Abstract:
A sawing and sorting system combines a sawing apparatus and a sorting apparatus. The sawing and sorting system comprises a loader. The loader comprises a magazine receiving a plurality of strips. A mounting unit mounts the strip thereon. A plurality of transfer and sawing robots each comprises a picker unit. The picker unit comprises a rotatable chuck table. The transfer and sawing robot transfers the picker unit horizontally and vertically. The rotatable chuck table holds the strip. The picker unit rotates the rotatable chuck table. A plurality of sawing spindle units each comprises a rotary blade. The sawing spindle unit moves the blade horizontally to divide the strip into unit packages. A cleaning unit cleans the unit package. A test means inspects the unit package according to a test criteria. A sorting table mounts the unit package for sorting. An unloader provides trays. A sorting transfer robot sorts the unit packages into the trays.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This U.S. non-provisional application claims priority and benefit of Korean Patent Application No. 2004-71767, filed on Sep. 8, 2004, the entire contents of which are herein incorporated by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates to an apparatus for manufacturing semiconductor chip packages and, more particularly, to a sawing and sorting system.  
         [0004]     2. Description of the Related Art  
         [0005]     For a semiconductor chip package, for example a fine pitch ball grid array and a tape ball grid array, a substrate strip (hereinafter referred to as a strip) may be used during a die attaching process, a wire bonding process, and a molding process. The substrate strip, which may comprise a plurality of unit substrates, is divided into unit semiconductor chip packages (hereinafter referred to as unit packages). The unit packages are then tested and sorted into good or faulty packages.  
         [0006]     A sawing and sorting system performs a sawing process and a sorting process. The sawing and sorting processes include a cleaning process to remove debris and/or moisture from the unit packages and a visual test process to inspect the appearance of the unit packages.  
         [0007]      FIG. 1  is a schematic plan diagram of a conventional sawing and sorting system.  FIG. 2  is a schematic cross-sectional diagram of a sawing process by a sawing apparatus of a conventional sawing and sorting system.  
         [0008]     Referring to  FIGS. 1 and 2 , the conventional sawing and sorting system  300  comprises a sawing apparatus  303  and a sorting apparatus  301 . The sawing apparatus  303  divides a strip  1  into unit packages  5 . The sawing apparatus  303  includes a rotatable chuck table  335 , a sawing spindle unit  361  having a blade  363 , and a nozzle unit  365 . The sorting apparatus  301  sorts the unit packages  5  according to their quality. The sorting apparatus  301  includes a loader  310 , a transfer robot  330  having a picker unit  331 , vision cameras  355  and  357 , a cleaning unit  373 , a drying unit  376 , a turntable  375 , a sorting table  381 , a buffer table  377 , a sorting transfer robot  385 , and an unloader  393  having trays  7 ,  8  and  9 . The sorting apparatus  301  and the sawing apparatus  303  may be installed adjacent to each other so that the sorting process and the sawing process may be performed consecutively.  
         [0009]     In the conventional sawing and sorting system  300 , the transfer robot  330  moves between the sawing apparatus  303  and the sorting apparatus  301 . The rotatable chuck table  335  of the sawing apparatus  303  and the cleaning unit  373 , the turntable  375 , the drying unit  376 , the buffer table  377 , and the sorting table  381  of the sorting apparatus  301  are arranged along the traveling route of the picker unit  331  of the transfer robot  330 .  
         [0010]     The operation of the conventional sawing and sorting system  300  is now described. The sawing process begins with a magazine  3  having the strip  1  being provided in the loader  310 . The strip  1  is mounted one after another on a guide rail  321  by a pusher  317  and a gripper  319 . The strip  1  is moved to a pick up position of the picker unit  331  of the transfer robot  330 , which transfers the strip  1  to the rotatable chuck table  335 .  
         [0011]     The rotatable chuck table  335  supports the strip  1  by vacuum. The blade  363  of the sawing spindle unit  361  saws the strip  1  in one direction. After sawing the strip  1  in one direction, the rotatable chuck table  335  rotates through 90 degrees. The blade  363  then saws the strip  1  in another direction. The strip  1  is divided into unit packages  5 . The rotatable chuck table  335  also supports the unit package  5  by vacuum.  
