JP6166143B2 - Transport system - Google Patents

Description

  The present invention relates to a transfer system, for example, a technology effective when applied to a wafer transfer system in a semiconductor manufacturing factory.

  In recent years, in semiconductor manufacturing factories, the so-called ballroom system, which cleans the entire factory, is being switched to a local cleaning system that cleans only the vicinity of semiconductor wafers (hereinafter abbreviated as wafers). .

  In semiconductor manufacturing plants that have introduced local cleaning technology, wafers are transferred from semiconductor manufacturing equipment to other semiconductor manufacturing equipment using a sealed cassette called FOUP (Front Opening Unified Pod) or SMIF (Standard Mechanical Interface). Transport. Further, each semiconductor manufacturing apparatus is provided with a local cleaning transfer chamber equipped with a cassette table called a load port. The local clean transfer chamber is a small clean room that plays a role of transferring wafers between the cassette and the semiconductor manufacturing apparatus.

  Wafers in the cassette placed on the load port are taken out one by one by the robot mechanism in the local cleaning transfer chamber and accommodated in the semiconductor manufacturing apparatus via the local cleaning transfer chamber. Further, the wafer that has been processed in the semiconductor manufacturing apparatus is accommodated in the cassette again via the local cleaning transfer chamber and transferred to the next step. In addition, about the local cleaning conveyance chamber, what was described, for example in patent document 1 is well-known.

JP 2004-165331 A

  Conventionally, cassettes have been moved between semiconductor manufacturing devices through human hands. Recently, however, a mechanism has been installed that runs on a track installed on the ceiling in a factory and raises and lowers the cassette by belt drive. In many cases, an unmanned transfer machine called OHT (Overhead Hoist Transfer) is used.

  In the case of a semiconductor manufacturing factory that has introduced a local cleaning technology, the OHT directly accesses the load port of the local cleaning transfer chamber to automatically transfer the cassette. However, for example, when the cassette is transported using both OHT and a human hand, it is necessary to manually place the cassette on the load port after the OHT is stopped to ensure safety.

  That is, if a cassette is manually placed on the load port by mistake during the operation of the OHT, a human hand or the cassette may come into contact with another cassette carried by the OHT, which is dangerous. In addition, when the cassettes come into contact with each other, the wafers accommodated in the cassettes may be damaged.

  As a countermeasure, for example, an optical sensor for monitoring is installed near the load port, and when the human hand or cassette approaches the load port and blocks the optical axis of the optical sensor during the operation of the OHT, the OHT is stopped. It is effective to provide such a safety mechanism.

  However, this measure makes it difficult to visually recognize the optical axis of the optical sensor, and it is also difficult to confirm at a glance whether the OHT is actually moving. There is a risk of blocking the optical axis of the sensor and stopping the OHT. Once the OHT is stopped, the cassette cannot be moved between the semiconductor manufacturing apparatuses, so that the operation rate of the factory is lowered, and as a result, the cost of the semiconductor product is increased.

  Also, as a safety mechanism with higher visibility than the optical sensor, it may be possible to shield the load port with a safety bar to ensure physical safety, but in this case, it takes time to remove the safety bar when releasing the safety. Also, the safety bar may accidentally come into contact with the cassette or the like during the work of removing the safety bar.

  An object of the present invention is to provide a transport system including a safety mechanism that prevents erroneous transport of a cassette in which a workpiece such as a wafer is accommodated.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

The conveyance system which is a preferable aspect of the present invention is:
A transfer chamber having a load port on which a cassette containing workpieces is placed;
A movable bar that moves up and down in conjunction with a plunger main body in a movable unit provided outside the transfer chamber;
A guide rail having a recess into which one end side of a plunger shaft inserted into the plunger body is inserted;
A stopper that comes into contact with the movable bar when one end side of the plunger shaft is inserted into the depression, and that comes into non-contact with the movable bar when one end side of the plunger shaft comes out of the depression;
When stopping the movable bar at a predetermined position, one end side of the plunger shaft is inserted into the depression by the urging force of the urging member inserted into the plunger shaft,
When the movable bar stopped at the predetermined position is moved up and down, the one end side of the plunger shaft is moved away from the depression by moving the movable bar in a direction against the urging force of the urging member. After the removal, the movable bar is moved up and down.

