Abstract:
The present invention relates to a FOUP loading apparatus capable of implementing a stable horizontal and locking state when a FOUP is loaded and transferred by implementing a stable locking state of a locker on a stage of a FOUP opener and preventing ant interference when the FOUP is positioned. The FOUP loading apparatus for a FOUP opener includes a stage moved on a support base frame, a stage driving unit for forwardly and backwardly moving the stage along a set way, a locker locked on the stage for engaging the FOUP, and a locker driving unit for driving the locker. In the FOUP loading apparatus, a stable locking operation is implemented on a stage, and a stable positioning operation of the FOUP is obtained, so that it is possible to implement a stable FOUP positioning and loading operation from the positioning process to the transferring process.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a FOUP loading apparatus for a FOUP opener(which is a kind of a wafer loading container for loading a large diameter wafer), and in particular to a FOUP loading apparatus for a FOUP opener which is capable of implementing a stable loading operation of a stage and a locker and an accurate horizontal state of a FOUP support base.  
           [0003]    2. Description of the Background Art  
           [0004]    Generally, a wafer is an important material for fabricating a semiconductor. Therefore, a wafer loading operation needs a certain cleanness and stability. When a wafer is loaded, the wafer is received in a FOUP and is loaded to a working place in a sealed state. The locked state of the FOUP is unlocked using a FOUP opener and is transferred to a working place(cleaned equipment). The conventional FOUP opener will be explained with reference to FIG. 1.  
           [0005]    [0005]FIG. 1 is a perspective view illustrating the schematic structures of a conventional FOUP opener and FOUP.  
           [0006]    As shown therein, a FOUP opener  100  is installed at an entrance of a clean room for a wafer process. A support base frame  120  is installed at the entrance in a horizontal direction, and a vertical frame  110  is formed thereat in a vertical direction. A door holder  130  is installed at the side of the vertical frame  110  of the FOUP opener, and the door holder  130  is installed in a frame  112  which is upwardly and downwardly moved in the back side of the vertical frame. The door holder  130  includes an adjusting pin  150  and a latch key  140  which are operable based on the opening state of the FOUP.  
           [0007]    As shown in FIG. 1, the FOUP  200  engaged to the FOUP opener  100  is separated into a body and a door  210 . An adjusting pin hole  230  and a latch key hole  220  are formed in the door  210 . The door  210  is unlocked by the adjusting pin  150  and the latch key  140  of the door holder  130 . The unlocked door  210  is moved to the back of the FOUP opener  100  by the door holder  130  for thereby opening the FOUP  200 . The wafers are unloaded from the interior of the opened FOUP by a certain unloading member such as a robot arm, and the door  210  is returned to the original position by the door holder  130  and is locked. The locked FOUP  200 , is moved to the original position by a certain transfer member.  
           [0008]    The conventional FOUP opener has some problems when the FOUP is positioned on the stage.  
           [0009]    First, the FOUP positioned on the stage is fixed by a locker or fixed on the stage when the stage movement is ended. There are various locking methods for fixing the FOUP on the stage. For example, a T-shaped section locker integrally installed on the stage and a 90° angled type locker installed on the support base frame, not on the stage, are known.  
           [0010]    In the earlier case, the locker fixes the lower surface of the FOUP which is rotated on the stage at a certain angle and is placed, and in the later case, the FOUP is automatically engaged by the stage which is forwardly moved.  
           [0011]    In the above-described locker type, it is impossible to separate the positioning FOUP in the upper direction but it is easier to separate by backwardly pulling the same. In addition, the FOUP is positioned by simply engaging the same, so that it is impossible to implement a stable engagement. The FOUP is downwardly moved by a transferring system capable of transferring the FOUP along a ceiling rail. In this case, if the positioning area is expanded, the FOUP may be collided with a protruded locker at the moment when the FOUP positioned.  
           [0012]    Second, if the positioning of the FOUP is inaccurate, when the FOUP door is unlocked, a connection error occurs. Therefore, there is a big problem in that the process is continuously performed.  
           [0013]    The positioning error may be detected by a certain detection unit. However, it is impossible to judge whether the positioned state is obtained in the horizontal state. It is possible to prevent a unloading error which occurs due to a difference with another apparatus which maintains an accurate horizontal in a process for opening a door of a FOUP or unloading the wafer from the opened FOUP by judging a horizontal state when the FOUP is positioned. In addition, it is possible to prevent a wafer damage which occurs when there is an unbalance with respect to the wafer by judging the horizontal state.  