         [0012]     During the sawing process, debris may be generated. Debris remaining on the rotatable chuck table  335  may cause an operational error to a subsequent process and/or hinder a stable sawing operation and thus, should be removed.  
         [0013]     The cleaning process begins with the nozzle unit  365 , installed adjacent to the blade  363 , ejecting a cleaning solution at a high pressure and removing the debris. Next, the picker unit  331  of the transfer robot  330  absorbs the unit package  5  by vacuum and moves the unit package  5  to the cleaning unit  373 . The cleaning unit  373  cleans the unit package  5  using the cleaning solution and/or air. The cleaning operation is performed on one surface of the unit package  5 , i.e., the surface opposite to the surface wherein the solder balls  6  are formed. After cleaning one surface of the unit package  5 , the unit package  5  is transferred to and mounted on the turntable  375 . The turntable  375 , rotatable through 180 degrees, inverts the unit package  5  to allow the other surface to be cleaned and dried.  
         [0014]     After sawing and cleaning, the unit packages are then tested and sorted into good or faulty packages. A first vision camera  355  inspects one surface of the unit package  5 . The unit package  5  is temporarily mounted on the buffer table  377 . The picker unit  331  transfers the unit package  5  to the sorting table  381 . A second vision camera  357  inspects the other surface of the unit package  5 . The sorting transfer robot  385  sorts the unit package  5  into, for example, the tray  7  for good packages or the tray  8  for faulty packages.  
         [0015]     Thus, the conventional sawing and sorting system may have a sawing apparatus and a sorting apparatus formed separately and independently. If a target of operation is changed, a new tool and/or parameter may be set on each of the sawing apparatus and the sorting apparatus.  
         [0016]     The conventional sawing and sorting system removes debris using a cleaning solution and air, which results in consumption of a considerable amount of cleaning solution and air and an increased cleaning time. The conventional sawing and sorting system also includes first and second cleaning operations, thereby resulting in reduced productivity and an inefficient cleaning operation.  
         [0017]     Further, the conventional sawing and sorting system may include operations substantially unrelated to the sawing and sorting operations, for example a strip and/or unit package transfer operation, a visual test operation, a cleaning operation and a drying operation.  
       SUMMARY OF THE INVENTION  
       [0018]     An exemplary embodiment of the invention is directed to a sawing and sorting system, in which a combination of a sawing apparatus and a sorting apparatus may facilitate change and/or maintenance of a tool and/or parameter.  
         [0019]     Another exemplary embodiment of the invention is directed to a sawing and sorting system, in which the amount of a cleaning solution and/or air used in a cleaning operation may be reduced and the cleaning time may be reduced.  
         [0020]     Another exemplary embodiment of the invention is directed to a sawing and sorting system, in which the time of operations other than sawing and sorting operations may be reduced, thereby improving productivity.  
         [0021]     In an exemplary embodiment, a sawing and sorting system combines a sawing process and a sorting process. The sawing and sorting system comprises a loader having a magazine receiving a plurality of strips. A mounting unit, which may include a guide rail, mounts the strip on a plurality of transfer and sawing robots, each transfer and sawing robot comprising a picker unit having a rotatable chuck table, which holds the strip by vacuum. The picker unit is preferably movable in horizontal and vertical directions. The sawing and sorting system comprises a plurality of sawing spindle units, each having a rotary blade. The sawing spindle unit moves the blade horizontally to divide the strip into unit packages. A cleaning unit cleans the unit package. A sorting table mounts the unit package for sorting. A test means inspects the unit package according to predetermined test criteria. An unloader provides trays. A sorting transfer robot sorts the unit package into the trays according to the test results.  
         [0022]     The sawing spindle unit, the cleaning unit and the sorting table are preferably arranged in order, spaced from the mounting unit. In an exemplary embodiment, there are two transfer and sawing robots. The picker units of the transfer and sawing robots preferably face in opposite directions to avoid a collision.  
         [0023]     In an exemplary embodiment, there are two sawing spindle units. The sawing spindle units preferably move perpendicularly to the traveling direction of the picker unit. Preferably, each sawing spindle unit independently moves in horizontal and vertical directions.  
         [0024]     In an exemplary embodiment, the sawing and sorting system includes a plurality of the sorting tables.  
