Abstract:
Disclosed is a probe assembly for use in electrical testing of an object, a probe, and a method of making the probe assembly. The probe assembly has a probe supporter body elongated in a first direction and comprising a first side surface, a second side surface, a first facing surface and a second facing surface, wherein the first and second facing surfaces are configured to face a testing object, wherein the first and second facing surfaces are substantially nonparallel to each other. The assembly further has a plurality of first slots formed on the first side surface and the first facing surface and a plurality of second slots formed on the second side surface and the second facing surface. Each slot is configured to receive a portion of a probe.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
       [0001]    This application claims priority to and the benefit of Korean Patent Application Nos. 10-2007-0059161 and 10-2007-0059164, both filed Jun. 15, 2007, the disclosures of which are incorporated herein by reference in its entirety. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    The present disclosure relates to a probe card and, more particularly, to a probe assembly for use in testing electrical characteristics of a testing object such as a semiconductor wafer, a flat panel display. 
         [0004]    2. Description of the Related Technology 
         [0005]    Semiconductor devices are manufactured through a variety of processes including wafer production, wafer test, die packaging and so forth. The wafer test refers to a so-called electrical die sorting test for testing electrical characteristics of the semiconductor devices. In the electrical die sorting test, the semiconductor devices are sorted into acceptable products and unacceptable products by bringing probe pins of a probe card into contact with electrode pads of the semiconductor devices and then allowing an electric current to flow through the electrode pads of the semiconductor devices. In addition to testing the semiconductor devices, the probe card is used in testing data/gate lines in a cell process of flat displays such as a TFT-LCD (Thin Film Transistor-Liquid Crystal Display), a PDP (Plasma Display Panel), an OEL (Organic Electro-Luminescence) and the like. 
         [0006]    U.S. Pat. Nos. 7,150,095 and 7,138,812 disclose probe cards in which needle type probes are connected to a printed circuit board. Each of the probe cards disclosed in these patent documents includes a supporter for supporting probes on a printed circuit board. The probes are fixed to the supporter by means of an insulating material and electrically connected to the printed circuit board by soldering. 
         [0007]    With the probe cards disclosed in the above patent documents, however, the probes need to be aligned with the supporter through the use of a probe-positioning jig in order for a worker to fix the probes to the supporter, and the soldering has to be performed to bond the probes to the printed circuit board. This sharply reduces the productivity of the probe cards and makes it quite difficult to evenly align the probes to the supporter. 
         [0008]    Furthermore, the probe cards make it difficult to repair or replace the probes on a one-by-one basis because the probes are soldered to the printed circuit board. In other words, when one of the probes is defective, it is impossible to remove only the defective probe. There is no choice but to replace the probe card having the defective probe as a whole. 
         [0009]    Moreover, in the probe cards, the probes are coated with an insulating material in order to prevent short-circuit of the probes, which leads to increased production cost and reduced productivity. 
         [0010]    In recent years, the diameter of a wafer tends to be increased to 200 mm or more in an effort to improve the yield rate of semiconductor chips. Furthermore, the pattern of a wafer grows finer and finer. For these reasons, it is necessary to perform touchdown of a probe card several times while a single sheet of wafer is inspected with the probe card. Increase in the frequency of touchdown of a probe card leads to prolonged inspection time and rapid wear and damage of probes, thereby shortening the lifespan of the probe card. 
         [0011]    The foregoing discussion is to provide general background information, and does not constitute an admission of prior art. 
       SUMMARY 
       [0012]    One aspect of the invention provide a probe assembly for use in electrical testing of an object, which comprises: a probe supporter body elongated in a first direction and comprising a first side surface, a second side surface, a first facing surface and a second facing surface, wherein the first and second facing surfaces are configured to face a testing object, wherein the first and second facing surfaces are substantially nonparallel to each other; a plurality of first slots formed on the first side surface and the first facing surface, wherein each first slot is configured to receive a portion of a probe; a plurality of second slots formed on the second side surface and the second facing surface, wherein each second slot is configured to receive a portion of a probe. 
         [0013]    In the foregoing assembly, the probe supporter body may have a cross-section having a generally gable shape. The first facing surface and the first side surface form a first angle therebetween, wherein the second facing surface and the second side surface form a second angle therebetween, and wherein the first and second angle may be about the same. Each first slot may comprise a portion extending in a second direction that is substantially perpendicular to the first direction, wherein each second slot may comprise a portion extending in the second direction. Each first slot may comprise a portion extending in a third direction that is substantially perpendicular to the first direction and substantially slanted relative to the second direction, wherein each second slot may comprise a portion extending in a fourth second direction that is substantially perpendicular to the first direction and substantially slanted relative to the second direction, wherein the third direction is not parallel to the fourth direction. 
