JP5928185B2 - Board transfer equipment - Google Patents

Description

  The present invention relates to a substrate transport facility for transporting a substrate.

  As a device for performing heat treatment on a substrate such as a semiconductor wafer (hereinafter referred to as “wafer”), a large number of wafers loaded on a wafer boat as a substrate holder are collectively processed in a reaction tube. A vertical heat treatment apparatus is known. In this apparatus, for example, five wafers are sequentially taken out from a FOUP (Front-Opening Unified Pod), which is a wafer storage container (substrate storage unit), by a wafer transfer arm (holding unit) and transferred to a wafer boat. The empty FOUP is transported to the storage unit, and the wafer is similarly transferred from another FOUP. Thus, for example, after about 100 wafers are stacked on the wafer boat, the wafer boat is raised and inserted into the reaction tube, and the heat treatment described above is performed. Therefore, in the loading area (substrate transfer area) where the wafer is transferred, a ball screw extending in the vertical direction is arranged as an elevating mechanism in order to raise and lower the wafer transfer arm in accordance with the loading position of each wafer on the wafer boat. ing.

  The substrate transfer region and the holding device standby region where the wafer boat is placed are arranged in the lateral direction in order to suppress scattering of particles generated by driving the arm, and to cool the high-temperature wafer boat and wafer after heat treatment. The airflow toward is formed so as to extend in the vertical direction and in the horizontal direction. Specifically, for example, a filter unit that blows clean gas toward the respective regions and an exhaust duct for exhausting the clean gas are arranged on the left and right sides so as to face each other through the regions. . And below the floor surface of these regions, in order to circulate the gas flowing into the exhaust duct while cooling from the exhaust duct to the filter unit, a circulation passage provided with a heat exchanger, A fan for forming an airflow is accommodated. In order to prevent the particles from rolling up, the fan has an air volume that allows the clean gas to flow in a laminar flow of extremely fine air (for example, about 0.5 m / s).

  When the wafer transfer arm is moved up and down, the ball screw rotates around the vertical axis. However, since the ball screw is coated with lubricating oil (oil) such as organic matter, particles derived from the oil may be scattered by centrifugal force. On the other hand, in order to improve the throughput, it is required to shorten the time required for wafer transfer by the wafer transfer arm. For this reason, it is desired to increase the speed of the lifting / lowering operation of the wafer transfer arm, but in that case, there is a concern that the generation of particles and the risk of contamination by organic substances are further increased.

  In suppressing the scattering of particles from such a ball screw, when the air volume of the fan described above is increased, turbulent flow occurs in the transport area and the holder waiting area, and the particles rise. Further, if a physical cover for preventing the scattering of particles is simply provided around the ball screw, there is a possibility that particles may wrap around the cover and reach the substrate transport area. On the other hand, when an exhaust unit that exhausts locally is provided as in Patent Document 1, for example, the apparatus becomes larger by the amount of the exhaust unit, and a laminar flow is difficult to form, resulting in a decrease in throughput ( Resulting in a decrease in the temperature drop rate of the wafer).

JP 2005-347667 A

  The present invention has been made in view of such circumstances, and its purpose is to prevent contamination of the substrate by particles generated in an elevating mechanism for raising and lowering the holding unit when the substrate is held and transported by the holding unit. It is to provide a technology that can be suppressed.

The substrate transfer facility of the present invention includes an elevating base, an elevating mechanism for elevating the elevating base, and a holding unit for holding and transporting the substrate, and the elevating base is on one side of the left and right when viewed from the elevating mechanism. A substrate transport mechanism configured to extend and further bend and extend forward, the tip being provided with the holding portion ;
Between the substrate transport area where the substrate is transported by the holding unit and the lifting mechanism, the lifting mechanism is located along the lifting area with the lifting area of the lifting base in front of the lifting mechanism. An exhaust duct provided independently of the base body ,
The exhaust duct is characterized in that a gas suction port for sucking particles generated from the lifting mechanism is formed so as to face the lifting mechanism side and along the lifting region .

The lifting mechanism may be a ball screw mechanism.
A circulation path through which gas sucked from the exhaust duct passes;
A gas supply unit configured to supply the gas returned through the circulation path to the substrate transfer region and form a layered air flow toward the exhaust duct via the substrate transfer region. .
In the substrate transfer area, a substrate holder for holding the substrate in a shelf shape and carrying it in and out of a vertical reaction tube for performing heat treatment on the substrate is disposed,
The substrate transport mechanism may be for transporting a substrate to and from the substrate holder.
The said exhaust duct may be provided between the position of the board | substrate on the said holding part when the said holding part raises / lowers via the said raising / lowering mechanism, and the said raising / lowering mechanism.

At least one of the left and right side surfaces when the holding unit side is viewed from the lifting mechanism is such that a gas suction port for sucking particles generated from the lifting mechanism faces the lifting mechanism side. An auxiliary exhaust duct formed along the length direction of the lifting mechanism may be disposed, and in this case, the gas suction ports are formed on both left and right sides when the holding unit side is viewed from the lifting mechanism. May have been.
The exhaust duct and the auxiliary duct may be shared so that the internal areas of the exhaust duct and the auxiliary duct communicate with each other.

