Abstract:
The present invention provides a mounting device for a chip component, allowing short operating time for mounting a chip component after cutting, and capable of reliably mounting only an undamaged, non-defective chip component. The mounting device comprises carriers  10, 16  and  24 , which transport a chip component  6   a , peeled from a holding sheet  4  for holding cut individual chip components  6   a , to a mounting substrate  20 , and mount the chip component  6   a  thereon. The carriers  16  and  24  are provided with measuring terminals  18  and  26  for measuring electric properties of the chip component  6   a  during transporting. A control circuit is provided with the mounting device for controlling the carriers  16  and  24  so as to mount the chip component  6   a  on the mounting substrate  20  only when a measurement of the chip component  6   a  determined through measuring terminals  18  and  26  satisfies mountable conditions.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a mounting device for a chip component, more particularly, a mounting device for a chip component allowing to easily prevent from mounting of a defective chip component found immediately before mounting the same on a substrate. 
         [0003]    2. Description of the Related Art 
         [0004]    When a wafer held on a holding sheet such as adhesive sheet of a wafer table is subject to die cutting and the obtained semiconductor bear chip components are mounted on a mounting substrate, the chip components are conventionally mounted without testing every chip component. Alternatively, the chip components subsequent to cutting on the holding sheet may be subject to individually testing, followed by mounting only the chip components determined as non-defective in the test. 
         [0005]    However, when mounting chip components after peeling from the holding sheet such as adhesive sheet and transporting, the chip components may be damaged by static electricity due to peeling the same from the holding sheet, by colliding force due to ejector pin, etc. In such cases, damaged chip components may also be subject to mounting, and determined as defective in a test after mounting. 
         [0006]    Note that as a mounting device for a mounting chip component such as an IC chip, for example, a device disclosed in Publication of Japanese utility model application H02-120900 is known. In this device, electric properties of chip components kept in a tape carrier are measured and examined before mounting. 
         [0007]    However, in such a mounting device, IC chip determined as non-defective after the measurements may be damaged when taking out from the tape carrier due to static electricity, etc., and there still remains a possibility that the damaged IC chip is mounted. 
         [0008]    Then, chip components peeled from a holding sheet such as an adhesive sheet, or chip components taken out from a tape carrier may be gather in one place prior to mounting for testing, and only those determined as non-defective may be subject to mounting. However, in this method, the tests require fair amount of time, which results in a problem that operating time from wafer cutting step to mounting step takes long. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is made reflecting this situation, and has a purpose to provide a mounting device for a chip component, allowing short operating time for mounting a chip component after cutting and reliable of mounting only an undamaged, non-defective chip component. 
         [0010]    To achieve the above purpose, a mounting device for a chip component according to the present invention comprises 
         [0011]    a carrier for transporting said chip component, removed from a holding part which holds each of cut chip components, to a mounting substrate to mount the same, 
         [0012]    a measuring terminal, provided with at least a part of said carrier, for measuring electric properties of said chip component during transporting, 
         [0013]    a control means for controlling said carrier so as to mount said chip component on said mounting substrate only when a measurement of said chip component determined through said measuring terminal satisfies mountable conditions. 
         [0014]    In the mounting device for a chip component according to the present invention, tests are performed during transportation by the carrier, resulting in short operating time for mounting a chip component after cutting. Also, a chip component, removed from a holding part such as a holding sheet, is tested during transportation, so that it is possible to reliably distinguish a chip component damaged due to peeling. It is also possible to eliminate defective chip components without satisfying mountable conditions during transportation, so that only undamaged, good-quality chip components may be reliably mounted. 
         [0015]    Preferably, said carrier comprises a pick-up head for receiving said chip component removed from said holding part; and a mounting head for mounding said chip component on said mounting substrate. In this case, receiving operation by the pick-up head and mounting operation by the mounting head can be concurrently processed, so that operating time can be further shortened. 
         [0016]    Preferably, said carrier further comprises a carrier table for transporting said chip component, received on said pick-up head, to said mounting head. Said measuring terminal may be provided with at least one of said mounting head and said carrier table. In this case, receiving operation by the pick-up head, mounting operation by the mounting head, and transporting operation by the carrier table can be concurrently processed, and a measurement for testing can be performed during the mounting operation or transporting operation. 
         [0017]    Alternatively, said carrier may further comprise a stationary table for temporarily placing said chip component received on said pick-up head. In this case, said measuring terminal may be provided with at least one of said mounting head and said stationary table. In this case, a measurement for testing can be performed during the mounting operation or during temporarily placing on the stationary table. 
         [0018]    Preferably, said holding part is a holding sheet for holding individual chip components, and may further comprise a peel off means for peeling said chip component from said holding sheet. 
