Patent Publication Number: US-2010109652-A1

Title: Apparatus for correcting position of a user tray and a test handler

Description:
BACKGROUND 
     1. Field 
     The present invention relates to a test handler for supplying packaged chips to a tester and classifying tested packaged chips by grades. 
     2. Description 
     A test handler may be used to perform electrical tests on packaged chips at the conclusion of a packaging process. 
     The test handler performs a loading process, a testing process and an unloading process using a test tray including a plurality of containing units capable of containing packaged chips. 
     The test handler transfers the packaged chips to be tested from a user tray to the test tray. This is referred to as a “loading process”. The test handler performs the loading process using a plurality of picker systems. The picker system includes a plurality of nozzles that can absorb the packaged chip. 
     The test handler supplies the test tray containing the packaged chips to a tester. This is referred to as a “testing process”. The tester includes a hi-fix board having a plurality of sockets. The packaged chips in the test tray are brought into contact with the sockets to perform an electrical test on the packaged chips. 
     Further, the test handler includes a chamber system including a plurality of airtight chambers so that the tester performs an electrical test on the packaged chips even under extreme conditions of high temperature or low temperature. 
     The test handler transfers the tested packaged chips from the test tray to a user tray. This is referred to as a “unloading process”. The packaged chips are graded according to the test results, and the handler transfers the graded chips from the test tray to appropriate user tray based on the grading. The test handler performs the unloading process using a plurality of picker systems. 
     The test handler includes a stacker that can store a plurality of user trays used in the loading process and the unloading process. 
       FIG. 1  illustrates a stacker that stores a plurality of user trays in a test handler, and  FIG. 2  illustrates a state where the position of the user tray is corrected. 
     Referring to  FIG. 1 , the stacker  100  can store a plurality of user trays C, and includes a loading stacker  101 , a unloading stacker  102 , a buffer stacker  103  and a transferring unit  104 . 
     A plurality of loading stackers  101  may be installed in the main frame (not shown) of the test handler, and includes a loading stacking member  1011  and a loading plate  1012 . 
     A plurality of user trays C containing packaged chips to be tested may be stored in the loading stacking member  1011 . 
     The loading plate  1012  supports a user tray where the loading process is performed, and is installed in the main frame of the test handler in such a manner that the loading plate  1012  can ascend and descend. 
     A plurality of unloading stackers  102  may be installed in the main frame of the test handler so that a plurality of user trays containing tested packaged chips may be stored in different positions by grades according to the test result. 
     The unloading stacker  102  includes an unloading stacking member  1021  and a unloading plate  1022 . 
     A plurality of user trays C containing tested packaged chips may be stored in the unloading stacking member  1021 . 
     The unloading plate  1022  supports a user tray C where the unloading process is performed, and is installed in the main frame of the test handler in such a manner that the unloading plate  1022  can ascend and descend. 
     A plurality of empty user trays C may be stored in the buffer stacker  103 . 
     The transferring unit  104  can hold the user tray C, and is installed in the main frame of the test handler in such a manner that the transferring unit  104  can move. The transferring unit  104  can be installed in the main frame of the test handler in such a manner that the transferring unit  104  move in X-axis and Y-axis directions. The transferring unit  104  also ascend and descend. 
     In the stacker  100 , the user tray C is transferred as follows. 
     First, the transferring unit  104  transfers the user tray C, which contains the packaged chips to be tested, from the loading stacking member  1011  to the loading plate  1012 . 
     Next, the loading plate  1012  elevates the user tray C, which was transferred from the loading stacking member  1011 , to the position  101   a  where the picker system (not shown) can pick up the packaged chips to be tested in the user tray C. 
     Next, when the user tray C becomes empty by the completion of the loading process, the transferring unit  104  transfers the empty user tray C from the loading plate  1012  to one of the buffer stacker  103  and the unloading plate  1022 . 
     Next, the transferring unit  104  transfers the empty user tray C from one of the buffer stacker  103  and the loading plate  1012  to the unloading plate  1022 . 
