JP2005033118A - System and method for purging - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system and method for purging, which can facilitate and ensure an operation for removing contaminants or the like from wafers accommodated in an FOUP. <P>SOLUTION: With a cover 4 being separated from a body of the FOUP 2, a gas supply nozzle 21 is disposed in front of an opening so that a cleaning gas may be supplied to the entire surface regions of the wafers 1. With this positional relationship being maintained, the nozzle 21 is allowed to move along the direction in which the wafers 1 are stacked. Thus, the cleaning gas can be sprayed from the nozzle 21 to the individual wafers, thereby removing contaminants or the like from the wafers 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a product container used for housing an article in a manufacturing process of an article such as a semiconductor, a panel for a flat panel display, an optical disk or the like, which is processed in a highly clean environment. More specifically, the present invention relates to a method for cleaning the interior of a so-called FOUP (front-opening unified pod), which is used as an object to be contained in the processing step of the above-described article, mainly a 300 mm semiconductor wafer. .

  Up to now, in the manufacturing process of semiconductor devices, the entire factory for performing various processes on wafers has been converted into a clean room, which corresponds to the high cleanliness required in the process. However, as the diameter of the wafer increases, it is a problem in terms of cost to obtain a configuration environment in such a countermeasure, and in the past few years, a mini-environment (highly clean for each processing apparatus) ( Microenvironment) means to secure the space.

  Specifically, it does not increase the cleanliness of the whole factory, but keeps only the inside of each processing apparatus in the manufacturing process and the storage container (hereinafter referred to as a pod) during the movement at a high cleanliness. . As mentioned above, this pod is collectively called FOUP. In this way, by purifying only a small space with high cleanliness, the same effect as when the entire factory is converted to a clean room is obtained, and the capital investment and maintenance costs are reduced to realize an efficient production process.

  Hereinafter, a semiconductor processing apparatus and the like corresponding to a so-called mini-environment method that is actually used will be briefly described. FIG. 8 shows the entire semiconductor wafer processing apparatus 50. The semiconductor wafer processing apparatus 50 mainly includes a load port unit 51, a transfer chamber 52, and a processing chamber 59. Each joining portion is partitioned by a partition 55a and a cover 58a on the load port side, and a partition 55b and a cover 58b on the processing chamber side. In order to discharge dust in the transfer chamber 52 in the semiconductor wafer processing apparatus 50 and maintain high cleanliness, an air flow is generated from the upper side to the lower side of the transfer chamber 52 by a fan (not shown) provided on the upper side. Yes. As a result, the dust is always discharged downward.

  On the load port portion 51, a pod 2 as a storage container for a silicon wafer or the like (hereinafter simply referred to as a wafer) is installed on a table 53. As described above, the inside of the transfer chamber 52 is kept highly clean for processing the wafer 1, and the robot arm 54 is provided in the inside thereof. The wafer is transferred between the inside of the pod 2 and the inside of the processing chamber 59 by the robot arm 54. The processing chamber 59 normally includes various mechanisms for performing processing such as thin film formation and thin film processing on the wafer surface and the like, but these configurations are not directly related to the present invention. Description is omitted.

  The pod 2 has a space for accommodating the wafer 1 as an object to be processed therein, and includes a box-shaped main body 2a having an opening on one surface and a lid 4 for sealing the opening. ing. A shelf having a plurality of steps for stacking the wafers 1 in one direction is arranged inside the main body 2a, and each of the wafers 1 placed therein is accommodated in the pod 2 with a constant interval. . In the example shown here, the direction in which the wafers 1 are stacked is the vertical direction. An opening 10 is provided on the transfer port 52 side of the transfer port 52. The opening 10 is arranged at a position facing the opening of the pod 2 when the pod 2 is arranged on the load port unit 51 so as to be close to the opening 10. The transfer chamber 52 is provided with an opener 3 to be described later in the vicinity of the opening 10 inside.

  9A and 9B show an enlarged side cross-sectional view of an opener 3 portion in a conventional apparatus and a front view of the opener 3 viewed from the transfer chamber 52 side, respectively. FIG. 10 shows a schematic side sectional view of the state where the lid 4 is removed from the pod 2 using the opener 3. The opener 3 includes a door 6 and a door arm 42. A fixing member 46 is attached to the door 6, and the door 6 is rotatably connected to one end of the door arm 42 via the fixing member 46. The other end of the door arm 42 is rotatably supported with respect to the pivot 40 via the pivot 40 with respect to the tip of the rod 37 which is a part of the air-driven cylinder 31.

  A through hole is provided between the one end and the other end of the door arm 42. A fulcrum 41 is configured by a pin (not shown) passing through the hole and a hole of the fixing member 39 fixed to the support member 60 of the movable portion 56 that moves the opener 3 up and down. Therefore, the door arm 42 can rotate around the fulcrum 41 according to the expansion and contraction of the rod 37 by driving the cylinder 31. A fulcrum 41 of the door arm 42 is fixed to a support member 60 provided on a movable portion 56 that can be moved up and down. The door 6 has holding ports 11a and 11b, and can hold the lid 4 of the pod 2 by vacuum suction.