  The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

  It is possible to realize a transport system including a safety mechanism that can reliably prevent erroneous transport of a cassette in which a workpiece is accommodated.

(A) is a schematic front view of the local cleaning conveyance chamber which comprises a part of conveyance system of Embodiment 1, (b) is a schematic side view of this local cleaning conveyance chamber. It is a partially broken side view of a hoop. It is the schematic of OHT which conveys a hoop automatically. (A) is a schematic front view which shows the descending height of a movable safety bar, (b) is a schematic front view which shows the raising height of a movable safety bar. (A) is a partial front view of a movable unit, (b) is a schematic side view which shows the internal structure of a movable unit. It is the schematic which shows the internal structure of a plunger main body. (A) is a partial front view of a movable unit when a movable safety bar exists in a raise position, (b) is a schematic side view which shows the internal structure of a movable unit. It is a flowchart explaining the process of raising the movable safety bar stopped at the descending height and positioning it at the elevated height. (A)-(c) is a schematic side view of the movable unit in each process shown in FIG. It is a flowchart explaining the process of lowering and positioning the movable safety bar stopped at the raised height to the lowered height. (A)-(c) is a schematic side view of the movable unit in each process shown in FIG. (A) is a schematic side view which shows the internal structure of the movable unit which comprises a part of conveyance system of Embodiment 2, (b) is the upper part along the AA line of (a). It is the schematic plan view seen from. (A) is a schematic side view explaining the process of raising the movable safety bar stopped at the descending height, and (b) is a view of the part along the line BB of (a) from above. FIG. (A) is a schematic side view of a movable unit when a movable safety bar exists in a raise position, (b) is the schematic top view which looked at a part of (a) from upper direction. (A) is a schematic side view explaining the process of lowering the movable safety bar stopped at the rising height, and (b) is a schematic plan view of a part of (a) as viewed from above. .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof will be omitted. In the embodiments, the description of the same or similar parts will not be repeated in principle unless particularly necessary.

(Embodiment 1)
Fig.1 (a) is a schematic front view of the local cleaning conveyance chamber which comprises some conveyance systems of this Embodiment 1, The figure (b) is a schematic side view of this local cleaning conveyance chamber. It is. FIG. 2 is a partially broken side view of the hoop. FIG. 3 is a schematic view of an OHT that automatically conveys a hoop.

  The first embodiment is applied to a wafer transfer system in a semiconductor manufacturing factory. As shown in FIG. 1, a local cleaning transfer chamber 10 that constitutes a part of a wafer transfer system is installed adjacent to a semiconductor manufacturing apparatus 11, and the inside thereof is a fan that generates a downflow of clean air. A clean atmosphere is maintained by the filter unit 12.

  A load port 15 on which the hoop 14 is placed is installed on the front-side outer wall of the local cleaning transfer chamber 10. The hoop 14 is a kind of sealed cassette for carrying wafers. As shown in FIG. 2, a plurality of silicon wafers (workpieces) 18 having a diameter of 300 mm are accommodated therein at a predetermined interval. As shown in FIG. 3, the hoop 14 travels on a track rail 16 installed on a ceiling in a semiconductor manufacturing factory, and is automatically transported by an OHT (automatic transport mechanism) 17 that moves up and down by a belt drive, and is loaded on the load port 15. Placed. Further, the hoop 14 may be manually conveyed by an operator in the semiconductor manufacturing factory and manually placed on the load port 15.

