Patent Publication Number: US-8109768-B2

Title: Connector and electronic component provided with same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Priority is claimed on Japanese Patent Application No. 2008-199654, filed Aug. 1, 2008, the content of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector. In particular, it relates to a connector that can achieve fine pitches and low contact resistance with a simple construction, and an electronic component provided with this connector. 
     2. Description of Related Art 
     Heretofore, techniques have been investigated by which an IC package, such as a CPU, an LSI, or the like is mounted on a printed circuit board via a socket, and a socket for installing, a CPU, such as an LGA package, a BGA package, or the like, is mounted on many mother boards of personal computers and servers. There has been yearly progress in the number of pins and speed of CPUs owing to improvements in their functions and performance, and corresponding measures have been taken by increasing the size of the packages and making them more finely pitched. Accompanying this, sockets are required that can deal with the number of pins, and at the same time deal with the increase in the amount of bending accompanying the size increase of the packages, and that can deal with the dispersion of the heights of the contact loads and/or the solder balls of the packages. Therefore, it is important to make the size of the socket contacts small, and it is desirable to ensure that the contacts between the IC pins and the sockets have an appropriate contact pressure. Furthermore, it is important that the contacts have low inductance at high speeds, and it is required that the contact resistance is low, and the allowable current is high, corresponding to the increase in current consumption due to the high speeds. 
     Mainstream sockets for current LGA packages have 400 to 800 pins with a pitch of approximately 1 mm. For example, as described in Patent Document 1 and Patent Document 2, a construction is used that is manufactured by folding a metal plate in a complex way in order to form a predetermined contact shape, and inserting the contact in a socket housing. 
     Such a method is a system in which an appropriate load is generated at a predetermined stroke by making the metal contact function as a spring in order to obtain a stable contact resistance. Moreover, in the process for obtaining a predetermined contact pressure, when the load is increased, the contact location is shifted so that a wiping effect can be expected whereby oxide film and/or contamination on the surface can be removed. 
     However, fine pitches are difficult to be achieved using these methods. When trying to achieve a fine pitch, it is necessary to shorten the length of the cantilevered part of the spring of a contact terminal. However, if the length of the spring is shortened, in the case of a cantilever spring with the same material and the same shape, the load required to obtain a predetermined stroke increases. Therefore, if the wire diameter (width and/or thickness) of the cantilever spring is reduced in order to generate the appropriate load, the permissible stress is required to be low, so in spite of the original intention of moving it in the elastic deformation zone, it undergoes plastic deformation, making it impossible to withstand a predetermined load. This is because the permissible stress is proportional to the wire diameter (width and/or thickness) of the spring, while the spring constant, which is the main factor for determining the load, is proportional to fourth power of the wire diameter (width and/or thickness) of the cantilever spring. 
     Considering this, instead of the method of obtaining a predetermined contact pressure due to the load of a cantilever spring, a technique has been devised in which the metal of the contact part is designed in a region where it undergoes plastic deformation, and the repulsion force is compensated by rubber or an elastomer. For example, in Patent Document 3, the function of the contact part is realized by flexible printed circuit boards, and a construction is disclosed in which the elastomer is sandwiched between two flexible printed circuit boards, and the flexible printed circuit boards are joined by soldering metal pins provided separately in order to obtain top to bottom interlayer conduction. 
     In this technique, metal domes are formed at the parts in contact with the flexible printed circuit boards, and the metal domes make contact with the facing contact points. Furthermore, if the load is increased in a process for obtaining a predetermined contact pressure, the contact locations shift, so that a wiping effect for removing oxide film and/or contamination from the surface can be expected. 
     Moreover, in Patent Document 4, a method is disclosed in which metal plating is applied to an elastomer in which predetermined dome shapes and through holes have been formed in advance by a metal mold, and a circuit is formed using a photolithographic process such that contacts are connected by the through holes and the domes. 
     However, as disclosed in Patent Document 3, the method in which the flexible printed circuit board is sandwiched by an elastomer requires a process for manufacturing two flexible printed circuit boards on which circuits are formed in required patterns, and furthermore, it requires metal contacts for obtaining interlayer conduction to connect them. Therefore, the number of parts is large, which makes it difficult to achieve miniaturization. Moreover, since a process is required for connecting the flexible printed circuit boards and the metal pins, there is a problem in that the manufacturing method becomes complex. Furthermore, as disclosed in Patent Document 4, there are still many areas for development in techniques for plating on elastomers, and there is a problem in that mass-production techniques have not been established in general. Moreover, in Patent Document 4, since contact pressure is obtained by the dome parts being deformed, the contact locations do not change, so that there is also a problem in that a wiping effect cannot be expected.