  When processing the wafer 1 with these configurations, the wafer 1 is first placed on the table 53 so as to be close to the transfer chamber opening 10, and the lid 4 is held by the door 6. When the rod of the cylinder 31 is contracted, the door arm 42 moves away from the transfer chamber opening 10 around the fulcrum 41. By this operation, the door 6 rotates together with the lid 4 to remove the lid 4 from the pod 2. This state is shown in FIG. Thereafter, the movable portion 56 is lowered to transport the lid 4 to a predetermined retracted position.

  Normally, the inside of the pod 2 in a state where a wafer or the like is accommodated is filled with highly clean dry nitrogen or the like to prevent entry of contaminants, oxidizing gas, etc. into the pod. . However, since the pod also accommodates the wafer after passing through the processing chamber, there may be a case where contaminants or the like adhere to the wafer in the processing chamber or the like and are brought into the pod. When such a contaminant or the like is brought into the next processing chamber, there may be a case where the desired wafer processing that should be originally performed is not performed through this processing chamber. For this reason, it is necessary to remove these contaminants when the wafer is transferred from the pod to the transfer chamber.

  In the conventional FOUP, in order to meet the demand, an air supply hole for introducing purge gas into the pod and an exhaust hole for discharging are provided at the bottom. These air supply and exhaust holes are respectively connected to an air supply hole and an exhaust hole for purge gas provided on a support base on which the pod is placed. As an actual operation, high-pressure gas controlled to be highly clean is introduced into the pod from the support base side through these air supply holes. At the same time, gas, contaminants, and the like that existed inside the pod are discharged to the outside of the pod through these exhaust holes. By this operation, the contaminants brought into the pod were removed.

  However, it is considered that the gas flow mainly passes through the vicinity of the outer periphery of the wafer, which is easy to pass by simply introducing high-pressure gas from the bottom of the pod. Therefore, it seems difficult to pass a gas having a sufficient flow rate with respect to the upper and lower surfaces of individual wafers held at minute intervals. However, contaminants and the like are mainly attached to the upper surface or the lower surface of the wafer, and it is considered difficult to sufficiently remove the contaminants and the like by the conventional method.

  As a method for reliably removing contaminants attached to the wafer, a method disclosed in [Patent Document 1] has been proposed. In this method, a space for accommodating the opener is provided separately from the transfer chamber. The space has a gas supply port in a portion located in front of the opening of the pod. Clean gas is supplied from the gas supply port toward the inside of the pod, and the clean gas that circulates inside the pod and flows out from the lower part of the pod to the space is exhausted from the lower part of the space. By using the above configuration and circulating a clean gas inside the pod, it is possible to remove contaminants and the like more reliably than in the conventional method.

  [Patent Document 2] discloses a method of introducing clean gas between wafers held inside a pod. In this method, a gas introduction flow path and a gas discharge flow path are provided inside the pod to communicate with each of the groove portions for accommodating individual wafers. By spraying a clean gas on the surface of each wafer through the gas introduction flow path and exhausting the clean gas containing contaminants etc. through the gas discharge flow path, it is more reliable. It is possible to remove various pollutants.

JP 2003-45933 A JP 11-251422 A JP 2002-353293 A

  The method disclosed in [Patent Document 1] can be expected to have a certain effect with respect to the reduction of humidity and oxidizing gas inside the pod and prevention of organic contamination. However, it is still difficult to effectively replace the gas or the like existing between the wafers held in a minute space. Therefore, it seems to be similarly difficult to obtain the effect of removing contaminants attached to the upper and lower surfaces of the wafer.

  According to the method disclosed in [Patent Document 2], it is considered possible to remove contaminants attached to the upper and lower surfaces of the wafer. However, it is difficult to keep the inner diameter of the gas introduction flow path large due to the actual configuration. For this reason, there is a difference in the pressure of the gas introduced to the wafer surface or the time of introduction at a predetermined pressure between the upstream side and the downstream side of the flow path, and the contaminant removal effect depends on the holding position of the wafer. May be different.

  In addition, the arrangement of the support base, the shape of the pod, and the supply and discharge holes of the clean gas for purging the pod are almost standardized in the semiconductor manufacturing industry. Therefore, the pod disclosed in [Patent Document 2] which requires a configuration different from this standard has a problem that it cannot be shared with a currently used support base or the like.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a FOUP purge method and a purge apparatus capable of effectively removing contaminants and the like adhering to a wafer. .

  In order to solve the above-described problems, a purge apparatus according to the present invention includes an opening and a main body composed of a plurality of shelves arranged in a predetermined direction on which the objects to be placed are respectively placed, and the opening is separable from the main body. A purging device that performs a purging operation by blowing a predetermined gas on an object accommodated in a pod that includes a lid that closes, and is separated from an end of the object to be accommodated by a predetermined distance. A gas supply nozzle that blows a predetermined gas substantially uniformly on substantially the entire area of the surface extending perpendicularly to the predetermined direction of the object, and supports the gas supply nozzle to move the gas supply nozzle in the predetermined direction. It is characterized by having a drivable support member.

  In the purge apparatus described above, the support member is preferably a member that attaches / detaches the lid from the main body of the pod. Moreover, it is preferable that the timing at which the predetermined gas is blown out from the gas supply nozzle is synchronized with the timing when the support member passes through the plane in which the object is extended when the support member moves in the predetermined direction. Furthermore, the gas supply nozzle blows out a predetermined gas to a region surrounded by a plane parallel to the plane in which the object is extended and a plane extending downward at a predetermined angle with respect to the plane. preferable.