  The silicon wafers 18 in the FOUP 14 placed on the load port 15 by the OHT 17 or manually are taken out one by one from the FOUP 14 by the robot mechanism 19 in the local cleaning transfer chamber 10 shown in FIG. It is accommodated in the manufacturing apparatus 11 and subjected to a predetermined process. Further, the silicon wafer 18 that has been processed is taken out of the semiconductor manufacturing apparatus 11 by the robot mechanism 19 and then accommodated in the FOUP 14 on the load port 15 again, and is transferred to the next step by the OHT 17 or manually.

  Specifically, the semiconductor manufacturing apparatus 11 is formed on a silicon wafer 18 such as a CVD apparatus, a dry etching apparatus, a cleaning apparatus, a sputtering apparatus, an exposure apparatus, or the like for forming an integrated circuit on the silicon wafer 18. An inspection apparatus for evaluating the characteristics of an integrated circuit. That is, in the semiconductor manufacturing factory, a plurality of sets of semiconductor processing apparatuses including the local cleaning transfer chamber 10 having the load port 15 and the semiconductor manufacturing apparatus 11 as a set are arranged in parallel. Then, an integrated circuit is formed on the silicon wafer 18 by sequentially transporting the hoop 14 containing the silicon wafer 18 to the plurality of sets of semiconductor processing apparatuses.

  As shown in FIG. 1, shielding plates 20 for supporting and fixing the fixed safety bar 21 and the movable unit 22 are attached to both sides of the front surface of the local cleaning transfer chamber 10. The shielding plate 20 is made of a metal plate such as aluminum or stainless steel.

  The fixed safety bar 21 is made of a metal plate such as aluminum or stainless steel, and has one end fixed to one shielding plate 20 and the other end fixed to the other shielding plate 20. The fixed safety bar 21 is disposed at a position higher than the hoop 14 placed on the load port 15, and the position is unchanged.

  The movable unit 22 is fixed to each of the two shielding plates 20 and is disposed at a position lower than the fixed safety bar 21. A movable safety bar 23 is attached to the pair of movable units 22 so as to be movable up and down. One end of the movable safety bar 23 is supported by one movable unit 22, and the other end is supported by the other movable unit 22. The movable safety bar 23 is made of a metal plate such as aluminum or stainless steel like the fixed safety bar 21, and its shape and dimensions are substantially the same as those of the fixed safety bar 21. A part of the movable safety bar 23 is provided with a pair of handles 24 used when an operator manually raises and lowers the movable safety bar 23.

  The movable range of the movable safety bar 23 in the vertical direction is between the descending height (H1) shown in FIG. 4 (a) and the ascending height (H2) shown in FIG. 4 (b). As shown in FIG. 4A, when the movable safety bar 23 is at the lowered height (H1), the hoop 14 placed on the load port 15 is blocked by the movable safety bar 23. Touching the hoop 14 by mistake can be prevented. In addition, when the hoop 14 is not placed on the load port 15 and the movable safety bar 23 is at the lowered height (H1), an operator mistakenly places the hoop 14 on the load port 15 during the operation of the OHT 17. Can be prevented.

  FIG. 5A is a partial front view of the movable unit 22, and FIG. 5B is a schematic side view showing the internal structure of the movable unit 22.

  Inside the movable unit 22, a slider 31 that moves up and down in the movable unit 22 along the linear guide 30 and a plunger main body 32 that is fixed to the slider 31 and moves up and down together with the slider 31 are attached. The plunger body 32 is inserted with a plunger shaft 33 that moves in the left-right direction in FIG.

  A roller bearing 34 is fixed to one end of the plunger shaft 33. Further, the other end of the plunger shaft 33 is exposed to the outside of the movable unit 22, and the movable safety bar 23 is fixed to the exposed portion. Therefore, when the operator grasps the handle 24 and pulls the movable safety bar 23 in the left direction of FIG. 5B, that is, toward the front as viewed from the operator, the plunger shaft 33 and the roller bearing 34 are moved to the movable safety bar 23. Move together in the same direction.