  The present invention provides a gas suction port for sucking particles between the lifting mechanism for lifting and lowering the holding unit for holding the substrate and the substrate transfer area, and the length of the lifting mechanism. Exhaust ducts formed along the direction are arranged. Therefore, the scattering of the particles to the substrate transport area side can be suppressed, so that the contamination of the substrate by the particles can be suppressed.

It is a longitudinal cross-sectional view which shows roughly an example of the vertical heat processing apparatus of this invention. It is a cross-sectional top view which shows the said vertical heat processing apparatus. It is a perspective view which shows the arm used for the said vertical heat processing apparatus. It is a perspective view which shows the ball screw for the said arm to raise / lower. It is a perspective view which shows typically the airflow formed in the said vertical heat processing apparatus. It is a longitudinal cross-sectional view which shows the said airflow. It is a cross-sectional plan view which expands and shows the area | region where the said ball screw is arrange | positioned. It is a perspective view which shows the airflow which goes to the said ball screw. It is a cross-sectional top view which shows typically the effect | action of the said vertical heat processing apparatus. It is a cross-sectional top view which shows typically the effect | action of the said vertical heat processing apparatus. It is a perspective view which shows the other example of the said vertical heat processing apparatus. It is a cross-sectional top view which shows the vertical heat processing apparatus of the said other example. It is a perspective view which shows another example of the said vertical heat processing apparatus. It is a cross-sectional top view which shows the said another vertical heat processing apparatus. It is a perspective view which shows the other example of the said vertical heat processing apparatus. It is a cross-sectional top view which shows the vertical heat processing apparatus of the said further another example. It is a cross-sectional top view which shows another example of the said vertical heat processing apparatus.

  An example of an embodiment according to the substrate transfer facility of the present invention will be described with reference to FIGS. First, the outline of a vertical heat treatment apparatus to which the substrate transfer equipment is applied will be briefly described. As shown in FIG. 1, this apparatus includes a wafer boat 1 for loading a plurality of wafers W in a shelf shape, and the wafer. And a vertical reaction tube 2 for hermetically storing the boat 1 and performing heat treatment. Further, a wafer transfer arm 3 for transferring the wafer W to the wafer boat 1 is provided as a substrate transfer mechanism, and a substrate transfer area 10a where the wafer W is transferred by the arm 3 and the lower side of the reaction tube 2 In FIG. 2, an air flow by clean gas is formed with respect to the holder standby region 10b in which the wafer boat 1 waits. And even if the arm 3 performs the raising / lowering operation, a member (described later) that forms the air current so that the particles are not scattered from the ball screw 4 that is the raising / lowering mechanism for raising and lowering the arm 3 or the scattering is suppressed. The shape and layout of the local exhaust duct 50) are adjusted. Actually, the arm 3 is arranged on the front side of the apparatus with respect to the wafer boat 1, but in the following description, for convenience of illustration, the arrangement of the wafer boat 1 and the arm 3 is referred to as “front-rear direction (wafer boat 1 is the front side and the arm 3 is the back side), and a direction that is horizontally orthogonal to the front-back direction when the arm 3 is viewed from the wafer boat 1 is referred to as a “left-right direction”.

  First, the overall configuration of this apparatus will be briefly described. The above-described reaction tube 2 is arranged above the holder standby region 10b for transferring the wafer W to the wafer boat 1. The substrate transfer area 10a is adjacent to the rear side (X direction in FIG. 1) of the holder standby area 10b. A work area 12 for transporting and storing the FOUP 11 is provided on the back side of the substrate transport area 10a. That is, in the work area 12, the placement unit 21 on which the FOUP 11 is placed by a transport mechanism (not shown) outside the apparatus and the FOUP 11 placed on the placement unit 21 are described in the work area 12 as described above. A carrier transporter 23 that is transferred to a transfer stage 22 adjacent to the arm 3 is provided. Then, the FOUP 11 that has been emptied after being taken out of the wafer W is stored in the storage unit 24 above the mounting unit 21, and the processed wafer W is returned to the original FOUP 11 and unloaded from the apparatus. It is configured to be. In this example, the transfer stage 22 is provided at two locations so as to be separated from each other in the vertical direction.

  In FIG. 1, reference numeral 25 denotes a casing that forms the outer wall of the apparatus, and reference numeral 26 denotes a door provided on the casing 25. A wall surface portion between the work area 12 and the substrate transfer area 10a forms a part of the housing 25, and partitions between the work area 12 and the substrate transfer area 10a and is provided on the wall surface portion. The shutter 27 is configured to open and close a transfer port (opening) 28 for transferring the wafer W. Above the holder waiting area 10b, a heater for heating the wafer W in the reaction tube 2 to, for example, 600 ° C., an opening / closing mechanism for opening and closing the furnace port at the lower end opening of the reaction tube 2, and Is provided with a gas supply system or the like for supplying a processing gas (film formation gas) into the reaction tube 2, but is drawn in a simplified manner in FIG. 1. Further, drawing of the work area 12 is omitted except for FIG.