         [0019]    The holding sheet for holding said chip component is attached on a wafer table, and said peel off means may be an ejector pin which is inserted in an opening formed on said wafer table. 
         [0020]    Preferably, a cutting means is placed on said wafer table, and said chip component can be obtained by cutting a wafer placed on said holding sheet and wafer table. In this case, it is possible to shorten operating time from cutting wafer to mounting a chip component. 
         [0021]    Preferably, said carrier contacting with said chip component is grounded. By grounding the carrier, no static electricity is stored between the carrier and the chip component, so that it is possible to prevent damage on the chip component due to static electricity. 
     
    
     
       DESCRIPTION OF THE PREFERRED EMBODIMENTS 
         [0022]    Hereinafter, the present invention will be described based on an embodiment shown in drawings. 
           [0023]      FIG. 1  to  FIG. 16  are diagrams showing processes from wafer cutting to mounting using a mounting device for a chip component according to one embodiment of the present invention. 
           [0024]      FIG. 1  is a cross-sectional view showing a wafer mounting process using a mounting device for a chip component according to one embodiment of the present invention. 
           [0025]      FIG. 2  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 1 . 
           [0026]      FIG. 3  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 2 . 
           [0027]      FIG. 4  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 3 . 
           [0028]      FIG. 5  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 4 . 
           [0029]      FIG. 6  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 5 . 
           [0030]      FIG. 7  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 6 . 
           [0031]      FIG. 8  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 7 . 
           [0032]      FIG. 9  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 8 . 
           [0033]      FIG. 10  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 9 . 
           [0034]      FIG. 11  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 10 . 
           [0035]      FIG. 12  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 11 . 
           [0036]      FIG. 13  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 12 . 
           [0037]      FIG. 14  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 13 . 
           [0038]      FIG. 15  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 14 . 
           [0039]      FIG. 16  is a cross-sectional view showing the continuous step of the wafer mounting process from that of  FIG. 15 . 
       
    
    
       [0040]    As shown in  FIG. 1 , a mounting device according to one embodiment of the present invention comprises a wafer table  2 . On the wafer table  2 , a holding sheet  4  formed by adhesive sheet, etc., is placed. On the holding sheet  4 , a semiconductor wafer  6 , wherein a plurality of predetermined semiconductor element circuits are formed, is detachably held. 
         [0041]    As shown in  FIG. 2 , the mounting device of the present embodiment is provided with a dicer (cutter)  8  as a cutting means on the wafer table  2 . The dicer  8  cut the semiconductor wafer  6  on the holding sheet  4  and wafer table  2  to obtain a plurality of chip components  6   a . As the chip component  6   a , although not particularly limited, in the present embodiment, there may be illustrated an IC chip on which a terminal electrode is formed. 
         [0042]    As shown in  FIG. 3 , the mounting device of the present embodiment comprises a pick-up head  10  for picking up each of the chip components  6   a , cut on the holding sheet  4  and wafer table  2 , from the wafer table  2 . The pick-up head  10  has a suction nozzle structure which allows suction holding of the chip component  6   a.    
         [0043]    The pick-up head  10  is subject to drive control to be movable in a vertical direction and horizontal direction, and can move back and forth between the later-mentioned carrier table  16  and the wafer table  2  in horizontal direction. The drive control of the pick-up head  10  is performed by a control circuit  11 . 
         [0044]    Also, on the wafer table  2 , a thrusting hole  14  is formed to correspond to the back surface of each chip component  6   a , in which an ejector pin  12  is inserted. The ejector pin  12  can be inserted in each thrusting hole  14 . 
         [0045]    To pick up a specific chip component  6   a  shown in  FIG. 3  from the wafer table  2 , first, the ejector pin is inserted from underneath of the thrusting hole  14  corresponding to the back surface (lower surface) of the specific chip component  6   a  to apply on the lower surface of the holding sheet  4  as shown in  FIG. 4 . Simultaneously, the pick-up head  10  is pressed on the specific chip component  6   a  to start suction of the pick-up head. 
         [0046]    Next, as shown in  FIG. 5 , the ejector pin  12  is further pressed up. The pick-up head  10  is simultaneously pushed upward as well as pressing-up motion of the ejector pin. As a result, the chip component  6   a  is peeled from the holding sheet  4  except for a portion between the ejector pin  12  and chip component  6   a.    
         [0047]    Then, as shown in  FIG. 6 , by continuously suction holding the chip component  6   a  by the pick-up head  10  and pressing the ejector pin  12  downward without changing the position of the pick-up head  10 , the holding sheet  4  returns downward, due to restoring force of the holding sheet  4 , to the lower direction so as to firmly attach to the wafer table  2 . As a result, the chip component  6   a  is completely peeled from the holding sheet  4 . 