     [Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2004-158430   [Patent Document 2] Japanese Unexamined Patent Application, First Publication No. 2005-019284   [Patent Document 3] Japanese Unexamined Patent Application, First Publication No. 2004-071347   [Patent Document 4] Japanese Unexamined Patent Application, First Publication No. 2001-332321   

     BRIEF SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     The present invention has been made in view of the above circumstances, and therefore has an object to provide a connector that can achieve fine pitches and a reduction in contact resistance with a simple construction, and an electronic component provided with the same. 
     Means for Solving the Problem 
     (1) A connector of the present invention is characterized in that it is provided with: a molded base part having a substrate and elastomers arranged on both sides of the substrate; a plurality of through holes in the molded base part, which pass through the molded base part in a stacked direction of the substrate and the elastomers, and are arranged at predetermined spacing; and L-shaped contacts arranged via the through holes from one surface side of the molded base part to another surface side, wherein: the elastomers incorporate a plurality of first protruding parts whose top faces are inclined, and second protruding parts that protrude from top faces of the first protruding parts in a dome shape; said contact has dome shaped convex parts whose insides are hollow, and said convex parts are formed at two ends of the contact; and the convex parts are arranged such that they cover the respective second protruding parts. 
     (2) The connector of the present invention is characterized in that the first protruding parts, in (1), are arranged symmetrically about the substrate, and the second protruding parts are arranged symmetrically about the substrate. 
     (3) The connector of the present invention is characterized in that, in (1) or (2), the substrate is left exposed with no elastomers in the regions of the molded base part surrounding the through holes. 
     (4) An electronic component of the present invention is characterized in that it is provided with a connector according to any one of items (1) through to (3). 
     Effects of the Invention 
     According to the connector of the present invention, since it is possible to obtain predetermined load and displacement characteristics due to the elasticity of elastomers, the contacts are not required to have spring characteristics. Therefore it is possible to design without considering the permissible stress of the contacts, and hence a finer pitch is possible. Furthermore, in the connector of the present invention, when a load is applied to joining terminals of a semiconductor package or the like so that the convex parts of the contact make contact, the contact locations of the convex parts and the joining terminals shift during mounting. As a result, even in the case where oxide films, contamination, or the like are attached to the contact regions of the contacts and the joining terminals, it is possible to obtain contact on new areas by a wiping effect, so that the contact resistance can be reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a plan view showing schematically, an example of a connector according to a first embodiment of the present invention. 
         FIG. 1B  is a diagram showing schematically, a sectional view through L-L of  FIG. 1A . 
         FIG. 2A  contains a side view, a plan view and a rear view showing schematically, a contact used in the connector according to the first embodiment of the present invention. 
         FIG. 2B  is a cross-sectional view showing schematically, the contact used in the connector according to the first embodiment of the present invention. 
         FIG. 3A  is a sectional view showing schematically, a process for forming a plurality of through holes  4  in a substrate  1  in the connector according to the first embodiment of the present invention. 
         FIG. 3B  is a sectional view showing schematically, a process for mounting a metal mold  31  on the substrate  1  in the connector according to the first embodiment of the present invention. 
         FIG. 3C  is a sectional view showing schematically, a process for casting elastic material into cavities of the metal mold  31  in the connector according to the first embodiment of the present invention. 
         FIG. 3D  is a sectional view showing schematically, a process for removing the metal mold  31  from the substrate  1  in the connector according to the first embodiment of the present invention. 
         FIG. 3E  is a sectional view showing schematically, a process for deburring elastomers  2  using a punch  41  in the connector according to the first embodiment of the present invention. 
         FIG. 4A  is a sectional view showing schematically, a molded base part  3  in the connector according to the first embodiment of the present invention. 
         FIG. 4B  is a sectional view showing schematically, a process for inserting contacts  5  into through holes  4  of the molded base part  3  in the connector according to the first embodiment of the present invention. 
         FIG. 4C  is a sectional view showing schematically, a process for fitting the contacts  5  into the molded base part  3  in the connector according to the first embodiment of the present invention. 
         FIG. 4D  is a sectional view showing schematically, an example of a process for manufacturing contacts in the connector according to the first embodiment of the present invention. 
         FIG. 5  is a diagram showing schematically, a method for manufacturing contacts in the connector according to the first embodiment of the present invention. 
