Abstract:
An apparatus for a liquid crystal display device includes: a process chamber for treating a substrate; a load-lock chamber having an interior conveyor; and a transfer chamber connected to the process chamber and the at least one load-lock chamber, the transfer chamber having a substrate-transferring means.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present invention claims the benefit of Korean Patent Applications No. 2003-0068347 filed in Korea on Oct. 1, 2003 and No. 2004-0077541 filed in Korea on Sep. 25, 2004, which are hereby incorporated by references. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to an apparatus for a liquid crystal display device, and more particularly, to an apparatus where large-sized substrates are exchanged in a load lock chamber having a conveyor. 
     DISCUSSION OF THE RELATED ART 
     In general, a liquid crystal display (LCD) device is fabricated by repeating a deposition step of a thin film on a substrate, a photolithographic step using a photoresist, a selective etch step of the thin film and a cleaning step of the substrate. These steps for a fabrication process of an LCD device may be performed using an apparatus having a process chamber under an optimum condition. Recently, a cluster including process chambers for treating substrates, a transfer chamber for moving the substrates into and out of the process chambers and a load-lock chamber connected to the transfer chamber for storing the substrates temporarily has been widely used as an apparatus for fabricating an LCD device because of its superior treatment capability of large number of substrates in a short time period. The cluster may be used as a plasma enhanced chemical vapor deposition (PECVD) apparatus or a dry etch apparatus. 
       FIG. 1  is a schematic view showing a cluster according to the related art. In  FIG. 1 , a cluster includes a load-lock chamber  20 , a transfer chamber  50  and a plurality of process chambers  30 . The cluster further includes a pre-heating chamber  40  for heating a substrate  60  before a treatment in the plurality of process chambers  30  and the load-lock chamber  20  is connected to a storing unit  10  where a plurality of substrates  60  are stored. The transfer chamber  50  includes a transfer chamber robot  52  transferring the substrate  60  among the load-lock chamber  20 , the process chambers  30  and the pre-heating chamber  40  and the storing unit  10  includes a storing unit robot  12  transferring the substrates  60  to and from the load-lock chamber  20 . The transfer chamber robot  52  and the storing unit robot  12  are operated using rotation and linear movement of an arm or using horizontal reciprocation of a conveyor. The pre-heating chamber  40  may be omitted according to the process requirement. In addition, the number of the pre-heating chambers and the load-lock chambers may vary as the process. 
       FIG. 2  is a schematic cross-sectional view of a load-lock chamber for a cluster according to related art. In  FIG. 2 , a load-lock chamber  20  includes first and second plates  26  and  28  therein for exchanging substrates  60 .  FIG. 2  shows a state when a substrate  60  is loaded on the first plate  26  and the second plate  28  under the first plate  26  is vacant. After a substrate is treated in the process chamber  30  (of  FIG. 1 ), the treated substrate is loaded on the second plate  28  by the transfer chamber robot  52  (of  FIG. 1 ). Then, the untreated substrate  60  on the first plate  26  is transferred to the process chamber  30  (of  FIG. 1 ) by the transfer chamber robot  52  and the treated substrate on the second plate  28  is transferred from the load-lock chamber  20  by the storing unit robot  12  (of  FIG. 1 ). The load-lock chamber  20  has first and second doors  22  and  24  for transferring the substrate  60  on its sidewall. Even though not shown in  FIG. 2 , a driving cylinder may be connected to the first and/or second plates  26  and  28  for mowing the respective plate up and down. In addition, the first and second plates  26  and  28  have a pin  21  on their top surfaces for supporting the substrate  60 . 
     Before treating a substrate  60  in a cluster, a cassette including substrates treated in a previous step such as a cleaning step is loaded on the storing unit  10  (of  FIG. 1 ) and the substrates in the cassette are sequentially transferred to the load-lock chamber  20  by the storing unit robot  12  (of  FIG. 1 ). Moreover, the treated substrate in the load-lock chamber  20  is transferred to the cassette in the storing unit  10  (of  FIG. 1 ). 
