JP4108242B2 - Transport device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To convey a semiconductor wafer in a high vacuum level between processing chambers and respective processors in a multi-chamber type processor, and hold the interior of a conveying chamber under the high vacuum level to convey a wafer, and directly connect with various kinds of vacuous processor without a buffer chamber. SOLUTION: A flow rate of a gas to be supplied to a conveying chamber 1 is controlled by a flow rate controller 14, and a flow of the gas flowing in a clearance 11 between a wafer 4 and a conveying plate 2 is set as a molecular flow or transition flow region.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a conveyance apparatus, and more particularly, to transport in a production line of the semiconductor device for performing processing using a plurality of processing devices, and the like between the respective processing chambers or between various processing devices, the semiconductor wafer under high vacuum, It relates conveyance device that can be subjected to various treatment under high vacuum.
[0002]
[Prior art]
In the production of various semiconductor devices, a method of processing semiconductor wafers in cassette units is generally performed, but a method of sequentially processing by sending semiconductor wafers that have been processed one by one to the next processing device has also been proposed. It is expected as a production method using a flow line. With regard to the transport of semiconductor wafers by this method, studies are proceeding centering on a nitrogen levitation transport method in which gaseous nitrogen is blown up from below the semiconductor wafer to float the semiconductor wafer and transport between the processing apparatuses. For example, as disclosed in Japanese Patent Application Laid-Open No. 5-21225, an apparatus using an atmospheric pressure method that floats and conveys a wafer in an atmospheric pressure is used as a conventional conveyance device using the floating conveyance method.
[0003]
[Problems to be solved by the invention]
However, since the conventional levitation transfer method in the atmospheric pressure is (1) transfer in the atmospheric pressure, when the semiconductor wafer is put into the vacuum processing chamber, the semiconductor between the vacuum processing chamber and the atmospheric chamber is used. In order to enable movement of the wafer, a buffer chamber for exhausting and venting is required. (2) In the process of exhausting and venting in the buffer chamber, dust or the like adhering to the end of the semiconductor wafer Particulates rise and become contaminated by reattaching to the surface of the semiconductor wafer. (3) It is difficult to keep the processing chamber in an ultra-high vacuum because of the gas released from the O-ring necessary to seal the buffer chamber. (4) Fine particles generated during processing and chipping are swollen by a large amount of gas (nitrogen) supplied during transportation, and adhere to the surface of the semiconductor wafer. (5) Each Since it is necessary to provide buffer chambers between the labs, the time required to pass through each buffer chamber is required, and the number of processed sheets is reduced. (6) Since the wafer is floated at atmospheric pressure, it is transported with the wafer. Since the gap between the plates becomes large and easily fluctuates, it is difficult to stop the conveyed wafer at a predetermined position with high accuracy, and (7) the cost of the processing apparatus is increased. there were.
[0004]
An object of the present invention is to solve the above-mentioned problems of conventional wafer transfer apparatuses and to transfer wafers between the processing apparatuses in a multi-chamber processing apparatus constituting a semiconductor device manufacturing line without using a buffer chamber. By providing a low-cost wafer transfer device that can be performed with high accuracy under vacuum, and can quickly make an ultra-high vacuum inside each processing chamber after wafer transfer, with a large number of processable wafers. is there.
[0005]
[Means for Solving the Problems]
Conveyance apparatus of the present invention to solve the above problem, a transfer chamber for conveying to process a wafer in place, a transfer plate for holding the wafer was provided in the transfer chamber on its A plurality of ejection holes provided in the conveyance plate that are inclined in a direction in which the wafer is to be conveyed, means for supplying the gas to the ejection holes from below to float and convey the wafer, and the conveyance chamber in conveyance apparatus at least comprising means for evacuating, by means of the exhaust while evacuating the conveying chamber is evacuated, by controlling the flow rate of the gas, flowing a gap between the carrier plate and the wafer The gas flow is characterized by comprising means for converting the gas flow into a molecular flow or a transition flow.
[0006]
That is, the wafer transfer apparatus of the present invention has a large number of ejection holes 3, sensor holes 5 and control holes in the transfer chamber 1, as shown in FIGS. 8 is provided, and a wafer 4 to be transported is placed on the transport plate 2. A gas (for example, nitrogen) is supplied to the ejection hole 3 and the control hole 8 through a gas supply chamber 12, and the product of the static pressure of the gas and the area of the lower surface of the wafer 4 is balanced with the gravity of the wafer 4. Sometimes the wafer 4 rises.