         [0025]     The sawing and sorting system further comprises a vision camera and an alignment table located between the mounting unit and the sawing spindle unit.  
         [0026]     In an exemplary embodiment, the transfer and sawing robots may perform separate operations. While one of the transfer and sawing robots may perform a sawing operation, the other transfer and sawing robot may perform cleaning, drying and sorting operations and start an alignment operation for a new strip. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]     The above and other features and advantages of embodiments of the invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements.  
         [0028]      FIG. 1  is a schematic plan diagram of a conventional sawing and sorting system.  
         [0029]      FIG. 2  is a schematic cross-sectional diagram of a sawing process by a sawing apparatus of a conventional sawing and sorting system.  
         [0030]      FIG. 3  is a schematic perspective diagram of a sawing and sorting system in accordance with an exemplary embodiment of the invention.  
         [0031]      FIG. 4  is a schematic plan diagram of a sawing and sorting system in accordance with an exemplary embodiment of the invention.  
         [0032]      FIG. 5  is a schematic perspective diagram of a transfer and sawing robot of a sawing and sorting system in accordance with an exemplary embodiment of the invention.  
         [0033]      FIG. 6  is a schematic perspective diagram of a sawing spindle unit of a sawing and sorting system in accordance with an exemplary embodiment of the invention.  
         [0034]      FIG. 7  is a schematic cross-sectional diagram of a sawing process by a sawing and sorting system in accordance with an exemplary embodiment of the invention.  
         [0035]      FIG. 8  is a timing chart illustrating the operation of a sawing and sorting system in accordance with an exemplary embodiment of the invention. 
     
    
       [0036]     These drawings are provided for illustrative purposes only and are not drawn to scale. The spatial relationships and relative sizing of the elements illustrated in the various embodiments may have been reduced, expanded, or rearranged to improve the clarity of the figure with respect to the corresponding description. The figures, therefore, should not be interpreted as accurately reflecting the relative sizing or positioning of the corresponding structural elements that could be encompassed by an actual device manufactured according to the exemplary embodiments of the invention.  
       DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0037]     The invention will be described below with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. It will be appreciated that the invention may be embodied in many different forms and should not be construed as limited to the particular embodiments set forth herein. Rather, the disclosed 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.  
         [0038]     Well-known structures and processes have not been described or illustrated in detail to avoid obscuring the invention. For simplicity and clarity of illustration, some elements illustrated in the figures may not be drawn to scale. For example, the dimensions of some of the elements may be exaggerated or reduced relative to other elements for clarity.  
         [0039]     Referring to  FIGS. 3 and 4 , an exemplary embodiment of a sawing and sorting system  100  combines a sawing process and a sorting process. The sawing and sorting system  100  comprises transfer and sawing robots  30  and  40 , sawing spindle units  61  and  62 , cleaning units  71  and  72 , and sorting tables  81  and  82 . The sawing and sorting system  100  further comprises a loader  10 , a guide rail  21 , an unloader  93  having trays  7 ,  8  and  9 , and vision cameras  55  and  57 .  
         [0040]     The functions of the elements of the sawing and sorting system  100  are now described.  
         [0041]     The loader  10  is preferably installed at one end of the sawing and sorting system  100 . The loader  10  comprises a magazine  3  for receiving the strip  1 . The loader  10  further comprises an elevator  15 , which moves the magazine vertically, and a pusher  17 , which pushes the strip  1  received in the magazine  3  to the guide rail  21 . The guide rail  21  mounts the strip  1  on the transfer and sawing robots  30  and  40  by guiding the strip  1  to a pickup position of the first and second transfer and sawing robots  30  and  40 . The guide rail  21  may use an air pressure cylinder or a belt driven by a motor.  
         [0042]     A first vision camera  51  and an alignment table  37  are preferably located at one side of the guide rail  21 . The first vision camera  51  and the alignment table  37  are preferably installed and movable on their operating rails  52  and  38 , respectively, which extend in the Y direction. Reference numeral  39  is a tool station.  