  Next, the layout of each part in the substrate transfer area 10a and the holder waiting area 10b will be described in detail. In these regions 10a and 10b, as described above, the arm 3 and the wafer boat 1 which are substrate transfer mechanisms are arranged in this order from the back side toward the front side. In a region that is dislocated to one side (left side in FIG. 2) with respect to the arm 3 when viewed in a plan view, the length of the wafer boat 1 is used to raise and lower the arm 3 as shown in FIGS. A ball screw 4 that is an elevating mechanism extending in the vertical direction along the direction is disposed. The ball screw 4 is configured to be rotatable around the vertical axis at a rotational speed of, for example, 900 rpm to 1300 rpm, for example, by a drive unit 4 a provided on the lower side of the floor 5 of the apparatus, and horizontally toward the arm 3. It arrange | positions so that the one end side of the support part 3a which is a plate-shaped raising / lowering base | substrate extended may be penetrated. Note that FIG. 1 described above is drawn by shifting the ball screw 4 to the side (the shutter 27 side) so that the ball screw 4 can be seen. In addition, for example, a bearing portion (not shown) is provided at the upper end portion of the ball screw 4 in order to support the ball screw 4 so as to be rotatable around the vertical axis.

  The other end side of the support portion 3a is provided with a gas suction port 53 for taking in gas in the local exhaust duct 50 on the front side of the ball screw 4 and so as not to contact the local exhaust duct 50 described later. When viewed in a plane, it extends from the ball screw 4 to the back side and is bent at a right angle toward the arm 3 so that it can be arranged close to the right side. As shown in FIG. 7, on the back side (case 25 side) of the portion bent at right angles in the support portion 3a, the arm 3 is controlled to move up and down with the ball screw 4 around the vertical axis. Further, a guide portion 3c is formed in the housing 25 so as to be fitted to a rail 3b formed along the vertical direction.

  As shown in FIG. 3, the arm 3 includes five forks (also referred to as a substrate holding unit or pick) 31 that respectively support the wafer W from below, and an advancing / retracting unit (carrying substrate) that holds the forks 31 so as to freely advance and retract. ) 32, and is configured to be rotatable around a vertical axis by a rotation mechanism 33 a provided on the lower side of the base portion 33 that supports the advance / retreat portion 32. The rotation mechanism 33a is connected to the other end of the support portion 3a described above. When the ball screw 4 rotates around the vertical axis, the arm 3 together with the support portion 3a is, for example, 0.4 m / s to 0 m. It is configured to move up and down at a lifting speed of 6 m / s. The lifting stroke of the arm 3 is 1.5 m, for example. The arm 3 is provided with an exhaust unit combined with a filter in order to exhaust particles generated in the arm 3 to the local exhaust duct 50 side, but the illustration is omitted here. .

  As shown in FIG. 1, the wafer boat 1 is configured to store a large number of, for example, 100 wafers W in a shelf shape. The wafer boat 1 is inserted into the reaction tube 2 and subjected to heat treatment, and an arm. 3 is moved up and down by a lifting mechanism (not shown) between the lower position where the wafer W is transferred. The height dimension of the area on which the wafer W is placed in the wafer boat 1 is, for example, 1 m. As will be described later, since the wafer W is transferred to the wafer boat 1, it can be said that the holder standby area 10b forms a part of the substrate transfer area 10a. In FIG. 2, reference numeral 1 a denotes an elevating mechanism for elevating the wafer boat 1.

And in the board | substrate conveyance area | region 10a and the holder waiting | standby area | region 10b, it is horizontal from the area | region of the other side (right side) which opposes the said area | region with respect to the area | region of the one side (left side) where the ball screw 4 mentioned above is arrange | positioned. A laminar gas flow is formed so as to extend in the front-rear direction and in the length direction of the ball screw 4 (wafer boat 1). Specifically, on the right side of each region 10a, 10b, as shown in FIG. 2, in order to supply clean gas such as air (air) or N ₂ (nitrogen) gas to the regions 10a, 10b, Box-shaped gas supply sections 34 combined with filters (filter media) 35 are provided, for example, at two locations so as to be separated from each other in the front-rear direction. As schematically shown in FIG. 6, the lower end portions of these gas supply portions 34 form gas inlets in order to form a circulation flow in which the gas circulates by a fan 42 described later in each region 10a, 10b. Each has an opening. Note that when nitrogen gas is used as the clean gas, the apparatus is actually provided with a supply pipe for supplying the clean gas to the atmosphere in the housing 25 and an exhaust pipe for exhausting the atmosphere. However, drawing is omitted here.

  On the left side surface of these gas supply units 34, the filter 35 described above extends in the longitudinal direction of the wafer boat 1 and in the front-rear direction in order to remove particles from the gas flowing through the gas supply unit 34. Each is formed along. Accordingly, the gas supply unit 34 is configured to supply clean gas to the regions 10 a and 10 b via the filter 35.

  Here, of the two gas supply units 34 described above, the “first” and the gas supply unit 34 on the front side (wafer boat 1 side) and the gas supply unit 34 on the back side (arm 3 side) in FIG. The layout of these two gas supply units 34 and 34 will be described below with “second” attached. Two gas recovery ducts 36 and 36 are arranged on the left side of the wafer boat 1 so as to face the first gas supply unit 34, and so as to face the second gas supply unit 34. Similarly, two gas recovery ducts 36 are disposed on the left side of the arm 3. Thus, four gas recovery ducts 36 are arranged inside the housing 25.

