Abstract:
A substrate transfer apparatus includes first and second blades configured for supporting a substrate at different heights, respectively; an arm part connected to the first and second blades to move the first and second blades; and a drive unit configured for driving the first and second blades and the arm part, wherein the first and second blades are folded or unfolded while revolving on the same (single) axis of the arm part. According to the substrate transfer apparatus, a substrate processing throughput increases relative to a system area and time required for transferring and processing a substrate is reduced.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This U.S. non-provisional patent application claims priority under 35 U.S.C §119 of Korean Patent Application 2006-62671 filed on Jul. 4, 2006, the entirety of which is hereby incorporated by reference. 
       BACKGROUND 
       [0002]    The present invention relates to a substrate processing system and, more specifically, to a substrate processing system which is capable of reducing a footprint area while increasing a substrate processing throughput. 
         [0003]    A cluster system is generally referred to as a multi-chamber substrate processing system including a transfer robot (or handler) and a plurality of processing modules arranged around the transfer robot. In recent years, the demand of cluster systems having a batch-processing function is increasing for liquid crystal displays (LCDs), plasma display panels (PDPs), semiconductor manufacturing apparatuses etc. A cluster system includes, for example, a transfer chamber and a transfer robot which is rotatable inside the transfer chamber. A processing module, such as a process chamber, may be mounted on each side of the transfer chamber. 
         [0004]    However, a conventional cluster system includes a transfer robot configured to transfer only one object (e.g., substrate) at a time and a process chamber in which only one object is processed. This leads to increase of total processing time required for processing a substrate inside the system. As a result, a production speed is reduced and the cost of end products increases. 
       SUMMARY OF THE INVENTION 
       [0005]    Exemplary embodiments of the present invention are directed to a substrate transfer apparatus for transferring a substrate to a process chamber. In an exemplary embodiment, the substrate transfer apparatus may include first and second blades configured for supporting a substrate at different heights, respectively; an arm part connected to the first and second blades to move the first and second blades; and a drive unit configured for driving the first and second blades and the arm part, wherein the first and second blades are folded or unfolded while revolving on the same axis of the arm part. 
         [0006]    Exemplary embodiments of the present invention are directed to a substrate processing apparatus. In an exemplary embodiment, the substrate processing apparatus may include at least one process chamber with susceptors on which a substrate is loaded; a transfer chamber connected to the process chamber; and a substrate transfer apparatus installed inside the transfer chamber for simultaneously transferring substrates to the susceptors of the process chamber. 
         [0007]    In another exemplary embodiment, the substrate transfer apparatus may include a transfer chamber; a pair of process chambers each having a susceptor, the pair of process chambers being juxtaposed at one side of the transfer chamber; and a substrate transfer apparatus installed inside the transfer chamber for simultaneously transferring substrates to susceptors of the pair of process chambers. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a top plan view illustrating a configuration of a substrate processing system according to the present invention. 
           [0009]      FIG. 2  is a perspective view of a processing unit of the substrate processing system illustrated in  FIG. 1 . 
           [0010]      FIG. 3  is a side sectional view of a processing unit illustrated in  FIG. 2  to describe a substrate transfer apparatus installed at a transfer chamber. 
           [0011]      FIG. 4  is a side sectional view of an exemplary drive unit configured to rotate first and second blades, an upper arm, and a lower arm. 
           [0012]      FIG. 5A  and  FIG. 5B  are a top plan view and a side sectional view of a processing unit where first and second blades of a substrate transfer apparatus overlap each other. 
           [0013]      FIG. 6A  and  FIG. 6B  are a top plan view and a side sectional view of a processing unit where first and second blades of a substrate transfer apparatus spread out. 
           [0014]      FIG. 7  illustrates a processing unit where chambers each having one susceptor are juxtaposed. 
           [0015]      FIG. 8  is an exemplary diagram illustrating an upper arm where first and second blade drive units are installed. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0016]    The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention, however, may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. Like numbers refer to like elements throughout. 
         [0017]      FIG. 1  is a top plan view illustrating a configuration of a substrate processing system according to the present invention, and  FIG. 2  is a perspective view of a processing unit of the substrate processing system illustrated in  FIG. 1 .  FIG. 3  is a side sectional view of a processing unit illustrated in  FIG. 2  to describe a substrate transfer apparatus installed at a transfer chamber. 