         FIG. 6A  is a sectional view showing schematically, an electronic component  80  in which a semiconductor package  60  and a circuit board  70  are connected electrically using the connector according to the first embodiment of the present invention. 
         FIG. 6B  is a sectional view showing schematically, a state in which a load is applied to the electronic component  80 . 
         FIG. 7A  is a plan view showing schematically, an example of a connector according to a second embodiment of the present invention. 
         FIG. 7B  is a sectional view through L-L of  FIG. 7A . 
         FIG. 8A  contains a side view, a plan view, and a rear view, showing schematically, a contact used in the connector according to the second embodiment of the present invention. 
         FIG. 8B  is a cross-sectional view showing schematically, the contact used in the connector according to the second embodiment of the present invention. 
         FIG. 9A  is a sectional view showing schematically, a process for forming a plurality of through holes  4  in a substrate  1  in the connector according to the second embodiment of the present invention. 
         FIG. 9B  is a sectional view showing schematically, a process for mounting a metal mold  31  on the substrate  1  in the connector according to the second embodiment of the present invention. 
         FIG. 9C  is a sectional view showing schematically, a process for casting elastic material into cavities of the metal mold  31  in the connector according to the second embodiment of the present invention. 
         FIG. 9D  is a sectional view showing schematically, a process for removing the metal  31  from the substrate  1  in the connector according to the second embodiment of the present invention. 
         FIG. 9E  is a sectional view showing schematically, a process for deburring elastomers  2  using a punch  41  in the connector according to the second embodiment of the present invention. 
         FIG. 10A  is a sectional view showing schematically, a molded base part  3  in the connector according to the second embodiment of the present invention. 
         FIG. 10B  is a sectional view showing schematically, a process for inserting contacts  5  into through holes  4  of the molded base part  3  in the connector according to the second embodiment of the present invention. 
         FIG. 10C  is a sectional view showing schematically, a process for fitting the contacts  5  into the molded base part  3  in the connector according to the second embodiment of the present invention. 
         FIG. 10D  is a sectional view showing schematically, an example of a process for manufacturing contacts in the connector according to the second embodiment of the present invention. 
         FIG. 11  is a diagram showing schematically, a method for manufacturing contacts in the connector according to the second embodiment of the present invention. 
         FIG. 12A  is a sectional view showing schematically, an electronic component  90  in which a semiconductor  60  and a circuit board  70  are connected electronically using the connector according to the second embodiment of the present invention. 
         FIG. 12B  is a sectional view showing schematically, a state in which a load is applied to the electronic component  90 . 
     
    
    
     BRIEF DESCRIPTION OF THE REFERENCE SYMBOLS 
     
         
           1  Substrate 
           2  ( 2 A,  2 B) Elastomer 
           3  Molded base part 
           4  Through hole 
           5  Contact 
           10  ( 10 A,  10 B) Connector 
           21  ( 21 A,  21 B) First protruding part 
           21   s  Top face of first protruding part 
           22  ( 22 A,  22 B) Second protruding part 
           23  Burr 
           31  Metal mold 
           32  Cavity 
           33  Parting line 
           41  Punch 
           50  Hoop 
           51  ( 51 A,  51 B) Convex part of contact 
           60  Semiconductor package 
           61  Joining terminal 
           70  Circuit board 
           71  Joining terminal 
           80 ,  90  Electronic component 
         α Solderbump 
       
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereunder is a detailed description of the present invention, with reference to the drawings. However, the present invention is not limited to this, and various modifications are possible provided they do not depart from the gist of the present invention. 
     First Embodiment 
       FIG. 1A  and  FIG. 1B  are diagrams showing schematically, a connector  10 A according to a first embodiment of the present invention.  FIG. 1A  is a plan view, and  FIG. 1B  is a diagram showing schematically, a sectional view through L-L of  FIG. 1A . 
     The connector  10 A of the present invention comprises, in general: a molded base part  3  comprising a substrate  1  and elastomers  2  ( 2 A,  2 B) arranged on the two surfaces  1   a  and  1   b  of the substrate  1 ; a plurality of through holes  4  in the molded base part  3 , which pass through the molded base part  3  in the stacked direction of the substrate  1  and the elastomers  2 , and are arranged in parallel at predetermined spacing; and L-shaped contacts  5  arranged via the through holes  4  from one surface  3   a  of the molded base part  3  to the other surface  3   b . Furthermore, a plurality of first protruding parts  21  ( 21 A,  21 B) whose top faces  21   s  are inclined, and second protruding parts  22  ( 22 A,  22 B), which protrude from the top faces  21   s  of the first protruding parts  21  in a dome shape, are arranged on the elastomers  2 . Dome shaped convex parts  51  ( 51 A,  51 B) whose insides are hollow are formed at the two ends  5   a  and  5   b  ( FIG. 2A ,  2 B) of the contacts  5 , and the convex parts  51  are arranged such that they cover the respective second protruding parts  22 . Hereunder is a detailed description of the connector  10 A. 