         [0014]    Still in the foregoing assembly, the probe assembly may comprise one of the plurality of first slots which does not overlap any one of the plurality of second slots when viewed in a direction perpendicular to the first side surface. The probe assembly may comprise one of the plurality of first slots, which has a width that partially overlaps with a width of one of the plurality of second slots when viewed in a direction perpendicular to the first side surface. The probe assembly may comprise one of the plurality of first slots that substantially eclipses one of the plurality of second slots when viewed in a direction perpendicular to the first side surface. The first and second side surfaces may be substantially parallel to each other. The first facing surface may be substantially slanted with respect to the first side surface. 
         [0015]    Further in the foregoing assembly, the probe assembly may further comprise a first probe engaged with one of the plurality of first slots, and a second probe engaged with one of the plurality of second slots. The first probe may comprise a first arm generally extending in a second direction perpendicular to the first direction, wherein a portion of the first arm is inserted in the one of the plurality of first slots, a second arm electrically and physically connected to the first arm and generally extending in a third direction substantially perpendicular to the first direction and substantially slanted with respect to the second direction, wherein a portion of the second arm is inserted in the one of the plurality of first slots, a first terminal portion formed at a distal end of the first arm and comprising a first tip configured to contact a first electrode, and a second terminal portion formed at a distal end of the second arm and comprising a second tip configured to contact a second electrode. 
         [0016]    Still further in the foregoing assembly, the probe assembly may further comprise a probe engaged with one of the plurality of first slots, and may further comprise a channel generally extending in the first direction and disposed between the first facing surface and the second facing surface, wherein the probe may comprise a projection projecting into the channel and further configured to limit the probe&#39;s movement in a direction perpendicular to the first side surface. The probe assembly may further comprise an additional facing surface which is substantially parallel to the first facing surface, wherein the channel is located between the first facing surface and the additional facing surface, and an additional slot formed on the additional facing surface configured to receive a portion of the probe. 
         [0017]    Another aspect of the invention provides a probe for use in a probe assembly for electrical testing, which comprises: a first arm extending generally in a fifth direction; a second arm electrically and physically connected to the first arm and extending generally in a sixth direction substantially slanted with respect to the fifth direction; a first terminal portion formed at a distal end of the first arm and comprising a first tip configured to form an electrical and physical contact with a first device, wherein the first terminal portion is configured to allow the first tip to elastically move generally in the fifth direction; and a second terminal portion formed at a distal end of the second arm and comprising a second tip configured to form an electrical and physical contact with a second device, wherein the second terminal portion is configured to allow the second tip to elastically move generally in the fifth direction. 
         [0018]    In the foregoing probe, the second arm may have an upper surface and the probe may further comprise a projection extending from the upper surface. The second terminal portion may comprise a resilient extension between the second arm and the second tip, wherein the resilient extension may generally extend in the fifth direction. 
         [0019]    Still another aspect of the invention provides a method of making a probe assembly for use in electrical testing of an object, the method comprising: providing a probe supporter which comprises: a probe supporter body elongated in a first direction and comprising a first side surface, a second side surface, a first facing surface and a second facing surface which generally extend in the first direction, wherein the first and second facing surfaces are substantially nonparallel to each other, a plurality of first slots formed on the first side surface and the first facing surface, and a plurality of second slots formed into the second side surface and the second facing surface; providing a first probe and a second probe; and engaging the first probe with one of the plurality of first slots and the second probe with one of the plurality of second slots. 
         [0020]    In the foregoing method, providing the probe supporter may comprise forming the plurality of first slots using a rotating wheel cutter. In forming the plurality of first slots, the rotating wheel cutter does not contact the second facing surface. 
         [0021]    An aspect of the present invention provides a probe and a probe assembly which are easy to fabricate and can be manufactured with reduced production cost and greatly increased productivity, and a probe card having the same. 
         [0022]    Another aspect of the present invention is to provide a probe and a probe assembly that can save maintenance and repair cost by making it possible to readily remove probes and a supporter from a printed circuit board, and a probe card having the same. 
         [0023]    A further aspect of the present invention is to provide a probe and a probe assembly that can easily inspect an inspection object having a fine pattern by reducing an arrangement interval of probes mounted on a supporter, and a probe card having the same. 