  Each of the gas recovery ducts 36 is formed so that a length dimension in the height direction is, for example, about 1.7 m, and the inner region has a hollow box shape. A gas suction port 37 for taking in the gas supplied from the gas supply unit 34 to each of the regions 10 a and 10 b is provided in the right wall surface of the gas recovery duct 36 along the length direction of the wafer boat 1. It is formed as a mouth. With respect to these four gas recovery ducts 36, the symbols “36a”, “36b”, “36c”, and “36d” are attached from the front side to the back side, respectively, so that the wafer boat 1 described above can be moved up and down. The elevating mechanism 1a is disposed between the gas recovery ducts 36a and 36b.

  Although simplified in FIG. 2 and the like, the gas suction port 37 is formed to face the first gas supply unit 34 side and the wafer boat 1 side as shown in FIG. Further, the gas suction ports 37 are formed in two rows on the left and right sides in such a manner that the quantity decreases from the upper side to the lower side in order to equalize the amount of gas taken in the vertical direction. A mechanical cover (not shown) made of a metal plate in which a large number of slit-like gas flow ports for allowing gas to flow is formed on the gas recovery ducts 36a to 36d in the respective regions 10a and 10b. However, the illustration is omitted.

  Each gas recovery duct 36 has a lower end opened to form a gas outlet, and a gas circulation path 41 is provided below the floor 5 so as to communicate with the gas outlet. Is arranged. That is, the gas circulation path 41 extends horizontally between the right side and the left side on the lower side of the floor surface 5, and has a substantially box shape in which the right end and the left end are opened. Yes. The gas circulation path 41 is provided at two locations on the front side and the back side. First, the gas circulation path 41 on the front side will be described. The opening on the left side of the gas circulation path 41 has a gas recovery duct. The lower end side openings of 36a and 36b are airtightly connected. Further, the opening on the right side of the gas circulation path 41 on the front side extends toward the first gas supply unit 34. As schematically shown in FIG. 6, for example, a heat exchanger 41 a in which plate-like metal plates are disposed in parallel with each other is accommodated in the gas circulation path 41, and a gas recovery duct 36 a is accommodated. , 36b can be cooled. The gas circulation path 41 has a cooling pipe (not shown) extending from a cooling device such as a chiller in order to cool the heat exchanger 41a heated by the gas flowing into the gas circulation path 41. It is connected.

  Between the opening on the right side of the gas circulation path 41 on the near side and the opening on the lower end side of the first gas supply unit 34, a fan (in detail, a sirocco fan) Is housed in an airtight manner. Then, when gas is supplied to the lower end opening of the gas supply unit 34 by the fan 42, particles are removed from the gas by a filter 35 provided in the gas supply unit 34, as schematically shown in FIG. Then, it is discharged over the height direction toward the holder waiting area 10b to become a horizontal flow. Next, the horizontal flow flows into the gas recovery ducts 36 a and 36 b and is returned to the fan 42 while being cooled via the gas circulation path 41. In this way, a circulation flow is formed through the gas supply unit 34, the holder standby region 10 b, the gas recovery ducts 36 a and 36 b, the gas circulation path 41, and the fan 42. Therefore, it can be said that the circulation path 41, the fan 42, and the first gas supply unit 34 are provided in common for the two gas recovery ducts 36a and 36b. The fan 42 is driven so that the gas flow in the holder standby region 10b becomes a laminar flow, that is, an extremely slow flow rate of, for example, 0.2 m / s to 0.5 m / s so as not to wind up particles. Conditions (such as the number of rotations of rotating blades) have been adjusted. These gas supply unit 34, fan 42, gas circulation path 41, and gas recovery ducts 36a and 36b constitute a laminar flow forming unit.

  Next, the second gas supply unit 34 and the gas circulation path 41 on the back side will be described. Also for the second gas supply unit 34, two gas recovery ducts 36c and 36d are arranged so as to face the second gas supply unit 34, similarly to the first gas supply unit 34 described above. In addition, a gas circulation path 41 and a fan 42 shared by the second gas supply unit 34 and the two gas recovery ducts 36c and 36d are provided below the floor surface 5. The two gas recovery ducts 36 c and 36 d in the second gas supply unit 34 are arranged so as to be separated from each other in the front-rear direction via the ball screw 4. Of these two gas recovery ducts 36c and 36d, the gas recovery duct 36c on the near side is disposed so as to face the second gas supply unit 34 via the back side portion of the wafer boat 1. . Further, the gas recovery duct 36d on the back side of the gas recovery ducts 36c and 36d is opposed to the second gas supply unit 34 through a region where the wafer W is unloaded into the housing 25 by the arm 3. Has been placed.