     The substrate  1  is a insulator flat board, and the elastomers  2  ( 2 A,  2 B) are arranged on its two surfaces  1   a  and  1   b , forming a molded base part  3 . For the substrate  1 , a flexible material, such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulphone (PES), polyimide, polyamide imide, polyetherimide, or the like, and glass epoxy, liquid crystal polymer (LCP), or the like, can be given as examples. The thickness is greater than or equal to 25 μm and less than or equal to 2000 μm, for example. 
     For the elastomers  2  ( 2 A,  2 B), natural rubber, latex, isobutylene-isoprene rubber, silicone rubber, fluoride rubber, perfluoroether rubber, or the like can be given as examples. Appropriate choice is possible depending on the elasticity and characteristics required for a connector. That is, by adjusting the dimensions and the material of the elastomers  2 , it is possible to control the load and displacement characteristics of the connector  10 A of the present invention. By using the elastomers  2 , there is no need for the contact  5  to have spring characteristics, so there is no limitation to the permissible stress of the contact  5 , and it is possible to handle fine pitches. 
     The elastomers  2 A arranged on the one surface  1   a  of the substrate  1  and the elastomers  2 B arranged on the other surface  1   b  of the substrate  1  may be formed from the same type of material, or may be formed from different materials and have different elasticity. 
     Furthermore, on the one surface  1   a  and the other surface  1   b  of the substrate  1 , there are no elastomers  2  arranged on the peripheries of the through holes  4 , giving regions  1   c  where the substrate  1  is exposed. In this manner, by having the regions  1   c  where the substrate  1  is exposed, it is possible to achieve an improvement in the productivity of the manufacturing process as described later. 
     The first protruding parts  21  are formed from the same material as the elastomers  2 , and are arranged on the two faces  2   a  and  2   b  of the elastomers  2  at predetermined spacing. The top faces  21   s  of the first protruding parts are sloped. The one end  5   a  and the other end  5   b  of each of the contacts  5  are placed along the slope. By the top faces  21   s  sloping, it is possible to gain height from the molded base part  3  to the top points of the second protruding parts  22 , so that the operable stroke range when a load is applied to the contacts  5  can be designed to be wide. The angle of the slope and the direction of the slope of the top faces  21   s  may be the same for each of the first protruding parts  21 , or may vary. Moreover, they may be the same on the one surface  1   a  side and the other surface  2   b  side of the substrate  1 , or may be different. The angle of the slope and the direction of the slope can be adjusted appropriately depending on a conductive substrate connected electrically with the connector  10 A of the present invention. 
     The heights of the first protruding parts  21  from the elastomers  2  may be the same for each of the first protruding parts  21 , or may vary. Furthermore, they may be the same on the one surface  1   a  side and the other surface  1   b  side of the substrate  1 , or may be different. The heights of each of the first protruding parts  21  can be adjusted appropriately according to the heights of the joining terminals of a conductive substrate connected electrically with the connector  10 A of the present invention. 
     If the heights of each of the first protruding parts  21  are the same and the angles of the slopes of each of the top faces  21   s  are the same, it is possible to control the predetermined load and displacement characteristics easily. 
     The second protruding parts  22  ( 22 A,  22 B) are formed from the same material as the elastomers  2 , are arranged on the top faces  21   s  of the first protruding parts  21 , and are dome shaped. Convex parts  51  ( 51 A,  51 B), which are hollow and dome shaped, are formed at the two ends  5   a  and  5   b  of the contact  5  ( FIG. 2A ,  FIG. 2B ). The surface of the second protruding part  22  is shaped such that it matches the convex part  51  of the contact  5 . The size of the second protruding part  22  can be adjusted appropriately according to the pitch of the contact  5 . 
     For the shape of the second protruding part  22 , it may also be a round column, a polygonal column such as a triangular column or a quadrangular column, a cone, or a polygonal pyramid such as a triangular pyramid or a quadrangular pyramid. 