           [0014]    Therefore, when the FOUP is transferred through the automatic transfer system and is positioned on the support base frame, the locker must equip the following conditions.  
           [0015]    When the locker is installed on the stage, the locker must be installed in a portion which is not higher than the height of a surface of the stage. The locking state on the lower surface of the FOUP must be stable. When the FOUP is positioned on the stage of the support base frame, the FOUP must be positioned on the stage without any collision, and an accurate horizontal state must be implemented.  
         SUMMARY OF THE INVENTION  
         [0016]    Accordingly, it is an object of the present invention to provide a FOUP loading apparatus for a FOUP opener which overcomes the problems encountered in the conventional art.  
           [0017]    It is another object of the present invention to provide a FOUP loading apparatus for a FOUP opener which is capable of implementing a horizontal state of a stage by providing a horizontal state maintaining member and a support state that the FOUP is not separated upwardly or backwardly and is not movable.  
           [0018]    In order to achieve the above objects, there is provided a FOUP loading apparatus for a FOUP opener which includes a stage moved on the support base frame, a driving unit for forwardly and backwardly moving the stage along a certain set way, and a locking unit installed in the stage for engaging the FOUP.  
           [0019]    The locking unit further includes a driving unit which is independently operated on a lower surface of the stage and is formed of an upper engaging shoulder portion inserted under the lower surface of the FOUP, a shaft portion which forms a rotation center, and a lower operation bar moved by the driving unit.  
           [0020]    In the FOUP loading apparatus according to the present invention, a lower driving plate is movably installed between the support base frame and the stage and is integrally connected with the stage. The stage is connected with the connection member in an opening of the support base frame. The connection member is connected with the lower driving plate. The lower driving plate is connected with a moving member which is moved along the fixing member fixed to a lower surface of the support base frame. The lower driving plate is movably connected with the front end of the rod of the driving unit. The stage includes more than one sensor for detecting the loading state of the FOUP on the stage, and a sensor for detecting whether the FOUP is loaded on the stage. A magnetic sensor is further provided for detecting the front and rear positions of the moved stage.  
           [0021]    In another embodiment of the present invention, there is provided a FOUP loading apparatus for a FOUP opener which includes a support base frame having a concave portion, a support plate received in the concave portion of the support base frame and including a guide rail at upper both sides, a loading screw parallel with the guide rail and a stage driving motor for driving the loading screw, a stage including a guide member engaged with the guide rail of the support plate and a nut engaged with the loading screw on the lower surface of the same, and a locking unit including a locker inserted into a lower portion of the stage, protruded from the upper portion of the same and having a worm wheel in a lower portion for being fixed to the stage, a worm engaged with the worm wheel of the locker and a locker driving motor connected with the worm and generating a driving force. The stage includes more than one sensor for detecting the loading state of the FOUP on the stage, and a sensor for detecting whether the FOUP is loaded on the stage. In addition, there are further provided three pairs of fixing screws and level adjusting pins for maintaining a horizontal state of the stage of the FOUP loading apparatus according to the present invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein;  
         [0023]    [0023]FIG. 1 is a perspective view illustrating a schematic structure of a conventional FOUP opener;  
         [0024]    [0024]FIG. 2 is a disassembled view illustrating a support base frame of a FOUP loading apparatus of a FOUP opener and a stage according to the present invention;  
         [0025]    [0025]FIG. 3 is a cross sectional view illustrating an engaged state of a support base frame of a FOUP loading apparatus and a stage according to the present invention;  
         [0026]    [0026]FIG. 4 is an enlarged cross-sectional view illustrating a locker installation structure of a FOUP loading apparatus according to the present invention;  
         [0027]    [0027]FIG. 5 is a bottom view illustrating a support base frame of a FOUP loading apparatus according to the present invention;  
         [0028]    [0028]FIG. 6 is an enlarged cross-sectional view illustrating a horizontally engaged state of a stage and a lower driving plate of a FOUP loading apparatus according to the present invention;  
         [0029]    [0029]FIG. 7 is a view illustrating a LM guide according to the present invention;  
         [0030]    [0030]FIG. 8 is a plan view illustrating another embodiment of a FOUP loading apparatus according to the present invention;  
         [0031]    [0031]FIG. 9 is a cross-sectional view illustrating another embodiment of a FOUP loading apparatus according to the present invention;  
         [0032]    [0032]FIG. 10 is a cross-sectional view taken along line A-A of FIG. 8 according to the present invention;  
         [0033]    [0033]FIG. 11 is a cross-sectional view taken along line B-B of FIG. 8 according to the present invention;  
         [0034]    [0034]FIG. 12 is a cross-sectional view illustrating a locker which fixes a FOUP by cutting the same in a lateral direction in FIG. 8 according to the present invention; and  
         [0035]    [0035]FIG. 13 is a cross-sectional view taken along line C-C of FIG. 12 according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0036]    The present invention will be explained with reference to the accompanying drawings.  