         [0024]    A still further aspect of the present invention is to provide a probe and a probe assembly which are less deformable and enjoy a prolonged lifespan, and a probe card having the same. 
         [0025]    In one aspect of the present invention, there is provided a probe card for use in testing electric characteristics of an inspection object having a plurality of electrode pads, comprising: a printed circuit board through which electric signals are transmitted to the electrode pads of the inspection object; a supporter attached to the printed circuit board, the supporter including a first side surface, a first slanting surface extending obliquely toward a center plane of the supporter from the first side surface and a plurality of first insertion slots formed across the first side surface and the first slanting surface; and a plurality of probes inserted into the first insertion slots, each of the probes including a first arm portion fitted to the first side surface, a second arm portion extending obliquely from the first arm portion so that the second arm portion can be fitted to the first slanting surface, a connection terminal portion joined to a tip end of the first arm portion so that the connection terminal portion can be connected to the printed circuit board and a contact terminal portion joined to a tip end of the second arm portion so that the contact terminal portion can be connected to each of the electrode pads of the inspection object. 
         [0026]    w In another aspect of the present invention, there is provided a probe assembly for transmitting electric signals between an inspection object and a printed circuit board, comprising: a supporter including a first side surface, a first slanting surface extending obliquely toward a center plane of the supporter from the first side surface and a plurality of first insertion slots formed across the first side surface and the first slanting surface; and a plurality of probes inserted into the first insertion slots, each of the probes including a first arm portion fitted to the first side surface, a second arm portion extending obliquely from the first arm portion so that the second arm portion can be fitted to the first slanting surface, a connection terminal portion joined to a tip end of the first arm portion so that the connection terminal portion can be connected to the printed circuit board and a contact terminal portion joined to a tip end of the second arm portion so that the contact terminal portion can be connected to the inspection object. 
         [0027]    In a further aspect of the present invention, there is provided a probe for transmitting electric signals between an inspection object and a printed circuit board, comprising: a first arm portion; a second arm portion extending obliquely from the first arm portion; a connection terminal portion joined to a tip end of the first arm portion so that the connection terminal portion can be connected to the printed circuit board; and a contact terminal portion joined to a tip end of the second arm portion so that the contact terminal portion can be connected to the inspection object. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    The above and other aspects and features of the present invention will become apparent from the following description of embodiments, given in conjunction with the accompanying drawings, in which: 
           [0029]      FIG. 1  is an exploded perspective view schematically showing a probe card in accordance with one embodiment of the present invention; 
           [0030]      FIG. 2  is a perspective view illustrating a plurality of probe assemblies employed in the probe card in accordance with one embodiment of the present invention; 
           [0031]      FIG. 3  is an exploded perspective view showing one of the probe assemblies shown in  FIG. 2 ; 
           [0032]      FIG. 4  is a section view illustrating the combined state of a printed circuit board, an interposer, a space transformer and a probe assembly employed in the probe card in accordance with one embodiment of the present invention; 
           [0033]      FIG. 5  is a front view schematically illustrating a probe of a probe assembly in accordance with one embodiment of the present invention; 
           [0034]      FIGS. 6A and 6B  are front views showing variants of a connection terminal portion employed in the probe of the probe assembly in accordance with one embodiment of the present invention; 
           [0035]      FIG. 7  is a section view depicting a process by which insertion slots are formed in a supporter of the probe assembly in accordance with one embodiment of the present invention; 
           [0036]      FIG. 8  is a section view schematically showing a part of a probe card in accordance with one embodiment of the present invention; and 
           [0037]      FIGS. 9   a,    9   b  and  9   c  are sectional views showing positional relationship between two slots. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0038]    Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
         [0039]    Referring to  FIG. 1 , a probe card  100  in accordance with one embodiment of the present invention includes a printed circuit board  110 , a plurality of interposers  120 , a plurality of space transformers  130  and a plurality of probe assemblies  140 . 
         [0040]    The printed circuit board  110  is connected to a test head of a tester (not shown) through a pogo block and a performance board unit, both of which are well-known in the art. A stiffener  101  for reinforcing the stiffness of the printed circuit board  110  is attached to the upper surface of the printed circuit board  110 . A stiffener cover  102  for protecting the stiffener  101  is fixed to the upper surface of the stiffener  101  and a plurality of handles  103  is attached to the upper surface of the stiffener cover  102 . 