     It is preferable that the first protruding parts  21  are arranged symmetrically about the substrate  1  between the one surface  1   a  side and the other surface  1   b  side of the substrate  1 . Furthermore, it is preferable that the second protruding parts  22  are arranged symmetrically about the substrate  1  between the one surface  1   a  side and the other surface  1   b  side of the substrate  1 . By the first protruding parts  21  and the second protruding parts  22  being arranged symmetrically about the substrate  1 , when the connector  10 A of the present invention is connected to another conductive substrate or the like electrically with sufficient contact pressure, the contact pressure is applied to the same regions from the one surface  1   a  side and the other surface  1   b  side of the substrate  1 . As a result, it is possible to prevent deformation of the substrate  1  occurring due to the stress caused by the contacts, as much as possible. 
     A plurality of through holes  4  is provided in the molded base part  3  at predetermined spacing, passing through the molded base part  3  in the thickness direction (stacked direction of the substrate  1  and the elastomers  2 ) of the molded base part  3 . The size and shape of the through holes  4  is not specifically limited provided the contacts  5  can be inserted. Here, the predetermined spacing means greater than or equal to 0.3 mm and less than or equal to 2.5 mm, for example. 
     The contacts  5  are installed such that they are fed from the one surface  3   a  to the other surface  3   b  of the molded base part  3  via the through holes  4 , and are designed for electrical conduction between the conductive substrate arranged on the one surface  3   a  of the molded base part  3  and the conductive substrate arranged on the other surface  3   b  of the molded base part  3 . The contact  5  is L-shaped with the central part of the contact  5  bent at an angle of θ 1  degrees as shown in  FIG. 2A  and  FIG. 2B , and dome shaped convex parts  51  ( 51 A,  51 B) whose insides are hollow are formed on its two ends  5   a  and  5   b .  FIG. 2A  is a side view, a plan view, and a rear view of the contact  5 , and  FIG. 2B  is a cross-sectional view. 
     For a material for forming the contact  5 , copper, an alloy containing copper, or the like, are given as examples. The thickness may be such that it does not deform when mounted with a load applied to a semiconductor package or the like, and may be greater than or equal to 10 μm and less than or equal to 100 μm, for example. Moreover, the width of the contact  5  can be adjusted appropriately according to the conductivity or the like required for the connector, and may be greater than or equal to 100 μm and less than or equal to 1000 μm, for example. By using metal as the contact  5 , it can be plated so that it is possible to reduce the contact resistance when it is electrically connected with the joining terminal of the conductive substrate. In particular, by performing plating using the same type of metal as the joining terminal, it is possible to further reduce the contact resistance. 
     In the construction of the present invention, in the case where copper is used as the contact  5 , for example, if the thickness is greater than or equal to 20 μm, a design is possible whereby even if a load of 50 gf is applied, it is not deformed due to the elasticity of the rubber (elasticity of the elastomers  2 , the first protruding part  21 , and the second protruding part  22 ). 
     For example, in the case where contact points of 1 mm pitch are formed in the connector  10 , a design is possible with the width of the contact  5  being 0.5 mm, and the radius of the dome of the convex part  51  being 0.25 mm. There is a tendency that, for the same contact thickness, the strength increases as the diameter of the dome reduces, so in the case of finer pitches, the thickness of the metal may be smaller. According to the present invention, it is possible to realize 0.3 mm pitch to 1.0 mm pitch. 
     According to the connector  10 A of the present invention, there is no limitation to the permissible stress on the contact  5  itself, and even if the thickness and width are such that it undergoes plastic deformation, it is possible to obtain predetermined load and displacement characteristics due to the elasticity of the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22 . Fine pitches, such as 0.3 mm pitch to 1.0 mm pitch for example, are possible. Moreover, by selection of the dimensions and material of the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22 , it is possible to control the load of the connector  10 A and the displacement characteristics. Furthermore, since the contacts  5  are made of metal, low contact resistance can be achieved by plating. Moreover, since the connector comprises the substrate  1 , the elastomers  2 , the first protruding parts  21 , the second protruding parts  22 , and the contacts  5 , and since the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  can be molded collectively, it is possible to reduce the number of parts, enabling it to be miniaturized and to be manufactured easily, so that it is possible to reduce the cost and improve the yield. 
     &lt;Manufacturing Method&gt; 
       FIG. 3A  to  FIG. 3E  and  FIG. 4A  to  FIG. 4D  are sectional views showing schematically, an example of a method of manufacturing the connector  10 A of the present invention. 