     Next, the unloading plate  1022  elevates the user tray C, which was transferred from one of the buffer stacker  103  and the loading plate  1012 , to the position  102   a  where the picker system (not shown) can place tested packaged chips into the use tray C. 
     Next, when the user tray C contains the tested packaged chips by the completion of the unloading process, the transferring unit  104  transfers the user tray C containing the tested packaged chips from the unloading plate  1022  to the unloading stacking member  1021 . 
     The test handler can classify packaged chips by grades by repeatedly performing the above procedure. 
     Referring to  FIGS. 1 and 2 , the stacker  100  should always position the user tray C in the loading plate  1021  and the unloading plate  1022  so that the picker system (not shown) can stably perform the loading process and the unloading process. 
     For this, the stacker  100  includes an apparatus for correcting position of the user tray(not shown) that can move the user tray C to the accurate position in the loading plate  1021  and the unloading plate  1022 . 
     The apparatus for correcting position of the user tray can move the user tray C in X-axis direction and Y-axis direction, thereby positioning the user tray C in the accurate position by the user tray C contacts with a first position member A and a second position member B. 
     However, a conventional apparatus for correcting position of the user tray separately includes a first operating unit for moving the user tray C in X-axis direction and a second operating unit for moving the user tray C in Y-axis direction, thereby making the structure complicated and increasing manufacturing costs. 
     Such problems get worse because a plurality of apparatuses for correcting position of the user tray is installed. 
     BRIEF DESCRIPTION OF THE INVENTION 
     An object of the present invention is to provide an apparatus for correcting position of a user tray and a test handler that has a simple configuration and can move the user tray to the accurate position. 
     The present invention will not be limited to the technical objects described above. Other objects not described herein will be more definitely understood by those in the art from the following detailed description. 
     According to an embodiment of the present invention, there is provided an apparatus for correcting position of a user tray including at least one first position member and at least one second position member that determine position of a user tray, a plate where the user tray is received, a first correcting unit that moves the user tray in a direction where the first position member is installed, a second correcting unit that moves the user tray in a direction where the second position member is installed, and an operating unit that operates the first correcting unit and the second correcting unit. 
     According to an embodiment of the present invention, there is provided a test handler including a loading stacker that a plurality of user trays containing packaged chips to be tested, a loading unit that puts to-be-tested packaged chips in a test tray, a chamber system where the packaged chips are brought into contact with a hi-fix board, an unloading unit that classifies tested packaged chips contained in the test tray by grades according to the test result, an unloading stacker that stores a plurality of user trays containing tested packaged chips, and the apparatus for correcting position of a user tray installed in the loading stacker and the unloading stacker, respectively. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view illustrating a stacker that stores a plurality of user trays in a test handler. 
         FIG. 2  is a plane view illustrating the state where the position of a user tray is corrected. 
         FIG. 3  is a perspective view illustrating an apparatus for correcting position of a user tray according to the present invention and a user tray. 
         FIG. 4  is a perspective view illustrating the lower side of  FIG. 3 . 
         FIG. 5  is a plane view illustrating the state before an apparatus for correcting position of a user tray according to the present invention corrects the position of the user tray. 
         FIG. 6  illustrates the lower side of  FIG. 5 . 
         FIG. 7  is a plane view illustrating the state where an apparatus for correcting position of a user tray according to the present invention has corrected the position of the user tray. 
         FIG. 8  illustrates the lower side of  FIG. 7 . 
         FIG. 9  illustrates the configuration of a test handler according to the present invention. 
         FIG. 10  is a plane view illustrating a test handler according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     An exemplary embodiment of an apparatus for correcting position of a user tray according to the present invention will be described in the following with reference to attached drawings. 
       FIG. 3  is a perspective view illustrating an apparatus for correcting position of a user tray according to the present invention and a user tray.  FIG. 4  is a perspective view illustrating the lower side of  FIG. 3 . 