         [0018]    Referring to  FIG. 1  through  FIG. 3 , an index  110  called an equipment front end module (EFEM) is installed at the substrate transfer system. The index  110  includes a frame  112  and a load station (or FOUP opener)  114  configured to open and close the cover of a FOUP (so-called “carrier”). Two FOUPs  104  each containing a substrate W are loaded on the load station  114  by means of a logistic automation system (e.g., OHT, AGV, RGV, etc.). The FOUPs  104  are typical lot carriers for manufacturing. 
         [0019]    Inside the frame  112 , a transfer robot  118  is installed to transfer a substrate W between the FOUP  104  loaded on the load station  114  and the processing unit  120 . Namely when operating once, the transfer robot  118  takes out at least one substrate W from the FOUP  104  loaded on the load station  114  and carries the taken-out substrate W to a buffer stage  124  of a loadlock chamber  122 . The transfer robot  118  installed at the index  110  may be one of various robots for use in semiconductor manufacturing processes. 
         [0020]    As illustrated in  FIG. 1 , the processing unit  120  is disposed at the back of the index  110 . The processing unit  120  includes two loadlock chambers  122 , a transfer chamber  130 , process chambers  140 , and a substrate transfer apparatus  150 . 
         [0021]    The transfer chamber  130  is a polygonal chamber disposed at the center of the processing unit  120 . Each of the loadlock chambers  122  is also disposed between the index  110  and the transfer chamber  130  and includes a buffer stage  124  on which a substrate to be processed or a processed substrate is placed. Conventionally, the loadlock chambers  122  function as buffer spaces between two different environments such as, for example, an atmospheric environment and a vacuum environment. A substrate to be processed (or a substrate processed in the process chamber) stays in the loadlock chamber  122  for a while. 
         [0022]    The process chambers  140  are disposed at each side of the transfer chambers  130  to perform a predetermined process for two substrates, respectively. First and second susceptors  142   a  and  142   b  are juxtaposed inside the process chamber  140  to simultaneously perform a process for two substrates. The first and second susceptors  142   a  and  142   b  are disposed to face a substrate entrance. Although not shown in the figures, it will be understood that the first and second susceptors  142   a  and  142   b  have basic functions such as receiving/transferring a substrate from/to the substrate transfer apparatus  150  (which is conventionally done by means of a lift pin assembly installed at a susceptor), holding a substrate while processing the same, and offering a uniform thermal environment to a substrate according to a processing temperature. 
         [0023]    The process chamber  140  may be configured for performing a variety of substrate processing operations. A process chamber may be, for example, an ashing chamber configured for removing a photoresist using plasma or a CVD chamber configured for depositing an insulation layer or an etch chamber configured for etching apertures or openings of an insulation layer to form interconnect structures or a PVD chamber configured for depositing a barrier layer or a PVD chamber configured for depositing a metal layer. 
         [0024]    As illustrated in  FIG. 7 , two process chambers  140 ′ are juxtaposed at each side of a transfer chamber  130 . Each of the process chambers  140 ′ includes a susceptor  142   a.  The same process may be performed at the process chambers  140 ′ juxtaposed at each side of the transfer chamber  130 . In case of an etching (or deposition) process whose process conditions should be regulated minutely, one substrate is preferably processed inside each process chamber  140 ′ (see  FIG. 7 ). In case of an ashing process whose process conditions need not be regulated minutely, a plurality of substrates may be processed inside one process chamber  140  (see  FIG. 1 ). 
         [0025]      FIG. 5A  and  FIG. 5B  are a top plan view and a side sectional view of a processing unit where first and second blades of a substrate transfer apparatus overlap each other.  FIG. 6A  and  FIG. 6B  are a top plan view and a side sectional view of a processing unit where first and second blades of a substrate transfer apparatus spread out. 
         [0026]    As illustrated in  FIG. 1  through  FIG. 4 , a substrate transfer apparatus  150  is installed at the transfer chamber  130 . The substrate transfer apparatus  150  has a special structure to transfer two substrates per one operation. 