     Firstly, as shown in  FIG. 3A , a plurality of through holes  4  is formed in predetermined locations of the substrate  1  using machining or perforating by laser. 
     Next, as shown in  FIG. 3B  and  FIG. 3C , the substrate  1  is mounted in a metal mold  31 , elastic material of the elastomers  2 , the first protruding part  21   s , and the second protruding parts  22 , is casted into the cavity  32  of the metal mold  31  by pouring or injection, and the metal mold  31  is heated up to vulcanizing temperature for molding. The metal mold  31  is not especially defined, so a conventionally known one can be used. 
     Since the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  are arranged on the substrate  1  by pouring or injection using the metal mold  31 , the elastomers  2 , the plurality of the first protruding parts  21  and the second protruding parts  22  can be formed on the two surfaces  1   a  and  1   b  of the substrate  1  collectively, so that it is possible to improve the work efficiency and the yield. Furthermore, since the elastomers  2  are arranged over the whole area of the one surface  1   a  of the substrate  1  excluding the peripheral parts  1   c  of the through holes  4 , the first protruding parts  21  are not isolated on the substrate  1 . Therefore, it is possible to provide a sprue hole (not shown in the figure) through which material is injected when forming the elastomers  2 , in a free place of the metal mold  31 . 
     Next, as shown in  FIG. 3D , the metal mold  31  is removed. In the case where burrs  23  occur in the through holes  4 , the burrs of the elastomers  2  are removed by punches  41  or the like as shown in  FIG. 3E . 
     At this time, as shown in  FIG. 3B  and  FIG. 3C , it is preferable for the parting line  33  of the metal mold  31  to be set so as to give the thickness part of the substrate  1 . Even in the case where burrs  23  occur as shown in  FIG. 3D , the burrs  23  are not joined to the elastomers  2  formed on the substrate  1 , and they make contact only with the inner wall surfaces  4   a  of the through holes  4  of the substrate  1 , so that it is possible to remove just the burrs  23  easily. 
     Next, as shown in  FIG. 4A  and  FIG. 4B , the contacts  5  are inserted into the through holes  4  of the molded base part  3  manufactured in  FIG. 3D . 
     Regarding the manufacturing of the contacts  5 , by press molding a metal plate in a series, it is possible to mold it in a hoop shape as shown in  FIG. 5 . If a process using a V groove β is applied at the breaks between the hoop  50  and the contacts  5 , it is possible to separate each of the contacts  5  from the hoop  50  in an intended process easily. 
     Furthermore, conventionally, the surfaces of the parts (corresponding to the convex parts  51 A and  51 B) that make contact with the joining terminals of the conductive substrate are gold plated over a nickel-plated base. However, in the case of a hoop shape with such a configuration as shown in  FIG. 5 , it is possible to dip only the convex parts  51 A and  51 B and the two ends  5   a  and  5   b  of the contacts  5  in a plating bath  55 . As a result, there is no need to plate unnecessary parts of the contacts  5 , so that inexpensive nickel plating and gold plating are possible. 
     Regarding the contacts  5  manufactured in this manner, it is preferable that the L-shaped angle θ 2  is made to be a shape opened sufficiently more widely than the angle θ 1  of the final shape such that it is easy to insert the contacts  5  into the through holes  4  to mount the convex parts  51  on the second protruding parts  22 . 
     Next, as shown in  FIG. 4C , the angles θ 2  of the contacts  5  are reduced, and are bent such that the insides of the dome shaped convex parts  51 A and  51 B formed on the respective two ends  5   a  and  5   b  of the contacts  5  are fitted to the respective second protruding parts  22 A and  22 B. 
     By the above, as shown in  FIG. 4D , the connector  10 A according to the first embodiment of the present invention can be obtained. 
     According to the method of manufacturing a connector  10 A of the present invention, since the first protruding parts  21  and the second protruding parts  22  are not independent, but are connected to the elastomers  2 , it is possible to form them together. 
     Therefore, the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  can be formed on the substrate  1  simultaneously, and hence the manufacturing process can be simplified. Furthermore, it is possible to fit the contacts  5  into the molded base part  3  easily. 
     &lt;Electronic Component&gt; 
       FIG. 6A  and  FIG. 6B  are schematic diagrams of an electronic component  80  in which a semiconductor package  60  and a circuit board  70  are electrically connected, for example, using a connector  10 A of the present embodiment.  FIG. 6A  shows a state in which the contacts  5  are connected with joining terminals  61  arranged on the semiconductor package  60  and joining terminals  71  arranged on the circuit board  70 .  FIG. 6B  is a sectional view showing schematically, the state after a load is applied after the state of  FIG. 6A . 