  In the purge apparatus, the object to be accommodated corresponds to a wafer used for manufacturing a semiconductor or various articles to be processed in a highly clean environment. In addition, FOUP is an example of a pod that accommodates a semiconductor wafer. However, the pod is not limited to FOUP as long as it accommodates various articles. The state in which the lid is separated from the main body corresponds to a state in which the pod is placed on the load port and the wafer accommodated in the pod is transferred to the wafer processing apparatus via the load port. In addition, the purge operation described here means an operation for removing contaminants such as dust, organic matter, impurity elements, and oxidizing gas existing on the article. Mapping means an operation of detecting the presence / absence of a wafer accommodated in a shelf and associating it with shelf position information.

  In order to solve the above-described problem, the purging method according to the present invention is separable from the main body, which is composed of a plurality of shelves arranged in a predetermined direction on which the opening and the objects to be stored are respectively placed. A purging method for performing a purging operation by blowing a predetermined gas on an object accommodated in a pod having a lid that closes the opening, and a step of separating the lid from the main body, and a front surface of the opening being accommodated The step of moving the gas supply nozzle along a predetermined direction while maintaining a state spaced from the end of the object by a predetermined distance, and the gas supply nozzle extends in a direction perpendicular to the predetermined direction of the object to be accommodated. The method includes a step of purging the object to be contained by blowing a predetermined gas substantially uniformly over substantially the entire area of the surface.

  In the purge method described above, the gas supply nozzle is preferably fixed to a door used to remove the lid from the pod body. Moreover, it is preferable that the process of purging is performed in synchronism with the timing at which the object to be accommodated passes through the extending plane when the gas supply nozzle moves in a predetermined direction. Further, in the purging step, the gas supply nozzle supplies a predetermined gas between a plane parallel to the plane in which the object is extended and a plane extending downward at a predetermined angle with respect to the plane. It is preferable to blow out.

  In the purge method described above, the object to be accommodated corresponds to a wafer used for semiconductor manufacturing or various articles to be processed in a highly clean environment. In addition, FOUP is an example of a pod that accommodates a semiconductor wafer. However, the pod is not limited to FOUP as long as it accommodates various articles. The state in which the lid is separated from the main body corresponds to a state in which the pod is placed on the load port and the wafer accommodated in the pod is transferred to the wafer processing apparatus via the load port. In addition, the purge operation described here means an operation for removing contaminants such as dust, organic matter, impurity elements, and oxidizing gas existing on the article. Mapping means an operation of detecting the presence / absence of a wafer accommodated in a shelf and associating it with shelf position information.

  According to the present invention, it is possible for the gas supply nozzle to spray highly clean gas toward the entire area of the wafer surface at a predetermined distance from the wafer. Further, the gas supply nozzle is movable in the direction in which the wafers are stacked, and gas can be sprayed individually on each wafer. Therefore, it is possible to effectively and reliably remove contaminants such as dust and impurities adhering to the wafer surface. Further, the purge operation inside the pod can be performed at any time during the wafer processing by using the gas supply nozzle, and the wafer can be held in a more clean environment. In addition, the present invention can be implemented simply by adding a gas supply nozzle and a gas pipe to a load port door in an existing FOUP system, and can be easily and inexpensively attached to a standardized system. Is possible.

  An embodiment of the present invention will be described below with reference to the drawings. 1A to 1C relate to a schematic configuration of a purge apparatus according to the present invention, and are diagrams showing an outline of a state in which a pod, a wafer housed in a bod, and a purge apparatus according to the present invention are viewed from the side. FIG. 1A shows the start of the purge operation, FIG. 1B shows the middle of the purge operation, and FIG. 1C shows an enlarged view of the main part of the purge apparatus. 2A is a diagram showing an outline of the main part of the configuration shown in FIG. 1 and the configuration associated therewith as viewed from above, and FIG. 2B is a cross-sectional view of the main part of the purge device taken along a horizontal plane. It is a figure which shows the state which looked at this from upper direction. The pod originally includes various configurations such as a shelf for supporting the wafer, a seal member disposed between the lid and the pod, and the door is also associated with various configurations. However, since these configurations do not have a direct relationship with the present invention, detailed illustration and description thereof are omitted here.

  In the figure, a nozzle 21 capable of releasing clean gas is attached to the upper part of the door 6 in the opener in the direction indicated by the arrow in the figure. A gas supply line (not shown) is connected to the gas supply nozzle 21 so that a clean gas can be supplied to the nozzle in accordance with an external operation. As shown in FIG. 2B, the gas supply nozzle 21 includes a substantially tubular member 22 extending in a direction parallel to the surface of the wafer 1, and the tubular member 22 is a line formed in parallel with the surface of the wafer 1. It has the opening 22a formed in the shape. In addition, the clean gas is introduced into the inside of the member which is said to be lenient from a portion which is substantially the center of the tubular member 22 and does not face the opening 22a. The gas supply nozzle 21 is sequentially moved in the direction in which the wafers 1 are overlapped to supply clean gas between the wafers 1. As a result, the operation of removing contaminants and the like by the clean gas inside the front and back surfaces of the wafer and inside the pod 2 is performed. The door 6 is driven in parallel with the direction in which the wafers 1 are stacked. Therefore, the purge operation for the wafer 1 inside the pod 2 can be sequentially performed by discharging the clean gas from the gas supply nozzle 21 when the door 6 is driven.