         [0041]    The interposers  120  are attached to the lower surface of the printed circuit board  110  so that they can be connected to the printed circuit board  110 . The interposers  120  serve to transmit electric signals between the printed circuit board  110  and the probe assemblies  140  and also to maintain the planarity of the probe card  100 . 
         [0042]    The space transformers  130  are attached to the lower surfaces of the interposers  120  so that they can be connected to the interposers  120 . Each of the space transformers  130  is formed of a multi-layer printed circuit board  131  having a plurality of electrode pads  132  on the lower surface thereof. The electrode pads  132  are electrically connected to the printed circuit board  110  through the interposers  120 . Although the interposers  120  and the space transformers  130  are two in number in one embodiment shown in  FIG. 1 , the number of the interposers  120  and the space transformers  130  may be changed arbitrarily. 
         [0043]    Referring to  FIGS. 1 to 3 , each of the probe assemblies  140  includes a supporter  141  attached to the lower surface of the multi-layer printed circuit board  131  and a plurality of probes  161  fixed to the opposite side surfaces of the supporter  141 . The supporter  141  is made of an insulating material, e.g., a ceramic material such as zirconia (ZrO 2 ) or the like. 
         [0044]    As illustrated in  FIGS. 3 and 4 , the supporter  141  has first and second vertical side surfaces  142  and  143  formed on the opposite sides of the supporter  141 , a horizontal lower surface  146  formed on the underside of the supporter  141  and first and second slanting surfaces  144  and  145  for joining the first and second side surfaces  142  and  143  to the lower surface  146 . The first and second side surfaces  142  and  143  extend in a parallel relationship with each other. The first slanting surface  144  is formed between the first side surface  142  and the lower surface  146  and extends obliquely toward a center plane of the supporter  141  from the first side surface  142 . Similarly, the second slanting surface  145  is formed between the second side surface  143  and the lower surface  146  and extends obliquely toward a center plane of the supporter  141  from the second side surface  143 . A first channel  151  is formed in the middle region of the first slanting surface  144  to extend in a longitudinal direction. Likewise, a second channel  152  is formed in the middle region of the second slanting surface  145  to extend in the longitudinal direction. The first slanting surface  144  is divided by the first channel  151  into a first surface portion  144   a  (a first facing surface) joined to the first side surface  142  and a second surface portion  144   b  (an additional facing surface) joined to the lower surface  146 . Similarly, the second slanting surface  145  is divided by the second channel  152  into a first surface portion  145   a  joined to the second side surface  143  and a second surface portion  145   b  joined to the lower surface  146 . 
         [0045]    The supporter  141  has a plurality of first and second insertion slots  147  and  148  into which the probes  161  of a thin plate type are inserted. The first insertion slots  147  are formed on the first side surface  142  and the first slanting surface  144 . The second insertion slots  148  are formed on the second side surface  143  and the second slanting surface  145 . Each of the first insertion slots  147  consists of a first slot portion  147   a  formed on the first side surface  142 , a second slot portion  147   b  formed on the first surface portion  144   a  of the first slanting surface  144  and a third slot portion  147   c  formed on the second surface portion  144   b  of the first slanting surface  144 . The first, second and third slot portions  147   a,    147   b  and  147   c  lie on one and the same cross-sectional plane. Each of the second insertion slots  148  consists of a first slot portion  148   a  formed on the second side surface  143 , a second slot portion  148   b  formed on the first surface portion  145   a  of the second slanting surface  145  and a third slot portion  148   c  formed on the second surface portion  145   b  of the second slanting surface  145 . The first, second and third slot portions  148   a,    148   b  and  148   c  lie on the same cross-sectional plane. The first insertion slots  147  and the second insertion slots  148  lie on the same cross-sectional plane in a symmetrical relationship. Alternatively, the first insertion slots  147  and the second insertion slots  148  may lie on different cross-sectional planes. 
         [0046]    The first insertion slots  147  and the second insertion slots  148  are formed to extend across the lower surface  146  of the supporter  141 . This means that the first insertion slots  147  and the second insertion slots  148  are met with each other on the lower surface  146 . Needless to say, the first insertion slots  147  and the second insertion slots  148  are not met with each other on the first slanting surface  144  or the second slanting surface  145 . 