[0007]
As is apparent from FIG. 2, the ejection hole 3 is provided so as to be inclined with respect to the lower surface of the wafer 4 and the conveyance direction 30 (for example, about 22 ° with respect to the perpendicular from the lower surface). Is transported in the transport direction 30 by the pressure of the gas ejected from the ejection hole 3.
[0008]
The transfer chamber 1 is divided into an upper vacuum chamber 10 and a lower gas supply chamber 12 by the transfer plate 2. As apparent from FIG. 2, the flow rate of the gas supplied to the gas supply chamber 12 is extremely reduced by the flow rate controller (mass flow controller) 14 and is controlled with an accuracy of ± 1%. 11 can be made very small, but can be kept almost constant with high accuracy. For example, if the pressure of the gas is set to 70 Pa (0.5 Torr) using the flow rate controller 14, the gap 11 is maintained at 0.018 mm ± 0.0018 mm.
[0009]
As is well known, when the relationship h << λ is established between the gap h and the mean free path λ of the flowing gas, the gas flow is called Knudsen flow or molecular flow, and this molecular flow and viscosity become a problem. A flow in the middle of a normal viscous flow is called a transition flow or intermediate flow. The flow rate of gas in the case of molecular flow or transition flow is 10 ⁻⁴ to 10 ⁻³ of viscous flow, which is much less. In addition, the gas flow through the gap 11 between the wafer 4 and the transport plate 2 below is generally described in V. 20 (12) 525, 1970. For example, a gas having a pressure of 70 Pa flowing through the gap of 0.018 mm is determined to be a molecular flow from this equation.
[0010]
In the present invention, the gap 11 can be reduced by reducing the gas flow rate by the flow rate controller 14. For example, if the pressure of the gas supplied to the gap 11 is set to 70 to 700 Pa, the gap 11 is kept extremely small as 0.018 to 0.05 mm. If the pressure of the gas supplied to the gap 11 is 700 Pa or less and the gap 11 is 0.05 mm or less, the flow state of the gas flowing through the gap 11 becomes a molecular flow or a transition flow (intermediate flow). By evacuating with the turbo molecular pump 18, the degree of vacuum in the processing chamber 1 is kept high and can be directly connected to various vacuum processing apparatuses without using the buffer chamber. That is, in general, high vacuum .133 to 1.3 × ¹⁰ -5 Pa, the following 1.3 × ¹⁰ -5 Pa is called an ultra-high vacuum, in the present invention, as described above, the gap 11 By setting the pressure of the supplied gas to 70 to 700 Pa, the gas flow through the gap 11 becomes a molecular flow or a transition flow. For this reason, for example, by evacuating with a turbo molecular pump or the like, the inside of the transfer chamber 1 easily becomes an ultra-high vacuum of 1.3 × 10 ⁻⁵ Pa or less, and processing under an ultra-high vacuum such as sputtering is performed. Can be directly connected to various processing chambers for the desired processing.
[0011]
On the other hand, in the conventional atmospheric pressure method in which the wafer is floated and conveyed at atmospheric pressure, ± 1% of the atmospheric pressure (760 Torr = 10 ⁵ Pa) is ± 10 ³ Pa. Is ± 0.068 mm, and the gap 11 cannot be 0.2 mm or less. Therefore, in the conventional atmospheric pressure method, a large amount of gas is supplied without flow control without using a controller, the gap is increased to about 0.5 mm, and the supplied large amount of gas is vacuum pumped. It is difficult to keep the degree of vacuum in the transfer chamber high.
[0012]
As described above, in the present invention, the transport plate 2 has the ejection holes 3 for floating and transporting the wafer 4, the sensor holes 5 for stopping the transported wafer 4 at predetermined positions, and the wafer 4. Is provided with a control hole 8 for preventing lateral displacement from the conveying direction 30. When the wafer 4 floats and is transported, gas is simultaneously supplied to all of the ejection holes 3 and the control holes 8 and exhausted by the turbo molecular pump 18 to keep the interior of the transport chamber 1 at a high degree of vacuum. The gap 11 depends on the pressure of the gas below the wafer 4. In the present invention, the flow rate of the gas supplied to the gas supply chamber 12 is extremely reduced by the flow rate controller 14 as described above, and ± 1 Therefore, the extremely small gap 11 is maintained with high accuracy, and the wafer 4 is stably floated and conveyed.