  In the present embodiment, the center of the tubular member 22 in the gas supply nozzle 21 is separated from the opening end face of the pod body 2 by a predetermined distance L. The opening 22a has such a shape that the clean gas discharged from the opening 22a diffuses as shown in FIG. 2B in the horizontal direction and as shown in FIGS. 1A to 1C in the vertical direction. By providing an interval L between the tubular member 22 and the opening of the pod main body 2, clean gas is sprayed over the entire surface of the wafer 1 in the horizontal direction to remove contaminants and the like. Further, the flow rate of the gas discharged from the normal gas supply nozzle is the fastest in the vicinity of the nozzle opening, and rapidly decreases as the distance from the opening is increased. Therefore, when the gas is supplied from a position very close to the wafer edge, a large flow velocity difference between the upstream and downstream of the gas flow on the wafer surface may occur, resulting in a large difference in the removal efficiency of contaminants or the like, or extremely fast. The turbulence caused by the gas flow hitting the edge of the wafer may cause a reduction in the removal efficiency of contaminants, etc.In other words, by providing the interval L, these possibilities are reduced and the surface of the wafer is reduced. It is possible to easily form a gas flow that flows at a substantially uniform flow rate, and it is possible to perform a uniform and efficient contaminant removal operation on the front and back front regions of the wafer. Further, by adopting a configuration in which the clean gas is discharged in the vertical direction to the region which is directed to the angle β below the horizontal direction, the new clean gas comes into contact with the front and back of the wafer at a certain angle. As a result, contaminants and the like can be removed more efficiently. The interval L and the angle β remove the contaminants on the wafer 1 more efficiently and the pod 2 according to the size of the wafer held in the pod 2, each interval, the shape of the pod 2, and the like. It is preferable to adjust appropriately so that these can be discharged from the inside. For the same reason, the width, length, opening angle or number of the opening 22a may be increased or decreased from that of the embodiment, or the direction of the opening 22a may be changed.

  In the present invention, it is possible to remove contaminants and the like for each wafer and for the entire area of the front and back surfaces, and the state of cleanliness is higher than in the prior art. Thus, the wafer can be held inside the pod. Further, in the present invention, it is possible to individually control the gas flow rate, purge time, etc. required for the operation of removing contaminants and the like for each wafer. Therefore, it is possible to always perform the removal operation under a constant condition, and the management state of all the wafers in the pod can be easily kept constant.

  The gas supplied from the gas supply nozzle 21 into the pod 2 may be discharged using an exhaust hole provided in the pod 2 conventionally. In addition, since the purge operation is performed with the lid 4 opened, this may be performed using an exhaust system (not shown) provided in the transfer chamber. Also, it is considered preferable to prevent contaminants once removed from the wafer from reattaching to another wafer or the inside of the pod or flowing into the transfer chamber. In this case, as shown in [Patent Document 1], in order to efficiently exhaust the clean gas used for removing contaminants and the like, an exhaust-only small chamber communicating with the pod opening is provided in the transfer chamber. Also good.

  As described above, it is preferable that the contaminants once removed from the wafer are quickly carried out of the pod. For this reason, in order to more effectively remove contaminants, it is conceivable to add an exhaust port corresponding to each wafer as shown in [Patent Document 2]. However, the addition of such a configuration requires a significant standard change of the pod corresponding to the standard. Therefore, when the present invention is used for a system related to FOUP that is currently used, it is preferable that such an exhaust port is not provided.

  Further, it is conceivable that the contaminants adhere to the wafer in the form of dust, for example. It is considered that such dust is often charged and attached to the wafer by electrostatic attraction. Such dust can be removed more efficiently by spraying ionized gas rather than spraying a simple clean gas on the wafer. Therefore, it is more preferable that a so-called ionizer for ionizing gas or the like is added to the gas supply nozzle or in the vicinity thereof so that the ionized gas can be supplied as necessary.

  Next, the case where the purge apparatus according to the present invention is applied to a system related to FOUP currently used will be described below with reference to the drawings. Note that the semiconductor wafer processing apparatus and the pod to which the present invention is applied have substantially the same configuration as that described in the prior art, and thus description of the same configuration is omitted. The gas supply nozzle 21 described above may be supported and driven by a member independent of the door 6 described above. However, in this application example, the gas supply nozzle or the like according to the present invention is arranged on the upper portion of the door 6 to facilitate the implementation of the present invention.

  As for the schematic configuration of the wafer processing apparatus 50, as shown in FIG. 8 as a conventional technique, the transfer chamber 52 is provided with a transfer chamber opening 10 slightly larger than the lid 4 of the pod 2 on the load port portion 51 side. An opener 3 for opening and closing the lid 4 of the pod 2 is provided inside the transfer chamber 52 and on the side of the transfer chamber opening 10. Here, with reference to FIG. 3A and 3B, the opener 3 to which this invention is applied is demonstrated. 3A is a view showing the entire apparatus by reducing the load port portion 51, the pod 2, the opener 3 and the lid 4 in FIG. 1, and FIG. 3B is a view of the configuration shown in FIG. It is.