         [0047]    The supporter  141  is screw-fixed to the lower surface of the multi-layer printed circuit board  131 . For this purpose, a pair of thread holes  149  is formed in the opposite end portions of the supporter  141 . As can be seen in  FIG. 4 , the supporter  141  is fixed to the lower surface of the multi-layer printed circuit board  131  by driving a screw  153  into the corresponding one of the thread hole  149  through the multi-layer printed circuit board  131 . Although the supporter  141  is of an elongated bar shape in the illustrated embodiment, the width and length of the supporter  141  may be arbitrarily changed if such a need arises. For example, the supporter  141  may have a block shape or other shapes rather than the elongated bar shape. 
         [0048]    The thin plate type probes  161  are fitted to the first and second insertion slots  147  and  148  of the supporter  141 . As shown in  FIG. 4 , each of the probes  161  is designed to make contact with an electrode pad  132  of the multi-layer printed circuit board  131  at one end and with an electrode pad  11  of an inspection object  10  such as a wafer, a flat display or the like at the other end. Electric signals are transmitted between the multi-layer printed circuit board  131  and the inspection object  10  through the probes  161 . Each of the probes  161  includes a first arm portion  162 , a second arm portion  163 , a connection terminal portion  164  and a contact terminal portion  167 . The second arm portion  163  extends obliquely from the first arm portion  162  in a downward direction. 
         [0049]    As illustrated in  FIG. 5 , the connection terminal portion  164  is joined to the upper end of the first arm portion  162  so that it can be connected to the electrode pad  132  of the multi-layer printed circuit board  131 . The connection terminal portion  164  is formed of an elastically deformable spring portion  165  and a first terminal  166 . The spring portion  165  is connected to the upper end of the first arm portion  162  and is formed into a meandering shape so that it can be elastically deformed when compressed or pulled. The first terminal  166  is joined to the upper end of the spring portion  165  and is connected to the electrode pad  132  of the multi-layer printed circuit board  131 . In one embodiment of the present invention, the connection terminal portion  164  of each of the probes  161  may have many different shapes. 
         [0050]      FIGS. 6A and 6B  show variants of the connection terminal portion. A connection terminal portion  182  shown in  FIG. 6A  is joined to the upper end of a first arm portion  181 . The connection terminal portion  182  includes a pre-stressed and elongated spring portion  183  having a gently curved shape, and a first terminal  184  joined to the upper end of the spring portion  183 . The spring portion  183  is of a pre-stressed bending beam structure and has relatively high flexural stiffness, i.e., increased elastic strain and durability. Therefore, the spring portion  183  is prevented from being plastically deformed even when the first terminal  184  makes contact with the electrode pad  132  of the multi-layer printed circuit board  131  (see  FIG. 4 ) and receives a vertical load. When the first terminal  184  is connected to the electrode  132 , the spring portion  183  undergoes elastic deformation to thereby increase the contact area between the first terminal  184  and the electrode pad  132 . This makes it possible to assure stable connection between the first terminal  184  and the electrode pad  132 . 
         [0051]    A connection terminal portion  192  shown in  FIG. 6B  is formed of a spring band  193  and a first terminal  196 . The spring band  193  has a band portion  194  joined to the upper end of a first arm portion  191  and a plurality of holes  195  formed along the length of the band portion  194  at an equal interval. The opposite side surfaces of the band portion  194  are formed into an undulating shape to permit elastic deformation of the band portion  194 . If the first terminal  196  makes contact with the electrode pad  132  of the multi-layer printed circuit board  131  (see  FIG. 4 ) and receives a vertical load, the spring band  193  is compressed and elastically deformed. The first terminal  196  is maintained in close contact with the electrode pad  132  by the biasing force of the spring band  193 . 
         [0052]    Referring again to  FIGS. 4 and 5 , the contact terminal portion  167  of each of the probes  161  includes an elastic bar  168  and a second terminal  169 . The elastic bar  168  extends in an elongated shape from the tip end of the second arm portion  163  so that it can be elastically deformed. The second terminal  169  is formed in the tip end of the elastic bar  168  and is designed to make contact with the electrode pad  11  of the inspection object  10 . 
         [0053]    Each of the probes  161  includes a reinforcing portion  171  that reinforces the stiffness of the elastic bar  168 . The reinforcing portion  171  is formed of an extension portion  172  and a connection portion  173 . The extension portion  172  extends upwardly from the upper edge of the second arm portion  163 . The connection portion  173  serves to interconnect the intermediate portion of the elastic bar  168  and the upper surface of the extension portion  172 . The elastic bar  168 , the extension portion  172  and the connection portion  173  make a triangle when they are viewed from the front. As can be seen in  FIG. 4 , the reinforcing portion  171  of each of the probes  161  is positioned in the first channel  151  or the second channel  152  of the supporter  141 . 