         [0027]    The substrate transfer apparatus  150  includes first and second blades configured for loading/unloading two substrates to/from the first and second susceptors  142   a  and  142   b  of the process chamber  140  at one time. Especially, the substrate transfer apparatus  150  has a structure that is suitable for transferring substrates tothe process chamber  140  including the first and second susceptors  142   a  and  142   b  disposed side by side. 
         [0028]    Further, the substrate transfer apparatus  150  includes first and second blades  152  and  154 , an arm part  160 , a rotation body  170 , and a drive unit  180 . 
         [0029]    The rotation body  170  is a cylindrical body disposed at the center of the transfer chamber  130 . The drive unit  180  is disposed inside the rotation body  170 . The rotation body  170  is rotatable and elevatable on its axis by means of a rotation member  172  and an elevation member  174 . 
         [0030]    The arm part  160  includes an upper arm  162  and a lower arm  164  which revolve horizontally. One end of the upper arm  162  is coupled with the first and second blades  152  and  154 , and one end of the lower arm  164  is coupled with the other end of the upper arm  162 . The other end of the lower arm  164  is coupled with the rotation body  170 . The fist and second blades  152  and  154  rotate on the same (single) axis of the upper arm  162 . The upper arm  162  may rotate relatively to the lower arm  164 . Further, the lower arm  164  rotates relatively to the rotation body  170 . 
         [0031]    The first and second blades  152  and  154  are sequentially stacked and revolvably installed at one end of the upper arm  162 . Each of the first and second blades  152  and  154  has an aperture whose one side is open. Supports  153  are mounted on top surfaces of the first and second blades  152  and  154 , respectively. The edge of a substrate is loaded on the support  153 . The substrate transfer apparatus  150  may include a vacuum line (not shown) configured for selectively vacuum-absorbing a substrate to the support  153  of the first and second blades  152  and  154  or a edge clamp (not shown) configured for mechanically clamping the edge of a substrate. 
         [0032]    The first and second blades  152  and  154  are folded or unfolded by a revolving operation on the same axis of the upper arm  162 . The revolving directions of the first and second blades  152  and  154  are opposite to each other. As illustrated in  FIG. 5A  and  FIG. 5B , the first blade  152  and the second blade  154  take out substrates W from the buffer stages  124  of the loadlock chamber  122  while they overlap each other. As illustrated in  FIG. 6A  and  FIG. 6B , the first blade  152  and the second blade  154  deliver substrates W to the first and second susceptors  142   a  and  142   b  of the process chamber  140  while they are unfolded. As stated above, a substrate transfer apparatus may transfer two substrates at a time and direction of first and second blades may change while they are folded. Thus, a space of a transfer chamber may decrease. 
         [0033]    The drive unit  180  includes first and second arm drive units  182  and  184  configured for horizontally revolving the upper and lower arms  162  and  164 , respectively and first and second blade drive units  186  and  188  configured for oppositely revolving the first and second blades  152  and  154 . 
         [0034]      FIG. 4  is a side sectional view of an exemplary drive unit  170  configured to rotate first and second blades  152  and  154 , an upper arm  162 , and a lower arm  164 . 
         [0035]    Referring to  FIG. 4 , a lower arm rotation shaft  164   a  extends vertically downwardly to a rotation body  170  from one end of the lower arm  164 . A second arm drive unit  184  revolves the lower arm  164  on the rotation body  170 , about a lower arm rotation axis  164   a . The second arm drive unit  184  includes a first drive motor  184   a,  a pulley  184   b  configured for transmitting a power of the first drive motor  184   a  to the lower arm rotation shaft  164   a,  and a belt  184   c.    
         [0036]    An upper arm rotation shaft  162   a  extends vertically downwardly to the lower arm  164  from one end of the upper arm  162 . A first arm drive unit  182  revolves the upper arm  162  on the lower arm about a upper arm rotation shaft  162   a.  The first arm drive unit  182  includes a second drive motor  182   a,  a plurality of pulleys  182   b  configured for transmitting a power of the second drive motor  182   a  to the upper arm rotation shaft  162   a,  and a belt  182   c.    
