 150 stops issuing a drive command to the solenoid valve 153. At this time, the piston is automatically pushed back to its original position by a coil spring installed inside the air cylinder 107 of the door opening/closing mechanism.
The door 100 of case RC is closed.

Next, the MPU 150 starts the motor at step 209.
Output a drive command to the MS and open the shutter plate SB. Then, in step 210, the MPU 150 outputs a drive command to the motor M1 to move the mounting plate 33 to +z
move in the direction. The movement is such that the reticle R passes through the opening 3b and the suction plate 111 of the carrier 37
This is done until it comes into contact with the Since the suction plate 111 is supported by a spring on the base plate 110, even if the reticle R comes into contact with it and slightly overruns, the overrun is absorbed by the expansion and contraction of the spring. Therefore, the reticle R will not be damaged. Moreover, because the suction plate 111 can be slightly tilted with respect to the base plate 110 due to the spring,
Even if the reticle R is not completely horizontal, the upper surface of the reticle R (glass surface in this embodiment) and the suction plate 11
It is in complete contact with the suction surface of 1. Next MPU15
0, the vacuum suction operation of the mounting plate 33 is canceled (vacuum off) in step 211, a drive command for the solenoid valve 157 is output in step 212, and the carrier 37 is
The air cylinders 115a to 115d are operated.
As a result, the pressing member 112a of the carrier 37~
Each roller 113 of 112d presses against the end face portion of the reticle R to position the reticle R and also clamps the reticle R. In the next step 213
The MPU 150 determines whether to perform a foreign matter inspection inputted in advance from the keyboard device 163 before cleaning, or to perform cleaning without performing a foreign matter inspection. In this case, since a foreign object is to be inspected, the process proceeds to step 214, and vacuum suction of the suction plate 111 of the carrier 37 is started (vacuum on). As a result, the reticle R is fixed to the suction plate 111. Then, in step 215, the MPU 150 outputs a drive command to the motor M1 to move the mounting plate 33 in the -z direction (downward).
Move to. The amount of movement is determined so as not to block the movement path of the holding frame 36 in the x direction, for example, the height of the opening 3b. Then in step 216
The MPU 150 outputs a drive command to the motor M3 to move the holding frame 36 in the +x direction, and the carrier 37
Position it directly below. MPU15 in step 217
0 moves the mounting plate 33 in the +z direction and starts vacuum suction in step 218. At this time, the mounting plate 33 passes through the inside of the holding frame 36 and comes into contact with the lower surface of the reticle R held by the carrier 37.
Attract the bottom surface of the reticle R. Next MPU150
In step 219, the operation of the solenoid valve 157 is stopped.
At this time, the air cylinder 115a of the carrier 37~
The piston 115d is returned to its original position by an internal coil spring, and the pressing members 112a to 112d
The roller 113 is separated from the end surface of the reticle R,
The positioning operation is canceled. Then step 220
The vacuum suction operation of the suction plate 111 of the carrier 37 is released (vacuum off), the mounting plate 33 starts moving in the -z direction in step 221, and at the same time, the holding frame 36 starts the vacuum suction operation in step 222. do. As the mounting plate 33 moves in the -z direction, the four corners of the lower surface of the reticle R touch the holding portion 36 of the holding frame 36.
a, and in step 223, the vacuum suction of the mounting plate 33 is released. Thereafter, the mounting plate 33 further moves in the -z direction and waits at the position shown in FIG. 2, that is, the position a in FIG. 1. In each of the above steps, the reticle R is delivered to the foreign object inspection device 3, and in step 224, the MPU 150 outputs a command to close the shutter plate SB to the motor MS.
At this time, the reticle R is positioned at position i in FIG. 1, that is, the foreign object inspection position. Next, in step 225, the holding frame 36 is moved in the -x direction at a predetermined speed for inspection. This movement is
The laser beam for foreign matter inspection is applied to a position where the entire surface of the reticle R is scanned, and during this time, in the next step 226, a foreign matter inspection is performed in which scattered light from the foreign matter is photoelectrically detected. For foreign object inspection, for example, while the reticle R is moving in the -x direction (sub-scanning), the pattern surface of the reticle R is irradiated with a laser beam as shown in Figure 2, and the reticle R is
Turn around +x from the point when is located in the -x direction most
While moving in the direction, the optical path of the laser beam is switched so that the laser beam illuminates the glass surface of the reticle R. The switching structure is described in Japanese Patent Application Laid-open No.
It is disclosed in Publication No. 58-79240. When the foreign object inspection is completed, the holding frame 36 is moved in the +x direction in step 227, and the reticle R is positioned directly below the carrier 37. Next, in step 228, the shutter plate SB opens, and in step 229, the mounting plate 33 moves in the +z direction, passes through the opening 3b, and attaches to the holding frame 36.
It is located on the lower surface of the reticle R held by the reticle R. Then, in step 230, the vacuum suction of the holding portion 36a of the holding frame 36 is released, and the reticle R is transferred to the mounting plate 33, further raised, and comes into contact with the suction plate 111 of the carrier 37. In the next step 231, the carrier 37 starts positioning the reticle R in the same way as in the previous step 212, and in step 232 the suction plate 111 vacuum-chucks the reticle R. As a result, the reticle R is held in a suspended state on the carrier 37, and in step 233, the mounting plate 33 is moved to the position of the opening 3b.
Move in the z direction. At step 234, the holding frame 36 moves in the -x direction from directly below the carrier 37 and returns to the retracted position. At step 235, the mounting plate 33 is turned to + again.
It moves in the z direction and comes into contact with the lower surface of the reticle R held by the carrier 37. and step 236
The vacuum suction of the suction plate 111 is released and the step
At 237, vacuum suction of the mounting plate 33 is started. Then, in step 238, the positioning (pressing) operation by the pressing members 112a to 112d of the carrier 37 is canceled as in the previous step 219. At step 239, the mounting plate 33 holding the reticle R is moved in the -z direction to position a in FIG. 1, and at step 240, the shutter plate SB is closed.