  The opener 3 includes a door 6 and a frame 5. The door 6 is a plate-like body having a size that closes the transfer chamber opening 10, and holding surfaces 11 a and 11 b that are vacuum suction holes are provided on the surface of the door 6. When the door 6 closes the transfer chamber opening 10, the surface located on the pod 2 side is a flat surface that can be in close contact with the lid 4. A fixing member 46 having a hole is attached to the door 6. A pivot 45 provided at the upper end of the door arm 42 is fixed in this hole by passing through it in a rotatable manner. A hole is formed in the lower end of the door arm 42. The pivot 40 passes through the hole and a hole at the tip of a rod 37 that is a part of an air-driven door opening / closing cylinder 31 that is a door opening / closing drive device. As a result, the door arm 42 is coupled to the cylinder 31 and is rotatably supported by the cylinder 31.

  The frame 5 is a structure made of a frame member arranged along the transfer chamber opening 10 and surrounding the door 6. The frame 5 is attached to the upper ends of the frame arm 12a and the frame arm 12b extending long in the lower frame member. A hole (not shown) is formed at the lower ends of the frame arm 12a and the frame arm 12b. A pivot 44 passes through the hole and a hole at the tip of a rod 38 that is a part of an air-driven frame driving cylinder 35 that is a frame driving device. As a result, the frame arm and the cylinder 35 are coupled, and the frame arm is rotatably supported by the cylinder 35.

  The frame arms 12a and 12b extend symmetrically and parallel to the vertical direction along the central axis of the frame 5 in order to support the load evenly. A rod 47 perpendicular to each of the frame arms 12a and 12b is attached between the upper and lower ends of each of the frame arms 12a and 12b. The support member 60 is provided with a fixing member 39 as a fulcrum support portion extending vertically from the support member 60. The fixing member 39 has a through hole parallel to the support member 60. A bearing (not shown) is disposed in the through hole of the fixing member 39, and the outer ring of the bearing pivots on the inner wall of the through hole and the inner ring of the bearing pivots the rod 47. Thus, the rod 47 constitutes the fulcrum 41 in a state of being enclosed in the through hole of the fixing member 39.

  The fulcrum 41 is configured as a coaxial fulcrum that serves as both the fulcrum of the arm frames 12a and 12b and the fulcrum of the door arm. That is, another through hole is provided between the upper end and the lower end of the door arm 42. A rod 47 passes through this through hole to form a fulcrum 41. The door arm 42 can be rotated around the fulcrum 41 by the expansion and contraction of the rod 37 driven by the cylinder 31. A fulcrum 41 of the door arm 42 is fixed to a support member 60 provided on a movable portion 56 capable of moving up and down. The door 6 has holding ports 11a and 11b, and can hold the lid 4 of the pod 2 by vacuum suction. The door arm 42 is disposed so as to be substantially vertical when the door 6 is pressed against the transfer chamber opening 10 (hereinafter referred to as a standby state), and the door 6 is moved to the transfer chamber 52 by rotating the door arm 42. Move away from the wall.

  The frame arms 12 a and 12 b can rotate around the fulcrum 41 in accordance with the expansion and contraction of the rod 38 driven by the frame driving cylinder 35. That is, the frame arms 12a and 12b are also fixed to a support member 60 provided on the movable portion 56 that can be moved up and down. The frame 5 is disposed so as to be obliquely separated from the wall surface of the transfer chamber 52 when the door 6 is in a standby state. That is, in this state, the frame arms 12a and 12b are supported in an inclined state so as to have an angle with respect to the door arm 42, and the upper portion of the frame 5 is separated from the wall surface of the transfer chamber 52 by a certain distance. ing. On the other hand, when the frame arms 12 a and 12 b are rotated in the direction in which the frame 5 contacts the wall surface of the transfer chamber 52 from this standby state, the frame 5 substantially contacts the wall surface of the transfer chamber 52.

  Support rods 13 a and 13 b are fixed to the frame member arranged at the upper part of the frame 5 so as to protrude toward the wall surface side of the transfer chamber 52. Transmission sensors 9a and 9b, which are first transmission sensors, are attached to the tips of the support bar 13a and the support bar 13b so as to face each other.

  The semiconductor wafer processing apparatus 50 is provided with a movable portion 56 for moving the opener 3 up and down. 4A is a view of the movable portion 56 of the opener 3 as viewed from the load port portion 51 side, and FIG. 4B is a view showing an arrow X in FIG. 4A. The movable portion 56 includes an air-driven rodless cylinder 33 and a support member 60 for moving up and down in the vertical direction, and is disposed below the lower surface of the pod 2 so as to be downstream of the air flow from the pod 2. Yes. A fixing member 39, an air driven cylinder 31 and a cylinder 35 are attached to the support member 60. The movable portion 56 is provided on the load port portion 51 side, and the opener 3 on the transfer chamber 52 side is supported by the door arm 42 and the frame arms 12 a and 12 b through the long hole 57 provided in the partition 55.

  The elongated hole 57 is provided with the moving direction of the movable portion 56, that is, in the case of the present embodiment, the vertical direction as the longitudinal direction. Further, the load port portion 51 and the transfer chamber 52 are partitioned by a cover 58 so that the cleanliness in the transfer chamber 52 is not lowered by the long hole 57. Further, a limiter 59 for preventing overrun when the opener 3 is lowered is provided below the partition 55. The partition 55 is provided with a rodless cylinder 33, a guide 61 a, and a guide 61 b along the elongated hole 57. The movable portion 56 moves up and down along the guide 61a and the guide 61b by the rodless cylinder 33. A sensor dog 7 is provided along the rodless cylinder 33 next to the movable portion 56.

