Abstract:
A technology related to a pick-and-place apparatus for electronic device inspection equipment is provided. The pick-and-place apparatus includes the guiding unit that can interact with a loading element and can guide the picker to load the electronic devices at a correct position on the loading element. Therefore, the pick-and-place apparatus can allow the electronic devices, for example, semiconductor devices having a ball type of electrical contact lead (BGA, FBGA, etc.), to electrically contact the tester in a stable manner when the tester inspects the electronic devices.

Description:
PRIORITY 
     This application claims the benefit under 35 U.S.C. §119(a) of a Korean patent application filed on Jul. 13, 2009 in the Korean Intellectual Property Office and assigned Serial No. 10-2009-0063752, the entire disclosure of which is hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to test handlers. More particularly, the present invention relates to a technology that can be applied to carrier boards for loading semiconductor devices having a ball type of electrical contact lead (BGA, FBGA, etc.), in a pick-and-place apparatus for electronic device inspection equipment. 
     2. Description of the Related Art 
     Electronic devices such as, semiconductor devices are tested via a tester, when a test handler makes them electrically contact the tester. 
     Test handlers are closely related to technology involving electrical contact precision between electronic devices and the tester, temperature controllability, and an electronic device moving method. Of them, electrical contact precision is the most important factor. The present invention is related to how to guarantee electrical contact precision. 
     Semiconductor devices are electronic devices and their electrical contact leads are divided into a type of wire, for example, TSOP, SOP, TQFP, QFP, etc., and a type of ball, for example, BGA, FBGA, etc. It is very important that the electrical contact leads of the semiconductor device precisely contact the tester, irrespective of their type. 
     In particular, a semiconductor device having a ball type electrical contact lead exquisitely aligns a plurality of electrical contact leads on its underside, so the electrical contact leads may not electrically contact the tester if the semiconductor device is even slightly misaligned. 
     In general, test handlers transfer semiconductor devices via a carrier board (also called a test tray, a test board, or the like) and also allow the semiconductor devices loaded on the carrier board to electrically contact the tester. 
     A carrier board includes a plurality of inserts (also called a carrier, a carrier module, etc.) aligned in a matrix form. An insert loads one or more semiconductor devices thereon. A technology related to a carrier board and an insert was disclosed in Korean Patent Publication No. 10-2005-0009066 entitled “carrier module for semiconductor device test handlers,” which is hereinafter referred to as a “well-known technology.” This publication discloses the insert in which a BGA chip can be properly placed. 
       FIG. 1  is a view illustrating a conventional insert that loads semiconductor devices with BGA type electrical contact leads. 
     Referring to  FIG. 1 , the conventional insert forms a placement compartment  111  that corresponds in size to a semiconductor device in a loaded part  110  on which a semiconductor device is loaded. The bottom side of the placement compartment  111  is perforated so that the ball type of electrical contact leads of the placed semiconductor device can be electrically contacted with the tester. 
     In addition, the placement compartment  111  also forms grooves, corresponding to the shape and spacing of the balls of the semiconductor device, on the inner wall of the perforated bottom side thereof. 
     When a semiconductor device is appropriately placed in the placement compartment, the balls of the semiconductor device are inserted into the grooves of the placement compartment, so that the semiconductor device can be stably loaded on the loaded part  110 . 
     Meanwhile, since the semiconductor devices loaded in the carrier board are electrically contacted with a tester, the test handler is equipped with a pick-and-place apparatus that can load semiconductor devices from a customer tray onto a carrier board or unload semiconductor devices from a carrier board onto a customer tray. 
     The pick-and-place apparatus includes a plurality of picking apparatuses each of which can pick and place one semiconductor device. 
     In general, a picking apparatus includes a picker that sucks and picks a semiconductor device according to vacuum pressure or places it by releasing the vacuum pressure. 
     The following description describes the transfer and loading methods of semiconductor devices in a conventional picking apparatus. 
     The picking apparatus sucks and picks semiconductor devices from a loading element A (which may be a customer tray, a buffer, an aligner, a carrier board, etc.) and is then moved up over a loading element B (which may be a customer tray, a buffer, an aligner, a carrier board, etc.). When the pick-and-place apparatus moves, the picking apparatuses are also moved. The pick-and-place apparatus is lowered a certain distance above the loading element B and then places the semiconductor devices thereon, so that the semiconductor devices can be dropped and loaded on the loading element B. 