Now, as a result of the foreign object inspection, if there is almost no foreign object attached to the reticle R, or if the foreign object is small enough to not be exposed even if it is attached, the MPU 150 determines that cleaning is not necessary and removes the reticle R from the case.
Return to RC. Also, if the inspection results show that there is too much foreign matter attached, the case is returned to the RC. This is when cleaning the reticle R that is too contaminated.
This is because, on the contrary, the insides of the cleaning tanks 7, 8, and 9 will be contaminated. The display device 164 displays whether to return to the case RC or clean it, and if it is to be returned, the contamination state of the reticle R is also displayed. Here, the case where the reticle R is cleaned will be explained.

In step 241, the MPU 150 outputs a drive command to the motor M4 to move the mounting table 46 of the attitude change mechanism 4 to -
It is moved in the y direction and positioned directly below the mounting plate 33. In the next step 242, the MPU 150 starts a vacuum suction operation for the holding plate 50 of the mounting table 46, moves the mounting plate 33 in the -z direction by a minute amount Δz in step 243, and at the same time, in step 244, vacuum suction of the mounting plate 33 is performed. Cancel the suction operation. As a result, the reticle R is attracted to the holding portion 50a of the holding plate 50, and the mounting plate 33 is positioned within the recessed portion 50b. Then, in step 245, the MPU 150 outputs a drive command to the motor M4 to move the mounting table 46 in the +y direction until it faces the arm mechanism 5. At this time, the mounting plate 33
passes through the slot 50c of the holding plate 50. When the mounting table 46 is positioned as shown in FIG. 2, the MPU 150 outputs a drive command to the motor M5 in step 246 to move the mounting table 46 as shown in FIG.
Rotate 90°.