     The broken line in the drawing is a line passing through the contacts of the convex parts  51  of the contacts  5  and the joining terminals  61  and  71 . 
     The semiconductor package  60  and the circuit board  70  are not especially defined, so commonly known ones can be used. 
     When the semiconductor package  60  and the circuit board  70  are connected electrically using the connector  10 A of the present embodiment, the elastomers  2  undergoes elastic deformation, so the angle θ 1  of the contacts  5  becomes θ 3 , which is a smaller angle. At this time, it is possible for the connector  10 A, the semiconductor package  60 , and the circuit board  70  to be mounted by appropriate contact pressure due to the stress created by elastic deformation. Moreover, as shown in  FIG. 6A  and  FIG. 6B , the contacts of the contacts  5  and the joining terminals  61  shift when load is applied. Therefore, even in the case where foreign substances, oxide films, or the like are attached to the contact surfaces of the joining terminals  61  and  71  and the contacts  5 , it is possible to obtain contact on new areas in the contact regions of both of the joining terminals  61  of the semiconductor package  60  and the joining terminals  71  of the circuit board  70  by a wiping effect, so that the resistance can be reduced. 
     Second Embodiment 
       FIG. 7A  and  FIG. 7B  show, schematically, a connector  10 B according to a second embodiment of the present invention. 
       FIG. 7A  is a plan view, and  FIG. 7B  is a sectional view through L-L of  FIG. 7A . The same reference symbols are used as for the same elements of the first embodiment, and the descriptions are sometimes omitted. 
     The point of difference between the connector  10 B of the present embodiment and the connector  10 A of the first embodiment is that the first protruding parts  21 A, the second protruding parts  22 A, and the elastomers  2  are arranged on only the one surface  1   a  of the substrate  1 . In this manner, in the present invention, the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  may be arranged on only the one surface  1   a  of the substrate  1  according to the electronic component, or the like, that is employed. At this time, as shown in  FIG. 8A  and  FIG. 8B , a solder bump α is provided on the other end  5   b  of the contact  5 , and the contact  5  is connected to another conductive substrate or the like electrically via the solder bump α. 
     According to the connector  10 B of the present embodiment, when contact is made with another conductive substrate on the one surface  1   a  of the substrate  1 , the stroke amount can be adjusted, so that it is possible to mount it with an appropriate contact pressure. Furthermore, it is possible to make it smaller than the connector  10 A of the first embodiment. 
     &lt;Manufacturing Method&gt; 
       FIG. 9A  to  FIG. 9E  and  FIG. 10A  to  FIG. 10D  are sectional views showing schematically, an example of a method for manufacturing the connector  10 B according to the present embodiment. 
     Firstly, as shown in  FIG. 9A , similarly to the connector  10 A of the first embodiment, through holes  4  are formed at predetermined spacing. 
     Next, as shown in  FIG. 9B  and  FIG. 9C , the substrate  1  is mounted in a metal mold  31 , elastic material of the elastomers  2  is casted into the cavity  32  of the metal mold  31  by pouring or injection, and the metal mold  31  is heated up to vulcanizing temperature for molding. The metal mold  31  is not especially defined, so a conventionally known one can be used. 
     Since the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  are arranged on the one surface  1   a  of the substrate  1  by pouring or injection using the metal mold  31 , the plurality of first protruding parts  21  and second protruding parts  22 , which are formed on the elastomers  2  can be formed on the one surface  1   a  of the substrate  1  collectively, so that it is possible to improve the work efficiency and the yield. Furthermore, since the elastomers  2  are arranged on the whole area of the one surface  1   a  of the substrate  1  excluding the peripheral parts  1   c  of the through holes  4 , the first protruding parts  21  are not isolated on the substrate  1 . Therefore, it is possible to provide a sprue hole (not shown in the figure) through which material is injected when forming the elastomers  2 , in a free place of the metal mold  31 . 
     Next, as shown in  FIG. 9D , the metal mold  31  is removed. In the case where burrs  23  occur in the through holes  4 , the burrs of the elastomers  2  are removed by punches  41  or the like as shown in  FIG. 9E . 