         [0054]    In addition, each of the probes  161  has a first recess  174  and a second recess  175 . The first recess  174  is formed in an inner corner where the first arm portion  162  and the second arm portion  163  are met with each other. The second recess  175  is formed in an inner corner where the second arm portion  163  and the extension portion  172  are met with each other. Provision of the first and second recesses  174  and  175  in each of the probes  161  helps restrain stresses from being concentrated on the corner where the first arm portion  162  and the second arm portion  163  are met with each other and the corner where the second arm portion  163  and the extension portion  172  are met with each other. Otherwise, the stress concentration may occur in the manufacturing process of the probes  161 . Furthermore, the first and second recesses  174  and  175  serve to ensure that the probes  161  are accurately fitted to the supporter  141  even if a machining error exists in the supporter  141  or even when an assembly error is present between the supporter  141  and the probes  161 . 
         [0055]    As can be seen in  FIG. 4 , during the process of inserting the probes  161  into the first insertion slots  147  of the supporter  141 , the outer corner where the first side surface  142  and the first slanting surface  144  are met with each other is received in the first recess  174 , and the outer corner where the first surface portion  144   a  of the first slanting surface  144  and the first channel  151  are met with each other is received in the second recess  175 . This makes it possible to accurately insert the probes  161  into the first insertion slots  147 . Similarly, during the course of inserting the probes  161  into the second insertion slots  148  of the supporter  141 , the outer corner where the second side surface  143  and the second slanting surface  145  are met with each other is received in the first recess  174 , and the outer corner where the first surface portion  145   a  of the second slanting surface  145  and the first channel  151  are met with each other is received in the second recess  175 . This makes it possible to accurately insert the probes  161  into the second insertion slots  148 . 
         [0056]    The probes  161  configured as above are firmly fixed to the supporter  141  by means of an insulating resin material  154  such as epoxy resin or the like, after they have been inserted into the first and second insertion slots  147  and  148  of the supporter  141 . The probe assemblies  140 , each of which includes the supporter  141  and the probes  161 , are attached to the lower surface of the multi-layer printed circuit board  131 . For the purpose of protecting the probe assemblies  140  attached to the lower surface of the multi-layer printed circuit board  131 , a cover  104  is fixed to the lower surface of the printed circuit board  110  by a plurality of screws  105  as shown in  FIG. 1 . An opening  105  for receiving the probe assemblies  140  is formed in the central region of the cover  104 . 
         [0057]    Description will now be made on a process of manufacturing the probe card in accordance with one embodiment of the present invention. 
         [0058]    First, each of the probe assemblies  140  is produced by forming the first and second insertion slots  147  and  148  in the supporter  141  and fitting the probes  161  into the first and second insertion slots  147  and  148 . Referring to  FIG. 7 , the first and second insertion slots  147  and  148  are cut on the left and right sides of the supporter  141  by means of a wheel cutter  20  having a specified diameter (e.g., a diameter of 55.4 mm) at an equal or unequal interval. In this cutting process, the first insertion slots  147  are first cut on the first side surface  142  and the first slanting surface  144 , after which the second insertion slots  148  are cut on the second side surface  143  and the second slanting surface  145 . 
         [0059]    During the process of cutting the first and second insertion slots  147  and  148  on the first and second slanting surfaces  144  and  145 , the first and second insertion slots  147  and  148  may be formed to extend to the lower surface  146  of the supporter  141 . In this case, the first and second insertion slots  147  and  148  may be overlapped with each other on the lower surface  146 . The overlapping occurs only in the lower surface  146 . During the course of cutting the second insertion slots  148 , the wheel cutter  20  does not meet with the first insertion slots  147  previously formed on the first side surface  142  and the first slanting surface  144 . Therefore, it is possible to form the first and second insertion slots  147  and  148  on the left and right sides of the supporter  141  at a narrow interval with no likelihood of mutual interference. 
         [0060]    An insulating resin  154  is applied to the first and second insertion slots  147  and  148  formed in the supporter  141 . Then, the probes  161  are fitted into the first and second insertion slots  147  and  148  as illustrated in  FIGS. 3 and 4 , thereby completing a fabrication process of one of the probe assemblies  140 . At this time, the first arm portion  162  of each of the probes  161  is inserted into the first slot portion  147   a  of each of the first insertion slots  147 . The second arm portion  163  is inserted into the second slot portion  147   b  and the contact terminal portion  167  is inserted into the third slot portion  147   c.  The reinforcing portion  171  is positioned in the first channel  151 . Similarly, the first arm portion  162  of each of the probes  161  is inserted into the first slot portion  148   a  of each of the second insertion slots  148 . The second arm portion  163  is inserted into the second slot portion  148   b  and the contact terminal portion  167  is inserted into the third slot portion  148   c.  The reinforcing portion  171  is positioned in the second channel  152 . 