Next, in step 247 of FIG. 15, the MPU 150 outputs a drive command to the motors M7 and M8 to open the arm mechanism 5. When the rotating pieces 63 and 65 rotate due to the drive of the motors M7 and M8, the arm 52
Both R and 52L open, and arms 52R and 52L open.
When the reticle R is opened to the extent that the reticle R can be caught, the detectors 133 and 134 shown in FIG. When the arm opening/closing mechanism 60 is fully opened, the detectors 141 and 143 output detection signals S2 and S4, respectively. The MPU 150 uses its detection signals S5, S6, S
2. It is detected that all S4 signals have been output, and the process advances to the next step 248. This is a confirmation operation to ensure that the reticle R is transferred to the arm mechanism 5. In step 248, the MPU 150 outputs a drive command to the motor M6 to move the mounting table 46 in the state shown in FIG. 6 by a predetermined amount in the -x direction. As a result, 4 of the reticle R attracted to the holding plate 50
The corners face four claw members 56, 57, 58, and 59 of arms 52R and 52L, respectively. step
At 249, the MPU 150 outputs a drive command to the motors M7 and M8 to rotate the rotary pieces 63 and 65 in the opposite direction to close the arms 52R and 52L. The rotation is caused by the rollers 63a, 65 of the rotating pieces 63, 65.
When a separates from the edge EG of the arms 52R, 52L and moves the arms 52R, 52L in the y direction, its lower end touches the rotating pieces 63, 65 and the roller 63.
This is done to a position where it does not interfere with a and 65a. At this time, the notches 56a of the claw members 56 to 59
When ~59a holds the four corners of the reticle R, the detectors 133, 134, 135 in the arm support 53
Neither outputs detection signals S5, S6, and S7,
On the other hand, the detectors 140 and 14 in the arm opening/closing mechanism 60
2 output detection signals S1 and S3, respectively.
The MPU 150 monitors these detection signals and executes the next step 250 after confirming that the detection signals S1 and S3 are output and the other detection signals S2 and S4 to S7 are not output. Note that when the reticle R is not held by the claw members 56 to 59, the arm 52L closes to a predetermined limit, and the detector 135 outputs the detection signal S7. Now, in step 250, the MPU 150 cancels the vacuum suction operation of the holding plate 50, and in step 251, moves the mounting table 46 to +x.
Return to direction. As a result, the reticle R is moved to the arm 52.
R, 52L. At this time, arm 52
R and 52L are maintained vertically together by the action of springs 131R and 131L. Next, in step 252, the MPU 150 outputs a drive command to the motor M10,
The reticle R held by the arm mechanism 5 is conveyed in the +y direction from position b shown in FIG. 1 (position shown in FIG. 2) to position c above the tank 7. MPU in step 253
150 outputs a drive command to the motor M9 to move the arm mechanism 5 in the -z direction and lower the reticle R to position d in the tank 7. Here, the reticle R is sprayed with a cleaning liquid and rubbed with a rotating brush to be cleaned. After cleaning in tank 7, the reticle R
is pulled up to position c, then step 254
Then, it is moved in the -y direction and transported to position e above the tank 8. Then, in step 255, the reticle R is lowered to a position f in the tank 8, and an alcohol solution is sprayed onto it. (Rinsing step with alcohol) Next, the reticle R is pulled up to position e, then transported in the -y direction to position g in step 256, and lowered to position h in bath 9 in step 257, where it is steam-dried. The dried reticle R is pulled up to position g and then transported in the -y direction to position b in step 258. Next, in step 259, the mounting table 46 moves in the -x direction, and the holding portion 50a of the holding plate 50
comes into contact with the surface of the reticle R (here, the pattern surface). At this time, even if the reticle R is not exactly vertical but slightly tilted due to cleaning, the holding plate 50 is supported by the pedestal plate 49 with a spring 49a so that it can be slightly tilted, so that it will stick tightly to the surface of the reticle R. do. Then, the MPU 150 starts vacuum suction of the holding plate 50 in step 260, opens the arm mechanism 5 in step 261, and separates the claw members 56 to 59 from the four corners of the reticle R. Next, in step 262, the mounting table 46 returns to the +x direction, and in step 262, the arm mechanism 5 is closed. As a result, the reticle R is held on the mounting table 46, and then, in step 264, the mounting table 46 is rotated -90 degrees in the opposite direction to the previous step, so that the reticle R is held on the mounting table 46.
Make the posture horizontal. Then, in step 265, the mounting table 46 is moved in the -y direction and positioned at a position a (see FIG. 1) such that the mounting plate 33 passes through the slot 50c of the holding plate 50 and enters the recess 50b. Ru.

The reticle R transported in the above manner is sent again to the foreign matter inspection device 3, and is inspected to see whether the cleanliness required for the reticle R is satisfactory, that is, whether foreign matter has been sufficiently removed. the result,
If the foreign matter has been sufficiently removed, the reticle R is stored in the case RC from the foreign matter inspection device 3 via the reticle loading/unloading mechanism. Also, if the inspection results show that foreign matter still remains, clean it again. However, if it is determined that foreign matter remains after performing re-cleaning a predetermined number of times, it is possible that the reticle R has a large scratch other than the foreign matter. In this case as well, reticle R is the case.
It is stored in the RC, and a display to that effect is displayed on the display device 164.