  As shown in FIG. 6, a coiled compression spring (first urging member) 35 is contained in the plunger main body 32. Therefore, the movable safety bar 23, the plunger shaft 33, and the roller bearing 34 are always urged in the right direction in FIG. Accordingly, when the operator grasps the handle 24 and pulls the movable safety bar 23 forward (leftward in the figure) and then releases the handle 24, the movable safety bar 23, the plunger shaft 33 and the roller bearing 34 are released. Is moved rightward by the urging force of the compression spring 35. The urging member is not limited to the compression spring 35 inserted into the plunger main body 32. That is, any biasing member can be used as long as it can elastically bias the movable safety bar 23, the plunger shaft 33, and the roller bearing 34 in the right direction in FIG.

  Further, as shown in FIG. 5B, one end of a wire 37 wound around a mainspring unit 36 installed at the uppermost part of the movable unit 22 is connected to the plunger main body 32. Therefore, the plunger main body 32 and the movable safety bar 23, the plunger shaft 33 and the roller bearing 34 interlocked with the plunger main body 32 are always urged upward by the wire 37 wound around the mainspring unit 36. Therefore, the operator can raise the movable safety bar 23 with a light force. In addition, when the operator lowers the movable safety bar 23, the movable safety bar 23 does not fall suddenly even if the operator carelessly removes the hand from the handle 24. The member that urges the plunger main body 32 upward is not limited to the wire 37 wound around the mainspring unit 36.

  As shown in FIG. 5 (b), a guide rail 39 provided with a pair of recesses (lower recess 38a, upper recess 38b) for regulating the position of the movable safety bar 23 is attached to the inner wall of the movable unit 22. It has been. The lower depression 38a corresponds to the lowered height (H1) of the movable safety bar 23 shown in FIG. 4, and the upper depression 38b corresponds to the raised height (H2).

  Further, on the outer wall of the movable unit 22, a lower stopper 40a for stopping the movable safety bar 23 at the lowered height (H1) and an upper stopper 40b for stopping the movable safety bar 23 at the raised height (H2). And are attached. As shown in FIG. 5A, the lower stopper 40 a and the upper stopper 40 b are attached at positions that do not interfere with the movement of the plunger shaft 33 that moves up and down along the linear motion guide 30.

  As shown in FIG. 5B, the lower stopper 40a comes into contact with the movable safety bar 23 when the roller bearing 34 fixed to one end of the plunger shaft 33 is inserted into the lower recess 38a. Yes. At this time, the movable safety bar 23 cannot move above the descending height (H1). In order to raise the movable safety bar 23, the operator pulls the movable safety bar 23 forward (to the left in the figure) to remove the roller bearing 34 from the lower recess 38a, and removes the movable safety bar 23 and the lower stopper 40a. Need to be contactless.

  As shown in FIGS. 7A and 7B, the upper stopper 40b comes into contact with the movable safety bar 23 when the roller bearing 34 is inserted into the upper recess 38b. At this time, the movable safety bar 23 cannot move below the rising height (H2). In order for the operator to lower the movable safety bar 23, it is necessary to pull the movable safety bar 23 forward to remove the roller bearing 34 from the upper recess 38b so that the movable safety bar 23 and the upper stopper 40b are not in contact with each other. .

  As shown in FIG. 5B, a movable proximity sensor 42 is attached to the plunger shaft 33 via a sensor plate 41. That is, the movable proximity sensor 42 moves in conjunction with the movable safety bar 23 fixed to the plunger shaft 33. On the other hand, a fixed proximity sensor 43 is attached to the lower end of the guide rail 39. The fixed proximity sensor 43 is arranged to have the same height as the movable proximity sensor 42 when the movable safety bar 23 is at the lowered height (H1).