     Referring to  FIGS. 3 and 4 , an apparatus for correcting position of a user tray  1  includes a first position member  2 , a second position member  3 , a plate  4 , a first correcting unit  5 , a second correcting unit  6 , and an operating unit  7 . 
     The first position member  2  determines a position of a user tray C, and can be installed at one of the plate  4  or the main frame (not shown) of a test handler. 
     The first position member  2  is projected to the upper side of the plate  4  by a certain length so that the first position member  2  can support the first side C 1  of the user tray C. 
     When the first side C 1  of the user tray C is supported by the first position member  2 , the position of the user tray C is corrected in the direction (X arrow direction) where the first position member  2  has been installed. 
     The second position member  3  determines a position of the user tray C, and can be installed at one of the plate  4  or the main frame of the test handler. 
     The second position member  3  is projected to the upper side of the plate  4  by a certain length so that the second position member  3  can support the second side C 2  of the user tray C. 
     When the second side C 2  of the user tray C is supported by the second position member  3 , the position of the user tray C is corrected in the direction (Y arrow direction) where the second position member  3  has been installed. 
     The second position member  3  and the first position member  2  can be installed so that the second position member  3  and the first position member  3  can support the first side C 1  and the second side C 2  that are perpendicular to each other. 
     As such, the apparatus for correcting position of the user tray  1  can move the user tray C to a accurate position by moving the user tray in such a manner that the user tray C is supported by the second position member  3  and the first position member  2 . Moving the user tray C to the accurate position refers to moving the user tray C to a position where the picker system (now shown) can stably perform the loading process and unloading process. 
     The apparatus for correcting position of the user tray  1  may include a plurality of second position members  3  and a plurality of first position members  2 . As such, the user tray C can be moved to a more accurate position. 
     The user tray C can be received in the plate  4 , and the first position member  2  and the second position member  3  can be installed in the plate  4 . The plate  4  can be formed as a tetragonal plate type. 
     The first correcting unit  5  is operated in such a manner that the user tray C can move in the direction (X arrow direction) where the first position member  2  has been installed. The first correcting unit  5  includes a first moving member  51  and a first elastic member  52 . 
     The first moving member  51  is coupled to the plate  4 , and can be rotated on the plate  4 . The first correcting unit  5  includes at least one the first moving member  51 . 
     The first moving member  51  can be coupled in the opposite side of the upper side where the user tray C is received in the plate  4 , that is, in the lower side of the plate  4 . 
     As such, a working area of the picker system (not shown) do not overlap in the first moving member  51 , so the picker system (not shown) can stably perform the loading process and the unloading process. 
     The first moving member  51  includes a first moving frame  511 , a first contacting member  512  and a rotating member  513 . 
     The first moving frame  511  is coupled to the plate  4 . The first moving frame  511  can be rotated around a first shaft  511   a.  The first moving frame  511  can be formed in the form of “&gt;” as a whole, and can be coupled to the lower side of the plate  4 . 
     The first contacting member  512  is coupled to one end  51   b  of the first moving frame  511 , and can move the user tray C according to the rotation of the first moving frame  511 . 
     The first contacting member  512  can be contacted on the third side C 3  of the user tray C. As such, the user tray C can be moved to the direction (X arrow direction) where the first position member  2  has been installed by pushing the third side C 3  of the user tray C. 
     The first contacting member  512  can be formed in such a manner that the first contacting member  512  is projected in the first moving frame  511  so that the first contacting member  512  can contact the third side C 3  of the user tray C received on the upper side of the plate  4 . 
     The first contacting member  512  can be coupled in such a manner that the first contacting member  512  can be rotated at one end  511   b  of the first moving frame  511 . 
     Hence, the first contacting member  512  can rotate around the second shaft  512   a  when moving the user tray C, so the damage by friction of a portion where the first contacting member  512  and the user tray C contact each other can be prevented. 
     The rotating member  513  contacts the operating unit  7 , and can receive force from the operating unit  7  for the first moving frame  511  to be rotated. 