Note that if the degree of contamination of the reticle R housed in the case RC is known in advance, for example, by another foreign object inspection device, the operator inputs this information from the keyboard device 163. Then, in the flowchart of FIG. 14, in step 213, the MPU 150 determines not to perform a foreign object inspection, and proceeds to step 237 to immediately perform a cleaning process.

As described above, according to the embodiment of the present invention, once the reticle R is stored in the case RC, the reticle R can be cleaned without any manual intervention, and the reticle R after cleaning can be returned to the case RC. Since it is automatically stored in the RC, there is an advantage that foreign matter does not adhere to the reticle R again and an extremely clean reticle can be obtained. Moreover, since multiple Case RCs can be installed in the main body 1, multiple reticles can be reliably cleaned while inspecting them for foreign objects one by one.
In addition to reducing the effort required to replace reticles, the cleaning processing time for multiple reticles is significantly reduced. Furthermore, after the reticle R housed in the case RC is taken out by the mounting plate 33, it is once positioned by the carrier 37 in the foreign object inspection device 3, and then transported for foreign object inspection or cleaning. This is because if the reticle R is misaligned and stored inside the case RC, if a foreign object inspection is performed as it is,
The accuracy of detecting the position of foreign matter decreases, and
When the reticle R is transferred to the arm mechanism 5 via the posture change mechanism 4 for cleaning,
This is to solve the problem that the four corners of the reticle R and the claw members 56 to 59 are misaligned and the arms 52R and 52L fail to pick up the reticle R. Therefore, the reticle R is once positioned using the carrier 37 in the foreign object inspection device 3. Furthermore, the arms 52R and 52L are provided with an arm support portion 53.
Since the reticle R is always held with a constant force only by the urging force of the springs 131R and 131L, the reticle R
The reticle R will not be removed unless the arm opening/closing mechanism 60 is used. Therefore, even if the apparatus goes out of control, the reticle R is less likely to be dropped, and transportation with high safety and reliability is possible.

Further, in this embodiment, the claw members 56 to 58 are provided at an angle of about 30 degrees from the horizontal with respect to the arms 52R and 52L, but the angle is determined as appropriate depending on the viscosity of the cleaning liquid, etc. If the temperature is around 100°C, a draining effect can be obtained. Furthermore, since only the four corners of the reticle R are held by the claw members 56 to 58, liquids such as cleaning liquid or alcohol that accumulate at the lower end of the vertical reticle R can be easily removed, and liquid stains can be removed from the reticle R after drying. It also has the effect of leaving nothing behind.

Furthermore, since the reticle R is cleaned in a vertical position, it is possible to clean both sides (pattern surface, glass surface) under the same conditions (for example, brushing both sides at the same time), which has the advantage of providing high cleaning performance. be.

Now, the performance evaluation of the equipment that cleans the reticle R in this way is generally done by visually inspecting the reticle after cleaning, or by using an exposure device to test print and develop the reticle pattern on the wafer, and then transferring it. This is done by visually inspecting the pattern on the wafer. However, visual inspection shows that 5μm
Detection of the following foreign matter is difficult, and the transfer method is limited by the transfer resolution of the exposure device, and foreign matter smaller than the resolution cannot be transferred, making inspection itself impossible. Furthermore, both evaluation methods require labor and time, and lack quantitative properties. Therefore, as it is expected that miniaturization in the manufacturing process of semiconductor devices such as ICs and LSIs and lithography processes will further advance in the future, it is important to know whether the current cleaning equipment can cope with the miniaturization and whether the cleaning equipment It was not possible to obtain information regarding areas that needed improvement.