[0013]
Further, in the case of the above-described conventional transfer apparatus in which the wafer is transferred at atmospheric pressure, the central portion of the lower portion of the wafer is brought into a vacuum state by the gas ejection from the lower periphery of the wafer 4. The atmospheric pressure applied prevents the wafer from rising. However, in the case of the present invention, since the upper part of the wafer 4 is vacuum, even if the lower part of the wafer 4 is depressurized, such extra force is not applied to the upper part of the wafer 4, and the wafer 4 is lifted. There is no fear of being disturbed.
[0014]
As a result of these, according to the present invention, the amount of gas required for the floating and transport of the wafer is 10 ⁻⁴ or less in the molecular flow region, compared to the conventional method used in the gas viscous flow region, In the transition flow region, it is much less, ^10-3 or less.
[0015]
In a normal case, the conveyance speed of the wafer 4 is preferably 0.1 to 1 m / s, and the acceleration is preferably 0.1 to 1 m / s ² . Further, for example, keep the roughness _{R a} of the finish of the inner surface of the transfer chamber 2 1.6s, if 3.2s the maximum height _{R max} of the mean, the wafer 4 in the floating state while maintaining a small gap 11 It is easy. Furthermore, if the contact area between the wafer 4 and the transport plate 2 is large when the wafer 4 is on the transport plate 2 without floating, the wafer 4 may be contaminated. If the contact surface 6 is provided to reduce the contact area between the two, such contamination of the wafer 4 can be easily prevented.
[0016]
Conveyance apparatus of the present invention shifts a means for detecting the position of the conveyed the wafer, based on a signal from means for detecting the position upward to lift the stop and the wafer of the wafer Means can be provided. The means for detecting the position of the wafer, it is practically preferable to use the conveyance optical sensor arranged below the formed sensor holes and the sensor hole at a predetermined position of the plate.
[0017]
In addition, the wafer conveyance device of the present invention includes means for decelerating the conveyed wafer, and detects the position of the wafer decelerated by the decelerating means by means for detecting the position of the wafer. be able to. As a means for decelerating the wafer, an electrostatic chuck is preferable. As described above, in the present invention, since the gap 11 between the wafer 4 and the transport plate 2 is extremely small, the transported wafer 4 is easily decelerated by the electrostatic chuck 7 disposed below the wafer 4. be able to. When detecting the position of the wafer 4 that has been transported, detection of the position after the wafer 4 is decelerated in this way can be detected with much higher accuracy than when detection is performed without deceleration. Needless to say.
[0018]
The electrostatic chuck 7 is always energized during conveyance of the wafer 4, the wafer 4 decelerated by the electrostatic chuck 7 reaches a predetermined position, and the edge of the front end in the conveyance direction 30 of the wafer 4 is a sensor hole. 5, the fiber light sensor 15 detects that the wafer 4 has reached a predetermined stop position, and a predetermined signal is emitted from the fiber light sensor 15. By this signal, the linear field through 13, the push-pull solenoid 17 and the control device 16 with fast response are operated, and the wafer 4 is attracted, stopped and raised. Thereby, the wafer 4 is stopped at a predetermined position with high accuracy.
[0019]
For example, the wafer 4 conveyed at a conveyance speed of 0.1 to 1 m / s is decelerated to a speed of about 1/3 by the electrostatic chuck 7. When the edge of the tip of the decelerated wafer 4 reaches above the sensor hole 5, it is detected by the fiber light sensor 15 with an accuracy of about 0.03 mm, and a signal is emitted from the fiber light sensor 15. By this signal, the wafer 4 is attracted to the electrostatic chuck 7 to stop the conveyance, and is moved upward by the electrostatic chuck 4, the linear field through 13, the push-pull solenoid 17 and the controller 16. The responsiveness of the control device used in this case can be 3 ms or less, and the wafer 4 stops at a position within 0.2 mm from the position of the wafer 4 at the time when a signal is emitted from the fiber light sensor 15. When the orientation flat of the wafer 4 becomes close to the end of the transfer chamber 2 (upper and lower ends in FIG. 1), the position of the edge of the front end of the wafer 4 changes slightly. The wafer 4 can be stopped with an accuracy within 2 mm.