     The rotating member  513  can be coupled to another end  511   c  of the first moving frame  511  in such a manner that the rotating member  513  can be rotated. 
     Hence, the rotating member  513  can rotate around the third shaft  513   a  when the first moving frame  511  is rotated, so the damage by friction of a portion where the rotating member  513  and the operating unit  7  contact each other can be prevented. 
     The first elastic member  52  elastically connects the first moving member  51  to the plate  4 . 
     The first elastic member  52  is installed as many as the number of the first moving member  51 . 
     One side of the first elastic member  52  can be coupled with one end  511   b  of the first moving frame  511 , and the other side of the first elastic member  52  can be coupled with the plate  4 . 
     As such, the first elastic member  52  pulls one end  511   b  of the first moving frame  511  to the plate  4  so that the first moving member  51  can move the user tray C in the direction (X arrow direction) where the first position member  2  has been installed. 
     The second correcting unit  6  is operated in such a manner that the user tray C can move in the direction (Y arrow direction) where the second position member  3  has been installed. The second correcting unit  6  includes the second moving member  61  and the second elastic member  62 . 
     The second moving member  61  can move in the direction (Y arrow direction) where the second position member  3  has been installed, and move the user tray in the direction (Y arrow direction) where the second position member  3  has been installed. 
     The second moving member  61  can be coupled in such a manner that the second moving member  61  can be movable on the plate  4 . If the operating unit  7  is coupled in such a manner that the operating unit  7  can be movable on the plate  4 , the second moving member  61  can be coupled to the operating unit  7 . 
     The second moving member  61  includes a second moving frame  611  and a second contacting member  612 . 
     The second moving frame  611  can move in a hole  41  formed in the plate  4 . The second moving frame  611  can be elastically supported by the second elastic member  62 . The second moving frame  611  is formed in a tetragonal plate type as a whole. 
     The second contacting member  612  is formed in such a manner that the second contacting member  612  can be projected in the second moving frame  611 . The second contacting member  612  can move the user tray C. The second moving member  61  may include at least one or more second contacting member  612 . 
     The second contacting member  612  can contact the fourth side C 4  of the user tray. As such, the user tray C can be moved to the direction where the second position member  3  has been installed by pushing the fourth side C 4  of the user tray C. 
     The second contacting member  612  can be moved in a hole  42  formed on the plate  4 . The second contacting member  612  can be contacted on the fourth side C 4  of the user tray C received on the upper side of the plate  4  by penetrating the hole  42 . 
     The second elastic member  62  elastically supports the second moving member  61 . As such, the second elastic member  62  pushing the second moving member  61  so that the second moving member  61  can move the user tray C in the direction (Y arrow direction) where the second position member  3  has been installed. 
     One side of the second elastic member  62  is supported on the plate, and the other side can support the second moving frame  611 . 
     The second correcting unit  6  can include at least one or more second elastic member  62 . If the second correcting unit  6  include a plurality of second elastic members  62 , the second elastic members  62  can move the second moving member  61  by the same length as a whole by giving constant pressure to the second moving frame  611 . 
     The second elastic member  62  and the first elastic member  52  can be a spring having predetermined elastic force. 
     The first correcting unit  5  and the second correcting unit  6  can move the user tray C in a direction that is perpendicular to each other, respectively. That is, the first correcting unit  5  and the second correcting unit  6  can push the third side C 3  and the fourth side C 4 , which are perpendicular to each other, of user tray C, respectively. 
     The operating unit  7  can operate the first correcting unit  5  and the second correcting unit  6 . As such, the first correcting unit  5  and the second correcting unit  6  can move the user tray C to the accurate position. 
     Hence, the apparatus for correcting position of the user tray  1  can operate the first correcting unit  5  and the second correcting unit  6  by one operating unit  7 , so the apparatus is made of a simple structure, and can move the user tray C to the accurate position. 
     Further, the apparatus for correcting position of the user tray  1  can move the user tray C to the accurate position using only one power source, thereby reducing manufacturing costs and maintenance costs. 