         [0043]     The transfer and sawing robots  30  and  40  extend in the X direction and comprise picker units  31  and  41 , respectively. In one embodiment, the picker unit  31  is preferably configured as shown in  FIG. 5 . The picker units  31  and  41  each comprise a rotatable chuck table  35 . The strip  1  and/or a unit package  5  may be held under the rotatable chuck table  35  by vacuum. The picker units  31  and  41  are preferably movable in the X and Z directions and face in opposite directions so that the transfer and sawing robots  30  and  40  may perform separate operations. The picker units  31  and  41  also preferably have rotation axes  33  and  43 , respectively, to change the sawing orientation and adjust the sawing position.  
         [0044]     Referring back to  FIGS. 3 and 4 , the sawing spindle units  61  and  62  are located in the traveling route of the picker units  31  and  41 . The sawing spindle units  61  and  62  are preferably of a so-called twin type to allow a double sawing performance. The sawing spindle units  61  and  62  are also preferably movable in the X, Y and Z directions to adjust their vertical and horizontal separation. The movement direction of each of the sawing spindle units  61  and  62  may be adjustable, if necessary. For example, the sawing spindle unit  61  may be movable in the Z direction and the sawing spindle unit  62  may be movable in the X direction.  
         [0045]     In the embodiment shown in  FIG. 6 , the sawing spindle units  61  and  62  are installed and movable on guide axes  65  and  66 , respectively, which extend in the Y direction. The guide axes  65  and  66  may be modified to various types, for example a rail type.  
         [0046]     As shown in  FIG. 4 , the cleaning units  71  and  72  are preferably located adjacent to the sawing spindle units  61  and  62 . The cleaning units  71  and  72  clean and dry the top and bottom surfaces of the strip  1 . The cleaning and drying processes may be performed consecutively.  
         [0047]     Referring again to  FIGS. 3 and 4 , the sorting tables  81  and  82  are preferably located adjacent to the cleaning units  71  and  72 . The sorting tables  81  and  82  are installed and movable on sorting table rails  83  and  84 , respectively, which extend in the Y direction. A second vision camera  55  is located above the sorting tables  81  and  82  along the traveling route of the sorting tables  81  and  82 . The second vision camera  55 , installed and movable on a second camera rail  56 , inspects one surface of the unit package  5 .  
         [0048]     A tray guide rail  91 , located adjacent to the sorting tables  81  and  82 , guides the movement of the trays  7  and  8 . A tray transfer unit  95  transfers the trays  7  and  8  from the tray guide rail  91  to the unloader  93 . When trays  7  and  8  are already filled with packages, tray  9  may be provided for receiving packages next. The tray transfer unit  95  also transfers the tray  9  to the tray guide rail  91 .  
         [0049]     A third vision camera  57 , located between the tray guide rails  91 , inspects the other surface of the unit package  5 . The third vision camera  57  is installed and movable on a third camera rail  58 , which extends in the Y direction. A sorting transfer robot  85  moves between the sorting tables  81  and  82  and the tray guide rail  91 . The sorting transfer robot  85  sorts the unit package  5  according to the test results.  
         [0050]     The operation of a sawing and sorting system in accordance with the exemplary embodiment of the invention will be described. The magazine  3  receiving the strip  1  is provided in the loader  10 . The strip  1  is mounted on the guide rail  21  and then moved to a pickup position of the first and second transfer and sawing robots  30  and  40 . The picker units  31  and  41  of the first and second transfer and sawing robots  30  and  40  absorbs the strip  1  by vacuum and transfers the strip  1  above the first vision camera  51 . The first vision camera  51  inspects the strip alignment on the picker units  31  and  41 . If the strip alignment is incorrect, the picker units  31  and  41  place the strip  1  on the alignment table  37 . The strip alignment is adjusted by rotating the picker units  31  and  41  along the rotation axes  33  and  43 , respectively. If the strip alignment is correct, the picker units  31  and  41  move the strip  1  to the sawing spindle units  61  and  62 .  
         [0051]     To begin the sawing process, either the picker units  31  and  41  move downward or the sawing spindle units  61  and  62  move upward. The rotary blades  63  and  64  then saw the strip  1  in one direction, together with the Y-axis movement of the sawing spindle units  61  and  62 . After the strip  1  is sawn in one direction, the blades  63  and  64  are withdrawn from the strip  1 . To begin sawing in the other direction, the picker units  31  and  41  rotate through  90  degrees by rotation of the rotation axes  33  and  43 . Next, either the picker units  31  and  41  move downward or the sawing spindle units  61  and  62  move upward. The rotary blades  63  and  64  then saw the strip  1  in the other direction. The operation of the two sawing spindle units  61  and  62  may allow a reduced time of the sawing process.  