[0020]
In the above-described conventional apparatus, the wafer is stopped using Bernoulli's theorem at the stop position, so a large amount of gas is required and cannot be used in a vacuum. In addition, since the gap between the wafer and the conveyance plate is large, it is difficult to decelerate and attract the wafer with high accuracy by the electrostatic chuck, and it is difficult to stop the conveyed wafer at a predetermined position with high accuracy. Met.
[0021]
However, in the present invention, unlike the above-described conventional apparatus, a large amount of gas is not used, and the gap between the wafer and the conveying plate is extremely small. Therefore, deceleration and adsorption by the electrostatic chuck are extremely easy, and the wafer can be stopped at a predetermined position with a much higher accuracy than the conventional apparatus.
[0022]
As the electrostatic chuck 7, for example, the bipolar type shown in FIG. 3 can be used. Since the protruding point contact body 19 makes point contact with the back surface of the wafer 4 and the wafer 4 is attracted, the electrostatic attracting body 20 is not attracted to the entire back surface of the wafer 4 and the electrostatic attracting body 20 There is no possibility that the wafer 4 is contaminated by the entire surface contact. The wafer 4 raised upward is transported to a processing chamber (not shown) by the transport mechanism 9 and subjected to a predetermined process.
[0023]
The center of the wafer 4 transported in the transport direction 30 is connected to one end and the other end (the upper end and the lower end in FIG. 1) of the transport plate 2 parallel to the transport direction 30 of the wafer 4. A plurality of control holes 8 inclined toward the line are respectively formed in the transport direction 30.
[0024]
In other words, if the wafer 4 is lifted and transported by gas, the wafer 4 being transported may deviate from the transport direction 30 and collide with the interior of the transport chamber 2 and be damaged. However, in the present invention, gas is ejected from the plurality of control holes 8 in the direction of the center line of conveyance. Therefore, when the end of the wafer 4 comes out of the transport direction 30 and comes to the upper part of the control hole 8, the wafer 4 is returned to the center by the gas ejected from the control hole 8 toward the center line. Collisions with the interior of the chamber 2 are prevented.
[0025]
A preferable result can be obtained if the diameter of the control hole 8 is substantially equal to the mean free path of the gas in the vicinity of the blowing portion of the control hole 8. That is, when a viscous flow is ejected from the hole at a pressure equal to or higher than the atmospheric pressure, the gas is ejected from the control hole 8 as a radial gas ejection flow 22 as shown in FIG. For this reason, even if the end of the wafer 4 reaches the upper part of the control hole 8, it is canceled out by the gas ejected from the gap 11 at the lower part of the wafer 4 through the ejection hole 3, and the wafer 4 is moved to the center. It cannot be returned with high accuracy and may collide with the end of the transfer chamber 2.
[0026]
However, in the present invention, since the diameter of the gas control hole 8 is set to a value close to the mean free path of the gas in the vicinity of the blowing portion, the gas from the control hole 8 is released as the molecular beam-like jet flow 21. . Therefore, when the force is much greater than that in the case of the radial gas jet flow 22 and the wafer 4 deviates from the conveyance direction 30 and the end of the wafer 4 reaches a part of the control hole 8, the wafer 4 is moved. The collision with the transfer chamber 2 is prevented by returning toward the center. For example, since the mean free path λ is 0.098 mm when the diameter d of the control hole 8 is 1 mm, the length is 5 mm, and the supply pressure of gas (nitrogen) is 70 Pa, the complete molecular beam (d ≦ λ) However, unlike the case of viscous flow, the gas beam has a molecular beam shape, and the collision between the wafer 4 and the end of the transfer chamber 1 is effectively prevented.
[0027]
It is important to remove fine particles such as dust adhering to the wafer. Therefore, the wafer conveyance device of the present invention can include means for irradiating the wafer with an electron beam or ultraviolet light and electrostatic adsorption means for adsorbing charged particles on the wafer. That is, as shown in FIG. 5, a secondary electron beam source or an ultraviolet ray source 24 is used to irradiate the wafer 4 in the vacuum chamber 10 of the transfer chamber 1 with an electron beam or an ultraviolet ray, and a high voltage power source 23 is used. A potential of 10 kV or less is applied to the electrostatic adsorption mechanism 26, and the charged fine particles adhering to the surface of the wafer 4 are adsorbed and removed by the electrostatic adsorption mechanism 26. The fine particles are effectively removed by applying an electrostatic potential that is higher than the adhesion force by Van der Waals force or electrostatic force. If the gas pressure in the vacuum chamber 10 is kept at a high vacuum of, for example, 6 × 10 ⁻² Pa, there is no fear of discharge. As shown in FIG. 5, it is preferable to provide a shield 25 between the secondary electron beam source / ultraviolet light source 24 and the electrostatic adsorption mechanism 26 to prevent interference.