     However, semiconductor devices with a ball type of electrical contact leads have a relatively narrow spacing between their electrical contact leads, so they can be easily misaligned in the carrier board due to an impact when the semiconductor devices are dropped or an impact accompanying an operation where the apparatuses hold the semiconductor devices. In that case, the semiconductor devices cannot be electrically contacted with the tester, which causes test failure. 
     SUMMARY OF THE INVENTION 
     An aspect of the present invention is to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a pick-and-place apparatus that can load semiconductor devices on a loading element, without causing an impact when the semiconductor devices are placed, and irrespective of an impact accompanying the operation of a holding apparatus. 
     In accordance with an aspect of the present invention, an apparatus for electronic device inspection equipment is provided. The apparatus includes a plurality of picking apparatuses that pick up electronic devices loaded on one loading element (A), move the electronic devices, and unloads the electronic devices onto another loading element (B), and a module-forming block that joins the plurality of picking apparatuses in one module. At least one picking apparatus includes: a body fixed to the module-forming block, a picker having a picking unit, coupled to the body, for picking up an electronic device or releasing the picked electronic device, and a guiding unit for interacting with another loading element (B) and for guiding the picker to load the electronic devices at a correct position on another loading element (B). 
     Preferably, the guiding unit comprises a guiding member having position setting pins, joined to the body, for setting positions between the picker and another loading element (B) by being inserted into position setting holes formed in another loading element (B). 
     Preferably, the guiding member is joined to the body so that it can be relatively moved within a preset range of movement distance with respect to the body in the direction of another loading element (B) or opposite thereto. The guiding unit further includes an elastic member (C) exerting an elastic force on the guiding member toward another loading element (B). 
     Preferably, at least one picking apparatus further includes another elastic member (D) for maintaining an elastic force with respect to the module-forming block, another elastic member being joined so that it can be relatively moved within a preset range of movement distance with respect to the module-forming block in the direction toward another loading element (B) or opposite thereto. Another elastic member (D) has a greater elastic coefficient than the one elastic member (C) does. 
     Preferably, at least one picking apparatus further includes another elastic member (D) for maintaining an elastic force with respect to the module-forming block. Another elastic member is joined so that it can be relatively moved within a preset range of movement distance with respect to the module-forming block in the direction toward another loading element (B) or in the opposite direction thereto. 
     Preferably, the pick-and-place apparatus may further include coupling pins with a head and a coupling part for coupling at least one picking apparatus to the module-forming block, in which the coupling part forms a thread on at least one end portion thereof. The module-forming block forms coupling through-holes for coupling at least one picking apparatus therewith, and the body forms a threaded hole into which the coupling part of the coupling pin passing through the coupling through-hole is screwed. 
     Preferably, the coupling part has an external diameter smaller than its internal diameter of coupling through-hole. 
     Preferably, the picking apparatus is coupled to the module-forming block in a certain range of angle with respect to a straight line passing through the module-forming block, the picking apparatus, and another loading element (B). 
     In accordance with another aspect of the present invention, an apparatus of a pick-and-place apparatus for electronic device inspection equipment is provided. The apparatus includes: a body fixed to a module-forming block of the pick-and-place apparatus, a picker having a picking unit, coupled to the body, for picking up an electronic device or releasing the picked electronic device, and a guiding unit for interacting with a loading element and for guiding the picker to load the electronic devices at a correct position on the loading element. 
     Preferably, the guiding unit comprises a guiding member having position setting pins, joined to the body, for setting positions between the picker and the loading element by being inserted into position setting holes formed in the loading element. 
     Preferably, the guiding members include a plurality of position setting pins. 
     Preferably, the position setting pin is formed in such a way that its one end protrudes more toward the loading element than one end of the picking unit of the picker, so that the position pin can first set a position between the picker and the loading element before the semiconductor device, picked up by the picking unit, is placed in a carrier board. 
     Preferably, the guiding member is joined to the body so that it can be relatively moved within a preset range of movement distance with respect to the body in the direction of the loading element or opposite thereto. The guiding unit further includes an elastic member exerting an elastic force on the guiding member toward the loading element. 