  Here, between the ball screw 4 and the gas recovery duct 36c on the near side (wafer boat 1 side) of the ball screw 4, as shown in FIGS. In order to suck in, a local exhaust duct (scavenging duct) 50 in which a gas suction port 53 of gas is formed is arranged along the length direction of the ball screw 4. That is, the local exhaust duct 50 is adjacent to the gas recovery duct 36c and surrounds a region where the ball screw 4 is placed, and when viewed in plan, the region is recessed in a rectangular shape to form a substantially L shape. . In other words, the local exhaust duct 50 is arranged so that one end side comes into contact with the housing 25 when viewed in a plane, and the other end side extends rightward toward the gas supply unit 34, and the ball screw 4 and the gas In the region between the supply section 34, it is bent and extended at a right angle toward the back side. Therefore, as shown in FIG. 3, when the ball screw 4 is viewed from the wafer boat 1, the local exhaust duct 50 is covered by the local exhaust duct 50 along the length direction (so as not to be seen). ) Is arranged. In other words, the local exhaust duct 50 is disposed between the ball screw 4 and the substrate transfer region 10a, and is also disposed on the right side surface of the left and right side surfaces when the arm 3 side is viewed from the ball screw 4. Yes. In FIG. 3, the local exhaust duct 50 is partially cut away.

  As shown in FIG. 5, the lower end portion of the local exhaust duct 50 opens in the same manner as the gas recovery ducts 36 a to 36 d and is airtightly connected to the opening end of the gas circulation path 41 in the second gas supply unit 34. Has been. Therefore, in addition to the two gas recovery ducts 36c and 36d facing the second gas supply unit 34, the local exhaust duct 50 also exhausts (recovers) the gas supplied from the second gas supply unit 34. It can be said that it has a role. That is, the local exhaust duct 50 is provided in common with the gas recovery ducts 36 c and 36 d on the front and rear sides of the local exhaust duct 50 with respect to the second gas supply unit 34. In this local exhaust duct 50, the side surface facing the ball screw 4 and the surface extending in the left-right direction and the surface perpendicular to the surface are referred to as a first wall surface portion 51 and a second wall surface portion 52, respectively, as shown in FIG. In addition, the separation dimensions d1 and d2 between the wall surface portions 51 and 52 and the ball screw 4 are set to a small dimension of, for example, 10 mm to 50 mm in order to suppress scattering of organic substances and particles generated from the ball screw 4. In FIG. 5, the size of each member such as the arm 3 is schematically shown, and only one wafer W and fork 31 are drawn.

As shown in FIG. 4, the first wall surface portion 51 and the second wall surface portion 52 have a slit-like gas suction port 53 extending in the vertical direction along the length direction of the ball screw 4 and along the horizontal direction. Are arranged at a plurality of places, for example, two places. Thus, the gas suction ports 53 are each formed to face the ball screw 4 side.
Here, a member for forming a laminar flow of gas in the gas recovery duct 36c on the front side of the gas recovery ducts 36c and 36d facing the second gas supply unit 34 (the second gas supply unit 34, the gas The collection duct 36c, the fan 42, and the gas circulation path 41) will be referred to as a first laminar flow forming portion. In addition, a member for forming a laminar flow of gas through the local exhaust duct 50 (the local exhaust duct 50, the second gas supply unit 34, the fan 42, and the gas circulation path 41) is replaced with a second laminar flow forming unit. In this example, it can be said that the fan 42 and the gas circulation path 41 are shared in the first laminar flow forming portion and the second laminar flow forming portion. The arm 3, the ball screw 4 and the local exhaust duct 50 described above constitute a substrate transfer facility.

  The length direction of the ball screw 4 in order to prevent the organic matter and particles generated from the ball screw 4 from scattering toward the arm 3 side at the back side portion of the second wall surface portion 52 of the local exhaust duct 50. A substantially plate-shaped covering member 54 extending along the line is provided. Specifically, as shown in FIG. 7, the covering member 54 has a base end portion that extends from the back side portion toward the arm 3 side and is bent at a right angle toward the left side when viewed in a plane. doing. Accordingly, when the arm 3 side is viewed from the ball screw 4, the local exhaust duct 50 and the covering member 54 are arranged so that the ball screw 4 is not visible as much as possible from the wafer W transferred by the arm 3.

  This vertical heat treatment apparatus is provided with a control unit 71 composed of a computer that outputs a control signal in order to control the operation of the entire apparatus. In the memory of the control unit 71, a heat treatment program (not shown) for taking out the wafer W from the FOUP 11 and transporting it to the wafer boat 1 and performing heat treatment in the reaction tube 2 is stored. This program is installed in the control unit 71 from the storage unit 72 which is a storage medium such as a hard disk, a compact disk, a magneto-optical disk, a memory card, and a flexible disk.

  Next, the operation of this apparatus will be described. First, in this apparatus, heat treatment is sequentially performed on a large number of wafers W, and all the processed wafers W are returned to the original FOUP 11, and the wafer boat 1 is located below the reaction tube 2. It is assumed that the position is empty (the wafer W is not loaded). At this time, the furnace port which is the lower end opening of the reaction tube 2 is hermetically closed by a lid (not shown). Further, the first supply unit 34 and the second gas supply unit 34 form a very slow laminar flow toward the regions 10a and 10b in the height direction and in the front-rear direction.