  The movable proximity sensor 42 is closest to the fixed proximity sensor 43 when the roller bearing 34 is inserted into the lower recess 38a, and transmits an ON signal to the OHT 17. The movable proximity sensor 42 transmits an OFF signal to the OHT 17 when the roller bearing 34 is disengaged from the lower depression 38a and the distance from the fixed proximity sensor 43 increases. The OHT 17 senses these signals and determines whether the hoop 14 can be moved or stopped.

  Next, the positioning process of the movable safety bar 23 will be described in detail. FIG. 8 is a flowchart for explaining a process of raising the movable safety bar 23 stopped at the lowered height (H1) and positioning it at the raised height (H2). 9A to 9C are schematic side views of the movable unit 22 in each step shown in FIG.

  First, as shown in FIG. 9A, the handle 24 of the movable safety bar 23 stopped at the descending height (H1) is pulled forward (S01a), and the roller bearing 34 is moved from the lower recess 38a of the guide rail 39. Remove (S01b). Thereby, since the movable safety bar 23 and the lower stopper 40a are not in contact with each other, the movable safety bar 23 can be raised. At this time, the distance between the movable proximity sensor 42 and the fixed proximity sensor 43 is increased (S01c), and as a result of the movable proximity sensor 42 transmitting an OFF signal to the OHT 17, the OHT 17 stops (S01d).

  Next, as shown in FIG. 9B, the handle 24 of the movable safety bar 23 is pulled up (S02a). As a result, the roller bearing 34 rises while being pressed against the surface of the guide rail 39 by the urging force of the compression spring 35, so that the movable safety bar 23 rises smoothly without contacting the lower stopper 40a and the upper stopper 40b. (S02b).

  As shown in FIG. 9C, when the movable safety bar 23 is further raised and the roller bearing 34 reaches the position of the upper recess 38b, the roller bearing 34 is moved upward by the biasing force of the compression spring 35 (see FIG. 6). It is inserted into the recess 38b (S03a). As a result, the lower surface of the movable safety bar 23 comes into contact with the upper surface of the upper stopper 40b, so that the movable safety bar 23 is positioned at the raised height (H2) (S03b).

  When the handle 24 of the movable safety bar 23 is pulled up with an unnecessarily strong force, the roller bearing 34 exceeds the height of the upper recess 38b, and the movable safety bar 23 moves above the raised height (H2). There is. In this case, since the movable safety bar 23 comes into contact with the above-described fixed safety bar 21 (see FIG. 1) and stops, the movable safety bar 23 may be lowered to the raised height (H2).

  FIG. 10 is a flowchart illustrating a process of lowering the movable safety bar 23 stopped at the rising height (H2) and positioning it at the lowering height (H1). FIGS. 11A to 11C are schematic side views of the movable unit 22 in each step shown in FIG.

  First, as shown in FIG. 11A, the handle 24 of the movable safety bar 23 stopped at the rising height (H2) is pulled forward (S04a), and the roller bearing 34 is removed from the upper recess 38b of the guide rail 39. Remove (S04b). Thereby, since the movable safety bar 23 and the upper stopper 40a are not in contact with each other, the movable safety bar 23 can be lowered.

  Next, as shown in FIG. 11B, the handle 24 of the movable safety bar 23 is pulled down (S05a). As a result, the roller bearing 34 is lowered while being pressed against the surface of the guide rail 39 by the urging force of the compression spring 35, so that the movable safety bar 23 is smoothly lowered without contacting the upper stopper 40b and the lower stopper 40a. (S05b).

  As shown in FIG. 11C, when the movable safety bar 23 is further lowered and the roller bearing 34 reaches the position of the lower depression 38a, the roller bearing 34 is inserted into the lower depression 38a by the biasing force of the compression spring 35. (S06a). Thereby, since the upper surface of the movable safety bar 23 contacts the lower surface of the lower stopper 40a, the movable safety bar 23 is positioned at the lowered height (H1) (S06b). At this time, the distance between the movable proximity sensor 42 and the fixed proximity sensor 43 approaches (S06c), and the movable proximity sensor 42 transmits an ON signal. As a result, the stopped state of the OHT 17 is released (S06d).