     Generally, before and after a substrate is treated in a cluster, a step for the substrate such as a cleaning step is performed in apparatuses using an interior conveyor and the substrate is transferred between the apparatuses using an exterior conveyor such as an in-line conveyor system. Accordingly, a substrate is transferred from the conveyor to the cassette for a treatment in the cluster and the substrate treated in the cluster is transferred from the cassette to the conveyor. These transfers between the conveyor and the cassette interrupt an excellent performance in process flow. Moreover, since the transfers between the conveyor and the cassette require a long time period, process time increases and throughput decreases. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to an apparatus for a liquid crystal display device that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. 
     An object of the present invention is to provide an apparatus for a large-sized liquid crystal display device reducing a total process time. 
     Another object of the present invention is to provide an apparatus having an interior conveyor system. 
     Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
     To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, an apparatus for a liquid crystal display device includes: a process chamber for treating a substrate; a load-lock chamber having an interior conveyor; and a transfer chamber connected to the process chamber and the at least one load-lock chamber, the transfer chamber having a substrate-transferring means. 
     In another aspect, an apparatus for a liquid crystal display device includes: a plurality of process chambers for treating a substrate; at least one load-lock chamber having at least one interior conveyor; and a transfer chamber connected to the plurality of process chambers and the at least one load-lock chamber, the transfer chamber having a substrate-transferring means. 
     In another aspect, a method of transferring a substrate using an apparatus including a process chamber, a load-lock chamber having an interior conveyor, a transfer chamber, and an conveyor includes: providing the substrate adjacent to the load-lock chamber using the exterior conveyor; transferring the substrate from the exterior conveyor to the load-lock chamber by driving the interior conveyor; transferring the substrate from the load-lock chamber to the process chamber; treating the substrate in the process chamber; transferring the substrate from the process chamber to the load-lock chamber; and transferring the substrate from the load-lock chamber to the exterior conveyor by driving the interior conveyor. 
     In another aspect, a method of transferring a substrate using an apparatus including a plurality of process chambers, a first load-lock chamber having a first interior conveyor, a second load-lock chamber having a second interior conveyor, a transfer chamber, a first exterior conveyor and a second exterior conveyor includes; providing the substrate adjacent to the first load-lock chamber using the first exterior conveyor; transferring the substrate from the first exterior conveyor to the first load-lock chamber by driving the first interior conveyor; transferring the substrate from the first load-lock chamber to one of the plurality of process chambers; treating the substrate in the one of the plurality of process chambers; transferring the substrate from the one of the plurality of process chambers to the second load-lock chamber; and transferring the substrate from the second load-lock chamber to the second exterior conveyor by driving the second interior conveyor. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings: 
         FIG. 1  is a schematic view showing a cluster according to the related art; 
         FIG. 2  is a schematic cross-sectional view of a load-lock chamber for a cluster according to related art; 
         FIG. 3  is a schematic plane view showing a load-lock chamber for a cluster according to an embodiment of the present invention; 
         FIG. 4  is a schematic cross-sectional view showing a load-lock chamber for a cluster according to an embodiment of the present invention; 
         FIG. 5  is a schematic view showing an exemplary layout of an exterior conveyor and a cluster according to an embodiment of the present invention; 
         FIG. 6  is a schematic cross-sectional view showing another exemplary layout of an exterior conveyor and a cluster according to an embodiment of the present invention; and 
         FIGS. 7 to 10  are schematic cross-sectional views showing an operation of an exterior conveyor and a cluster of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to the preferred embodiments, examples of which are illustrated in the accompanying drawings. 
       FIG. 3  is a schematic plane view showing a load-lock chamber for a cluster according to an embodiment of the present invention. 