         [0048]    As shown in  FIG. 7 , the mounting device of the present embodiment comprises a carrier table  16 . The carrier table  16  is provided in a horizontally different position from that of the wafer table  2  shown in  FIG. 1  to  FIG. 6 . The carrier table  16  is movable at least in a horizontal direction and may be movable in a vertical direction as well. A first measuring terminal  18  is rotatably attached to the carrier table  16 . Drive control of the carrier table  16  is performed by a control circuit  11 . 
         [0049]    As shown in  FIG. 7  to  FIG. 9 , the pick-up head  10  suction holds the chip component  6   a  at the lower side, and horizontally moves to the upside of the carrier table  16 . Just above the carrier table  16 , the pick-up head  10  moves down to the upper surface of the carrier table  16 . Then, while contacting the lower surface of the chip component  6   a  with the upper surface of the table  16 , the head  10  releases the suction holding of the chip component  6   a , and as shown in  FIG. 10 , the head  10  moves upward with regard to the chip component  6   a . As a result, the chip component  6   a  is received on the upper side of the table  16 . 
         [0050]    As shown in  FIG. 11 , the pick-up head  10  horizontally moves away from the carrier table  16 , and returns to the original pick-up position shown in  FIG. 3 . During and around the above operation, in the carrier table  16 , the first measuring terminal  18  turns and connects to an external terminal of the chip component  6   a . The first measuring terminal  18  is connected to an inspection circuit attached in or out of the carrier table  16 . The inspection circuit can be built into the control circuit  11 . 
         [0051]    In the inspection circuit, electric properties, such as inter-terminal current, inter-terminal resistance, inter-terminal capacitance, inter-wiring capacity, inter-wiring resistance, via chain resistance and interlayer capacity, of the chip component can be measured through the first measuring terminal  18 . Test of the chip component  6   a  through the first measuring terminal  18  is performed during transporting the chip component  6   a  after it is received on the carrier table  16 . The test may be performed while the carrier table is at rest, but it is preferable to test while it moves. 
         [0052]    As shown in  FIG. 12 , the mounting device of the present embodiment comprises a substrate table  22 , which a mounting substrate  20  is detachably positioned in and fixed to. The substrate table  22  is provided in a horizontally different position from that of the wafer table  2  shown in  FIG. 1  to  FIG. 6 . On the substrate table  22 , a mounting head  24 , which can suction hold the chip component  6   a , is placed to be movable at least in a vertical direction. 
         [0053]    Also, the mounting head  24  can relatively move in a horizontal direction with respect to the substrate table  22 . Note that the substrate table  22  may be constructed to be movable in a horizontal direction with respect to the mounting head  24 . Drive control of the mounting head  24  and substrate table  22  can be performed by the control circuit  11 . 
         [0054]    A second measuring terminal  26  is attached to the mounting head  24 . The second measuring terminal  26  is, as described below, connected to the external terminal of the chip component  6   a . The second measuring terminal  26  is connected to an inspection circuit attached into or out of the mounting head  24 . The inspection circuit may be built in the control circuit  11 . 
         [0055]    The inspection circuit may be same as or different from the inspection circuit to which the first measuring terminal is connected. Inspection items tested through the second measuring terminal  26  are preferably different from those tested through the first measuring terminal  18 . This is because various tests can be done effectively on the same chip component  6   a.    
         [0056]    As shown in  FIG. 12  to  FIG. 13 , while the mounting head  24  is superjacent to the substrate table  22 , the carrier table moves in a horizontal direction, and is positioned just below the mounting head  24 . On the carrier table  16 , the chip component  6   a  is held. While the carrier table  16  is positioned just below the mounting head  24 , the first measuring terminal turns, and is disconnected with the chip component  6   a.    
         [0057]    In this situation, as shown in  FIG. 14 , the mounting head  24  moves downward, contacts with the upper surface of the chip component  6   a  held on the upper surface of the carrier table  16 , so that the mounting head  24  starts the suction. During and around the above operation, or simultaneously, the carrier table  16  releases the suction holding of the chip component  6   a.    
         [0058]    Subsequently, as shown in  FIG. 15 , the mounting head  24  moves upward while keeping the suction holding of the chip component  6   a  at the lower side, so that the chip component  6   a  is transferred from the carrier table  16  to the mounting head  24 . When the mounting head  24  receives the chip component  6   a , the second measuring terminal  26  is automatically connected to the external terminal of the chip component  6   a . Then, the carrier table  16  horizontally moves into the position to receive the chip component  6   a  from the pick-up head  10  shown in  FIG. 7  to  FIG. 9 . 
