JPH10242235A - Substrate carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the vacuum holding force from deteriorating irrespective of the attitude of a substrate and to surely vacuum-support and carry the substrate. SOLUTION: First/second vacuum holes 4a, 4b at a substrate-supporting face 4 communicate with first/second vacuum passages 4a2 , 4b2 having restorations 4a3 , 3b3 to increase the resistances of the passages 4a2 , 4b2 enough to block a large quantity of air from flowing therein if one of the holes opens. This surely suppresses the vacuum force from deterioration to surely vacuum- support and carry a substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate transfer apparatus for transferring a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a substrate for an optical disk, and the like (hereinafter simply referred to as a substrate). In particular, the present invention relates to a technique for transporting a substrate while supporting it by suction.

[0002]

2. Description of the Related Art As a conventional substrate transfer apparatus of this type, there is, for example, one shown in a plan view of FIG. This apparatus includes, for example, a support arm 100 that sucks and supports a substrate W such as a semiconductor wafer, and transports the substrate W by driving the support arm 100 forward and backward or up and down by a driving unit (not shown). The support arm 100 has an arc-shaped substrate support surface 104 extending from a base end portion 102, and a suction port 106 is formed on the upper surface of the substrate support surface 104. A suction passage 108 communicating with the suction port 106 is formed in the base end portion 102, and the suction passage 108 is sucked by a vacuum pump (not shown) to
4, the substrate W is supported by suction.

[0003]

However, the prior art having such a structure has the following problems. That is, the substrate W such as a semiconductor wafer generally has an orientation flat OF which is an arc-shaped notch as shown in FIG. 9 and a notch (not shown) which is a V-shaped notch. It is. However, depending on the posture of the substrate W, as shown in FIG.
Is located above the suction port 106, and the suction port 106 may be open without being completely closed. In such a case, a suction leak in which a large amount of air flows in from a portion indicated by hatching in the drawing occurs, and the suction force is extremely reduced, so that there is a problem that the substrate W cannot be strongly suction-supported. . When the support arm 100 is driven and the substrate W is transported in such a state that the substrate W can be attracted and supported only by a weak force, the substrate W
May fall and be damaged.

[0004] In addition to the above-mentioned notch, the substrate W may be damaged during processing or transport, and a part thereof may be damaged. When transferring the substrate W having such a defect, even if the posture of the substrate W is controlled and the substrate W is supported on the substrate supporting surface 104 in a posture that does not cause the above-described inconvenience due to the orientation flat OF, for example. If the missing portion is located above the suction port 106, the same problem as described above may occur.

The present invention has been made in view of such circumstances, and has a plurality of suction ports and suppresses a suction leak of each suction port, so that the suction force is independent of the posture of the substrate. It is an object of the present invention to provide a substrate transfer apparatus capable of suppressing a decrease in the thickness and reliably transporting the substrate while sucking and supporting it.

[0006]

The present invention has the following configuration in order to achieve the above object. That is, the substrate transfer device according to claim 1 includes a support unit that supports the substrate, and a drive unit that moves the support unit, and the support unit that supports the substrate is moved by the drive unit. In a substrate transfer device for transferring a substrate,
The support means includes a plurality of suction ports formed for sucking and supporting the substrate, and a suction passage communicating with the suction port and having a throttle formed in a part thereof. It is.

[0007] The substrate transfer device according to the second aspect of the present invention,
2. The substrate transfer device according to claim 1, wherein the support means has a substrate support surface for supporting the substrate, and includes a support arm extending from a base end, and the suction port is provided on the substrate support surface. It is characterized by being formed in.

[0008] The substrate transfer device according to the third aspect of the present invention,
3. The substrate transfer device according to claim 2, wherein the substrate support surface is formed in an arc shape with an open end, and is brought into contact with only a peripheral portion of a lower surface of the substrate. .

Further, the substrate transfer device according to claim 4 is
2. The substrate transfer apparatus according to claim 1, wherein the support unit includes a plurality of support members that support a plurality of end portions of the substrate, and the suction port is formed at a tip end of the support member. It is assumed that.

[0010] Further, according to a fifth aspect of the present invention, there is provided a substrate transfer apparatus comprising:
5. The substrate transfer device according to claim 1, wherein a flow path cross-sectional area of the throttle is 0.5 to 1.2 mm ^2, and a length of the throttle is 3 to 8 mm. 6. It is.