     In accordance with still another aspect of the present invention, an aligner for inspection equipment of electronic devices is provided. The aligner is formed with a plurality of aligning grooves in which semiconductor devices are aligned and placed and pin receiving walls that are protrudent at both sides of the aligning groove. The pin receiving walls form pin receiving holes into which position setting pins of a pick-and-place apparatus are inserted. 
     In accordance with yet another aspect of the present invention, a method for loading electronic devices onto a loading element in electronic device inspection equipment is provided. The method includes: releasing a holding state of a holding apparatus installed to a loading element on which electronic devices are loaded, moving the pick-and-place apparatus toward the loading element and setting a position between the loading element and a picker that picks up an electronic device, placing the electronic device, picked up by the picker, in the loading element and holding the placed electronic device, releasing the picking state of the picker, and moving the pick-and-place apparatus in the direction opposite to the loading element. 
     Preferably, placing the electronic device and holding the placed electronic device includes: placing the electronic device, picked up by the picker, in the loading element, moving additionally the picker by a distance corresponding to a distance by which the loading element is retroceded in the same direction as the pick-and-place apparatus moves, so that the electronic device can remain in the loading element, and holding the electronic device. 
     Preferably, the method may further include loading different electronic devices on the loading element, only if the different electronic devices have the same type and position of electrical contact lead as the electronic devices. 
     Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a view illustrating a conventional insert that loads semiconductor devices with BGA type electrical contact leads; 
         FIG. 2  is a perspective view illustrating a pick-and-place apparatus according to an embodiment of the present invention; 
         FIG. 3  is a perspective view illustrating a picking apparatus applied to the pick-and-place apparatus of  FIG. 2  according to an exemplary embodiment of the present invention; 
         FIG. 4  is a front view of the picking apparatus of  FIG. 3  according to an exemplary embodiment of the present invention; 
         FIGS. 5A to 5D  are views illustrating an insert corresponding to the picking apparatus of  FIG. 3  according to an exemplary embodiment of the present invention; 
         FIG. 6  and  FIG. 7  are views that describe a coupling state of the pick-and-place apparatus of  FIG. 2  according to an exemplary embodiment of the present invention; 
         FIG. 8  to  FIG. 18  are views that describe the operation of the pick-and-place apparatus according to an exemplary embodiment of the present invention; 
         FIG. 19  is a view illustrating an aligner adapted to the pick-and-place apparatus according to an exemplary embodiment of the present invention; and 
         FIG. 20  and  FIG. 21  are cross-sectional views that describe a method where the pick-and-place apparatus picks up semiconductor devices from the aligner, according to an exemplary embodiment of the present invention. 
     
    
    
     Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. 
     BRIEF DESCRIPTION OF SYMBOLS IN THE DRAWINGS 
     
         
         
           
               200 : pick-and-place apparatus 
               210 : picking apparatus 
               211 : body 
               211   a : threaded hole 
               212 : picker 
               212   a : holding unit 
               213 : guiding unit 
               213   a : guiding member 
               213   a - 1 ,  213   a - 2 : position setting pin 
               213   b - 1 ,  213   b - 2 : spring 
               214   a ,  214   b : elastic member 
               220 : module-forming block 
               221 : coupling through-hole 
               230 : coupling pin 
               231 : head 
               232 : coupling part 
               232   a : thread 
           
         
       
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness. 
     The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. 
     It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces. 
       FIG. 2  is a perspective view illustrating a pick-and-place apparatus  200  according to an exemplary embodiment of the present invention. 
     Referring to  FIG. 2 , the pick-and-place apparatus  200  includes  16  picking apparatuses  210 , a module-forming block  220 , and coupling pins  230 . 
     As shown in  FIG. 3 , each of the picking apparatuses  210  includes a body  211 , a picker  212 , a guiding unit  213 , and a pair of elastic members  214   a  and  214   b.    
     The body  211  is shaped as the letter ‘L’ viewed from the side. The body  211  is joined to the module-forming block  220  using coupling pins  230 , so that the body  211  can move up and down, with being close to or far from the module-forming block  220  in a certain range of movement distance. The body  211  can be moved in one direction, i.e., toward a carrier board, and in the opposite direction thereto, i.e., toward the module-forming block  220 . The body  211  forms threaded holes  211   a  for receiving the coupling pins  230  on its upper side. The body  211  includes a pair of guide bars  211   b - 1  and  211   b - 2  on the upper side, located at both opposite sides with respect to the threaded hole  211   a , so that the guide bars  211   b - 1  and  211   b - 2  can guide the vertical movement of the body or prevent unintentional rotation of the picking apparatus  210 . The body  211  is further cut off at its both sides, viewed from the front, and allows an LM guider  211   c  to be located at the cut-off portions. The LM guider  211   c  guides the vertical movement of a guiding member. 