         [0059]    When the carrier table  16  horizontally moves to a position not at all to cause an obstruction for vertical movement of the mounting head  24 , the mounting head  24  moves downward in a vertical direction (Z-axis direction) as shown in  FIG. 16 , so that the lower surface of the chip component  6   a , which is suction held at the lower side of the mounting head  24 , is applied onto a predetermined position in a horizontal direction (X-Y direction) of the mounting substrate  20  to mount. 
         [0060]    While moving the mounting head  24  upward in the Z-axis direction as shown in  FIG. 14  to  FIG. 15 , or while moving the mounting head  24  downward in the Z-axis direction as shown in  FIG. 15  to  FIG. 16 , the chip component  6   a  is tested through the second measuring terminal  24  as with the first measuring terminal  18 . 
         [0061]    As shown in  FIG. 16 , the test of the chip component  6   a  may be performed after applying the lower surface of the chip component  6   a  onto the surface of the mounting substrate  20 . In this case, it is possible to perform tests such as measurements for checking the connection between the chip component  6   a  and the mounting substrate  20 . 
         [0062]    When a defect in the chip component  6   a  is detected after applying the lower surface of the chip component  6   a  onto a predetermined position in the horizontal direction (X-Y direction) of the mounting substrate  20  (e.g. in case of not satisfying the mountable conditions), the chip component  6   a  once contacted with the substrate  20  can be retreated or discarded. Specifically, the chip component  6   a  is suction held by the mounting head  24 , received on the carrier table  16  and transported to a retreating position or a discarding position by the carrier table. 
         [0063]    When a defect in the chip component  6   a  is detected through the second measuring terminal  26  before applying the lower surface of the chip component  6   a  onto the surface of the mounting substrate  20 , the chip component  6   a  detected as defective can also be retreated or discard as above. 
         [0064]    In the mounting device for a chip component according to the present embodiment, the chip component  6   a  is tested during transportation, resulting in shortening the operating time between cutting the chip component  6   a  on the wafer table  2  shown in  FIG. 2  and mounting the same on the mounting substrate  20  shown in  FIG. 16 . In addition, by testing the chip component  6   a  after peeling from the holding sheet  4  shown in  FIG. 4  to  FIG. 6  during transportation, it is possible to reliably detect the chip component  6   a  damaged due to peeling from the holding sheet  4 . Also, any defective chip component  6   a  not satisfying the mountable conditions can be eliminated during transportation, so that it is possible to reliably mount only undamaged, non-defective chip components  6   a  one after another on the mounting substrate  20  shown in  FIG. 16 . 
         [0065]    Also, the mounting device in the present embodiment comprises the pick-up head  10  for receiving the chip component  6   a  peeled from the holding sheet  4 , and the mounting head  24  for mounting the chip component  6   a  on the mounting substrate  20 . Therefore, the receiving operation by the pick-up head  10  and the mounting operation by the mounting head  24  can be concurrently performed, resulting in further shortening of the operating time. 
         [0066]    Also, the mounting device of the present embodiment further comprises the carrier table  16  for transporting the chip component  6   a  received on the pick-up head  10 . Therefore, the receiving operation by the pick-up head  10 , the mounting operation by the mounting head  24 , and the transporting operation by the carrier table  16  can be concurrently performed, so that it is possible to make measurements for testing during the mounting operation or transporting operation of the chip component  6   a.    
         [0067]    Note that the present invention is not limited to the above-described embodiment, and can be variously modified in the scope of the present invention. 
         [0068]    For example, it may be possible to use a stationary table instead of the carrier table  16  shown in  FIG. 7  to  FIG. 16 , and to provide the first measuring terminal  18  in the stationary table, making the mounting head  24  movable horizontally to the receiving position of the chip component  6   a  from the pick-up head  10  shown in  FIG. 8  to  FIG. 11 . In this case, measurements for testing can be made during temporarily placing of the chip component  6   a  on the stationary table. 
         [0069]    Also, as a peel off means for the chip component  6   a  from the holding sheet  4  shown in  FIG. 3  to  FIG. 6 , there may be mentioned a thrusting rod and an ultraviolet irradiator instead of the ejector pin  12 . In the ultraviolet irradiator, ultraviolet is irradiated to the holding sheet  4  to reduce adhesion of the holding sheet  4 , making it easier to peel the chip component  6   a  from the holding sheet  4 . 
         [0070]    Further, in the above-identified embodiment, it is preferred to ground the pick-up head  10 , the carrier table and the mounting head  24 . By grounding these, no static electricity is stored between the chip component  6   a  and these, so that it is possible to prevent damages due to static electricity on the chip component  6   a.