Abstract:
A semiconductor device socket having one or more heat sinks for dissipating heat from the object under test. The one or more heat sinks are held by arm members disposed in the semiconductor device socket for providing rotational movement about the object under test accommodation portion.

Description:
This application is based on Patent Application No. 2001-241318 filed Aug. 8, 2001 in Japan, the content of which is incorporated hereinto by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a semiconductor device-socket used for testing the semiconductor device. 
     2. Description of the Related Art 
     Semiconductor devices to be mounted to an electronic equipment or others are subjected to various tests prior to being mounted so that latent defects thereof are removed. Such tests are carried out in a non-destructive manner by the application of voltage stress in correspondence to thermal and mechanical environmental tests, the high-temperature operation or the high-temperature stock. Of the above-mentioned various tests, it has been said that a burn-in test is effective for removing integrated circuits having infant mortality failures, in which a performance test is carried out under a high-temperature condition for a predetermined period. 
     A semiconductor device-socket used for such a test is disclosed, for example, in Japanese Patent Application Laying-open No. 2001-013207, wherein the socket is disposed on a printed circuit board having an input/output section for supplying a predetermined test voltage to the semiconductor device to be tested and issuing an abnormality detection signal generated therefrom, representing a short-circuit accident or others. The semiconductor device-socket is fixed on the printed circuit board and includes a socket body secured on the printed circuit board, the socket body having an accommodation portion for positioning and holding a semiconductor element, for example, of a BGA (ball grid array) type as the semiconductor device. 
     In the above structure, the burn-in test is carried out on the semiconductor device by supplying a predetermined testing signal to the printed circuit board. 
     During this test, a semiconductor device has been initiated in which heat generated in the semiconductor element due to the test signal is moved away from the semiconductor element to the printed circuit board and the socket body or into the atmosphere, for example, through ventilation holes. Or, there is a proposal in Japanese Patent Application Laying-open No. 11-097818 (1999) in that, for dissipating heat generated from the semiconductor element to the printed circuit board, a heat-conductive part effective for conducting such heat to the printed circuit board is provided on the printed circuit board. 
     However, in a case of a semiconductor element used for a central processing unit (CPU) generating a relatively large heat value, for example, there might be a risk in that the heat generated during the test is not sufficiently dissipated through the printed circuit board to not provide cooling for the semiconductor element itself. 
     SUMMARY OF THE INVENTION 
     In view of the above problems, an object of the present invention is to provide a semiconductor device-socket used for testing a semiconductor device capable of effectively dissipating heat generated in the semiconductor device to provide cooling for the semiconductor device during the test. 
     To achieve the above object, a semiconductor device-socket is provided, comprising a socket body having an accommodation portion for accommodating a semiconductor device and electrically connected to an input/output substrate for inputting/outputting a test signal relative to terminals of the semiconductor device accommodated in the accommodation portion; a radiating member held by arm members providing rotational movement in the circumference of the accommodation portion, for removing heat from the semiconductor device; and an arm member rotational movement mechanism provided in the socket body, for moving rotationally the arm members in one direction so that the radiating member is brought into contact with the surface of the semiconductor device accommodated in the accommodation portion and rotating the arm members in the other direction so that the radiating member is separated from the surface of the semiconductor device. 
     As apparent from the above description, since the radiating member for dissipating heat from the semiconductor device is held by the arm members providing rotational movement about the accommodation portion, it is possible to effectively remove heat generated in the semiconductor device to provide cooling for the semiconductor device during the test. 