     The picker  212  is joined with the body  211 . The picker  212  includes a picking unit  212   a  for picking or releasing a semiconductor device at its lower end. The picking unit  212   a  is made of a flexible material. 
     The guiding unit  213  is located at the cut-off portions of the body  211 . The guiding unit  213  is interacted with an insert of a carrier board and guides the picker  212  so that it can load a semiconductor device at a precise position in the carrier board. 
     The guiding unit  213  includes a guiding member  213   a  and a pair of springs  213   b - 1  and  213   b - 2 . 
     The guiding unit  213  is shaped as the letter T viewed from the front. The guiding unit  213  is joined to the body  211 , so that the guiding unit  213  can be guided by the LM guider  211   c  and thus be moved up and down with respect to the body  211  in a preset movement distance. The guiding unit  213  can be moved in one direction, i.e., toward a carrier board, and in an opposite direction thereto, i.e., toward the module-forming block  220 . The guiding unit  213  further forms a stopper STP, shaped as the letter ‘L’ viewed from below, at its lower portion. While the body  211  is being lowered in a state where the lower surface of the stopper STP contacts the upper surface of the insert, the stopper STP serves to prevent the body  211  from being lowered after it has been lowered a certain distance, which will be explained in detail later. 
     The L-shaped stopper STP forms position setting pins  213   a - 1  and  213   a - 2  at both opposite ends of the letter ‘L’ on its lower surface, where the positions of the position setting pins  213   a - 1  and  213   a - 2  correspond to those of position setting holes that are formed on the diagonal line in the insert, which will be described in detail later. 
     As shown in  FIG. 5A  (a perspective view illustrating an insert) and  FIG. 5B  (a top view illustrating the insert of  FIG. 5A ), the diameters and the spacing distance between the position setting pins  213   a - 1  and  213   a - 2  correspond to those of the position setting holes  511   a  and  511   b  of the insert  510 , respectively. The position setting pins  213   a - 1  and  213   a - 2  are shaped as a circular cone at their end portion so the peak of the cone can allow the position setting pins  213   a - 1  and  213   a - 2  to be easily inserted into the position setting holes  511   a  and  511   b  although the centers between the position setting pins  213   a - 1  and  213   a - 2  and the position setting holes  511   a  and  511   b  are not completely aligned with each other. In addition, as shown in  FIG. 4 , the lower ends of the position setting pins  213   a - 1  and  213   a - 2  are protruded toward the carrier board by a length that is a longer than the lower end of the holding unit  212   a  of the picker  212 . This is because the picker  212  and the carrier board, i.e., the picker  212  and the insert  510 , can set their position first before the semiconductor device picked by the holding unit  212   a  is placed in the carrier board. 
     Referring to  FIGS. 5A and 5B , the bottom side of the placement compartment  512  of the insert  510  is perforated. The inner wall around the perforated bottom side forms grooves  512   a  that are arranged, matching the shape and spacing of the balls of the semiconductor device. The area of the bottom side of the placement compartment  512  is much greater than the total area occupied by the balls of a semiconductor device, so that the insert can receive various sizes of semiconductor devices only if the position of their balls is standardized. For example, as shown in  FIGS. 5C and 5D , although semiconductor devices D 1  and D 2  have different areas S 1 ×L 1  and S 1 ×L 1 , respectively, they can be placed in the same insert  510  only if the position and shape of the ball  1   b , serving as an electrical contact lead, are standardized. 
     In an embodiment of the present invention as shown in  FIGS. 5C and 5D , although the balls of a semiconductor device are inserted into all the grooves  512   a  formed in the bottom side of the placement compartment  512 , it should be understood that the present invention is not limited to the embodiment. For example, if different semiconductor devices have the same sized balls spaced apart with the same spacing, they can be placed in the placement compartment  512  as the balls of each of the semiconductor devices are inserted into the grooves  512   a  formed in at least only one side of the bottom side of the placement compartment  512 . Therefore, this structure enlarges the universality of the insert  510 . 