         [0037]    [0037]FIGS. 2 through 7 are view illustrating a FOUP loading apparatus of a FOUP opener according to the present invention which uses a pneumatic cylinder as a driving unit of a stage and a locker.  
         [0038]    [0038]FIG. 2 is a disassembled perspective view of a support base frame and a stage of a FOUP loading apparatus of a FOUP opener according to the present invention. As shown therein, the support base frame  102  capable of moving the stage  400  thereon is separated. A lower driving plate  220  is positioned on the lower surface of the support base frame  102 , and the lower driving plate  220  is integrally connected with the stage  400  through an opening  120 .  
         [0039]    As shown in FIG. 2, the stage  400  is fabricated in a certain shape plate member, and a concave portion is formed in the center of the end portion of the stage  400 , and a locker  700  is installed in the concave portion. The locker  700  will be explained later.  
         [0040]    On the upper portion of the stage, there are three positioning pins  408 , and a FOUP loading state detection sensor  500  for detecting a loading state of the FOUP, and normal position sensors  502  for detecting the FOUP positioning state.  
         [0041]    [0041]FIG. 3 is a cross-sectional view illustrating an engaging state of the support base frame and stage of the FOUP loading apparatus according to the present invention.  
         [0042]    The stage driving unit  620  according to the present invention is installed at a portion distanced from the lower driving plate  220  on the lower surface of the support base frame  102 . The stage driving unit  620  is formed of a pneumatic cylinder and includes a rod  622  which is moved through the front portion. The front end of the rod  622  is connected with the lower driving plate  220  for thereby moving the lower driving plate  220  using the stage driving unit  620 . The front end of the rod  622  is connected with the lower driving plate  220  using a bolt  626 .  
         [0043]    In the stage, a support base frame  102  is positioned in the lower portion, and the lower driving plate  220  is movably positioned at the side of the opening of the support base frame  102 .  
         [0044]    Since the lower driving plate  220  is connected with the stage  400  on the support base frame  102  through the opening  120  formed in the support base frame  102 , the stage  400  is positioned above the support base frame  102  by the lower driving plate  220 . Therefore, when the lower driving plate  220  is moved by the stage driving unit  620 , the stage  400  is moved.  
         [0045]    The locker  700  is positioned in the front surface of the stage  400 . The locker  700  is rotatably installed in an end groove portion of the stage  400 . The movement distance of the stage  400  is detected by a magnetic sensor  624  attached in the stage driving unit  620 .  
         [0046]    [0046]FIG. 4 is an enlarged cross-sectional view illustrating a locker installation structure of the FOUP loading apparatus according to the present invention.  
         [0047]    The locker  700  capable of maintaining a horizontal state of the FOUP on the stage  400  is rotatably installed in a portion of the groove of the stage  400 . The locker  700  includes an angled upper engaging shoulder portion  702  inserted into the lower surface of the FOUP, a shaft  824  which forms a rotation center, and a slanted lower operation bar  826  moved by the driving unit.  
         [0048]    The operation bar  826  is connected with a rod  822  of the locker driving unit  820  which is independently operated on the lower surface of the stage  400 . The locker driving unit  820  is a pneumatic cylinder having a fixed end portion and connects the front end of the rod  822  with the operation bar  826  of the locker.  
         [0049]    Therefore, the locker  700  is rotated based on a pneumatic operation of the locker driving unit  820  and is inserted into the lower portion of the stage and engages the lower surface of the FOUP. The front end of the engaging shoulder portion  702  is formed in a flexible slidable sphere shape.  
         [0050]    [0050]FIG. 5 is a bottom view illustrating the support base frame of the FOUP loading apparatus according to the present invention.  
         [0051]    [0051]FIG. 5 illustrates the installation structures of the stage driving unit  620  on the lower surface of the support base frame  102  which forms the opening  120 .  