     The operating unit  7  is coupled to the plate  4 , and is movable on the plate  4 . As the operating unit  7  is moved on the plate  4 , the first correcting unit  5  and the second correcting unit  6  can be operated. 
     The operating unit  7  can be coupled to the lower side of the plate  4 . 
     The operating unit  7  may include one among a guide block and a guide rail, and the plate  4  may include the other. 
     The operating unit  7  can be coupled to a rod  8   a  of a cylinder  8 , and can be movable on the plate  4  as the rod  8   a  of the cylinder  8  moves. 
     The cylinder may be a pneumatic cylinder or a hydraulic cylinder. 
     The operating unit  7  may include a first operating unit  71  and a second operating unit  72 . 
     The first operating unit  71  can be coupled to the plate  4 , and can be movable on the plate  4 . and the first operation unit  71  can operate the first correcting unit  5 . 
     The first operating unit  71  operates the first correcting unit  5  so that the second operating unit  72  can operate the second correcting unit  6 . 
     The first operating unit  71  can be coupled to the lower side of the plate  4 . The first operating unit  71  includes one among a guide block and a guide rail, and the plate  4  can include the other. 
     The first operating unit  71  includes at least one or more protruding member  711  that rotates the first moving member  51 . 
     The protruding member  711  is projected in the operating plate  71   a  of the first operating unit  71 . The protruding member  711  can be projected in the direction where the first moving member  51  is positioned. 
     As such, when the rotating member  513  is supported by the protruding member  711 , the first moving member  51  can be rotated in a direction where the first contacting member  512  goes away from the plate  4 . 
     When the rotating member  513  is supported by the portion where the protruding member  711  is not formed in the operating plate  71   a,  the first moving member  511  can be rotated in the direction where the first contacting member  512  comes to contact the third side C 3  of the user tray C. 
     The first moving member  51  can be elastically connected to the plate  4  by the first elastic member  52 . The first elastic member  52  is stretched when the rotating member  513  is supported on the protruding member  711 . The first elastic member  52  is compressed when the rotating member  513  is supported on a portion where the protruding member  711  is not formed in the operating plate  71   a.  As such, the first moving member  51  can be rotated. 
     Hence, the first moving member  51  can move the user tray C so that the first side C 1  of the user tray is supported on the first position member  2  by the elastic force of the first elastic member  52 , so the damage of the user tray C by excessive force given to the user tray C can be prevented. 
     The second operating unit  72  is coupled to the plate  4 , can be movable on the plate  4 . The second operating unit  72  can operate the second correcting unit  6 , being interlocked with the first operating unit  71 . 
     The second operating unit  72  can be coupled to the lower side of the plate  4 . The second operating unit  72  can include one among a guide block or a guide rail, and the plate  4  can include the other. 
     The second operating unit  72  move the second moving member  61 , being interlocked with the first operating unit  71 . 
     The second operating unit  72  can move the second moving member  61  in the direction (the opposite direction of Y arrow) that goes away from the second position member  3 . The second operating unit  72  can move the second moving member  61  in the direction (Y arrow direction) where the second position member  3  has been installed. 
     The second operating unit  72  can move the second moving member  61  in the direction (the opposite direction of Y arrow) that goes away from the second position member  3  by pushing the second moving member  61 . The second operating unit  72  can move the second moving member  61  in the direction (Y arrow direction) where the second position member  3  has been installed by removing the force that has pushed the second moving member  61 . 
     The second moving member  61  can be elastically supported by the second elastic member  62 . The second elastic member  62  is compressed when the second operating unit  72  gives force to the second moving member  61 , and is stretched by elastic force when the force is removed. As such, the second moving member  61  can be movable. 
     Hence, the second moving member  61  can move the user tray C so that the second side C 2  of the user tray C is supported on the second position member  3  by elastic force of the second elastic member  62 , so the damage of the user tray C by excessive force given to the user tray C can be prevented. 