     In  FIG. 3 , a load-lock chamber  200  has a first door  220  for transfer of a substrate from and to an exterior conveyor and a second door  240  for connection to a transfer chamber on its sidewall. The load-lock chamber  200  includes at least one interior conveyor.  FIG. 3  shows only a first interior conveyor  400 . The first conveyor  400  has a plurality of rollers  430 , a plurality of roller-supporting rods  420  penetrating a central portion of each roller  430 , a driving unit (not shown) for supporting two ends of each roller-supporting rod  420  and rotating each roller-supporting rod  420 , and a supporter  410  connected to the driving unit. Since a substrate is loaded directly on the plurality of rollers  430 , an end portion of each roller  430  is separated from a center of each roller-supporting rod  420  with a predetermined space sufficient for an arm of a transfer chamber robot. In addition, the arm of the transfer chamber robot has a shape so that the arm of the transfer chamber robot can move into and out of the at least one conveyor  400  without contact with each roller  430 . For example, the arm of the transfer chamber robot may have a shape of fork. 
       FIG. 4  is a schematic cross-sectional view showing a load-lock chamber for a cluster according to an embodiment of the present invention. 
     In  FIG. 4 , the load-lock chamber  200  includes a first interior conveyor  400 , a second interior conveyor  500  under the first interior conveyor  400  and an up-and-down driving unit  260  moving the first and second interior conveyors  400  and  500  up and down. The time for exchanging substrates may be reduced by a multi-layered structure of the first and second interior conveyors  400  and  500 . When a substrate is transferred from and to an exterior conveyor (not shown), the up-and-down driving unit  260  moves the first and second interior conveyors  400  and  500  to have heights equal to a height of the exterior conveyor. If the height of the exterior conveyor is controllable, the up-and-down driving unit  260  may be omitted. 
       FIG. 5  is a schematic view showing an exemplary layout of an exterior conveyor and a cluster according to an embodiment of the present invention. 
     In  FIG. 5 , a cluster includes a load-lock chamber  200 , a transfer chamber  50  and a plurality of process chambers  30 . The cluster may further include a pre-heating chamber  40  for heating a substrate before a treatment in the plurality of process chambers  30 . The transfer chamber  50  may include a transfer chamber robot  52  as a substrate-transferring means transferring a substrate among the load-lock chamber  200 , the process chambers  30  and the pre-heating chamber  40 . The transfer chamber robot  52  may be operated using rotation and linear movement of an arm. The pre-heating chamber  40  may be omitted according to the process requirement and the number of the pre-heating chamber  40  may vary as the process. 
     In addition, a portion of an exterior conveyor  300  is arranged adjacent to a first door  220  of the load-lock chamber  200 . The exterior conveyor  300  may be used for a step prior or posterior to a treating step in the cluster such as a cleaning step. The exterior conveyor  300  may have its own driving unit independent of an up-and-down driving unit for first and second interior conveyors  400  and  500  (of  FIG. 4 ), or the exterior conveyor  300  and the first and second interior conveyors  400  and  500  (of  FIG. 4 ) may be driven by a single driving unit. The substrates are exchanged in the single load-lock chamber  200  and transferred to the exterior conveyor  300  and the transfer chamber  50 . 
     As a whole, the exterior conveyor  300  is directly connected to the transfer chamber robot  52  through the first and second interior conveyors  400  and  500  (of  FIG. 4 ) in the load-lock chamber  200 . 
       FIG. 6  is a schematic cross-sectional view showing another exemplary layout of an exterior conveyor and a cluster according to an embodiment of the present invention. 
     In  FIG. 6 , a cluster includes a first load-lock chamber  600 , a second load-lock chamber  700 , a transfer chamber  50  and a plurality of process chambers  30 . The cluster may further include a pre-heating chamber  40  for heating a substrate before a treatment in the plurality of process chambers  30 . The transfer chamber  50  may include a transfer chamber robot  52  transferring a substrate among the first load-lock chamber  600 , a second load-lock chamber  700 , the process chambers  30  and the pre-heating chamber  40 . The transfer chamber robot  52  may be operated using rotation and linear movement of an arm. The pre-heating chamber  40  may be omitted according to the process requirement and the number of the pre-heating chamber  40  may vary as the process. 