[0011]

The operation of the first aspect of the invention is as follows. Since a plurality of suction ports are formed in the support means, a cutout portion or a defective portion such as an orientation flat formed on the substrate is located at one of the suction ports, and a part of the suction port is opened without being closed. Even if you leave it
Other suction ports are closed by the substrate. At one portion of the suction passage communicating with each of the plurality of suction ports, a large resistance (reduced conductance) is formed at each of the narrowed portions because a small throttle having a small cross-sectional area (or open area) is formed in the flow passage. As a result, it is possible to suppress a suction leak in which a large amount of air flows into the suction port that is left open. Therefore, it is possible to suppress the influence of the suction leak received by the closed suction port, and it is possible to transport the substrate by the supporting unit moved by the driving unit in a state where the suction force is suppressed from being reduced.

According to the second aspect of the present invention, the support means is a support arm having a substrate support surface extending from the base end, and a plurality of suction ports are formed in the substrate support surface. When the substrate is suction-supported on the substrate support surface, even if the notch portion or the deficient portion opens any of the suction ports, the influence of suction leakage received by the other suction ports can be suppressed.

According to the third aspect of the present invention, the substrate support surface of the support arm is formed in an arc shape with an open end, and the substrate support surface comes into contact only with the peripheral portion of the lower surface of the substrate. Thus, when the substrate is transported, only the peripheral portion of the lower surface of the substrate is suction-supported, and the contact area can be reduced. Therefore, contamination of the lower surface of the substrate can be minimized.

According to the fourth aspect of the present invention, since the supporting means includes the supporting member for sucking and supporting a plurality of positions at the end of the substrate by the suction port, the supporting means is cut off when sucking and supporting the substrate. Even if the notched portion or the missing portion opens one of the suction ports, it is possible to suppress the influence of the suction leak received by the other suction ports formed at the end of the support member.

According to the fifth aspect of the present invention, the degree of suppression of suction leakage greatly changes depending on the magnitude of resistance (or conductance) generated at the throttle portion. That is, if the cross-sectional area (or opening area) of the flow path of the throttle is too small or the length of the throttle is too long, the resistance of the flow path becomes too large (or the conductance becomes too small), and the attraction force is obtained. Even so, the ON / OFF time of the adsorption becomes long, and the processing time is wasted. On the other hand, if the cross-sectional area of the flow path is too large or the length is too short, the resistance of the flow path becomes too small (or the conductance becomes too large), and a large amount of air is allowed to flow. Suction leakage cannot be suppressed. Therefore, by forming an aperture having a flow path cross-sectional area (opening area) of 0.5 to 0.8 mm ² and a length of 3 to 8 mm, the resistance (or conductance) of the flow path is made appropriate. be able to. Therefore, while exerting an appropriate suction force in a state where all the suction ports are closed, a suction force enough to suck the substrate with the other suction ports even when some of the suction ports are opened is generated. be able to.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. <First Embodiment> A substrate transfer apparatus according to the first embodiment will be described with reference to FIGS. FIG. 1 is a plan view showing a schematic configuration of the substrate transfer apparatus according to the embodiment, and FIG. 2 is a side view thereof.

In FIG. 1, reference numeral 1 denotes a support arm for adsorbing and supporting a circular substrate W such as a semiconductor wafer or the like. The movable arm 20 is configured to be movable in the horizontal direction (left and right) above the base 10. Mounted on top. A guide rail 11 is fixed to the upper surface of the base 10 via a rail base 12 by screws along the left-right direction in the drawing. Note that the support arm 1 corresponds to the support means of the present invention.

A first driven pulley 13 is supported on one end side (right side in the figure) of the rail base 12 around a horizontal axis, and a mounting member erected in parallel with the guide rail 11 on the other end side. 14, the second driven pulley 15 and the driven pulley 1
6 is supported around a horizontal axis. The first / second driven pulleys 13 and 15 have substantially the same bearing position in the height direction, and only the driving pulley 16 is set at a higher position than those. First / second driven pulley 13,
A wire 17 is stretched between the wires 15, and an upper portion thereof is wound around a driving pulley 16 which is driven to rotate by an electric motor 18.