     The first operating unit  71  and the second operating unit  72  can be integrally formed, so when the first operating unit  71  is moved as the load  8   a  of the cylinder  8  is moved, the second operating unit  72  can also be moved together. 
     However, the user tray C can be received on the plate  4  in such a manner that the user tray C is separated from the second position member  3  and the first position member  2  by respective distances. 
     Here, in order to more efficiently move the user tray C to the accurate position, the first operating unit  71  and the second operating unit  72  can be separated from each other as the first operating unit  71  and second operating unit  72  is moved on the plate  4 . 
     As the first operating unit  71  is moved on the plate  4 , the second operating unit  72  can operate the second correcting unit  6 . 
     The first operating unit  71  can move the second operating unit  72  by giving force to the second operating unit  71  as being moved on the plate  4 , can move the second operating unit  72  by removing the force. 
     Specifically, when the first operating unit  71  is moved in the direction where the second operating unit  72  has been positioned, the first operating unit  71  can push and move the second operating unit  72 . when the first operating unit  71  is moved in the opposite of the direction where the second operating unit  72  has been positioned, the second operating unit  72  can move by the second elastic member  62 . 
     The movement of the second operating unit  72  stops when the second side C 2  of the user tray C is supported on the second position member  3 . The first operating unit  71  continues to move until the first side C 1  of the user tray C is supported on the first position member  2 , so the first operating unit  71  continues to move after the first operating unit  71  and the second operating unit  72  is separated each other. 
     That is, the first operating unit  71  and the second operating unit  72  can be moved by different distances. As such, the first moving member  51  and the second moving member  61  can move the user tray C by different distances, thereby efficiently moving the user tray C to the accurate position. 
     As such, even though the user tray C is separated from the first position member  2  and the second position member  3  by different distances, when the user tray C is received on the plate  4 , the apparatus for correcting position of the user tray  1  can move the user tray C to the accurate position. 
     Further, even though the size of the user tray C is changed within a certain range by the change of the type of the packaged chips, the apparatus for correcting position of the user tray  1  can move the changed user tray C to the accurate position without re-manipulation. 
     Hereinafter, the operation in the case where the first operating unit  71  and the second operating unit  72  are coupled to the plate  4 , and can be separated from each other while moving on the plate  4  will be described with reference to the attached drawings. 
       FIG. 5  is a plane view illustrating the state before an apparatus for correcting position of a user tray according to the present invention corrects the position of the user tray.  FIG. 6  illustrates the lower side of  FIG. 5 .  FIG. 7  is a plane view illustrating the state where an apparatus for correcting position of a user tray according to the present invention has corrected the position of the user tray.  FIG. 8  illustrates the lower side of  FIG. 7 . 
     Referring to  FIGS. 5 and 6 , when the first operating unit  71  is moved in the direction where the second operating unit  72  is positioned, the first moving member  51  is rotated in a direction where the first contacting member  512  goes away from the plate  4  as the rotating member  513  is supported on the protruding member  711  of the first operating unit  71 . Here, the first elastic member  52  is stretched. 
     The first operating unit  71  pushes the second operating unit  72 , and the second operating unit  72  moves the second moving member  61  in a direction (the opposite direction of Y arrow) where the second contacting member  612  goes away from the second position member  3 . Here, the second elastic member  62  is compressed. 
     In such a state, the user tray C can be received on the plate  4  without being disturbed by the first moving member  51  and the second moving member  61 . 
     Referring to  FIGS. 7 and 8 , in the state where the user tray C is received on the plate  4 , when the first operating unit  71  moves in the opposite of the direction where the second operating unit is positioned, the rotating member  51  is supported on the portion where the protruding member  711  has not been formed in the first operating unit  71 . As such, the first moving member  51  is rotated in a direction where the first contacting member  512  comes to contact the third side C 3  of the user tray C. Here, the first elastic member  52  is restored to the original form as the first elastic member  52  is compressed by elastic force. 
     As such, the user tray C is moved in a direction where the first position member  2  has been installed by the push of the first contacting member  512 . The movement of the user tray C stops when the user tray C is supported on the first position member  2 . 