     The first load-lock chamber  600  has first and second doors  620  and  640 , and the second load-lock chamber  700  has third and fourth doors  720  and  740 . Two exterior conveyors  300  are arranged adjacent to the first door  620  of the first load-lock chamber  600  and the third door  720  of the second load-lock chamber  700 , respectively. An untreated substrate is transferred from one exterior conveyor  300  to the first load-lock chamber  600  and a substrate treated in the process chambers  30  is transferred from the second load-lock chamber  700  to the other exterior conveyor  300 . The substrate is transferred from the exterior conveyor  300  to the transfer chamber  50  in the first load-lock chamber  600 , while the substrate is transferred form the transfer chamber  50  to the exterior conveyor  300  in the second load-lock chamber  700 . Accordingly, the substrates may not be exchanged in the first and second load-lock chambers  600  and  700 . As a result, each of the first and second load-lock chambers  600  and  700  may have a single interior conveyor therein. 
     When each load-lock chamber  600  and  700  has a single interior conveyor, the untreated substrate transferred from the exterior conveyor  300  may be loaded on an interior conveyor in the first load-lock chamber  600  and then may be transferred to the process chambers  30  by the transfer chamber robot  50 . In addition, the substrate treated in the process chambers  30  is loaded on an interior conveyor in the second load-lock chamber  700  by the transfer chamber robot  52 . Accordingly, the interior conveyor of the first and second load-lock chambers  600  and  700  may be fixed to have heights equal to respective heights of the exterior conveyors  300 . 
     As a whole, the exterior conveyors  300  are directly connected to the transfer chamber robot  52  through the respective interior conveyors in the first and second load-lock chambers  600  and  700 . 
       FIGS. 7 to 10  are schematic cross-sectional views showing an operation of an exterior conveyor and a cluster of  FIG. 5 . 
     In  FIG. 7 , a substrate  60  treated in a prior step such as a cleaning step is moved by an exterior conveyor  300  and provided at a front of a first door  220  of a load-lock chamber  200 . 
     In  FIG. 8 , the first door  220  is open and the substrate  60  is loaded on a first interior conveyor  400  through the first door  220  by driving the exterior conveyor  300 . At the same time, the first interior conveyor  400  may be driven by a driving unit (not shown) to adjust a position of the substrate  60  properly. In addition, the first interior conveyor  400  may be driven by an up-and-down driving unit  260  (of  FIG. 4 ) to have substantially the same height as a height of the exterior conveyor  300 . 
     In  FIG. 9 , after the substrate  60  is completely loaded on the first interior conveyor  400 , the first door  220  is closed and the load-lock chamber  200  may be evacuated. Then, a second door  240  is open and a transfer chamber robot  52  of a transfer chamber  50  is disposed under the substrate  60 . 
     In  FIG. 10 , the substrate  60  is transferred to the transfer chamber  50  by the transfer chamber robot  52 . 
     Then, the substrate  60  is transferred to a plurality of process chambers  30  (of  FIG. 5 ) and is treated for a step such as a deposition step and an etch step. After finishing the treatment step in the process chambers  30  (of  FIG. 5 ), the substrate  60  is transferred to the load-lock chamber  200  by the transfer chamber robot  52  and is loaded on a second interior conveyor  500 . Then, the second door  240  is closed and the load-lock chamber  200  is pressurized to have an atmospheric pressure. Then, the first door  220  is open and the substrate  60  is transferred to the exterior conveyor  300  through the first door  220  by driving the second interior conveyor  500 . At the same time, the exterior conveyor  300  may be driven by a driving unit (not shown) to adjust a position of the substrate  60  properly. In addition, the second interior conveyor  500  may be driven by an up-and-down driving unit  260  (of  FIG. 4 ) to have substantially the same height as a height of the exterior conveyor  300 . 
     Consequently, since a load-lock chamber has an interior conveyor therein, a substrate treated in a prior step is transferred from an exterior conveyor directly to a load-lock chamber and a substrate treated in a process chamber of a cluster is transferred from a load-lock chamber directly to an exterior conveyor. Accordingly, a storing unit for substrates, a storing unit robot and a cassette are not required, thereby production cost and fabrication time reduced. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the apparatus having a conveyor without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.