A lower portion of the wire 17 is provided with a movable base member 21 slidably fitted on the guide rail 11.
Is fixed to the overhang 21a. Movable base member 21
A U-shaped frame member 22 is provided upright, and a suction tube (not shown, for example, having an inner diameter of 4 m)
m, length 3m), a spacer 23 having a suction hole 23a on the side surface, a communication hole 23b communicating with the suction portion 23a on the upper surface, and a mounting hole 23c for fixing the support arm 1 by screwing. Is attached. One end of a suction tube (not shown) is attached to the suction unit 23a. One end is attached to a mounting bracket 22a that is attached to the inner surface of the frame member 22 and protrudes toward the suction unit 23a. Stand 1
The suction tube is inserted into the flexible protection member 24 attached to the base member 0, and the other end is attached to a vacuum pump (not shown) via the base 10.

When the above-mentioned electric motor 18 is driven, the movable base member 21 to which the wire 17 is fixed by the overhang 21a is moved together with the movement of the wire 17 stretched over the first and second driven pulleys 13 and 15. It slides along the guide rail 11. Then, the movable table 20 moves in the left-right direction in the drawing together with the support arm 1 attached to the upper portion, and conveys the substrate W sucked and supported by the support arm 1. Therefore, the guide rail 11 and the first
/ Second driven pulleys 13 and 15, driving pulley 16,
The wire 17 and the electric motor 18 correspond to a driving unit of the present invention.

Next, the support arm 1 will be described in detail with reference to FIGS. 3 is a plan view of the support arm 1, FIG. 4 is a side view thereof, FIG. 5 is a view seen from below, and FIG. 6 is a sectional view taken along line AA of FIG.

The support arm 1 has an arc-shaped support portion 3 extending from a thin plate-like base end portion 2 and having an open distal end portion. The support portion 3 has a substrate support surface 4 whose upper surface is formed slightly thicker than the base end portion 2, and a tongue-shaped support arm (not shown) that advances and retreats from a direction perpendicular to the direction in which the support arm 1 moves. 3a for avoiding interference at the time of delivery
Is formed near the tip on one end side. Two suction ports, a first suction port 4a and a second suction port 4b, are formed on the substrate support surface 4. The first suction port 4a is formed from the vicinity of the base end 2 to the vicinity of the concave portion 3a, and the second suction port 4b is formed from the vicinity of the base end 2 to the vicinity of the tip of the support portion 3. In addition, as shown in FIG. 1, the substrate W is held in such a posture that the orientation flat OF is located on the base end 2 side.
Is preferably formed so that the orientation flat OF is not positioned above the first suction port 4a and the second suction port 4b.

The first / second suction ports 4a, 4b are respectively formed with vertical holes 4a ₁ , 4b ₁ formed in the vertical direction on the base end 2 side.
Thereby, it communicates with the shallow groove 5 formed on the back surface of the base end 2. From the side surface of the base end portion 2 where the open end side of the U-shaped hole 6 for screwing the support arm 1 to the spacer 23 is located, a suction horizontal hole 7 communicating with the shallow groove 5 is formed. A closing member 7 b is fitted on the side surface of the base end 2, and a suction hole 7 a communicating with the back surface of the base end 2 is formed at a part thereof. The shallow groove 5 has a depth of about 1 mm, for example.

The first suction passage 4a ₂ and the second suction passage 4b in shallow 5 communicating with the respective longitudinal hole 4a _1, 4b _1
2 are formed, and these are the first suction ports 4 described above.
a and the second suction port 4b. Also, the first
Suction passage 4a ₁ and the second suction passage 4b ₂ is in communication with both the suction channel 8, the suction through the communication hole 8a that communicates with the lateral hole 7 formed in the U-hole 6 side and the suction path 8 It communicates with the hole 7a. As shown in FIG. 6, the dimensions of the first / second suction passages 4a ₂ and 4b ₂ are, for example, depth B = 2 m.
m and the width C = 6 mm.

At one portion of the first / second suction passages 4a ₂ , 4b ₂ , there are apertures 4a ₃ , 4a ₃ having a small cross-sectional area (opening area).
4b ₃ is formed. These apertures 4a ₃ and 4b ₃
The dimensions of the first and second suction ports 4a and 4b are as follows.
The vertical holes 4a ₁ , 4b ₁ and the first / second suction passages 4a ₂ , 4
and b _2, a lateral hole 7, and the suction hole 7a, a suction passage 8, a contact hole 8a, and dimensions, such as the suction portion 23a and the vacuum pump suction tube connecting the (not shown) and (not shown), vacuum This is set in consideration of the suction force of the pump, the size of the substrate W, and the like. As an example, as shown in FIGS. 3 and 6, the drawing length l = 5 mm and the depth a = 0.
8 mm and its width b = 1 mm.