  The sensor dog 7 is a plate-like body extending in a direction along the rodless cylinder 33, and has indicator means arranged at regular intervals in the longitudinal direction. In the present embodiment, as the indicator means, the concave and convex portions 12 which are notches arranged at regular intervals are provided. The number of projections and depressions corresponds to the number of wafer placement shelves in the pod, and the projections and depressions are arranged so that one notch always corresponds to any shelf with a movable part. A transmission sensor 8 as a second transmission sensor is fixed on the horizontal partition 55 in the movable portion 56 on the sensor dog 7 side.

  The sensor part of the transmission type sensor 8 is arranged so as to sandwich the irregularities 12 provided with the notches at a constant interval provided in the sensor dog 7, and the irregularities 12 of the sensor dog 7 according to the movement of the movable part 56. Can be detected. The support member 60 of the movable portion 56 is provided with a third transmission sensor 62, while the limiter 64 is provided in the partition 55 near the lower side of the long hole 57. In this mechanism, when the protruding portion shields the limiter 64, a stop signal is issued to the movable portion 56 and the entire operation of the opener 3 is stopped.

  Next, how the contaminant removal operation and the mapping operation on the wafer 1 are performed based on these configurations will be described with reference to FIGS. 3A and 3B to FIG. 7. 3A is a standby state, FIG. 5 is a state in which the frame 4 is operated by opening and closing the lid 4, FIG. 6 is a state in which the contaminant removal operation and the mapping operation in the wafer 1 are completed, and FIG. It is the figure which each showed the state where the flame | frame 5 returned to the standby state after completion of operation performed with respect to it. 4A and 4B respectively show a front view and a side view of a sensor dog provided for detecting the driving position of the frame 5 and related configurations.

  The shelves in the pod 2 that have completed the previous processing step contain the wafers 1 that satisfy the preprocessing standard, while the wafers 1 that do not satisfy the standard are excluded from the process at the preprocessing stage. Yes. The shelf in the pod 2 includes a stage where the wafer 1 is present and a stage where the wafer 1 is not present. The pod 2 in this state is placed on the base 53 on the transfer chamber 52 as shown in FIG. 3A and moves so as to be close to the transfer chamber opening 10. In this state, the opener 3 is in a standby state. That is, the rod 37 of the door opening / closing cylinder 31 is in the most extended state, and the door arm 42 is in a state of closing the door 6 against the transfer chamber opening 10 around the fulcrum 41.

  In this embodiment, in this state, the arm 42 is standing in the vertical direction. On the other hand, the rod 38 of the frame driving cylinder 35 is in the most contracted state, and the frame arms 12 a and 12 b are in a state of acting so as to separate the frame 5 from the wall surface of the transfer chamber 52 around the fulcrum 41. In other words, in this embodiment, the frame arms 12a and 12b are inclined with respect to the door arm 42 at a certain angle.

  FIG. 5 shows a state where the pod 2 is close to the transfer chamber opening 10 and the door 6 holds the lid 4. When the pod 2 is close to the transfer chamber opening 10, the lid 4 of the pod 2 comes into close contact with the door 6 and holds the lid 4 of the pod 2 through the holding portions 11 a and 11 b by vacuum suction. When the door 6 holds the lid 4, the door opening / closing cylinder 31 works to contract the rod 37. Subsequently, the pivot 40 provided at the end of the door arm 42 is drawn toward the support base 60 side, and the door arm 42 is rotated by the fulcrum 41 so as to pull the door 6 away from the transfer chamber opening 10 according to the principle of scissors. The lid 4 is opened from the pod 2.

  After the lid 4 is opened, the movable portion 56 is slightly lowered to a position where the upper end of the frame 5 enters the position of the opening 10 and the frame arms 12a and 12b can rotate. After the end of the descent, the frame arm 12 actually starts its pivoting operation. That is, the frame arms 12 a and 12 b rotate until the rod 38 of the frame driving cylinder 35 extends and the frame 5 substantially contacts the periphery of the transfer chamber opening 10. Then, the transmissive sensors 9 a and 9 b attached to the upper side of the frame 5 go out from the transfer chamber opening 10 and are inserted into the pod 2. At this point, the gas supply nozzle 21 is positioned in the arrangement shown in FIG. 1A. The first transmission sensors 9a and 9b are arranged so that the wafer 1 exists on a straight line connecting them, and constitute a detection space.

  In this state, the movable portion 56 moves in the vertical direction, and simultaneously, the contaminant removal operation and the wafer 1 mapping operation by spraying highly clean gas on each wafer 1 are sequentially executed. That is, the opener 3 is lowered to the position shown in FIG. 6 by the rodless cylinder 33. The transmissive sensors 9 a and 9 b are moved downward along with the movable portion 56 and the opener 3 in the direction perpendicular to the surface of the wafer 1. When the wafer 1 is on the shelf level, the light emitted from the transmission sensor 9a is blocked. On the other hand, when the wafer 1 is missing from the shelf level, the light of the transmission sensor 9a is not blocked. Each sensor is set so that a non-transmission signal is emitted when the transmission sensor 9b is blocked by the wafer 1, and a transmission signal is generated when the transmission sensor 9b is not blocked by the wafer 1.