[0028]
Furthermore, the wafer conveyance device of the present invention comprises a disk-shaped gas ejection plate having a gas ejection hole, which is disposed at a predetermined position in the conveyance chamber, and means for rotating and moving the disk-shaped gas ejection plate. be able to.
[0029]
That is, when forming a flow line in the production of a semiconductor device, it is essential to change the direction of the wafer 4 and move it up and down. An example of means for this will be described with reference to FIG. The wafer 4 stopped at a predetermined position is placed on a disk-like gas ejection plate 27 in which the ejection holes 3 are formed, and is directed in a desired direction using a rotation / linear field through 28 and a rotation motor 29. , Moved further up and down. Next, gas is ejected from the gas ejection holes 3 formed in the gas ejection plate 27, and the wafer 4 is conveyed to a desired processing apparatus. In this way, it is possible to easily change the direction and move the wafer 4 under high vacuum.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
Example 1
In this embodiment, the wafer shown in FIGS. 1 and 2 is used to carry a wafer at a high degree of vacuum. An 8 ″ wafer 4 weighing 56 g is placed on the conveying plate 2, and an area for floating (the area of the lower surface of the wafer 4 in contact with the gas accumulated under the wafer 4) is applied to the lower surface of the wafer 4 at 177 cm ² . When the pressure of the nitrogen applied was 70 Pa, the gap 11 between the wafer 4 and the conveying plate 2 was 0.018 mm, and a flying pressure of 123 gf was obtained, and 293 ° of the nitrogen introduced into the gap 11 at this time The mean free path in K is λ = 9.3 × 10 ⁻⁵ m, Knudsen number K _n = λ / h = 5.2 (h is the size of the gap 11), and it is confirmed that a molecular flow is formed. (When K _n <0.005, viscous flow, 5> K _n > 0.005, transition flow, and when K _n > 5, molecular flow).
[0031]
The thrust of conveyance of the wafer 4 was 0.58 gf, and the conveyance speed was 0.1 m / s. The acceleration was estimated to be 0.1 m / s ² . The flow rate of the gas (nitrogen) was adjusted to 1.2 × 10 ⁻³ Pa · m ³ / s by the flow rate controller 14. Exhaust was performed using a turbo molecular pump 18, and the exhaust speed was 200 l / s.
[0032]
In this case, the degree of vacuum in the transfer chamber 1 deteriorated to 6 × 10 ⁻² Pa during transfer of the wafer 4, but when the supply of nitrogen was stopped, the degree of vacuum quickly recovered to 1 × 10 ⁻⁴ Pa, and the wafer The degree of vacuum in the processing chamber (not shown) in which 4 is transferred from the transfer chamber 1 via a slit valve (not shown) is also quickly restored to 1 × 10 ⁻⁶ Pa, and the subsequent processing is performed without any trouble. I was able to.
[0033]
Example 2
In this embodiment, the transferred wafer is stopped at a predetermined position and moved to the upper part. When the wafer 4 having a weight of 56 g and a diameter of 8 ″ is transported at a speed of 0.1 m / s, the inertial force is about 0.6 gf. The speed of the wafer 4 transported at the above speed is shown in FIG. Was reduced to 0.03 m / s by the electrostatic chuck 7 having an adsorption force of about 1 gf.
[0034]
After the position of the decelerated wafer 4 is detected by the fiber optical sensor 5, the control system 16 is immediately operated, and the electrostatic chuck 7 is raised to the position indicated by the electrostatic chuck 7 'by the push-pull solenoid 17, The upper wafer 4 was raised to the position of the wafer 4 '. The time required from the detection by the fiber light sensor 5 to the response of the control system 16 at this time was 0.1 ms, and the time until the response of the push-pull solenoid 17 was 2 ms. The distance that the wafer 4 has moved in the conveyance direction during a total of 2.1 ms is 0.13 mm from the detection position (sensor hole 5), and is stopped at a position sufficiently smaller than the target value of 0.2 mm according to the present invention. It was confirmed that it can be used for practical use.