A thin plate-shaped lid member 9 is fixed to the shallow groove 5 in which the first / second suction passages 4a ₂ and 4b ₂ are formed. As shown in FIG. 1, the support arm 1 is mounted by mounting screws 25 such that the suction holes 7 a of the base end 2 coincide with the communication holes 23 b of the spacer 23. Therefore, the suction of the suction part 23a by the vacuum pump and the suction tube (not shown) becomes the suction force at the first / second suction ports 4a and 4b through the respective passages and holes.

Therefore, as shown in FIG. 1, when the substrate W is placed on the substrate supporting surface 4 with the orientation flat OF facing the base end 2, the first suction port 4a and the second The peripheral portion of the lower surface of the substrate W is sucked and held by the suction port 4b. Further, as described above, the first suction port 4a and the second suction port 4b are formed in the substrate support surface 4 of the support arm 1, and the first suction passages 4a ₂ and because 4a ₃ stop respectively to the second suction passage 4b _2, 4b ₃ are formed, a first suction passage 4a ₂ and the second suction passage 4b ₂
The resistance of the flow path is large (or the conductance is small). Therefore, the orientation flat OF and the defective portion of the substrate W are
Even if it is located in either one of the second suction port 4a and the second suction port 4b, it is possible to suppress a suction leak in which a large amount of air flows from the suction port. As a result, the other suction port can be suppressed from being affected by suction leakage,
A decrease in the suction force at the other suction port can be suppressed. Therefore, the substrate W can be reliably held by suction, and the inconvenience of the substrate W falling during transportation due to a decrease in the suction force can be prevented.

Further, as described above, since the supporting portion 3 is formed in an arc shape having an open end, when the substrate W is suction-supported, the substrate supporting surface 4 is formed only at the peripheral portion of the lower surface of the substrate W. The contact area can be reduced. Therefore, the contamination of the substrate W can be minimized, and the cross-contamination due to successively supporting the substrate W by suction can be prevented.

The apertures 4a ₃ and 4b ₃ described above have their flow path cross-sectional areas (a × b) set in the range of 0.5 to 1.2 mm ² and their throttle lengths l set in the range of 3 to 8 mm. Is preferred. In other words, if the cross-sectional area of the flow path is smaller than the lower limit and the throttle length is longer than the upper limit, the resistance of the flow path becomes too large (or the conductance becomes too small), and both of the first and second suction ports 4a and 4b. When the suction port is closed by the substrate W, even if suction force is obtained, ON / OF of suction is performed.
The processing time is wasted because the F time becomes long. On the other hand,
If the flow path cross-sectional area is larger than the upper limit and the constriction length is shorter than the lower limit, the resistance of the flow path becomes too small (or the conductance becomes too large), and the first / second suction ports 4a, 4b are formed.
If either one of them is left open, a large amount of air flows in therefrom, and it is not possible to suppress the suction leakage.

Next, the suction force in a state where one of the two suction ports of the support arm 1 having the above-described configuration is opened is calculated by calculation. The substrate W is an 8-inch diameter semiconductor wafer (approximately 53 g), and the calculation is performed by taking the support arm 1 configured as described above as an example to suck and support the substrate W. The opening area (2.3 cm ² ) of the first suction port 4a and the second suction port 4b described above is assumed to be the same for simplification of calculation.

First, a 1/1 / th suction tube (not shown) is used.
The combined conductance C up to the second suction ports 4a and 4b is calculated. Note that actually measured results, since the suction pressure of the suction portion 23a serving as a suction source the support arm 1 was -55kPa, p ₁ = 46kPa this suction pressure from the difference between the atmospheric pressure
Since the suction pressure of a suction pump (not shown) was -72 kPa, p ₂ was set to 29 kPa in the same manner as described above. Also, the first
/ The pressure at the outlet of the second suction ports 4a, 4b is atmospheric pressure
(p ₃ = 101 kPa).

The conductance C _T of the suction tube (inner diameter d = 4 mm, length l = 3 m) is circular, and the cross-sectional shape is circular, so if the view factor is 1349, C _T = 1349 · (d ⁴ / l) · ( _{p 1 + p 2) / 2} = 1349 · (0.004 4/3) · (46 × 10 3 + 29 × 10 3) / 2 = 4.3 × a ^{10 -3 [m 3 / s]} .