  Accordingly, it can be determined that the wafer 1 exists when the non-transmission signal is detected, and it can be determined that the wafer 1 is missing when the transmission signal is detected. In response to this transmission signal, clean gas is sprayed from the gas supply nozzle 21 to the wafer 1 at a predetermined pressure for a predetermined time, thereby effectively removing contaminants and the like from individual wafers. Can be done. In this case, in consideration of gas use efficiency, the blowing of highly clean gas may be stopped in accordance with the non-permeation signal. In consideration of the change, the gas blowing conditions may be changed.

  The sensor part of the transmission type sensor 8 is arranged so as to sandwich the irregularities 12 provided with the notches at a constant interval provided in the sensor dog 7. Accordingly, when the movable portion 56 is lowered, the transmission sensor 8 is also lowered to detect the unevenness 12 of the sensor dog 7. At this time, when the transmission sensor 8 passes through the concave portion, the transmission sensor 8 emits a transmission signal without being shielded from light, and when it passes through the convex portion, the transmission sensor 8 is shielded from light and emits a non-transmission signal. Yes. Therefore, the unevenness 12 of the sensor dog 7 can be set in advance so that the time when the transmission sensors 9a and 9b pass through each step of the shelf in the pod 2 corresponds to the time when the transmission sensor 8 passes through the recess. For example, the transmission / non-transmission signal detected by the transmission / transmission sensor 8 indicates the signal of the shelf stage through which the transmission sensor 9 actually passes.

  Compared with the detection result of the transmission / non-transmission signal detected as a result of the light shielding of the wafer 1 by the transmission sensor 9a, the transmission sensor 8 detects the signal corresponding to the shelf level. If 9a is shielded from light, it can be determined that the wafer 1 is present on the shelf. On the other hand, if the transmission sensor 9a is not shielded, it can be determined that the wafer 1 is missing from the shelf. Based on these determinations, it is possible to perform the removal operation of contaminants and the like more effectively by changing the spraying timing or spraying conditions of the highly clean gas. This is repeated for all the wafers 1, and the support rod reaches the mapping end position of the opener 3, whereby the contaminant removal operation and the mapping operation are completed.

  Thereafter, when the rod 38 of the frame opening / closing cylinder 35 is contracted again, the frame arms 12 a and 12 b are rotated, and the frame 5 moves away from the transfer chamber opening 10. When the rod 38 is most contracted, the movement of the frame 5 is completed. Then, the movable portion 56 moves to the lowest point, and the series of operations for removing and mapping contaminants and the like on the wafer 1 is completed as the lid 4 is opened. This state is the state shown in FIG.

  As described above, in this embodiment, the gas supply nozzle 21 is fixed to the door 6 that moves in parallel with the direction in which the wafers are stacked. Accordingly, it is possible to always supply clean gas to each wafer under the same conditions. Further, by using the sensor dog 7 and the transmission sensor 8, a synchronization signal corresponding to the shelf level in the pod 2 can be easily generated, so that the wafer can be used without using a drive motor as a driving device. Simultaneously with the mapping operation 1, it is possible to perform a more effective operation for removing contaminants and the like.

  In the present embodiment, the fulcrum of the door arm 42 and the fulcrum of the mapping frame 5 are shared by the fulcrum 41, but the same effect can be achieved by using both as a separate fulcrum. That is, even if different fulcrums are provided as the first fulcrum provided on the door arm 42 and the second fulcrum provided on the mapping frame, the same effect can be obtained. Although the movable part 56 is integrated with the fulcrum 41, the door opening / closing cylinder 31 and the mapping frame driving cylinder 35, they are not necessarily integrated to obtain the effects of the present invention. As long as these mechanisms are arranged downstream of the air flow with respect to the pod 2, the same effect is obtained.

  In this embodiment, the gas supply nozzle is fixed to the upper portion of the door for the purpose of applying the present invention without making a major change to the configuration conforming to the FOUP standard. However, the present invention is not limited to this. Specifically, the gas supply nozzle may be configured such that the door forms a different frame and is fixed on the frame. Further, a drive mechanism may be added to the gas supply nozzle so that the gas supply nozzle can be rotated with respect to an axis parallel to the wafer surface. It is also conceivable that the state of adhesion of contaminants varies depending on the treatment performed immediately before. In this case, the width, length, opening angle, or number of openings in the gas supply nozzle may be increased or decreased in view of the adhesion state and the gas usage state. In this case, the increase in number refers to both an increase in the number of openings in the horizontal direction and an increase in the number of openings in the vertical direction.

  In this embodiment, the contaminant removal operation is performed only once in accordance with the mapping operation, but the present invention is not limited to this. The removal operation can be always performed except when the robot arm in the transfer chamber is accessing the wafer in the pod. Therefore, the removal operation may be repeatedly performed on the wafer held in the pod while the wafer is subjected to various processes in the processing apparatus.

  In the present embodiment, the FOUP is described as an object, but the application example of the present invention is not limited to the system. As long as the system has a container for storing a plurality of objects to be held therein and a transfer chamber for transferring the objects to be held from the container to a device for processing the objects to be held, the contaminants and the like according to the present invention It is possible to apply a removal device (purge device).