  Thus, according to the wafer conveyance system of the first embodiment, the hoop 14 placed on the load port 15 is blocked by the movable safety bar 23 with high visibility, so that the operator mistakenly loads the load port 15. It is possible to reliably prevent erroneous conveyance in which the upper hoop 14 is touched or an operator mistakenly places the hoop 14 on the load port 15 during the operation of the OHT 17.

  When the movable safety bar 23 is positioned at the lowered height (H1) or the raised height (H2), the roller bearing 34 is moved to the lower depression 38a (or the upper depression 38b) of the rail guide 39 by the urging force of the compression spring 35. Therefore, the positioning operation of the movable safety bar 23 can be easily performed.

  Further, when the movable safety bar 23 is moved up and down, it is necessary to pull the movable safety bar 23 forward in advance to remove the roller bearing 34 from the lower recess 38a (or the upper recess 38b) of the rail guide 39. Can be reliably prevented.

(Embodiment 2)
FIG. 12A is a schematic side view showing the internal structure of the movable unit 22 constituting a part of the transport system of the second embodiment, and FIG. 12B is a part of FIG. It is the schematic plan view which looked at (the part along the AA line) from upper direction.

  The transfer system of the second embodiment and the transfer system of the first embodiment are different in the structure of the movable unit 22 fixed to the shielding plate 20 of the local clean transfer chamber 10. That is, in the movable unit 22 of the first embodiment, the operator pulls the handle 24 of the movable safety bar 23 toward the front so that the roller bearing 34 is removed from the recesses (the lower recess 38a and the upper recess 38b) of the guide rail 39. It has a structure. On the other hand, in the movable unit 22 according to the second embodiment, the operator pushes the handle 24 in the back (opposite direction) so that the roller bearing 34 is depressed in the guide rail 39 (lower depression 38a, upper depression). 38b).

  As shown in FIG. 12A, inside the movable unit 22, a slider 31 that moves up and down in the movable unit 22 along the linear guide 30, and a plunger main body that is fixed to the slider 31 and moves up and down together with the slider 31. 32 is attached. Further, a plunger shaft 33 that moves in the left-right direction in FIG.

  A roller bearing 34 and one end of a joint 44 are fixed to the plunger shaft 33. The other end of the joint 44 is exposed to the outside of the movable unit 22, and the movable safety bar 23 is fixed to the exposed portion. Accordingly, the plunger shaft 33, the joint 44, and the roller bearing 34 move in the left-right direction in FIG. 12A in conjunction with the movable safety bar 23.

  Although not shown, the plunger main body 32 contains an urging member such as a push spring. Therefore, the plunger shaft 33, the joint 44, the roller bearing 34, and the movable safety bar 23 are always urged in the left direction in FIG. Therefore, when the operator grasps the handle 24 and pushes the movable safety bar 23 to the back (right direction in the figure) and then releases the handle 24, the movable safety bar 23, the plunger shaft 33, the joint 44, and the roller are removed. The bearing 34 moves to the left by the urging force of the push spring.

  One end of a wire 37 extending from a mainspring unit 36 installed at the top of the movable unit 22 is connected to the plunger main body 32. Therefore, the plunger main body 32 and the movable safety bar 23, the joint 44, the plunger shaft 33, and the roller bearing 34 that are interlocked with the plunger main body 32 are always pulled upward. Therefore, the operator can raise the movable safety bar 23 with a light force. In addition, when the operator lowers the movable safety bar 23, the movable safety bar 23 does not fall suddenly even if the operator carelessly removes the hand from the handle 24.