First and second suction passages 4a ₂ and 4b formed before and after the throttles 4a ₃ and 4b ₃ in the support arm 1.
_{2 The} conductances C _A1 and C _A2 of the flow path (l = 90mm × 2) including (A = 2mm, B = 6mm) are the correction coefficient K when the cross section is square.
_{Since 15} has A / B = 0.33, K ₁₅ = 0.58, and since the cross-sectional shape is square, the view factor is 1988.If C _A1 = 1988 ・ (A ² B ² / l) ・ (p ₁ + p _{3 ) / 2 · K 15 = 1988} × (0.002 2 × 0.006 2) /0.09× ((46 × 10 3 +101 × 10 3) / 2) a ^{× 0.58 = 0.136 [m 3 /} s]. Although the first and second suction passages 4a ₂ and 4b ₂ have different shapes, if they have the same shape for simplicity of calculation, CA ₂ = 0.136 [m ³ / s] as described above. .

[0034] and the suction pressure p ₁ of the suction portion 23a suction port 4a,
From the pressure p _{3 of} 4b, the diaphragms 4a ₃ , 4b ₃ (a = 0.8 mm, b = 1m
m, calculating the conductance C _of the l = 5 mm), the correction factor K ₁₅ when the cross-sectional shape of the square is at a / b = 0.8
K ₁₅ = 0.98, and the cross-sectional shape is square, so the view factor is 19
Assuming 88, C _of = 1988a ² b ² / l ・ (p ₁ + p ₃ ) / 2K ₁₅ = 1988 × (0.0008 ² × 0.001 ² ) /0.005 × ((46 × 10 ³ +101 × 10 ³ ) / 2) × 0.98 = 1.8 × 10 ^-2 [m ³ / s].

From these, the synthetic conductance C of the flow channel
Is 1 / C = 1 / C _T + 1 / C _A1 + 1 / C _A2 + 1 / C _of = 3.3 × 10 ⁻³ [m ³ / s].

When the pumping speed S of the vacuum pump is S ₀ = 50 l / min = 8.3 × 10 ⁻⁴ [m ³ / s], the pumping speed S of the flow path is: S = S ₀ C / (S ₀ + C) = 8.3 × 10 ^-4 × 3.3 × 10 ^-3 /(8.3 × 10 ^-4 + 3.3 × 10 ^-3 ) = 6.6 × 10 ^-4 [m ³ / s].

[0037] From the pressure p ₃ Prefecture in the suction pressure p ₂ and the suction port of the vacuum pump, when calculating the amount of leakage Q _l by the support arms _{1, Q l = C (p} 3 - p 2) = 3.3 × 10 -3 ( 101 × 10 ³ -29 × 10 ³ ) = 237.6 [Pa · m ³ / s].

When the conductance C ′ of the leakage of the support arm 1 is calculated from the above C _A2 and C _of , 1 / C ′ = 1 / C _A2 + 1 / C _of = 1.6 × 10 ⁻² [m ³ / s].

[0039] and the leakage amount Q _l by the support arm 1, the conductance C 'leakage amount of the support arm 1, first / second suction ports 4a, the relationship between the pressure p ₃ in 4b, the first /
When the pressure p _x in the flow path in a state where one of the second suction ports 4a and 4b is open, Q _l =
C 'from the relationship _{(p 3 -p x), 237.6} = 1.6 × 10 -2 (101 × 10 3 -p x) ∴ p x = 101 × 10 3 - 237.6 / 1.6 × 10 -2 = 86 × 10 3 [Pa].

Therefore, the suction force P _VAC in a state where one of the first and second suction ports 4a and 4b of the support arm 1 is opened without being closed by the substrate W is P _VAC = p _{3 - p x = 101 × 10} 3 - 86 × 10 3 = 15 × 10 3 [Pa] = 0.153 a [kgf / cm ^2].

Therefore, if the opening area of the first / second suction ports 4a, 4b is 2.3 cm ² , the substrate W
Is 2.3 × 0.153 = 0.35 [kgf] ≒ 350 [gf].