         [0061]    If the insulating resin  154  is completely cured after the probes  161  have been inserted into the first and second insertion slots  147  and  148 , the probes  161  are firmly fixed to the supporter  141  by the insulating resin  154 . In this manner, the probes  161  are inserted into the first and second insertion slots  147  and  148  formed at a narrow interval, whereby the arrangement interval of the probes  161  becomes narrow. This enables the probe assemblies  140  according to one embodiment of the present invention to test the inspection object  10  having a fine pattern. 
         [0062]    The insulating resin  154  for fixing the probes  161  to the supporter  141  in the fabricating process of the probe assemblies  140  may be applied to the probes  161  and not to the first and second insertion slots  147  and  148 . In other words, the insulating resin  154  may be applied to the first and second arm portions  162  and  163  of the probes  161  prior to inserting the probes  161  into the insertion slots  147  and  148 . This also makes it possible to firmly fix the probes  161  to the supporter  141 . 
         [0063]    The probe assembly  140  thus fabricated is fixed to the lower surface of the multi-layer printed circuit board  131  by tightening the screws  153  into the thread holes  149  of the supporter  141  through the multi-layer printed circuit board  131 . At this time, the connection terminal portions  164  of the probes  161  are brought into contact with the electrode pads  132  of the multi-layer printed circuit board  131 . If the first terminal  166  of each of the connection terminal portions  164  receives a vertical load by making contact with each of the electrode pads  132 , the spring portion  165  is elastically deformed so that the first terminal  166  can remain in close contact with each of the electrode pads  132  by means of the biasing force of the spring portion  165 . 
         [0064]    After the probe assemblies  140  have been fixed to the lower surface of the multi-layer printed circuit board  131 , the multi-layer printed circuit boards  131  are mounted to the interposers  120  attached to the lower surface of the printed circuit board  110 . Then, the cover for protecting the probe assemblies  140  is attached to the printed circuit board  110 . The stiffener  101  and the stiffener cover  102  are fixed to the upper surface of the printed circuit board  110  one above the other, thereby terminating the fabrication of the probe card  100 . 
         [0065]    Next, description will be made on how to test the inspection object with the probe card in accordance with one embodiment of the present invention. 
         [0066]    The probe card  100  in accordance with one embodiment of the present invention is installed on and connected to a test head. As the test head comes into operation, the second terminal  169  of each of the probes  161  makes contact with each of the electrode pads  11  of the inspection object  10  as illustrated in  FIG. 4 . If the second terminal  169  of each of the probes  161  receives a vertical load by coming into contact with each of the electrode pads  11 , the elastic bar  168  is elastically deformed to ensure that the second terminal  169  remains in close contact with each of the electrode pads  11  of the inspection object  10 . At this time, the connection portion  173  of the reinforcing portion  171  supports the intermediate portion of the elastic bar  168  to prevent the elastic bar  168  from undergoing plastic deformation. This helps increase the lifespan and reliability of the probes  161 . 
         [0067]    The elastic bar  168  of each of the probes  161  is inserted into and held in place by the third slot portion  147   c  of each of the first insertion slots  147  and the third slot portion  148   c  of each of the second insertion slots  148 . For this reason, the elastic bar  168  is less likely to undergo flexural deformation in a transverse direction of the third slot portion  147   c  or  148   c.  This ensures that the second terminal  169  makes accurate contact with each of the electrode pads  11  of the inspection object  10 , thereby greatly improving the reliability and repeatability of the test for the inspection object  10 . 
         [0068]    Once the second terminals  169  of the probes  161  come into contact with the electrode pads  11  of the inspection object  10 , electric signals are transmitted between the printed circuit board  110  and the inspection object  10  via the interposers  120 , the multi-layer printed circuit boards  131  and the probe assemblies  140 . In case the probes  161  are arranged with an increased density, the multi-layer printed circuit board  131  makes it easy for the inter-layer conductor circuit to interconnect the probes  161  and the printed circuit board  110 . Furthermore, the probe assemblies  140  can be arranged at a high density using a plurality of the interposers  120  and a plurality of the space transformers  130 . Therefore, the probe card  100  in accordance with one embodiment of the present invention is capable of inspecting a single sheet of wafer having a diameter of 200 mm or 300 mm by performing only one or two touchdown operation. This makes it possible to greatly increase the inspection speed of the inspection object  10 . 