     The second operating unit  72  removes the force that has been given to the second moving member  61  as the force that has been given to the first operating unit  71  is removed. 
     As such, the second moving member  61  is moved in a direction where the second position member  3  has been installed, and the second contacting member  612  moves the user tray C in a direction where the second position member  3  has been installed by pushing the fourth side C 4  of the user tray C. Here, the second elastic member  62  is restored to the original form as the second elastic member  62  is stretched by elastic force. 
     The movement of the user tray C stops when the user tray C is supported on the second position member  3  by the push of the second contacting member  612 . 
     When the user tray C is supported on the second position member  3 , the movement of the second moving member  61  and the second operating unit  72  stops. And, the first operating unit  71  continues to move until the user tray C is supported on the first position member  2 , so the first operating unit  71  and the second operating unit  72  become separated from each other. 
     The first side C 1 , the second side C 2 , the third side C 3  and the fourth side C 4  of the user tray C are supported on the first position member  2 , the second position member  3 , the first moving member  51  and the second moving member  61 , respectively, so the position of the user tray C is corrected to a position where the picker system can be stably perform the loading process and unloading process. 
     Hereinafter, an exemplary embodiment of a test handler according to the present invention including the above-described apparatus for correcting position of a user tray will be described in detail with reference to the attached drawings. 
       FIG. 9  is a block diagram illustrating the configuration of a test handler according to the present invention. 
     Referring to  FIGS. 1 to 9 , a test handler  10  according to the present invention includes a chamber system  11 , a loading stacker  12 , a unloading stacker  13 , a loading unit  14 , an unloading unit  15  and a buffer unit  16 . 
     The chamber system  11  includes a first chamber  111 , a second chamber  112  and a third chamber  113 . 
     Within the first chamber  111 , the packaged chips to be tested, contained in the test trays T, are heated or cooled to a testing temperature, which is predetermined depending upon a user&#39;s quality requirements. The test tray T is moved forward by a specific distance within the first chamber  111  as the heating or cooling occurs. After the packaged chips are heated or cooled to a testing temperature, a test tray T is transferred from the first chamber  111  into the second chamber  112 . 
     Within the second chamber  112 , the packaged chips in the test tray T are brought into contact with sockets of a hi-fix board H to receive the electrical tests. The test board H is coupled to the second chamber  112 . After the packaged chips are all tested by a tester, the test tray T is transferred from the second chamber  112  into the third chamber  113 . 
     Within the third chamber  113 , the tested packaged chips contained in the test tray T are cooled or heated to room temperature. The test trays T are moved forward by a specific distance with the third chamber  113  as the heating or cooling occurs. After the packaged chips are cooled or heated to room temperature, the test tray T is transferred from the third chamber  113  to the unloading unit  15 . 
     The first, second, and third chambers  111 ,  112 , and  113  may be arranged in a row in the horizontal direction, in this order. In this arrangement, a plurality of the second chambers  112  may be provided in a column. In other words, one second chamber  112  may be located over another second chamber  112 . 
     The first, second, and third chambers  111 ,  112 , and  113  may also be arranged in a column in the vertical direction, in this order, with the second chamber  112  in between. 
     The loading stacker  12  stores a plurality of user trays C containing packaged chips to be tested. The apparatus for correcting position of the user tray  1  is installed in the loading stacker  12 . 
     The unloading stacker  13  stores a plurality of user trays containing tested packaged chips. The apparatus for correcting position of the user tray  1  is installed in the unloading stacker  13 . The tested packaged chips are received in the user trays C positioned in different positions by grades. 
     The loading unit  14  puts the packaged chips to be tested in the test tray, and includes a loading picker  141 . 
     The loading picker  141  moves in X-axis and Y-axis directions. The loading picker  141  also ascend and descend. The loading picker  141  includes a plurality of nozzles that can absorb packaged chips. 