That is, even if there is a suction leak, "350
gf ”of suction force can be obtained, and even if a notch or a defect is located at one of the suction ports, a substrate W of about 53 g and 8 inches in diameter can be sufficiently suctioned. Therefore, it is possible to prevent such a problem that the substrate W drops during the transfer.

In the above embodiment, the first suction port 4a and the second suction port 4a are provided on the substrate support surface 4 of the support arm 1.
Although two suction ports b were formed, the present invention is not limited to this number, and the number of suction ports is plural, and
It is only necessary that a suction passage communicating with each suction port is formed, and a throttle is formed at one portion of each suction passage.

The support portion 3 of the support arm 1 is not limited to the circular shape as described above, and the present invention can be applied to a tongue-shaped support portion.

<Second Embodiment> In the above-described first embodiment, a substrate transfer device in which a circular substrate W is suction-supported by the support arm 1 has been described as an example. In this embodiment, a liquid crystal display device or the like is used. An apparatus for sucking and supporting a rectangular substrate W at a plurality of locations by a support mechanism and transporting the same will be described as an example. FIG. 7 is a plan view showing a schematic configuration of the substrate transfer apparatus according to the embodiment, and FIG. 8 is a side view thereof.

The four corners of the upper surface of the rectangular substrate W are sucked and supported by the support mechanism 30, and the substrate W is turned and raised / lowered by the base 50 via the suspension mechanism 40 that suspends and supports the support mechanism 30. . In addition, the base 50 corresponds to the driving unit of the present invention.

A support mechanism 30 corresponding to the support means of the present invention
Is constituted by four support members 30a, and a suction portion 30b is provided at the lower end of each support member 30a. A suction port 30c is formed on the lower surface of each suction section 30b. Each suction port 30c communicates with a suction passage 30d formed in each support member 30a along the longitudinal direction.

The two support members 30a on the distal end side are connected to the first support arms 4 of the suspension mechanism 40 by the connecting portions 41, respectively.
2 near the tip. 2 on the base 50 side
The book support member 30a is attached to the vicinity of the distal end of the second support arm 44 by a projecting connecting portion 43 formed to project laterally, and is suspended and supported outside the second support arm 44. Thereby, each suction port 30c is connected to the substrate W
Are located at the four corners.

A horizontal suction passage 42a communicating with the suction passage 30d of the support member 30a is formed in the first support arm 42 and the second support arm 44. Each horizontal suction passage 42a is formed in the base 50. One suction path 50a
Is connected to the The suction passage 50a is connected to a vacuum pump via a suction hose (not shown).

[0050] Some position of each suction passage 30d leading to the suction port 30c as described above, the opening area is formed in each of the small aperture 30d _1, the resistance of the flow path of the suction passage 30d is large (or conductance Is smaller). The aperture area and the aperture length of the aperture 30d _1, as in the first embodiment described above, the suction port 30c, and the suction passage 30d, horizontal suction passage 42a
The suction path 50a, dimensions of a suction hose (not shown), the suction force of a vacuum pump, the size of the substrate W, and the like are set.

In the case of the substrate transfer apparatus configured as described above, for example, one of the four suction ports 30c may be separated from the upper surface of the substrate W due to vibration that may occur during the transfer.
Even if the upper surface of the substrate W cannot be suctioned due to a defect of the substrate W, etc., each of the suction passages 30d has a throttle 30d.
_{Since 1} is formed and the resistance of the flow path is increased, it is possible to suppress a suction leak in which a large amount of ambient air flows from the suction port 30c. As a result, the suction port 30c that sucks the upper surface of the substrate W can be prevented from being affected by the suction leak, and a decrease in the suction force can be suppressed.
Therefore, the substrate W can be securely held by suction irrespective of the posture of the substrate W, and it is possible to avoid a situation where the substrate W falls during transportation due to a decrease in the suction force.

In the first and second embodiments described above, the diaphragms 4a ₃ , 4b ₃ , and 30d ₁ are set to the first / second
The suction passages 4a ₂ , 4b ₂ and the suction passage 30d are formed by making the flow passages narrow. However, a member having a small opening area is arranged in the suction passage so that the flow passage resistance is increased (conductance is reduced). It may be.