It is a figure which shows schematic structure at the time of seeing these from the side regarding the purge apparatus which concerns on one embodiment of this invention, a pod, the lid | cover for pods, and a part of opener. It is a figure which shows schematic structure at the time of seeing these from the side regarding the purge apparatus which concerns on one embodiment of this invention, a pod, the lid | cover for pods, and a part of opener. It is a figure which shows schematic structure at the time of seeing this from the side regarding the principal part of the purge apparatus which concerns on one embodiment of this invention. It is a figure which shows schematic structure of the state which looked at the purge apparatus which concerns on one embodiment of this invention, and the structure arrange | positioned around from the upper direction. It is a figure which shows schematic structure at the time of cut | disconnecting this horizontally and seeing the said cut surface from upper direction regarding the principal part of the purge apparatus which concerns on one embodiment of this invention. (A) It is a figure which shows the schematic structure of the state which reduced the structure of the opener shown in FIG. 1, and its vicinity, and this was seen from the side surface. (B) It is a figure which shows schematic structure at the time of seeing the structure shown to FIG. 3 (A) from the conveyance chamber side. (A) It is the front view which looked at the said movable part from the load port side regarding the movable part of the opener in the Example of this invention. (B) It is a figure which shows the state which looked at the structure shown by FIG. 3 (A) from the side surface. It is a figure which shows the schematic structure of the state which looked at the opener etc. which looked at the mapping process of a wafer from the side, Comprising: It is the figure which showed the state when the mapping preparation was completed. It is a figure which shows the schematic structure of the state which looked at the opener etc. which looked at the mapping process of a wafer from the side, Comprising: It is the figure which showed the state when mapping operation was completed. It is a figure which shows the schematic structure of the state which looked at the opener etc. which looked at the mapping process of a wafer from the side surface, Comprising: It is the figure which showed the state when all the mapping and the open | release operations of a cover were completed. It is a whole side view which shows schematic structure of the general semiconductor wafer processing apparatus with which this invention and a prior art are applied. (A) It is a figure which expands the structure of the conventional opener in the apparatus shown in FIG. 8, and its vicinity, and shows schematic structure of the state which looked at this from the side surface. (B) It is a figure which shows schematic structure at the time of seeing the structure shown to FIG. 9 (A) from the conveyance chamber side. It is a figure which shows schematic structure of the state which looked at the opener etc. which looked at the purge operation of a wafer from the side, Comprising: It is the figure which showed the state when purge preparation was completed.

Explanation of symbols

1: Wafer 2: Pod 3: Opener 4: Cover 5: Frame 6: Door 7: Sensor Dog 9: Transmission Sensor 10: Transfer Chamber Opening 21: Gas Supply Nozzle 50: Semiconductor Processing Device 51: Load Port 52: Transfer Chamber

Claims (10)

The to-be-accommodated housed in a pod comprising an opening and a main body composed of a plurality of shelves arranged in a predetermined direction on which the to-be-contained objects are respectively placed, and a lid that is separable from the main body and closes the opening A purging device that performs a purging operation by blowing a predetermined gas on an object,
The predetermined gas is sprayed substantially uniformly on substantially the entire area of the surface of the object that is spaced a predetermined distance from the end of the object and extends perpendicularly to the predetermined direction. A gas supply nozzle;
A purge apparatus comprising: a support member that supports the gas supply nozzle and is capable of driving the gas supply nozzle in the predetermined direction.   The purge apparatus according to claim 1, wherein the support member is a member that attaches and detaches the lid from the main body of the pod.   The timing at which the predetermined gas is blown out from the gas supply nozzle is synchronized with the timing at which the object to be passed passes through the extending plane when the support member moves in the predetermined direction. The purge apparatus according to claim 1.   The gas supply nozzle blows out the predetermined gas to a region surrounded by a plane parallel to a plane in which the object is extended and a plane extending downward at a predetermined angle with respect to the plane. The purge apparatus according to claim 1.   The object to be accommodated is a wafer used for semiconductor manufacturing, and the lid is separated from the main body when the pod is placed on a load port and the wafer accommodated in the pod is loaded. 2. The purge apparatus according to claim 1, wherein the purge apparatus is in a state of being transferred to a wafer processing apparatus via a port. The to-be-accommodated housed in a pod comprising an opening and a main body composed of a plurality of shelves arranged in a predetermined direction on which the to-be-contained objects are respectively placed, and a lid that is separable from the main body and closes the opening A purging method for performing a purging operation by blowing a predetermined gas on an object,
Separating the lid from the body;
Holding the state where the front surface of the opening is spaced a predetermined distance from the end of the object, and moving the gas supply nozzle along the predetermined direction;
Purging the containment object by spraying the prescribed gas substantially uniformly onto substantially the entire area of the surface of the containment object extending in a direction perpendicular to the prescribed direction from the gas supply nozzle. A purging method comprising the step of:   The purging method according to claim 6, wherein the gas supply nozzle is fixed to a door used to remove the lid from the main body of the pod.   7. The purging step is performed in synchronism with a timing of passing the object to be accommodated when the gas supply nozzle moves in the predetermined direction. Purge method.   In the purging step, the gas supply nozzle has the predetermined gap between a plane parallel to a plane in which the object is extended and a plane extending downward at a predetermined angle with respect to the plane. The purge method according to claim 6, wherein the gas is blown out. The object to be accommodated is a wafer used for semiconductor manufacturing, and the lid is separated from the main body when the pod is placed on a load port and the wafer accommodated in the pod is loaded to the load. The purge method according to claim 6, wherein the purge method is in a state of being transferred to a wafer processing apparatus via a port.

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