  Specifically, the airflow supplied from the first supply unit 34 to the holder standby region 10b is recovered by the gas recovery ducts 36a and 36b facing the first supply unit 34, and the gas circulation path 41 and A circulating flow is formed via the fan 42. Further, the airflow supplied from the second gas supply unit 34 is recovered by the gas recovery ducts 36c and 36d and the local exhaust duct 50 facing the second gas supply unit 34, and similarly, the gas circulation path 41 and A circulating flow is formed via the fan 42. Accordingly, in the region where the ball screw 4 is disposed, as shown in FIGS. 2, 7 and 8, the clean gas discharged from the second gas supply unit 34 is on the upper side of the support unit 3a supporting the arm 3. It passes through the region and the region on the lower side, and flows into the local exhaust duct 50 so as to go around the covering member 54 provided on the back side of the local exhaust duct 50. In FIG. 8, only one wafer W and the fork 31 are drawn.

  Next, the FOUP 11 is placed on the transfer stage 22 via the carrier transfer machine 23, the shutter 27 is opened, and, for example, five wafers W are taken out to the substrate transfer region 10a side by the arm 3 via the transfer port 28. . Specifically, the fork 31 is moved into the FOUP 11 at a position slightly below each wafer W, then the fork 31 is lifted slightly to receive the wafer W, and then the fork 31 is moved backward. Then, the fork 31 is reversed so that the traveling direction of the fork 31 faces the wafer boat 1, and the arm 3 is raised or lowered to a position corresponding to the holding position of the wafer W in the wafer boat 1. Thereafter, as shown in FIG. 9, the fork 31 is operated in an order reverse to the order of taking out the wafers W from the FOUP 11, and the wafers W are transferred to the wafer boat 1.

In this wafer W loading process, when the arm 3 moves up and down, the ball screw 4 rotates around the vertical axis as described above, so that it is applied to the ball screw 4 by the centrifugal force of the ball screw 4 as shown in FIG. The lubricating oil (oil) such as organic matter tends to scatter as particles, for example. However, a local exhaust duct 50 is disposed between the ball screw 4 and the wafer W on the arm 3, and the gas suction port 53 of the local exhaust duct 50 faces the ball screw 4 and the ball screw 4. It is formed along the length direction. Therefore, particles from the ball screw 4 toward the substrate transfer region 10 a collide with the local exhaust duct 50 and are taken into the local exhaust duct 50. In addition, particles that go around the side of the local exhaust duct 50 and go toward the substrate transport region 10 a are also taken into the local exhaust duct 50 by the negative pressure formed by the local exhaust duct 50. Thus, the particles generated from the ball screw 4 can be prevented from being scattered to the surroundings even when the lifting / lowering speed of the arm 3 is as high as 0.6 m / s, that is, even when the rotational speed of the ball screw 4 is about 1300 rpm. The gas is sucked by the local exhaust duct 50 together with the gas flowing from the second gas supply unit 34.
On the other hand, in the substrate transfer area 10a and the holder standby area 10b, since the laminar flow is formed by the gas supply units 34 and 34, even if particles are attached to the arm 3 or the like, for example, the particles are wound up. It can be suppressed.

  In this manner, the remaining wafers W are similarly transferred from the FOUP 11 to the wafer boat in units of five, and when the FOUP 11 becomes empty, another FOUP 11 is placed on the transfer stage 22, and about 100 wafers, for example, are placed on the wafer boat 1. The wafer W transfer operation is repeated until the wafer W is loaded.

  Subsequently, when the transfer operation of the wafer W is completed, the wafer W is subjected to heat treatment. That is, after the wafer boat 1 is inserted into the reaction tube 2, the furnace port of the reaction tube 2 is airtightly closed. Next, while setting the inside of the reaction tube 2 to a vacuum atmosphere, a processing gas is supplied to each wafer W heated to, for example, about 600 ° C. by a heater (not shown). Thereafter, when the heat treatment on the wafer W is completed, a lid body (not shown) that hermetically closes the lower end opening, which is the furnace port of the reaction tube 2, is retracted to the side, and the wafer boat 1 is held in the holder waiting area 10 b. Lower towards.

  As described above, the high-temperature heat treatment is performed on the wafer W, and thus the wafer boat 1 and the wafer W that have descended to the holder waiting area 10b are still at a high temperature. However, since the gas supply unit 34 and the gas recovery ducts 36a to 36d are arranged facing left and right, the laminar flow in which the clean gas flows in the horizontal direction in a laminar flow in the holder standby region 10b is in the height direction. And over the front-rear direction. Thus, the wafer boat 1 and the wafer W are quickly cooled by the clean gas flowing through the heat exchanger 41a.

  On the other hand, depending on the processing performed on the wafer W, the adhered matter adhering to the wafer boat 1 and the wafer W may float. However, while the laminar flow described above suppresses the rolling of other particles, particles suspended in the atmosphere are exhausted by a circulating flow of clean gas and removed by a filter provided in the gas supply unit 34. Is done.

  Next, when the temperature of the wafer boat 1 and the wafer W is lowered to a temperature at which the arm 3 can be accessed, the processed wafers W are sequentially transferred to the FOUP 11 using the arm 3 by the unloading operation opposite to the loading operation to the wafer boat 1. Carry in. Also in this unloading process, particles generated in the ball screw 4 are exhausted by the local exhaust duct 50, and scattering to the substrate transport region 10a is suppressed.