     As shown in  FIGS. 5A and 5B , holding apparatuses  513   a  and  513   b  hold a semiconductor device placed in the placement compartment  512 . 
     Referring back to  FIG. 3 , the pair of springs  213   b - 1  and  213   b - 2  are placed between the guiding member  213   a  and the lower surface of the upper portion of the body  211 . The pair of springs  213   b - 1  and  213   b - 2  exert an elastic force to the guiding member  213   a  in the lower direction (i.e., in the direction toward the carrier board). 
     The pair of elastic members  214   a  and  214   b  are configured to contain guide bars  211   b - 1  and  211   b - 2  inserted thereinto, respectively. The pair of elastic members  214   a  and  214   b  exert an elastic force in lower direction (i.e., in the direction toward the carrier board) by an elastic repulsive force between the module-forming block  220  and the picking apparatus  210 . In an embodiment of the present invention, the pair of elastic members  214   a  and  214   b  are implemented with a coil spring. The pair of elastic members  214   a  and  214   b  have a much greater elastic coefficient than that of the pair of springs  213   b - 1  and  213   b - 2 . 
     The following description explains the function of the stopper STP with reference to  FIG. 6 . 
     As shown in  FIG. 6 , if the lower surface of the stopper STP contacts the upper surface of the insert  510 , the position setting pins  213   a - 1  and  213   a - 2  cannot further enter the position setting holes  511   a  and  511   b . As such, at the time that the lower surface of the stopper STP contacts the upper surface of the insert  510 , it is preferable that the interval a 1  between the upper surface of the stopper STP and the lower surface of the body  211  is equal to or a little greater than the interval a 2  between the placement surface of the insert  510  and the lower surface of the semiconductor device picked by the picker  212 . 
     Referring to  FIG. 7 , after the lower surface of the stopper STP contacts the upper surface of the insert  510 , the guiding member  213   a  cannot be further lowered by the stopper STP although the pick-and-place apparatus  200  continues to be lowered. Therefore, only the body  211  is lowered, by compressing the pair of springs  213   b - 1  and  213   b - 2 . 
     If the lower surface of the body  211  being lowered contacts the upper surface of the stopper STP as shown in  FIG. 7 , the lowering operation of the body  211  is stopped. In this state, the continued lowering operation of the pick-and-place apparatus  200  causes the compression of the pair of elastic members  214   a  and  214   b.    
     The module-forming block  220  serves to join 16 picking apparatuses  210  in one module. To this end, as shown in  FIG. 8 , the module-forming block  220  forms  16  coupling through-holes  221  in a vertical direction. 
     The module-forming block  220  also forms guiding holes  222   a  and  222   b , through which the guide bars  211   b - 1  and  211   b - 2  pass, at both sides of each coupling through-hole  221 . 
     Referring to  FIG. 8 , the coupling pins  230  is formed with a head  221  and a coupling part  232 . The coupling part  232  forms a thread on its lower portion. The coupling pins  230  pass through the coupling through-hole  221  and its lower portion is screwed into the threaded hole  211   a  of the body  211 , thereby joining the picking apparatus  210  with the module-forming block  220 . It is preferable that the external diameter b of the coupling part  232  is smaller than the internal diameter c of the coupling through-hole  221 , i.e., b&lt;c. This allows the picking apparatus  210  to be coupled to the module-forming block  220  with a flexible movement margin that is within range of angle θ with respect to the perpendicular line L passing the center of the module-forming block  220  toward the carrier board. Therefore, although the position setting pins  213   a - 1  and  213   a - 2  are not completely consistent with the center of the position setting holes  511  and  512 , respectively, they can be smoothly inserted into the position setting holes  511  and  512 . 
     If the internal diameter c of the coupling through-holes  221  is much smaller than the external diameter b of the coupling part  232 , the clearance of the picking apparatus  210  is increased. It is preferable that the difference between the internal diameter c of the coupling through-hole  221  and the external diameter b of the coupling part  232  is 0.1˜0.05 mm, experimentally. It should be understood that the difference between the internal diameter c of the coupling through-hole  221  and the external diameter b of the coupling part  232  may differ according to the vertical length of the pick-and-place apparatus or the length of the coupling pin. 
     The following description explains the operation of the pick-and-place apparatus  200 , based on one picking apparatus  210 , with reference to  FIGS. 10 to 18 . 