  A guide rail 39 provided with a pair of depressions (lower depression 38a and upper depression 38b) for restricting the position of the movable safety bar 23 is attached to the inner wall of the movable unit 22. The lower depression 38a corresponds to the lowered height (H1) of the movable safety bar 23, and the upper depression 38b corresponds to the raised height (H2). That is, as shown in FIG. 12A, when the roller bearing 34 fixed to the plunger shaft 33 interlocked with the movable safety bar 23 is inserted into the lower recess 38a, the movable safety bar 23 is lowered to the lowering height (H1). ) On the other hand, although illustration is omitted, when the roller bearing 34 is inserted into the upper recess 38b, the movable safety bar 23 reaches the raised height (H2).

  On the outer wall of the movable unit 22, there are a lower stopper 40a for stopping the movable safety bar 23 at the lowered height (H1), and an upper stopper 40b for stopping the movable safety bar 23 at the raised height (H2). It is attached. As shown in FIG. 12B, a part of the lower surface of the lower stopper 40a comes into contact with the upper surface of the movable safety bar 23 when the roller bearing 34 fixed to the plunger shaft 33 is inserted into the lower recess 38a. It is supposed to be. At this time, the operator cannot move the movable safety bar 23 above the descending height (H1).

  A movable proximity sensor 42 is attached to the plunger shaft 33 via a sensor plate 41. That is, the movable proximity sensor 42 moves in conjunction with the movable safety bar 23 fixed to the plunger shaft 33. On the other hand, a fixed proximity sensor 43 is attached to the lower end of the guide rail 39. The fixed proximity sensor 43 is arranged to have the same height as the movable proximity sensor 42 when the movable safety bar 23 is at the lowered height (H1).

  The movable proximity sensor 42 is closest to the fixed proximity sensor 43 when the roller bearing 34 is inserted into the lower recess 38a, and transmits an ON signal to the OHT 17. The movable proximity sensor 42 transmits an OFF signal to the OHT 17 when the roller bearing 34 is disengaged from the lower depression 38a and the distance from the fixed proximity sensor 43 increases.

  As shown in FIGS. 13A and 13B, when the operator pushes the movable safety bar 23 stopped at the descending height (H1) in the back (right direction in the figure), the roller bearing 34 is lowered. Since the movable safety bar 23 and the lower stopper 40a are not in contact with each other, the movable safety bar 23 can be moved above the descending height (H1). Further, when the movable safety bar 23 is pushed inward, the distance between the movable proximity sensor 42 and the fixed proximity sensor 43 increases, and the movable proximity sensor 42 transmits an OFF signal to the OHT 17, thereby stopping the OHT 17.

  As shown in FIGS. 14A and 14B, when the movable safety bar 23 is stopped at the rising height (H2), a part of the upper surface of the upper stopper 40b is in contact with the lower surface of the movable safety bar 23. It is supposed to be. At this time, the operator cannot move the movable safety bar 23 below the raised height (H2).

  As shown in FIGS. 15 (a) and 15 (b), when the operator pushes the movable safety bar 23 stopped at the rising height (H2) in the back (right direction in the figure), the roller bearing 34 is moved upward. Since the movable safety bar 23 and the upper stopper 40b come out of contact with each other, the movable safety bar 23 can be moved below the raised height (H2).

  Next, when the handle 24 of the movable safety bar 23 is pulled down, the roller bearing 34 descends while being pressed against the surface of the guide rail 39 by the urging force of the push spring, so that the movable safety bar 23 has the upper stopper 40b and the lower stopper 40a. It descends smoothly without touching.

  When the movable safety bar 23 is further lowered and the roller bearing 34 reaches the position of the lower recess 38a of the guide rail 39, the roller bearing 34 is inserted into the lower recess 38a by the biasing force of the push spring. Thereby, since the upper surface of the movable safety bar 23 contacts the upper surface of the lower stopper 40a, the movable safety bar 23 is positioned at the lowered height (H1) (see FIG. 12). At this time, the distance between the movable proximity sensor 42 and the fixed proximity sensor 43 approaches and the movable proximity sensor 42 transmits an ON signal. As a result, the stop state of the OHT 17 is released.