         [0052]     In the case of a flexible substrate such as a tape type or film type, a strip carrier or frame (not shown) may support the substrate strip. However, the strip carrier supporting the strip  1  may be unnecessary after the sawing process. Thus, after the sawing process, the strip carrier supporting the strip  1  is received in a carrier box  79 .  
         [0053]     During the sawing process, debris may be generated. Conventionally, debris generated during the sawing process was separated from the strip  1  and/or unit packages  5  using a cleaning solution. In some instances, debris may drift onto the unit packages  5  due to the spraying of the cleaning solution. Thus, the conventional art may require a considerable cleaning time to completely separate debris from the unit packages  5 .  
         [0054]     In the exemplary embodiment of the sawing and sorting system  100 , debris generated during the sawing process may be removed during the sawing process. Contrary to the conventional art as shown in  FIG. 2 , in the sawing and sorting system  100 , the unit packages  5  may be held below the rotatable chuck table  35  by vacuum as shown in  FIG. 7 . A nozzle unit  67  installed adjacent to the blade  63  sprays a cleaning solution toward the unit packages  5 . Therefore, debris generated during the sawing process is also separated from unit packages  5  by gravity. Thus, the use of gravity in the sawing and sorting system  100  may decrease the amount of debris that remains on the unit packages  5 , thereby reducing the cleaning time required.  
         [0055]     After the sawing process, the picker units  31  and  41  pick up the unit packages  5  and move the unit packages  5  to the cleaning units  71  and  72 . The cleaning units  71  and  72  clean and dry the top and bottom surfaces of the unit packages  5  to remove debris and moisture from the unit packages  5 . The cleaning units  71  and  72  are preferably located apart from the other units, thereby preventing the cleaning solution from splashing to the other units.  
         [0056]     After cleaning, the picker units  31  and  41  transfer the unit packages  5  to the sorting tables  81  and  82 . The vision cameras  55  and  57  inspect the unit packages  5  according to the inspection criteria. The sorting transfer robot  85  sorts the unit packages  5  into, for example, the tray  7  for good packages or the tray  8  for faulty packages.  
         [0057]     In the exemplary embodiment of the invention, each of the transfer and sawing robots  30  and  40  may perform separate operations. For example, while the transfer and sawing robot  30  and the sawing spindle units  61  and  62  divide the strip  1  into the unit packages  5 , the transfer and sawing robot  40  cleans and dries the unit packages  5 , transfers the unit packages  5  to the sorting tables  81  and  82 , and then picks up a new strip  1  from the guide rail  21  and performs a subsequent process. Further, while the transfer and sawing robot  40  and the sawing spindle units  61  and  62  divides the strip  1  into the unit packages  5 , the transfer and sawing robot  30  cleans and dries the unit packages  5 , transfers the unit packages  5  to the sorting tables  81  and  82 , and then picks up a new strip  1  from the guide rail  21  and performs a subsequent process. In other words, while one of the transfer and sawing robots  30  and  40  performs a sawing process, the other of the transfer and sawing robots  30  and  40  performs any process other than a sawing process.  
         [0058]     Thus, the exemplary embodiment of the sawing and sorting system combines a sawing apparatus and a sorting apparatus, which may facilitate changes and/or maintenance of a tool and/or parameter.  
         [0059]     The sawing and sorting system comprises a twin blade type sawing spindle unit, thereby reducing the time of the sawing process. The sawing and sorting system may also reduce the amount of the cleaning solution and air used in the cleaning process.  
         [0060]     Further, the sawing and sorting system may reduce the time of a process other than a sawing process and a sorting process. For example, the strip and/or unit package transfer, the cleaning, and the drying processes require reduced time compared with a conventional system. Particularly, the efficiency of the cleaning process may be improved.  
         [0061]     Having described exemplary embodiments of the invention, it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. Therefore, it is to be understood that changes may be made to the embodiments of the invention disclosed that are nevertheless still within the spirit and scope of the invention as defined in the appended claims.