     The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a first embodiment of a semiconductor device-socket according to the present invention, illustrating an appearance thereof; 
     FIG. 2 is a perspective view made available for the operation of the embodiment shown in FIG. 1; 
     FIG. 3 is an exploded perspective view of a structure for retaining a heat sink used in the embodiment shown in FIG. 1; 
     FIG. 4 is a perspective view of the structure for retaining a heat sink used in the embodiment shown in FIG. 1; 
     FIG. 5 is a view made available for illustrating the operation of the heat sink of the embodiment shown in FIG. 1; 
     FIG. 6 is a view made available for illustrating the operation of a comparative example; 
     FIG. 7 is a perspective view of a second embodiment of a semiconductor device-socket according to the present invention, illustrating an appearance thereof; 
     FIG. 8 is a perspective view made available for illustrating the operation of the embodiment shown in FIG. 7; 
     FIG. 9 is a perspective view of the structure for retaining a heat sink used in the embodiment shown in FIG. 7; 
     FIG. 10 is a partial perspective view of the structure for retaining a heat sink used in the embodiment shown in FIG. 7; and 
     FIG. 11 is a view made available for illustrating the operation of the heat sink of the embodiment shown in FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 is a perspective view of a first embodiment of a semiconductor device-socket according to the present invention, illustrating an appearance thereof; 
     In FIG. 1, a plurality of semiconductor device-sockets are arranged at predetermined positions, for example, on a printed circuit board  22  in every directions. The semiconductor device-socket includes a socket body  2  having an accommodation portion for holding a semiconductor element to be tested (hereinafter referred to as an object under test), a frame member  4  movable upward and downward relative to the socket body  2 , heat sinks  34  and  36  as a heat-sink member for exoergic cooling the tested object, disposed in the accommodation portion, and pressing members  38 ,  40  (see FIG. 2) for pressing a terminal section of the object under test disposed in the accommodation portion onto contact pins electrically connected to the electrodes of the printed circuit board  22 . 
     In the printed circuit board  22 , a group of electrodes is provided in correspondence to the respective socket body  2 . The respective electrode group is electrically connected to a signal input/output section of the printed circuit board  22  for inputting and outputting the test signal through an electro-conductive layer not shown. 
     The socket body  2  molded in a resin has an object under test accommodation portion  24  for accommodating the tested object approximately in a central area thereof as shown in FIG.  2 . The tested object accommodation portion  24  has, for example, a generally square recess. At four corners of walls defining the recess, positioning members  26 A,  26 B,  26 C and  26 D are provided for locating connecting terminal of the object under test  30  relatively to contact pins. Each of the positioning members  26 A,  26 B,  26 C and  26 D has a notch engageable with each of the four corners of a wiring substrate section of the object under test  30 . 
     The object under test  30  is, for example, a so-called semi-finished product prior to being packaged, which includes a semiconductor element having internal electronic circuits and a circuit board section electrically connected to the semiconductor element. The wiring substrate section has the above-mentioned group of connection terminals on a surface opposed to the group of contact pins. 
     Also, as shown in FIG. 1, support sections  2 B and  2 D are provided in which one end of an arm member  14 ,  18  described later is supported in a rotational movably manner at two places around each of a pair of opposite edges in the other side of the object under test accommodation portion  24 . 
     The one end of the arm member  14 ,  18  is coupled to the inner side of a front end portion of a pressing member supports  16 ,  20  by means of a connecting pin  28 . 
     A pressing body  38 ,  40  is provided at a position of the pressing member support  16 ,  20  closer to the front end thereof than the front end portion to which the one end of the arm member  14 ,  18  is coupled. As shown in FIG. 1, when the frame member  4  occupies the uppermost position, a force of an resilient member for biasing the above-mentioned frame member  4  upward operates to the pressing member support  16 ,  20  via a predetermined transmitting member, so that the pressing member  38 ,  40  thereof touches to the wiring substrate portion of the object under test  30  at a predetermined pressure. 
     The frame member  4  encircling the upper area of the object under test accommodation portion  24  has an opening  4   a  at a center thereof, through which the object under test accommodation portion  24  or the object under test  30  is selectively passes, and as shown in FIGS. 1 and 2, is supported to be movable upward and downward relative to the socket body  2 . FIG. 1 illustrate a state wherein the frame member  4  occupies the uppermost position, while FIG. 2 illustrates a state wherein the frame member  4  for covering the socket body  2  occupies the lowermost position. 