[0035]
【The invention's effect】
As is clear from the above description, according to the present invention, the amount of gas introduced is extremely reduced by the flow controller and exhausted by the high vacuum pump, so that it is easy to make the transfer chamber high in vacuum. It is. Therefore, it becomes possible to transport wafers in a high degree of vacuum between the processing chambers and various processing apparatuses constituting the multichannel processing apparatus, and various vacuum processing chambers and various vacuum processing apparatuses can be used without using a buffer chamber. Can be connected directly. In addition, since the gap between the wafer and the transport plate is small, it is easy to decelerate and attract the transported wafer by the electrostatic chuck, and the wafer is stopped at a predetermined position with much higher accuracy than before. It can be used for the next treatment. Therefore, even when all process processes are performed in a high vacuum atmosphere in the future, the wafer can be easily transferred between the process chambers or the process apparatuses according to the present invention.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an example of a planar structure of the present invention.
FIG. 2 is a diagram for explaining an example of a cross-sectional structure of the present invention.
FIG. 3 is a cross-sectional view showing an example of an electrostatic chuck used in the present invention.
FIG. 4 is a cross-sectional view for explaining the operation of a control hole.
FIG. 5 is a cross-sectional view for explaining dust removal by electrostatic adsorption.
FIG. 6 is a cross-sectional view for explaining rotation and vertical movement of a wafer.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Conveying chamber, 2 ... Conveying plate, 3 ... Ejection hole 4, 4 '... Wafer, 5 ... Sensor hole, 6 ... Point contact surface, 7, 7' ... Electrostatic chuck, 8 ... Control hole, 9 ... Conveyance Mechanism: 10 ... Vacuum chamber, 11 ... Gap, 12 ... Gas supply chamber, 13 ... Linear field through, 14 ... Flow rate controller, 15 ... Optical fiber sensor, 16 ... Controller, 17 ... Push-pull solenoid, 18 ... Turbo molecule Pump, 19 ... Point contact body, 20 ... Electrostatic adsorber, 21 ... Molecular linear gas jet flow, 22 ... Radial gas jet flow, 23 ... High voltage power source, 24 ... Secondary electron source / ultraviolet light source, 25 ... Shield, 26 ... Electrostatic adsorption mechanism, 27 ... Gas ejection plate, 28 ... Rotation / linear field through, 29 ... Rotation motor, 30 ... Conveying direction.

Claims (10)

A transfer chamber for transferring a wafer to be processed to a predetermined place; a transfer plate for holding the wafer provided in the transfer chamber; and the transfer plate inclined in a direction to transfer the wafer a plurality of the ejection holes, and means for transporting the floating of the wafer by supplying a gas from below the jetting hole, feed transportable to at least comprising means for evacuating the conveying chamber device provided in the above by the exhaust to means while evacuating the conveying chamber is evacuated, it comprises means for the molecular flow or transitional flow the flow of the gas flowing through the gap between the carrier plate and the wafer by controlling the flow rate of the gas conveyance equipment you, characterized in that. Pressure of the gas supplied to the gap 70Pa or more, conveyance device according to claim 1, characterized in that not more than 700 Pa. 3. A means for detecting the position of the transferred wafer and a means for moving the wafer upward based on a signal from the means for detecting the position. conveyance device according to. The means for detecting the position of the wafer includes a sensor hole formed at a predetermined position of the transport plate and an optical sensor disposed below the sensor hole . conveyance equipment. A means for decelerating the transferred wafer is provided, and the position of the wafer decelerated by the means for decelerating the wafer is detected by means for detecting the position of the wafer. conveyance apparatus according to claim 3 or 4. Conveyance apparatus the means for decelerating the wafer according to claim 5, characterized in that the electrostatic chuck. A plurality of control holes inclined toward a line connecting the centers of the wafers transported in the transport direction are respectively provided at one and the other end of the transport plate parallel to the transport direction of the wafer. conveyance device according it to any one of claims 1 to 6, characterized in being formed respectively. From the control hole, conveyance device according to claim 7, molecular linear jet flow is characterized in that it is released. Means for irradiating an electron beam or ultraviolet rays to the wafer feeding transportable according to any one of claims 1 to 8, characterized in that it comprises a electrostatic adsorption means for adsorbing microparticles charged up on the wafer apparatus. The gas ejection plate having a gas ejection hole disposed at a predetermined position in the transfer chamber and means for rotating and moving the gas ejection plate up and down are provided. The conveying apparatus as described.

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