     At this time, it is preferable for the parting line  33  of the metal mold  31  to be set so as to give the thickness part of the substrate  1 . Even in the case where burrs  23  occur as shown in  FIG. 9D , the burrs  23  are not joined to the elastomers  2  on the substrate  1 , and they make contact with the inner wall surfaces  4   a  of the through holes  4  formed in the substrate  1 , so that it is possible to remove them easily. 
     Next, as shown in  FIG. 10A  to  FIG. 10E , the contacts  5  are inserted into the through holes  4  of the molded base part  3  manufactured in  FIG. 9D . 
     Regarding the manufacturing of the contacts  5 , by press molding a metal plate in a series, it is possible to mold it in a hoop shape as shown in  FIG. 11 . If a process using a V groove ρ is applied at the breaks between a hoop  50  and the contacts  5 , it is possible to separate each of the contacts  5  from the hoop  50  in an intended process. 
     Furthermore, conventionally, the surfaces of the parts that make contact with the joining terminals of the conductive substrate are gold plated over a nickel base. However, in the case of a hoop shape with such a configuration as shown in  FIG. 11 , it is possible to dip only the dome shaped convex parts  51 A and the other ends  5   b  of the contacts  5  in a plating bath  55 . As a result, there is no need to plate unnecessary parts, so that inexpensive nickel plating and gold plating are possible. 
     Regarding the contacts  5  manufactured in this manner, it is preferable that the L-shaped angle θ 2  is made to be a shape opened sufficiently more widely than the angle θ 1  of the final shape such that it is easy to insert the contacts  5  into the through holes  4  to mount the convex parts  51 A on the second protruding parts  22 A. 
     Next, as shown in  FIG. 10C , the angles θ 2  of the contacts  5  are reduced, and are bent such that the insides of the dome shaped convex parts  51 A arranged on the one end  5   a  of each of the contacts  5  are fitted to the second protruding parts  22 A. 
     By the above, as shown in  FIG. 10D , the connector  10 B according to the second embodiment of the present invention can be obtained. 
     According to the method of manufacturing a connector  10 B of the present invention, the elastomers  2 , the first protruding parts  21 A, and the second protruding parts  22 A can be formed on the one surface  1   a  of the substrate  1  together, and hence the manufacturing process can be simplified. Furthermore, it is possible to fit the contacts  5  into the molded base part  3  easily. 
     &lt;Electronic Component&gt; 
       FIG. 12A  and  FIG. 12B  are diagrams showing schematically, an example of an electronic component  90  in which a semiconductor package  60  and a circuit board  70  are electrically connected, for example, using a connector  10 B of the present embodiment.  FIG. 12A  shows a state in which the contacts  5 , and joining terminals  61  provided on the semiconductor package  60 , and joining terminals  71  arranged on the circuit board  70  are connected.  FIG. 12B  is a sectional view showing schematically, the state after a load is applied after the state of  FIG. 12A . The connector  10 B and the circuit board  70  are connected electrically via the solder bumps α arranged on the other ends  5   b  of the contacts  5 . After the connector  10 B is mounted on the circuit board  70  and the solder bumps α are reflowed, it can be connected electrically with the semiconductor package  60  by applying a load. 
     By applying a load, the elastomers  2  undergo elastic deformation, and the angle θ 1  of the contacts  5  becomes θ 3 , which is a smaller angle. At this time, it is possible for the connector  10 B and the semiconductor package to be mounted by appropriate contact pressure due to the stress created by elastic deformation. Moreover, the broken line in the drawing is a line passing through the contacts between the convex parts  51  of the contacts  5  and the joining terminals  61 , and the contacts between the solder bumps α of the contacts  5  and the joining terminals  71 . However, by applying the load, the contacts have shifted. Therefore, even in the case where contamination, oxide films, or the like are attached to the contact surfaces of the joining terminals  61  and the contacts  5 , it is possible to obtain contacts on new areas in the contact regions of the semiconductor package  60  and the joining terminals  61  by a wiping effect, so that the resistance can be reduced. Furthermore, since the elastomers  2 , the first protruding parts  21 , and the second protruding parts  22  are arranged on only the one surface  1   a  of the substrate  1 , it is possible to achieve greater miniaturization of the electronic component  90  using the connector  10 B of the second embodiment, than the electronic component  80  using the connector  10 A of the first embodiment. 
     INDUSTRIAL APPLICABILITY 
     It is possible to use a connector of the present invention for an IC socket used when mounting an IC package such as a CPU, LSI, or the like on a printed circuit board, and to achieve fine pitches and a reduction in contact resistance, which is useful for industry. 
     While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.