     Although not illustrated, a plurality of resilient members for biasing the frame member  4  upward are provided between the inner side of the frame member  4  and the socket body  2 . 
     Further, grooves  4   s  to be engageable with heat sink holding members  8  and  12  described later and grooves  4   g  to be engageable with the pressing member supports  16  and  20  described later are formed on the periphery of the opening  4   a  of the frame member  4 . 
     In the vicinity of the grooves  4   s  of the frame member  4 , supporting portions for rotational movably supporting one end of the heat sink holding member  8  and  12  are provided. Also, in the vicinity of the grooves  4   g  of the frame member  4 , supporting portions for rotational movably supporting one end of the pressing member supports  16  and  20  are provided. Each of these supporting portions has a support pin fitted in a hole of the one end of the heat sink holding member  8 ,  12  and a hole of the one end of the pressing member support  16 ,  20 . 
     Support sections  2 A and  2 C are provided in which one end of an arm member  6 ,  10  described later is supported in a rotatable manner at two positions around each of the other pair of opposite edges in the object under test accommodation portion  24 . 
     One ends of the arm members  6  and  10  are coupled to the inside of a front end portion of the heat sink holding members  8  and  12 , respectively, with connecting pins  42 . 
     Since the structures for holding the heat sinks  36  and  34  by the heat sink holding members  8  and  12  are identical to each other, the holding structure for the heat sink  36  by the heat sink holding member  8  will be solely described as shown in FIG. 4 while eliminating the description of the heat sink holding member  12 . 
     Each of the plank-type heat sink members  8  has at one end thereof a hole  8   a  to be fitted in an end portion of the support pin and at the other end thereof has a hole  8   b  to be fitted in an end portion of a support shaft  44  for supporting the heat sink  36 . As shown in FIG. 1, between the respective pair of heat sink holding members  8 , a pressing body  46  is nipped for pressing the wiring substrate of the object under test  30  when the heat sink holding members  8  approach the wiring substrate of the object under test  30 . The opposite ends of the pressing body  46  are fastened to the heat sink holding members  8  by means of screws, respectively. 
     As shown in FIG. 3, the heat sink  36  has a plurality of radiating fins  36   f  arranged at predetermined distance. The heat sink  36  also has an elongate hole  36   a  passing through the radiating fins  36   f  in the arrangement direction. The support shaft  44  is inserted into the elongate hole  36   a . The opposite ends of the support shaft  44  are fixed to the holes  8   b  of the respective heat sink holding members  8 . A plurality of coil springs  45  are provided between the outer periphery of the support shaft  44  and a bottom wall forming part of a slit defined between the radiating fins  36   f  of the heat sink  36 , for biasing the heat sink  36  toward the side of the object under test  30 . Accordingly, the heat sink  36  is rotational movably about the support shaft  44  biased by the elastic force of the coil spring  45 . By varying the elastic force applied by the coil spring  45 , the adhesion of a contact portion  36   t  of the heat sink  36  with the object under test  30  is adjustable. 
     On one side of the heat sink  36 , positioning pins  48 A and  48 B are provided. The positioning pin  48 A is disposed above the elongate hole  36   a  of the heat sink  36 . On the other hand, the positioning pin  48 B is disposed, as shown in FIG. 4, obliquely beneath the positioning pin  48 A across the heat sink holding member  8  between the both at a predetermined gap. A positioning pin  48 C is disposed opposite to the positioning pin  48 B across the heat sink holding member  8  between the both at a predetermined gap. 
     Hereby, the rotation of the heat sink  36  relative to the respective heat sink holding members  8  is restricted by the positioning pins  48 A,  48 B and  48 C. 