  Thus, according to the wafer transfer system of the second embodiment, the same effects as those of the wafer transfer system of the first embodiment can be obtained.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  In the above-described embodiment, an example in which the present invention is applied to a wafer transfer system in a semiconductor manufacturing factory has been described. However, the present invention is not limited to this example. You can also.

  The present invention can be used for a wafer transfer system in a semiconductor manufacturing factory.

DESCRIPTION OF SYMBOLS 10 Local cleaning conveyance chamber 11 Semiconductor manufacturing apparatus 12 Fan filter unit 14 Hoop (cassette)
15 Load port 16 Track rail 17 OHT (automatic transfer mechanism)
18 Wafer (work)
19 robot mechanism 20 shielding plate 21 fixed safety bar 22 movable unit 23 movable safety bar 24 handle 30 linear motion guide 31 slider 32 plunger main body 33 plunger shaft 34 roller bearing 35 compression spring (first biasing member)
36 Spring unit 37 Wire 38a Lower depression 38b Upper depression 39 Guide rail 40a Lower stopper 40b Upper stopper 41 Sensor plate 42 Movable proximity sensor 43 Fixed proximity sensor 44 Joint

Claims (10)

A transfer chamber having a load port on which a cassette containing workpieces is placed;
An automatic transfer mechanism installed outside the transfer chamber and automatically placing the cassette on the load port;
A plunger main body, a first biasing member accommodated in the plunger main body, a plunger shaft inserted into the plunger main body, and a guide rail including a recess into which one end side of the plunger shaft is inserted. A movable unit with built-in,
A movable bar installed outside the movable unit and moving up and down in conjunction with the plunger body;
The movable unit is installed outside the movable unit, and comes into contact with the movable bar when one end side of the plunger shaft is inserted into the depression, and when the one end side of the plunger shaft comes out of the depression, the movable bar and A non-contact stopper,
Have
When stopping the movable bar at a predetermined position, the one end side of the plunger shaft is inserted into the depression by the biasing force of the first biasing member,
When the movable bar stopped at the predetermined position is moved up and down, the movable bar is moved in a direction against the urging force of the first urging member, whereby one end side of the plunger shaft is moved to the end. A transport system that moves the movable bar up and down after removing it from the recess. The transport system according to claim 1,
The transfer system includes a robot mechanism that includes a robot mechanism that takes out the workpiece from the cassette placed on the load port and transfers the workpiece to a predetermined location. The transport system according to claim 1,
The conveying system in which the plunger main body is urged upward by a second urging member. The transport system according to claim 1,
The movable unit operates the automatic conveyance mechanism when one end side of the plunger shaft is inserted into the depression, and operates the automatic conveyance mechanism when one end side of the plunger shaft comes out of the depression. Transport system with a sensor to stop. The transport system according to claim 4, wherein
The sensor includes a movable sensor that moves in conjunction with the movable bar, and a fixed sensor that is disposed in proximity to the movable sensor when one end side of the plunger shaft is inserted into the recess. system. The transport system according to claim 1,
The transfer system, wherein the workpiece is a semiconductor wafer, and the transfer chamber is a local cleaning transfer chamber installed adjacent to a semiconductor manufacturing apparatus. The transport system according to claim 1,
The conveyance system, wherein the first biasing member is a compression spring. The transport system according to claim 1,
The transport system, wherein the first biasing member is a push spring. In the conveyance system of Claim 3,
The second urging member includes a mainspring unit installed on an upper part of the movable unit, and a wire wound around the mainspring unit and having one end connected to the plunger main body. The transport system according to claim 1,
One end side of the plunger shaft is inserted into the recess when the movable bar is stopped at the predetermined position, and is in contact with the surface of the guide rail when the movable bar is moving up and down. Conveying system with roller bearings that move up and down.

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