According to the present invention, it is possible to quantitatively evaluate a cleaning device precisely, with high precision, and in a short time. This will be explained using FIG. 16. FIG. 16 is a circuit block diagram of a photoelectric detector circuit connected to foreign object detection circuit 152. The foreign object detection circuit 152 receives photoelectric signals from a plurality of photoelectric detectors arranged to receive scattered light from a foreign object at a plurality of different positions, and in FIG. The detection circuit is shown. Scattered light from foreign objects lo
is condensed by a condensing lens 300 and sent to a photodetector, such as a photomultiplier tube (hereinafter referred to as a photomultiplier) 3
01 reaches the light receiving surface 301a. preamp 30
2 amplifies a photoelectric signal 303 corresponding to the light intensity of the scattered light lo and inputs the signal to the foreign object detection circuit 152. The high voltage generation circuit 304 is a photomal 301
At the same time, the bias voltage 305 is applied to voltages V1 and V2 (however, V2>V
1) can be switched between a low voltage and a high voltage that are amplified approximately 100 times. When the bias voltage 305 is changed, the photoelectric conversion efficiency (sensitivity) of the photomultiplier 301 changes sensitively, and when the bias voltage 305 is increased, the photoelectric signal 303 is outputted sufficiently large even if the light intensity of the scattered light becomes low. Therefore, it becomes possible to detect smaller foreign objects. Therefore, when inspecting an ordinary reticle, a voltage V1 is selected using a changeover switch 306 so that the bias voltage 305 becomes a low voltage (for example, 300 to 1500 V). In this case, the detection ability is determined to be commensurate with the cleanliness required of the reticle. For example, if we assume that there is no need to detect foreign objects that are 5 μm or smaller on the reticle because they are not transferred by the exposure device, the low voltage will not be able to detect foreign objects that are 5 μm or larger. Can be matched. On the other hand, when evaluating the cleaning apparatus, a voltage V2 is selected by the changeover switch 306 such that the bias voltage 305 becomes a high voltage approximately 50 to 200 V higher than the low voltage (300 to 1500 V). Then, the foreign object detection circuit 152 tests whether there is a foreign object by detecting whether the magnitude of the photoelectric signal is larger than a predetermined slice level.

Now, in order to evaluate the cleaning device, after cleaning the reticle, the reticle is transferred to the foreign object inspection device 3.
Transport to. Then, the voltage V2 is selected by the changeover switch 306, and foreign matter inspection is performed with the bias voltage 305 set to a high voltage. This makes it possible to detect foreign objects with higher sensitivity than usual, for example 5 μm.
Adhesion of foreign matter of the following sizes can also be easily inspected.
Therefore, as a result of the inspection, the cleaning ability of the cleaning device is evaluated by determining the size or amount of foreign particles remaining on the reticle. In addition, if the scattered light from the pattern formed on the reticle causes false detection of a foreign object, or if the foreign object inspection device has a low ability to separate and detect the scattered light from the pattern and the scattered light from the foreign object, By using a glass substrate on which no pattern is formed, so-called blank glass, instead of a reticle, even smaller foreign objects can be inspected without false detection, and the evaluation of cleaning equipment becomes more precise.

Here, the bias voltage 305 of the photomultiplier 301 is made variable in order to make the sensitivity of the photoelectric detection circuit variable, but the same effect can be obtained by making the amplification factor of the preamplifier 302 variable. Furthermore, the same effect can be obtained by varying the power density of the laser beam that irradiates the reticle or blank glass. In any case, by inspecting the cleaned reticle or blank glass with a higher foreign matter detection ability than usual, cleaning ability and cleaning effectiveness can be confirmed. Also, if the bias voltage, amplification factor, or power density is 2
A rotary switch may be provided so that the switching can be performed in more than one step according to need.

In this way, it is possible to detect foreign substances that cannot be detected visually or by the transfer method, so that accurate and quantitative evaluation of the cleaning device (such as how much cleaning ability it has) can be efficiently performed. It is also effective in checking the cleanliness inside the cleaning device. For example, when the foreign matter removal ability of the rotating brush in the cleaning tank 7 decreases and more foreign matter remains on the reticle, it is determined that the brush has worn out. This also has the advantage of making it easy to know when it is time to replace the brush.

(Effects of the Invention) As described above, according to the present invention, the substrate (reticle or photomask) in the case can be taken out without manual intervention, and the foreign object inspection and cleaning can be automatically carried out. This eliminates the need for direct handling by humans, which is the most problematic aspect of cleaning, and results in reticles and photomasks that are free of foreign substances. Another advantage is that the ability of the cleaning equipment can be evaluated because foreign matter inspection is performed immediately after cleaning. In addition, reticles and photomasks that have been completely cleaned of foreign matter are stored in a case. Therefore, if the case is attached to the exposure device and the reticle is automatically carried out and loaded to the predetermined exposure position, the possibility of causing defects due to foreign objects in manufactured ICs and LSIs will be extremely reduced. As a result, there is an advantage that the production yield of ICs and LSIs is significantly improved.
Moreover, the cleanliness of the atmosphere before transporting to IC manufacturing equipment such as exposure equipment does not have to be very high, and there is also the advantage that there is no need for large investments in production line equipment, especially air conditioning equipment.