         [0037]    A fitst blade rotation shaft  152   a  extends vertically downwardly to the upper arm  162  from one end of the first blade  152 . The first blade drive unit  186  revolves the first blade  152  on the upper arm  162 , on the basis of the first blade rotation axis  152   a.  A first blade drive unit  186  includes a third drive motor  186   a,  a plurality of pulleys  186   b  configured for transmitting a power of the third drive motor  186   a  to the first blade rotation axis  152   a,  and a belt  186   c.    
         [0038]    A second blade rotation shaft  154   a  extends vertically downwardly to the upper arm  164  through the first blade rotation shaft  152   a  from one end of the second blade  154 . A second blade drive unit  188  revolves the second blade  154  on the upper arm  164 , about the second blade rotation axis  154   a.  The second blade drive unit  188  includes a fourth drive motor  188   a,  a plurality of pulleys  188   b  configured for transmitting a power of the fourth drive motor  188   a  to the second blade rotation shaft  154   a , and a belt  188   c.    
         [0039]    As illustrated in  FIG. 8 , the first and second blade drive units  186  and  188  are installed at the upper arm  164  to directly rotate the first and second blades  152  and  154 , respectively. Likewise in the case where the first and second blade drive units  186  and  188  are installed at the upper arm  164 , there is an advantage to omit a complex power transmission structure including a plurality of pulleys, a belt or the like. 
         [0040]    As mentioned above, the lower arm rotation shaft  164   a,  the upper arm rotation shaft  162   a,  and the first and second blade rotation shafts  152   a  and  154   a  receive a power (rotation force) from their drive motors  182   a,    184   a,    186   a,  and  188   a  through mechanism such as a pulley (pulleys) and a belt, respectively. 
         [0041]    The first and second drive motors  182   a  and  184   a  are independently controlled to locate the upper and lower arms  162  and  164  at a shrinkage (folded) position and an extension position, respectively. For example, the upper and lower arms  162  and  164  may be controlled to rotate by one arm drive unit. The third and fourth drive motors  186   a  and  188   a  are independently controlled to locate the first and second blades  152  and  154  at an overlap position (see  FIG. 5A ) and a bidirectionally unfolded position (see  FIG. 6A ). 
         [0042]    The drive motors  182   a,    184   a,    186   a,  and  188   a  of the substrate transfer apparatus  150  are controlled by a controller with kinematical equations programmed to define the number of steps required for locating the arms  162  and  164  and the first and second blades  152  and  154  at target positions. 
         [0043]    A procedure of transferring a substrate from a loadlock chamber to a process chamber using a substrate transfer apparatus will now be described below. Further, it will be understood that the present invention may be applied to transfer substrates between various chambers of a substrate processing system. 
         [0044]      FIG. 5A  and  FIG. 5B  illustrate the procedure that a substrate transfer apparatus takes out two substrates from a loadlock chamber. As illustrated in the figures, the first and second blades  152  and  154  take out two substrates W from a buffer stage  124  of a loadlock chamber  122  while first and second blades  152  and  154  overlap each other. 
         [0045]      FIG. 6A  and  FIG. 6B  illustrate the procedure that a substrate transfer apparatus loads two substrates taken out of a loadlock chamber on first and second susceptors of a process chamber. As illustrated in the figures, first and second blades  152  and  154  travel over first and second susceptors  142   a  and  142   b  of a process chamber  140  while they are unfolded in both-sided directions. Substrates W are lifted from the first and second blades  152  and  154  by lift pins ascending from a upper surface of the first and second susceptors  142   a  and  142   b  to loading position. At this time, the first and second blades  152  and  154  return to a standby position (where an upper arm and a lower arm are folded) of a transfer chamber  130 . When the first and second blades  152  and  154  are taken out of the process chamber  140 , lift pins are descended to place a substrate W on the first and second susceptors  142   a  and  142 . 
         [0046]    According to the present invention, a substrate processing system is capable of reducing a footprint area while increasing a substrate processing throughput. Further, the substrate processing system is capable of reducing time required for transferring and processing a substrate. 
         [0047]    Although the present invention has been described in connection with the embodiment of the present invention illustrated in the accompanying drawings, it is not limited thereto. It will be apparent to those skilled in the art that various substitutions, modifications and changes may be made without departing from the scope and spirit of the invention.