         [0052]    A hole is formed on the front end of the rod  622  of the stage driving unit  620  for passing through the bolt  626 .  
         [0053]    The lower driving plate  220  includes a connection member on the upper surface and includes three pairs of level adjusting pins  202  and fixing screws  204  for maintaining a horizontal state of the stage. The horizontal state implemented using the level adjusting pins  202  and the fixing screws  204  will be explained later.  
         [0054]    Two portions of the stage  400  and the lower driving plate  220  are connected using the connection member  224 , and the remaining one portion is connected with the level adjusting pins  202  and the fixing screws  204  from the lower driving plate  220  and the stage  400  through the opening  120 . The level adjusting pins  202  and the fixing screws  204  are connected with the connection member.  
         [0055]    [0055]FIG. 6 is an enlarged cross-sectional view illustrating a horizontal engaged relationship of the stage and lower driving plate of the FOUP loading apparatus according to the present invention.  
         [0056]    A pair of the level adjusting pin  202  and the fixing screw  204  are installed for maintaining a horizontal state of the stage  400  connected with the lower driving plate  220  which is moved in the lower portion of the support base frame  102 . Namely, the, horizontal state of the stage  400  is roughly adjusted using the level adjusting pin  202 , and the fixing screw  204  is sequentially fixed for thereby implementing a horizontal state of the stage.  
         [0057]    [0057]FIG. 7 is a view illustrating the LM guide according to the present invention.  
         [0058]    The LM guide is formed of a fixing member  222  and a moving member  224 . The fixing member  222  is fixed on the upper surface of the support base frame  102 , and the moving member  224  is attached to the lower surface of the lower driving plate  220 . The moving member  224  is formed of a plurality of ball bearings.  
         [0059]    [0059]FIGS. 8 through 13 are views of another embodiment of the FOUP loading apparatus of the FOUP opener according to the present invention which uses driving motors as a driving unit of the stage and the locker.  
         [0060]    [0060]FIGS. 8 and 9 are plan and cross-sectional views of another embodiment of the FOUP loading apparatus of the FOUP opener according to the present invention.  
         [0061]    As shown therein, the center portion of the support base frame  102  is grooved, and the support plate  200  is inserted into the groove. The height of the support plate  200  is adjustable. The above-described construction will be explained with reference to FIGS. 10 and 11. A guide rail  300  is installed at both sides of the support plate  200 . A guide member  302  is installed at both sides of the stage  400 , so that the stage is moved along the guide rail  300 . The guide member  302  includes an inverted U-shaped positioning groove  304  positioned in the guide rail  300  and is fixed to the stage  400  based on a fixing bracket  402 . Normal position detection sensors  502  are installed in both front sides and rear center portion of the stage distanced from the guide member  302  by a certain distance for detecting whether the FOUP is accurately positioned. A loading state detection sensor  500  is installed in the center portion of the stage for detecting whether the FOUP is loaded.  
         [0062]    A stage driving motor  600  is fixed to an upper portion of the support plate  200 , and a loading screw  604  is coupled to the shaft  602  of the stage driving motor  600 . The loading screw  604  is installed parallely with respect to the guide rail  300 , and one end of the same is fixed to the support plate  200  using a loading screw support bracket  608  based on the bearing  606  for implementing a smooth movement. A nut  404  is engaged with the lower portion of the stage  400 . Therefore, the nut  404  is linearly moved based on the rotation of the loading screw  604  and linearly moves the stage  400  fixed to the nut  404 . The moving direction of the nut  404  is changed based on the change of the rotation direction of the loading screw  604 , so that the stage  400  is reciprocated.  
         [0063]    [0063]FIG. 10 is a cross-sectional view taken along line A-A of FIG. 8 for explaining a centering method of the support plate, and FIG. 11 is a cross-sectional view taken along line B-B for explaining the height adjusting unit of the stage.  