     The loading picker  141  picks up packaged chips to be tested from the user tray C positioned in the loading stacker  12 , and puts the chips in the test tray positioned in the loading position  14   a,  which is the loading process. 
     The test handler  10  may include a plurality of the loading pickers  141  so that time that takes in the loading process may be reduced. 
     The loading-process-completed test tray is transferred from the loading position  14 a to the first chamber  111 . 
     The unloading unit  15  classifies tested packaged chips contained in the test tray by grades according to the test result. The unloading unit  15  includes an unloading picker  151 . 
     The unloading picker  151  moves in X-axis and Y-axis directions. The unloading picker  151  also ascend and descend. The unloading picker  151  includes a plurality of nozzles that can absorb packaged chips. 
     The unloading picker  151  separates tested packaged chips from the test tray positioned in the unloading position  15   a,  and puts the separated packaged chips in the user tray C positioned in the unloading stacker  13  which is the unloading process. 
     The unloading picker  151  can put tested packaged chips in the user trays C positioned in different positions by grades according to the test result. 
     The test handler  10  can include a plurality of the unloading pickers  151  so that time that takes in the unloading process may be reduced. 
     The test tray that gets empty by the completion of the unloading process is transferred from the unloading position  15   a  to the loading position  14   a.    
     The buffer unit  16  can temporarily contain packaged chips. 
     The buffer unit  16  may be installed to be used in at least one of the loading process and the unloading process. 
     If the buffer unit  16  is installed to be used in the loading process, the loading picker  141  can pick up packaged chips to be tested from the user tray C positioned in the loading stacker  12 , and can put the packaged chips to be tested in the test tray positioned in the loading position via the buffer unit  16 . 
     If the buffer unit  16  is installed to be used in the unloading process, the unloading picker  151  can separate tested packaged chips from the test tray positioned in the unloading position  15   a,  and can put the tested packaged chips in the user tray C positioned in the unloading stacker  13  via the buffer unit  16 . 
     Hereinafter, another embodiment of a test handler that is constituted as described above will be described in detail with reference to the attached drawings. 
     Here, a test handler according to another embodiment has the configuration similar to that of the above-described test handler, so only differences in the configuration will be described in the following. 
       FIG. 10  is a plane view illustrating a test handler according to another embodiment of the present invention. 
     Referring to  FIGS. 9 and 10 , a test handler  10  according to another embodiment of the present invention includes an exchanging unit  17  that is not included in the test handler  10  of  FIG. 9 . 
     The exchanging unit  17  exchanges a test tray T containing packaged chips to be tested and a test tray T containing tested packaged chips with the chamber system  11 . 
     The test tray T containing packaged chips to be tested is transferred from the exchanging unit  17  to the chamber system  11 , and the test tray T containing tested packaged chips is transferred from the chamber system  11  to the exchanging unit  17 . 
     In the exchanging unit  17 , the process of putting packaged chips to be tested in the test tray T and the process of separating tested packaged chips from the test tray T are performed. Here, the process of putting packaged chips to be tested in the test tray T is part of the loading process, and the process of separating the tested packaged chips from the test tray T is part of the unloading process. The exchanging unit  17  includes the loading position  14 a and the unloading position  15   a,  and implements the loading position  14 a and unloading position in one position. 
     The exchanging unit  17  may further include a rotating unit  171 . 
     The rotating unit  171  rotates a test tray containing the packaged chips to be tested from a horizontal position to a vertical or upright position. 
     The test tray T remains in the upright position during its transfer within the chamber system  11 . 
     The rotating unit  161  may rotate an upright-positioned test tray containing tested packaged chips from a vertical position to a horizontal position. The test tray T remains in the horizontal position while the tested packaged chips are separated from it and then the new packaged chips to be tested are received into it. 
     It should be understood by those of ordinary skill in the art that various replacements, modifications and changes may be made in the form and details without departing from the spirit and scope of the present invention as defined by the following claims. Therefore, it is to be appreciated that the above described embodiments are for purposes of illustration only and are not to be construed as limitations of the invention.