[0053]

As is apparent from the above description, according to the first aspect of the present invention, the resistance is increased (or the conductance is reduced) at each throttle portion of the suction passage communicating with each of the plurality of suction ports. Therefore, suction leakage from the opened suction port can be suppressed. Therefore, it is possible to suppress the influence of the suction leak that the closed suction port receives from the opened suction port, and it is possible to suppress a decrease in the suction force. As a result, even when the substrate is supported in such a position that the cutout portion or the defective portion opens the suction port, a decrease in the suction force at the other suction ports can be suppressed, and the substrate is surely suction supported and transported. be able to.

According to the second aspect of the present invention, when the substrate is sucked and supported on the substrate support surface of the support arm, the notch portion or the missing portion is in a state where one of the suction ports is opened. Also, it is possible to suppress the influence of the suction leak received by the other suction ports. Therefore, even if the substrate is supported in such a position that the notch portion or the defective portion opens the suction port, a decrease in the suction force at the other suction ports can be suppressed, and the substrate is reliably suction-supported by the support arm. Can be transported.

According to the third aspect of the present invention, when the substrate is transported, only the peripheral portion of the lower surface of the substrate is sucked and supported, and the contact area can be reduced, so that contamination on the lower surface of the substrate is minimized. The arm can be a support arm that conveys only as much as possible. In particular, it can be suitable for transporting a circular substrate.

According to the fourth aspect of the present invention, when the substrate is sucked and supported at the end of the support member of the support means, the cutout portion or the cutout portion opens one of the suction ports. Even so, it is possible to suppress the influence of the suction leak received by the other suction ports. Therefore, even if the substrate is supported in such a position that the notched portion or the defective portion opens the suction port, a decrease in the suction force at the other suction ports can be suppressed, and the substrate is surely suction-supported by the support means. Can be transported. In particular, the present invention can be suitably applied to a rectangular substrate that conveys a plurality of locations while supporting it by suction.

Further, according to the fifth aspect of the present invention, the resistance (or conductance) of each suction passage can be made appropriate, so that all suction passages are properly closed in a closed state. The suction force can be exhibited, and even if some of the suction ports are opened, the other suction ports can generate a sufficient suction force.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating a schematic configuration of a substrate transfer device according to a first embodiment.

FIG. 2 is a side view of FIG.

FIG. 3 is a plan view of a support arm.

FIG. 4 is a side view of the support arm.

FIG. 5 is a view of FIG. 4 as viewed from below.

FIG. 6 is a sectional view taken along the line AA of FIG. 3;

FIG. 7 is a plan view illustrating a schematic configuration of a substrate transfer device according to a second embodiment.

FIG. 8 is a side view of FIG. 7;

FIG. 9 is a plan view showing a support arm of a conventional substrate transfer device.

[Explanation of symbols]

W ... substrate 1 ... supporting arm (supporting means) 2 ... proximal end 4 ... substrate supporting surface 4a ... first suction port 4b ... second suction ports 4a ₂ ... first suction passage 4b ₂ ... second suction passage 4a Reference numeral ₃ , 4b ₃ ··· diaphragm 11 ··· guide rail (drive means) 18 ··· electric motor (drive means) 20 ··· movable table 30 ··· support mechanism (support means) 30a ··· support member 30c ··· suction port 30d ··· suction path 30d ₁ ··· diaphragm 40 ... suspension mechanism 50 ... base (drive means)

Claims (5)

[Claims] 1. A substrate transfer apparatus, comprising: a support means for supporting a substrate; and a driving means for moving the support means, wherein the support means for supporting the substrate is moved by the drive means to transfer the substrate. The support means includes a plurality of suction ports formed to support the substrate by suction, and a suction passage communicating with the suction port and having a throttle formed in a part thereof. Substrate transfer device. 2. The substrate transfer apparatus according to claim 1, wherein said support means has a substrate support surface for supporting a substrate, and includes a support arm extending from a base end,
The substrate transfer device, wherein the suction port is formed in the substrate support surface. 3. The substrate transfer device according to claim 2, wherein the substrate support surface is formed in an arc shape with an open end, and is in contact with only a peripheral portion of a lower surface of the substrate. Substrate transfer device. 4. The substrate transfer device according to claim 1, wherein the support means includes a plurality of support members for supporting a plurality of end portions of the substrate, and the suction port is formed at a tip end of the support member. A substrate transfer device characterized by: 5. The substrate transfer apparatus according to claim 1, wherein a flow path cross-sectional area of said throttle is 0.5 to 1.
^{2. The} substrate transfer apparatus according to claim 1, wherein the length of the aperture is 3 to 8 mm.