         [0064]    As shown in FIG. 10, the support base frame  102  is fixed to the main frame  100 . The centering operation is implemented using the center adjusting pin  106 . In order to adjust the level of the stage  400 , the level adjusting pin  202  is vertically engaged to the lower plate portion of the groove of the support base frame  102  for adjusting the level of the stage  400  as shown in FIG. 11, so that the support plate  200  is supported by the end portion of the same. The level adjusting pin  202  is rotated below the support base frame  102  for thereby adjusting the height of the same, and the fixing screw  204  is engaged into the screw hole  206  of the support plate  200  for thereby fixing the adjusted height. Three level adjusting pins  202  are installed. Namely, as shown in FIG. 8, one is installed in the front portion of the stage  400 , and the remaining two are installed in rear portions. The horizontal height of the stage is adjusted by adjusting the level adjusting pin of the front portion. Therefore, it is possible to easily arrange the heights of the latch key hole of the FOUP and the latch key of the door holder by adjusting only one level adjusting pin positioned in the front portion. After the level of the front portion of the FOUP is adjusted, the horizontal height of the FOUP is adjusted by adjusting two level adjusting pins in the rear portion.  
         [0065]    [0065]FIG. 12 is a cross-sectional view obtained by cutting a lateral side of the locker portion which fixes the FOUP of FIG. 8, and FIG. 13 is a cross-sectional view taken along line C-C of FIG. 12.  
         [0066]    The locker  700  is fixed to a lower portion of the stage  400 , and the upper portion of the same is exposed to the locker unloading port of the stage  400 . The upper engaging portion  702  of the locker  700  is inserted into a locking hole of the lower surface of the FOUP(not shown) for thereby fixing the FOUP on the stage  400 . The locker  700  is fixed to a lower portion of the stage  400  using the locker bracket  704 , and a worm wheel  706  is formed in a lower portion of the body of the locker  700 . The worm wheel  706  is engaged with a worm  800  positioned in the lower portion. The worm  800  is supported by the bearings  802  fixed to the locker bracket  704 , and one end of the same is connected with the shaft  808  of the locker driving motor  806 . Therefore, when the locker driving motor  806  is rotated, the work  800  is rotated by receiving the driving force of the locker driving motor  806 , and as the worm  800  is rotated, the worm wheel  706  connected with the worm  800  is rotated, and the locker  700  is rotated at a certain rotation angle. The engaging shoulder portion  702  of the upper portion of the same is rotated in the forward direction about the shaft in the locker  700  and is inserted into the locking hole of the FOUP for thereby fixing the FOUP on the stage  400 . The apparatus according to the present invention is implemented by the worm  800  rotated by the locker driving motor  806  as a driving force source of the locker  700  and a worn wheel  706  which is rotated based on an engagement with the worm  800 .  
         [0067]    The operation of the present invention will be explained with reference to the accompanying drawings.  
         [0068]    In the present invention, when a worker places a FOUP on the stage, the operation is started. When the FOUP is placed on the upper surface of the stage, the position of the FOUP is determined based on three positioning pins. Thereafter, the FOUP loading state detection sensor detects the loading state of the FOUP, and the normal position detection sensors detect whether the FOUP is normally positioned and compares with a reference value. If unbalanced, a certain operation mode is stopped or an alarming signal is outputted.  
         [0069]    When the FOUP is normally positioned, the rod of the locker driving unit moves the locker lower operation bar, and the locker having the moved lower portion is rotated with respect to the shaft portion and engages a certain portion of the lower surface of the FOUP on which the upper engaging shoulder portion is positioned. The FOUP positioned on the stage is stably engaged by the locker for thereby maintaining a positioned state.  
         [0070]    The stage is forwardly moved by a certain distance by driving the stage driving unit. The FOUP positioned on the stage based on the movement of the stage is moved to the side of the door holder of the FOUP opener, and the movement of the stage is stopped by the magnetic sensor attached to the driving unit, and the door opening operation of the FOUP is performed.  
         [0071]    In the present invention, the problems that the stage is fixed by only the fixing screws are overcome using a pair of fixing units formed of level adjusting pins and fixing screws capable of adjusting the horizontal state of the stage.  
         [0072]    In addition, the horizontal state of the stage and the support base frame is implemented, and in a state that the FOUP is positioned, the horizontal state is detected for thereby readjusting the level of the stage for thereby preventing a damage of the wafer when unloading the same.  
         [0073]    In particular, an engaging shoulder portion of the rotation engagement is implemented so that the FOUP on the stage is not moved in the upper or rear ward direction for thereby implementing a stable support state.  
         [0074]    In the FOUP loading apparatus of the FOUP opener, even when the locker is installed on the stage, it is installed at a height lower than the stage, and since the positioning area of the FOUP is wide on the stage of the support base frame, it is possible to prevent any interference of the FOUP due to a locker.  
         [0075]    As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.