     1. Pick and Move Semiconductor Devices (Refer to  FIG. 10 ) 
     The pick-and-place apparatus  200  sucks and picks up semiconductor devices D from a loading element  700 , such as a customer tray, aligner, or the like, and moves them (in the direction of the arrow) above a carrier board  500  located a reference height H. The aligner, an example of the loading element  700 , will be explained in detail later. 
     2. Release the Holding State of the Carrier Board (Refer to  FIG. 11 ) 
     An opener  900 , located at the lower side of the carrier board  500 , rises (in the direction of arrow {circle around (a)}) and operates the holding units  513   a  and  513   b  of the inserts  510  of the carrier board  500 , thereby releasing the holding state of the holding unit  513   a  and  513   b . When the opener  900  rises, the insert  510 , installed to the carrier board  500 , is lifted by h (refer to arrow {circle around (b)}). 
     As exaggeratedly shown in  FIG. 12 , the carrier board  500  is equipped with a guide rail  800  on its lower surface. The lower surface is located at the reference height H with a vertical movement tolerance h 1  by the guide rail  800 . The guide rail  800  serves to prevent the separation of the carrier board  500  in the upper direction or lower direction. In addition, the insert  510  is also installed to the carrier board  500 , so as to have a vertical movement tolerance h 2  (h 2 =h−h 1 ). In that case, the insert  510  can be ascended by the movement tolerance itself. Therefore, when the opener  900  rises, the insert  510  is ascended by h (h=h 2 +h 1 ) 
     Since technology related to openers is already well-known via various documents, for example, Korean Patent Registration No 10-0687676, etc., a detailed description is not included in this application. 
     3. Set Position Between Picker and Carrier Board (Refer to  FIG. 13 ) 
     The pick-and-place apparatus  200  is lowered toward the carrier board  500  (refer to the arrow direction shown in  FIG. 13 ) so that the position setting pins  213   a - 1  and  213   a - 2  are inserted into the position setting holes  511   a  and  511   b . During this process, the positions between the insert  510  and the picker  212  that picks up a semiconductor device D are precisely set, so as to match the center between the picker  212  and the placement compartment  512  of the insert  510  (Since the picker picks up the center of the semiconductor device, the center of the semiconductor device can be coincident with that of the placement compartment). 
     4. Place and Hold Semiconductor Devices 
     4-1. Place Semiconductor Devices (Refer to  FIG. 14 ) 
     In a state where the positions between the picker  212  and the carrier board  500 , i.e., the picker  212  and the insert  510 , are precisely set as shown in  FIG. 13 , the pick-and-place apparatus  200  continues being lowered (refer to the arrow shown in  FIG. 14 ), so that the semiconductor device D can be precisely placed at the correct position in the placement compartment  512 . Since the lower surface of the stopper STP contacts the upper surface of the insert  510  before the semiconductor device D is placed in the placement compartment  512 , the lowering operation of the pick-and-place apparatus  200  lowers only the picker  212  that is integrally coupled with the body  211 . On the other hand, the guiding member  213   a , which is relatively ascended with respect to the picker  212  but which is stopped actually, compresses a pair of springs  213   b - 1  and  213   b - 2  until the lower surface of the body  211  contacts the upper surface of the stopper STP. 
     4-2. Compress a Pair of Elastic Members (Refer to  FIG. 15 ) 
     In a state where the guiding member  213   a  has relatively risen within a preset range of movement distance with respect to the picker  212  and thus the pair of springs  213   b - 1  and  213   b - 2  are compressed as shown in  FIG. 14 , if the pick-and-place apparatus  200  continues to be lowered as shown in  FIG. 15 , the module-forming block  220  is lowered and a pair of elastic members  214   a  and  214   b , located between the picking apparatus  210  and the module-forming block  220 , are also compressed, so that the picking apparatus  210  is relatively ascended (but stopped actually) with respect to the module-forming block  220 . Therefore, if the picking apparatus  210  has relatively risen within a preset range of movement distance with respect to the module-forming block  220  and thus the pair of elastic members  214   a  and  214   b  have been also compressed, the pick-and-place apparatus  200  stops its lowering operation. 