     Suppose that there are no positioning pins  48 A and  48 B in the heat sink  36  as shown in FIG. 6, for example. When the heat sink  36  is abruptly separated from the object under test  30 , the heat sink  36  is made to rotate about the support shaft  44  as shown by a solid line. Then, if the touching portion  36   t  of the heat sink  36  is again brought into contact with the object under test  30  as shown by a chain double-dashed line, the heat sink  36  may approach the respective heat sink holding members  8  as shown by a chain double-dashed line in a rotating state. As a result, there is a risk in that a corner of the end of the heat sink  36  may injure the surface of the object under test  30 . 
     Contrarily, according to the first embodiment of the present invention, since the rotation of the heat sink  36  relative to the respective heat sink holding members  8  is restricted within a predetermined angular range by the contact of the outer circumference of the positioning pins  48 A,  48 B and  48 C with the heat sink holding member  8 , a risk is avoidable in that the surface of the object under test  30  is injured by the corner of the end of the heat sink  36 . 
     In the above structure, upon mounting the object under test  30  onto the socket body  2 , for example, by holding the object under test  30  by a robot hand not shown and accommodating the same in the object under test accommodation portion  24  through the opening  4   a  of the frame member  4 , the frame member  4  is first lowered to a position shown in FIG. 2 against a bias of the resilient member by the robot hand not shown. In that case, since one end of the heat sink holding members  8  and  12  is moved downward together with the frame member  4 , the arm members  6  and  10  are made to move rotationaly. Thus, as shown in FIG. 2, the heat sinks  34  and  36  are separated from the object under test accommodation portion  24  and in a inverted state. 
     Since one end of the pressing member supports  16  and  20  is also moved down together with the frame member  4 , the arm members  14  and  16  are made to move rotationaly. Accordingly, as shown in FIG. 2, the presser bodies  38  and  40  are separated from the object under test accommodation portion  24  and in a inverted state. 
     Next, the object under test  30  is positioned by resting on the positioning members  26 A,  26 B,  26 C and  26 D in the bottom of the object under test accommodation portion  24 , whereby the connection terminal section of the object under test  30  is located relative to a group of contact pins (not illustrated). 
     When the frame member  4  is moved upward by the robot hand not shown and suspended at a position shown in FIG. 1, the wiring substrate of the object under test  30  is pressed toward the contact pins by the pressing bodies  38 ,  40  and  46 . Also, as shown in FIG. 5, the touching portions  34   t  and  36   t  of the heat sinks  34  and  36  are solely brought into contact with the outer surface of the semiconductor element which is the object under test  30 . In that case, as described above, since the relative rotation of the heat sinks  34  and  36  is restricted within a predetermined range, there is no risk in that the object under test  30  is injured by the corners of the heat sinks  34  and  36  when the both approach each other. 
     Thereafter, a predetermined test signal is issued in a predetermined atmosphere to the object under test  30  through the printed circuit board  22  and the group of contact pins, and the test is carried out on the object under test  30 , during which heat generated in the object under test  30  is effectively dissipated through the heat sinks  34  and  36 . 
     Further, when the object under test  30  is removed from the semiconductor socket after the completion of the test, the frame member  4  is again lowered by the robot hand not shown as described above, after which the object under test  30  finishing the test is removed from the object under test accommodation portion  24 . 
     FIGS. 7 and 8 illustrate a second embodiment of a semiconductor socket according to the present invention, in which a object under test is mounted. 
     In this regard, in the embodiment shown in FIGS. 7 and 8, the same reference numerals are used for denoting the same or similar elements of the embodiment shown in FIGS. 1 and 2, and the explanation thereof will be eliminated for avoiding the duplication. 
     One ends of the arm members  64  and  66  supported in a rotational movably manner on the socket body  2  are coupled to the inside of front end portions of the heat sink holding members  58  and  62 , respectively, by the connecting pins  66 . 