[Brief explanation of drawings]

FIG. 1 is a plan view of an automatic cleaning device according to an embodiment of the present invention, FIG. 2 is a perspective view showing the overall arrangement of the conveyance mechanism of the automatic cleaning device, and FIG. 3 is a perspective view showing the belt drive structure. , FIG. 4 is a perspective view showing the arrangement of the reticle loading/unloading mechanism and the case, FIG. 5 is a perspective view showing the structure of the carrier 37, FIG. 6 is a partial sectional view showing the structure of the attitude changing mechanism, and FIG. 7 is a perspective view showing the structure of the arm support part 53, and FIG.
9 is a side view of FIG. 8, FIG. 10 is an end view taken along the line A-A in FIG. 8, and FIG. 11 is a view taken along the line B-B in FIG. 8. 12 is a perspective view showing the structure of the arm opening/closing mechanism, FIG. 13 is a circuit block diagram of a control system for controlling the automatic cleaning device, and FIGS. 14 and 15 are examples of operations by the control system. FIG. 16 is a circuit block diagram showing an example of a photoelectric detection circuit of a foreign object inspection device. Explanation of symbols of main parts, 1...Device body, 2...
...Clean unit, 3... Foreign object inspection device, 4...
...Attitude change mechanism, 5...Arm mechanism, 6...Arm transport mechanism, 7...Cleaning tank, 8...Rinse tank, 9
...Steam drying tank, RC...Reticle case.

Claims (1)

[Scope of Claims] 1. A mounting mechanism capable of attaching a plurality of cases for horizontally holding a substrate to be cleaned in a substantially sealed state and removably storing the board in a horizontal state; and a state in which the substrate is held substantially horizontally. a foreign matter inspection means for inspecting the presence or absence of foreign matter adhering to the surface of the substrate; a cleaning means for cleaning the substrate while holding it substantially vertically with an arm; the mounting mechanism; the foreign matter inspection means; and the cleaning means. In the substrate cleaning device, the substrate is taken out horizontally from the case mounted on the mounting mechanism, and the board is horizontally taken out from the case mounted on the mounting mechanism to the foreign object inspection means in a horizontal state. a transport mechanism for delivering the substrate by the transport mechanism; a posture change means for receiving the substrate carried by the transport mechanism in a horizontal state, and converting the received substrate to a vertical state by a rotating mechanism; a drive mechanism for vertically transferring the substrate held vertically by the cleaning means to the arm of the cleaning means; controlling a series of transport operations of the substrate by the transport mechanism, the attitude changing means, and the drive mechanism; 1. A substrate cleaning apparatus comprising: a control means. 2. The foreign matter detection means includes a photoelectric detection section that optically detects foreign matter attached to the substrate, and a sensitivity changing section that changes the detection sensitivity for the foreign matter, and the foreign matter detection means Claim 1, wherein the sensitivity changing unit is controlled so that the detection sensitivity for foreign objects is higher than usual when the object is transported to the foreign object inspection means via the posture change means and inspected. The device described in. 3. The control means includes a display member that displays the state of contamination due to foreign matter on the board inspected by the foreign matter inspection means, and returns a board whose contamination state is determined to be extreme to the case without sending it to the cleaning means. The apparatus according to claim 1, further comprising: a program. 4. The attitude changing means moves the holding part between a holding part that holds the substrate, a position for receiving the substrate horizontally taken out from the case, and a position for transferring the substrate to the arm of the cleaning means. a moving member for moving the substrate, and a holding portion held at an angle of approximately 90° with respect to the moving member for changing the posture of the substrate.
2. The apparatus according to claim 1, further comprising a rotation mechanism for rotating the apparatus. 5. The control means specifies in advance whether the substrate transferred from the case is inspected by the foreign matter inspection means and then sent to the cleaning means, or whether the substrate is sent to the cleaning means without passing through the foreign matter inspection means. An apparatus according to claim 1, characterized in that it comprises input means for. 6. The cleaning means includes a foreign matter removing member that rubs and removes foreign matter attached to the surface of the substrate, and the control means sends the substrate cleaned by the cleaning means to the foreign matter inspection means to remove foreign matter from the surface of the substrate. Claim 1, characterized in that it includes a sequence program for inspecting the remaining foreign matter, and is capable of evaluating the foreign matter removal ability of the cleaning means based on the size or amount of the remaining foreign matter. equipment. 7. The apparatus according to claim 6, wherein the time for replacing the foreign matter removing member of the cleaning means due to wear is determined based on a decrease in the foreign matter removing ability of the cleaning means.