     The pick-and-place apparatus  200  does not perform an ascending/descending operation until the pick-and-place apparatus  200  loads the semiconductor device D in a state shown in  FIG. 5  and then rises again. After that, the picker  212  is lowered according to an elastic force of the pair of elastic members  214   a  and  214   b.    
     4-3. Continue Placing the Semiconductor Devices (Refer to  FIG. 16 ) 
     When the semiconductor device D is loaded from a correct placement position and the pair of springs  213   b - 1  and  213   b - 2  and the pair of elastic members  214   a  and  214   b  are compressed by preset lengths, respectively, the opener  900  is lowered in the direction of arrow as shown in  FIG. 16  in order to hold the semiconductor device D. In that case, the insert  510  that rose by a height h as the opener  900  was rising lowers by a height h (h=h 1 +h 2 , where h 1  is the lowered height of the carrier board  500  and h 2  is the lowered height of the insert  510 ). While the insert  510  is being lowered, the pair of elastic members  214   a  and  214   b  push the picking apparatus  210  in the lower direction, so that the picking apparatus  210  is lowered by a height h. Therefore, the semiconductor device D sucked and picked up by the picker  212  can continue pushing the placement side of the insert  510 . 
     Since the picker  212  still sucks and picks up the semiconductor device D while the opener  900  is being lowered, the semiconductor device D can stably retain its placement state at the placement position even though a vibration according to the lowering operation of the opener  900  occurs. 
     4-4. Hold Semiconductor Devices (Refer to  FIGS. 17A and 17B ) 
     In a state where the carrier board  500  and the insert  510  have been lowered, if the opener  900  is further lowered in the direction of arrow, as shown in  FIGS. 17A and 17B , the holding units  513   a  and  513   b  hold the semiconductor device D. 
     5. Release a Picking State of the Picker 
     When the holding units  513   a  and  513   b  have performed their holding operations, the vacuum pressure is released so that the picker  212  can release its sucking and picking state of the semiconductor device D. 
     6. Lift of the Pick-and-Place Apparatus (Refer to  FIG. 18 ) 
     When the picker  212  releases the picking state of the semiconductor device D, the pick-and-place apparatus  200  is moved up opposite the carrier board  500 , i.e., in the upper direction (refer to the direction of the arrow). 
     The following description explains the function of the aligner as a loading element of the pick-and-place apparatus  200 . 
     The aligner refers to a loading element that arranges semiconductor devices before the pick-and-place apparatus  200  loads them onto the carrier board  500 . The aligner must be configured to be applied to the pick-and-place apparatus  200  according to an embodiment of the present invention. 
       FIG. 19  is a view illustrating an aligner adapted to the pick-and-place apparatus  200  according to an exemplary embodiment of the present invention. 
     Referring to  FIG. 19 , the aligner  700 A forms a plurality of aligning grooves  710  on which semiconductor devices are loaded and aligned. At both sides of each aligning groove  710 , pin receiving walls  720  are protrudently formed with a relatively high height. The pin receiving walls  720  form pin receiving holes  721  into which the position setting pins  213   a - 1  and  213   a - 2  of the pick-and-place apparatus  200  are inserted. 
     The following description explains a method where the pick-and-place apparatus  200  picks up semiconductor devices from the aligner  700 A, with reference to  FIG. 20 . 
     Referring to  FIG. 20 , when the pick-and-place apparatus  200  is lowered to pick up semiconductor devices loaded on the aligning grooves  710  of the aligner  700 A, the position setting pins  213   a - 1  and  213   a - 2  are inserted into the pin receiving holes  721  and the lower surface of the stopper STP contacts the upper surface of the pin receiving wall  720 . As shown in  FIG. 21 , according as the pick-and-place apparatus  200  continues lowering, the lowering operation of the guiding member  213   a  is stopped but only the picker  212  is still lowered, so that the picker  212  can pick up the semiconductor device D. 
     Although the embodiment of the present invention has been explained based on the pick-and-place apparatus  200  with 16 picking apparatuses  210 , it should be understood that the present invention is not limited to the embodiment. For example, it can be modified in such a way that the pick-and-place apparatus can be equipped with a plurality of modules aligned in parallel, each module having 16 picking apparatuses. 
     As described above, the pick-and-place apparatus according to the present invention can precisely load and place semiconductor devices at a placement position in a loading element (in particular, in a carrier board), thereby guaranteeing the stability of the electrical contact between the semiconductor devices and the tester. 
     While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.