  According to the above-described embodiment, the gas suction port 53 for sucking particles is formed between the arm 3 and the ball screw 4 so as to face the ball screw 4 side and along the length direction of the ball screw 4. A local exhaust duct 50 is arranged. For this reason, it is possible to suppress scattering of particles generated from the ball screw 4 on the substrate transfer region 10a side, so that contamination of the wafer W can be suppressed. Therefore, when the atmosphere in which the ball screw 4 is placed is locally exhausted, it is only necessary to arrange the local exhaust duct 50 without providing a separate exhaust unit. And the area | region which has arrange | positioned this local exhaust duct 50 is an area | region where the ball screw 4 is arrange | positioned, and is, so to speak, a dead space. Therefore, scattering of particles from the ball screw 4 can be suppressed while suppressing an increase in size of the apparatus. Further, as described above, the arm 3 can be moved up and down at high speed while suppressing the scattering of particles, and when the wafer W is cooled, the laminar flow described above is ensured (the rising air current due to the heat of the wafer W). Since the wafer W can be quickly cooled (suppressing generation), the throughput can be improved.

  Further, since the wall surface portions 51 and 52 of the local exhaust duct 50 are close to the ball screw 4 as described above, it can be sucked before particles are scattered from the ball screw 4, and the ball screw It becomes easy to make the area where 4 is placed locally negative pressure. Therefore, scattering of particles can be suppressed satisfactorily.

  Here, in the example described above, the local exhaust duct 50 is configured in an L shape when viewed in plan, but may be formed so as to surround the ball screw 4. Specifically, as shown in FIGS. 11 and 12, the local exhaust duct 50 is formed so as to extend in the front-rear direction when viewed in a plan view, and the front end and the back side of the local exhaust duct 50. Are extended toward the housing 25 side (left side), and an area where the ball screw 4 is placed is sandwiched between these both ends. That is, the local exhaust duct 50 is arranged between the ball screw 4 and the substrate transfer area 10a, and the local exhaust duct 50 is also arranged on the left and right side portions when the arm 3 side is viewed from the ball screw 4. In other words, it is formed in a U-shape. And about the support part 3a which supports the arm 3, while extending from the back side (left side) of the ball screw 4 toward the housing | casing 25 side, it goes around the edge part of the local exhaust duct 50 from the outer side, and goes to the arm 3. Bend like so.

  When the local exhaust duct 50 is formed in this way, when viewed from the ball screw 4 on the substrate transfer region 10a side, the local exhaust duct 50 is disposed on both the left and right sides and the front, and the housing 25 is positioned on the back side. Yes. Therefore, the region where the ball screw 4 is placed is roughly surrounded by the local exhaust duct 50 and the housing 25, and it becomes easy to form a negative pressure in the region, so that the scattering of particles can be further suppressed.

  Further, when the local exhaust duct 50 is disposed so as to face the left and right sides and the front side when the substrate transfer area 10a side is viewed from the ball screw 4, as shown in FIGS. 13 and 14, the movable range of the arm 3 is set. You may form the opening part 50a extended in an up-down direction along the side surface side of the local exhaust duct 50 along. In this case, the support portion 3a is arranged to extend toward the arm 3 through the opening 50a. FIG. 14 shows a cross section in a horizontal plane in which the opening 50a is formed in FIG.

  As described above, when the local exhaust ducts 50 are arranged on the left side, the right side, and the front side when the substrate transfer area 10a side is viewed from the ball screw 4, the left side local exhaust duct 50, the right side local exhaust duct 50, and the front side are arranged. The local exhaust ducts 50 on the side may be arranged independently of each other. That is, a wall surface portion may be formed between the ducts 50 and 50 adjacent to each other to partition the ducts 50 and 50 adjacent to each other. In this case, the internal regions of these ducts 50 communicate with each other through the gas circulation path 41 on the lower side of the floor surface 5. Accordingly, in FIGS. 11 to 14 described above, when the left local exhaust duct 50 and the right local exhaust duct 50 are respectively referred to as auxiliary exhaust ducts, the front local exhaust duct 50 and two auxiliary exhaust ducts are referred to. Can be said to be standardized.

  Furthermore, as shown in FIGS. 15 and 16, the local exhaust duct 50 may be formed in a substantially box shape so as to be positioned between the ball screw 4 and the substrate transfer region 10a. Even in this case, the gas suction port 53 is formed so as to face the ball screw 4 side and along the length direction of the ball screw 4.

  Here, when viewed in a plan view, a path through which an unprocessed wafer W is taken out from the FOUP 11 and transferred to the wafer boat 1 is referred to as a “transport path”, and each of the above examples. The arrangement position of the local exhaust duct 50 will be described together. The timing when the particles try to scatter from the ball screw 4 is when the ball screw 4 rotates around the vertical axis, that is, when the arm 3 accesses the wafer boat 1 or the FOUP 11. If a very slow laminar flow is formed in the substrate transfer region 10a as described above, the particle scattering speed may be higher than the gas flow velocity in the laminar flow depending on the number of rotations of the ball screw 4. . As already described, it is difficult to increase the laminar gas flow velocity in order to prevent particles from rolling up. Therefore, the local exhaust duct 50 is preferably provided between the ball screw 4 and the position of the wafer W on the arm 3 when the arm 3 moves up and down via the ball screw 4 in the transfer path. . When the arm 3 accesses the FOUP 11, the height direction (lifting stroke) of the arm 3 is very small enough to straddle the height position where a certain wafer W is placed. The dimensions are different. On the other hand, when the arm 3 accesses the wafer boat 1, the arm 3 that holds the wafer W at a position slightly behind the wafer boat 1 is the loading position of the wafer W in the height direction of the wafer boat 1. Ascend and descend greatly according to