     Since structures for holding the heat sinks  52  and  50  are identical to each other as shown in FIGS. 9 and 10, the explanation will be made solely on the structure for the heat sink  52  by the heat sink holding member  58  and that of the heat sink holding member  62  will be eliminated. 
     Each of the plank-type heat sink holding members  58  is provided at one end thereof with a hole  58   a  to be fitted into an end of the support pin, and at the other end thereof with an elongate hole  58   b  to be fitted into an end of the support shaft  68  for supporting the heat sink  52 . As shown in FIG. 8, a pressing body  56  for pressing the wiring substrate of the object under test  30  while each of heat sink holding members  58  gets near the wiring substrate of the object under test  30  is nipped between the respective heat sink holding members  58 . The opposite end portions of the pressing body  56  are fastened to the heat sink holding member  58 , respectively. On the other hand, the pressing body  56  is also nipped between the respective heat sink holding members  62 . 
     The heat sink  52  has a plurality of radiating fins  52   f  arranged at a predetermined distance as shown in FIGS. 9 and 10. The heat sink  52  has a hole  52   a  passing through the radiating fins  52   f  in the arrangement direction thereof. The support shaft  68  is inserted into the hole  52   a . The opposite ends of the support shaft  68  are engaged with the elongate hole  58   b  of the respective heat sink holding members  58 . 
     A coupling  52   s  is provided in each of two portions of the heat sink  52 , into which one end of the respective heat sink holding member  58  is inserted and coupled. The coupling  52   s  is provided in correspondence to the distance between the respective heat sink holding members  58 . 
     A positioning regulation plate  70  and an end of the heat sink holding member  58  are inserted in an overlapped state into the coupling  52   s . Between the outer circumference of the support shaft  68  and the bottom of the coupling  52   s , a coil spring  59  is disposed for biasing the touching portion of the heat sink  52  to the object under test. Accordingly, the heat sink  52  is rotational movably about the support shaft  68  biased by the elastic force of the coil spring  59 . Also, by varying the bias of the coil spring  59 , the adhesion of an touching portion of the heat sink  52  with the object under test is adjustable. 
     The positioning regulation plate  70  has a through-hole  70   a  at a position corresponding to the elongate hole  58   a  in the respective heat sink holding member  58  and the hole  52   a  of the heat sink  52 . Also, below the through-hole  70   a , a notch  70   b  is formed. The positioning regulation plate  70  has a step  70 R at a longer side end thereof, engageable with an end of the heat sink holding member  58 . 
     Hereby, the relative rotation of the heat sink  52  relative to the respective heat sink holding member  58  is restricted by the engagement of the step  70 R of the positioning plate  70  with the end of the heat sink holding member  58 . 
     Even in such a structure, in the same manner as in the above embodiment, after the frame member  4  has been lowered, the object under test  30  is placed and positioned on the positioning portions  26 A,  26 B,  26 C and  26 D in the object under test accommodation portion  24 , whereby the connection terminal section of the object under test  30  is positioned to the group of contact pins (not shown). 
     Then, the frame member  4  is lifted by the robot hand not shown and suspended at a position shown in FIG. 7, at which the wiring substrate of the object under test  30  is pressed onto the contact pins by the presser bodies  38 ,  40  and  56 . Also, as shown in FIG. 11, the touching portions  50   t  and  52   t  of the heat sinks  50  and  52  are solely brought into contact with the surface of the semiconductor element which is the object under test  30 . In that case, as described above, since the relative rotation of the heat sinks  50  and  52  is restricted within a predetermined range, there is no risk in that the object under test  30  is injured by the corner of the heat sink  50  or  52 . 
     Thereafter, a predetermined signal is issued to the object under test  30  through the printed circuit board  22  into the predetermined atmosphere and the group of contact pins, and the test is carried out on the object under test  30 . 
     The present invention has been described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and it is the intention, therefore, in the appended claims to cover all such changes and modifications as fall within the true spirit of the invention.