         [0069]    With the probe card  100  in accordance with one embodiment of the present invention, the spring portions  165  of the probes  161  are elastically deformed to ensure that tight physical contact is maintained between the electrode pads  132  of the multi-layer printed circuit board  131  and the first terminals  166  of the probes  161 . This eliminates the need to solder the electrode pads  132  and the first terminals  166 , thus greatly improving the productivity and reliability of the probe card  100  as compared to the prior art. 
         [0070]    With the probe card  100  in accordance with one embodiment of the present invention, the probes  161  are fixed in place in a state that they are inserted into the first and second insertion slots  147  and  148  of the supporter  141 . This eliminates the need to use a jig which would otherwise be used in the prior art for fitting the probes  161  to the supporter  141 . Therefore, it is possible to fabricate the probe assemblies  140  with ease, which in turn greatly improves the productivity of the probe card  100 . 
         [0071]    The probe card  100  in accordance with one embodiment of the present invention is of a structure in which the probes  161  are inserted into the first and second insertion slots  147  and  148  of the insulating supporter  141 . This eliminates the need to coat the probes  161  with an insulating material, which assists in saving production costs and improving productivity. 
         [0072]    With the probe card  100  in accordance with one embodiment of the present invention, if an abnormality occurs in one of the probe assemblies  140 , it is possible to remove only the abnormal one and replace it with a new one in a simple manner. This makes it possible to sharply reduce the costs involved in maintenance and repair. 
         [0073]      FIG. 8  is a section view schematically showing a part of a probe card in accordance with one embodiment of the present invention. The probe card  200  shown in  FIG. 8  is the same in most configurations as the probe card  100  of the preceding embodiment, except that probe assemblies  220  are directly coupled to a printed circuit board  210  with no intervention of the interposers  120  (see  FIG. 1 ) and the space transformers  130  (see  FIG. 1 ). The printed circuit board  210  is provided with a plurality of electrode pads  211 . The probes  231  of the probe assemblies  220  have connection terminal portions  232  connected to electrode pads  211  of the printed circuit board  210 . Each of the probe assemblies  140  is fixed to the printed circuit board  210  by driving screws  223  into thread holes  222  of a supporter  221  through the printed circuit board  210 . The remaining configurations including the probe assemblies  140  are the same as those of the preceding embodiment and, therefore, no description will be made in that regard. 
         [0074]    Referring to  FIG. 9   a,  in one embodiment, the probe assembly comprises one of the plurality of first slots  147  which does not overlap any one of the plurality of second slots  148  when viewed in a direction perpendicular to the first side surface  142 . Referring to  FIG. 9   b,  in one embodiment, the probe assembly comprises one of the plurality of first slots  147 , which has a width that partially overlaps with a width of one of the plurality of second slots  148  when viewed in a direction perpendicular to the first side surface  142 . Referring to  FIG. 9   c,  in one embodiment, the probe assembly comprises one of the plurality of first slots  147  that substantially eclipses one of the plurality of second slots  148  when viewed in a direction perpendicular to the first side surface  142 . 
         [0075]    As described above, the probe card in accordance with one embodiment the present invention includes a plurality of probes arranged at a high density. This helps reduce the frequency of touchdown operations performed during the course of inspecting an inspection object, thereby greatly increasing the inspecting speed of the inspection object. 
         [0076]    Furthermore, the probe card in accordance with one embodiment the present invention is of a structure in which probes are inserted into insertion slots of an insulating supporter. Therefore, the probe card can be fabricated with ease and increased accuracy. It is also possible to manufacture the probe card with reduced production cost and greatly increased productivity. 
         [0077]    Moreover, the probe card in accordance with one embodiment the present invention is formed of individual probe assemblies that can be separated from a printed circuit board on a one-by-one basis. This makes it easy to replace a defective probe or a defective probe assembly, consequently reducing the costs involved in maintenance and repair. 
         [0078]    In addition, the probe card in accordance with one embodiment the present invention allows probes to be accurately connected to an inspection object and a printed circuit board with no likelihood of plastic deformation. Thus, the probe card can enjoy increased reliability and prolonged lifespan. 
         [0079]    The present invention is not limited to the embodiments shown and described hereinabove. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention defined in the claims.