  Therefore, it can be said that particles are more easily generated when accessing the wafer boat 1 than when accessing the FOUP 11. Therefore, the local exhaust duct 50 is preferably provided between the ball screw 4 and the position on the wafer boat 1 side among the position on the FOUP 11 side where the wafer W moves up and down and the position on the wafer boat 1 side. Further, the local exhaust duct 50 is provided at least on the front side and the right side of the ball screw 4 as shown in FIGS. 2 and 11 to 14 so that the wafer W at the position on the wafer boat 1 side cannot be seen from the ball screw 4. Is preferably provided. As already described with reference to FIGS. 11 to 14, when the local exhaust duct 50 is also provided on the left side of the ball screw 4, the scattering of particles is further suppressed.

  Further, as shown in FIG. 17, the local exhaust duct 50 has a position where the wafer W moves up and down when the wafer W is transferred to the wafer boat 1 (a position slightly behind the wafer boat 1), The local exhaust duct 50 may be provided at a position shifted from the straight line connecting the ball screw 4 to the back side. Even in this case, the particles to be scattered from the ball screw 4 are sucked from the gas intake ports 53 formed on the front side and the left side of the local exhaust duct 50 in the middle of diffusing to the substrate transfer region 10a side. The Therefore, regarding the local exhaust duct 50, “provided between the ball screw 4 and the substrate transfer region 10 a” means that it is provided between at least a part of the transfer path and the ball screw 4. . 11 and 12, the local exhaust duct 50 can be said to be provided between the substrate transfer region 10a and the ball screw 4 over the length direction of the transfer path.

  Further, as an elevating mechanism for elevating and lowering the arm 3, for example, a belt conveyor or the like may be used instead of the ball screw 4. Further, the configuration for raising and lowering the wafer boat 1 as a vertical heat treatment apparatus has been described. However, an area for placing the wafer boat 1 is provided on the side of the arm 3 (for example, the right side). A configuration for delivering the wafer W may also be used. In addition to the vertical heat treatment apparatus, the elevating mechanism and the local exhaust duct 50 described above are, for example, a coating / developing apparatus provided with a plurality of processing units for performing a coating liquid coating process and a developing process on the wafer W. Further, the present invention may be applied to an arm that transfers the wafer W between these processing units.

W Wafer 1 Wafer boat 2 Reaction tube 3 Wafer transfer arm 4 Ball screw 10 Transfer area 34 Gas supply part 35 Gas discharge port 36 Gas recovery duct 37 Gas suction port 50 Local exhaust duct 53 Gas suction port

Claims (7)

An elevating base, an elevating mechanism for elevating and lowering the elevating base, and a holding portion for holding and transporting the substrate; the elevating base extends to one side of the left and right when viewed from the elevating mechanism and is further bent to the front side A substrate transport mechanism configured to extend to the front end portion and to be provided with the holding portion ,
Between the substrate transport area where the substrate is transported by the holding unit and the lifting mechanism, the lifting mechanism is located along the lifting area with the lifting area of the lifting base in front of the lifting mechanism. An exhaust duct provided independently of the base body ,
The substrate transport facility , wherein the exhaust duct is formed so that a gas suction port for sucking particles generated from the lifting mechanism faces the lifting mechanism side and along the lifting area . An auxiliary exhaust duct provided independently of the lifting base so as to face the lifting region of the lifting base on the other side opposite to the left and right sides from which the lifting base extends as seen from the lifting mechanism. Prepared,
The auxiliary exhaust duct, substrate transport according to claim 1, wherein the gas suction port for sucking particles generated from the lifting mechanism is formed along and lifting region so as to face the elevating mechanism side Facility. 3. The substrate transfer equipment according to claim 2, wherein the exhaust duct and the auxiliary exhaust duct are shared so that the internal areas of the exhaust duct and the auxiliary exhaust duct communicate with each other.   4. The substrate transfer facility according to claim 1, wherein the elevating mechanism is a ball screw mechanism. A circulation path through which gas sucked from the exhaust duct passes;
A gas supply unit configured to supply the gas returned through the circulation path to the substrate transfer region and form a layered air flow toward the exhaust duct via the substrate transfer region. The substrate transfer equipment according to claim 1. In the substrate transfer area, a substrate holder for holding the substrate in a shelf shape and carrying it in and out of a vertical reaction tube for performing heat treatment on the substrate is disposed,
6. The substrate transfer facility according to claim 1, wherein the substrate transfer mechanism is for transferring a substrate to and from the substrate holder.   The exhaust duct is provided between a position of a substrate on the holding unit when the holding unit moves up and down via the lifting mechanism and the lifting mechanism. The board | substrate conveyance equipment as described in any one of.

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