Abstract:
The invention provides an interconnecting assembly including a main structure having first and second portions, an inner terminal on the main structure, a support film having first and second portions, an inner contact and outer terminal formed on opposing sides of the support film, a conductive lever portion on the support film and connecting the inner contact and outer terminal, wherein the inner contact contacts the inner terminal and the first portions are moved relatively towards one another so that the second portion of the film is pivoted together with the conductive lever portion and the outer terminal away from the second portion of the main structure, the outer terminal being depressible towards the main structure from a first position to a second position and returning to the first position when a force depressing the outer terminal is removed.

Description:
BACKGROUND OF THE INVENTION 
     1). Field of the Invention 
     This invention relates generally to an interconnecting assembly and more specifically to an interposer. 
     2). Discussion of Related Art 
     Integrated circuits are formed on semiconductor wafers. The wafers are then sawed (or “singulated” or “diced”) to microelectronic dies, also known as semiconductor chips, with each chip carrying a respective integrated circuit. Each semiconductor chip is then mounted to a package, or carrier substrate, thereby forming an electronic package or a semiconductor package. The packages are temporarily connected to test sockets so that the integrated circuit can be tested before it is sold. The package is then mounted to a printed circuit board, which may then be installed into a computing system. 
     Interposers are often used during testing to ensure the electrical connection between the test socket and the package, as well as between the printed circuit board and the package. Such an interposer typically has a substrate with via holes therethrough and vias within the via holes to electrically connect the package to either the test socket or the printed circuit board. Springs can then be connected to the vias and the springs ensure uniform contact when they are depressed by contacts on the package or a printed circuit board. 
     If more range is required in a direction that the spring is compressed, then pogo pins are often used. The pogo pin is held between two halves of a substrate. Opposing ends of the pogo pin protrude through openings in the two halves. Such an interposer can be expensive because pogo pins themselves are expensive and the assembly methods that may be required are labor intensive. 
     SUMMARY OF THE INVENTION 
     The invention provides an interconnecting assembly including a main structure having first and second portions, an inner terminal on the main structure, a support film having first and second portions, an inner contact and outer terminal formed on opposing sides of the support film, a conductive lever portion on the support film and connecting the inner contact and outer terminal, wherein the inner contact contacts the inner terminal and the first portions are moved relatively towards one another so that the second portion of the film is pivoted together with the conductive lever portion and the outer terminal away from the second portion of the main structure, the outer terminal being depressible towards the main structure from a first position to a second position and returning to the first position when a force depressing the outer terminal is removed. 
     The interconnecting assembly may further include an adhesive between the first portions to attach the first portion to one another. 
     The interconnecting assembly may further include a metal support on the support film, the adhesive attaching both the metal support and the first portion of the support film to the main structure, the first portion of the support film being depressed in an area between the metal support and the inner terminal. 
     The interconnecting assembly may include that the inner contact and the inner terminal form an interference fit. 
     The interconnecting assembly may further include an outer via connecting the conductive lever portion to the outer terminal. 
     The interconnecting assembly may further include a plurality of inner contacts and outer terminals formed on the opposing sides of the support film, and a plurality of lever portions on the support film and connecting a respective one of the inner contacts on a respective one of the outer contacts. 
     The interconnecting assembly may further include a plurality of inner terminals, wherein each inner contact contacts a respective inner terminal and the first and second portions are moved relatively towards one another so that the second portion of the film is pivoted together with the conductive portions and the outer terminals away from the second portions of the main structure. 
     The invention also provides a method of making an interconnect assembly, including positioning an inner contact on an inner terminal, moving a first portion of a support film on which the inner contact is formed relatively towards a first portion of a main structure on which the inner terminal is formed so that a second portion of a the film pivots together with an outer terminal and a conductive lever portion connecting the outer terminal to the inner contact away from a second portion of the main structure and attaching the first portions to one another. 
     The method may include that the first portions may be attached by an adhesive. 
     The method may further include simultaneously applying heat and pressure to the adhesive to soften the adhesive and allowing the adhesive to cool. 
     The method may include that the pressure may be applied with a shaping tool, further including securing the shaping tool t the main structure before allowing the adhesive to cool and removing the shaping tool from the main structure after the adhesive is allowed to cool. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is further described by way of example with reference to the accompanying drawings, wherein: 
         FIG. 1  is cross-sectional side view showing upper and lower shaping tools and components of an interconnecting assembly in the form of an interposer before the interposer is assembled; 
         FIG. 2  is a view similar to  FIG. 1  after heat and pressure are applied to the shaping tools; 
         FIG. 3  is a view similar to  FIG. 2  after a heat chuck is removed and the upper and lower shaping tools are secured to one another with a bolt and a nut; 
         FIG. 4  is a view similar to  FIG. 3  after the bolt, nut and upper and lower shaping tools are removed and the interposer is used to connect contacts of devices to one another; 
         FIG. 5  is a top plan view of one support film showing multiple outer contacts; and 
         FIG. 6  is a bottom view of the support film of  FIG. 5 , showing multiple conductive lever portions and inner contacts. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  of the accompanying drawings illustrates upper and lower shaping tools  10 U and  10 L and an interconnecting assembly in the form of an interposer  12 . 
     The interposer  12  includes a supporting substrate  14 , an upper adhesive layer  16 U, a lower adhesive layer  16 L, an upper interconnect structure  18 U and a lower interconnect structure  18 L. 
     The supporting substrate  14  includes a main structure  20 , upper and lower inner terminals  22 U and  22 L, and an inner via  24 . The main structure  20  has an upper surface with first and second portions  26  and  28 . The main structure  20  is made of an insulative material. The inner via  24  is in an opening of the main structure  20  extending from the upper surface of the main structure  20  to a lower surface of the main structure  20  in an area between the first portion  26  and the second portion  28 . The upper inner terminal  22 U is formed on the upper surface of the main structure  20 . The upper inner terminal  22 U is structurally connected to the inner via  24  and is larger than the inner via  24 . The upper inner terminal  22 U forms a step  30  above the first portion  26 . 
     Similarly, the lower inner terminal  22 L is formed on the lower surface of the main structure  20  and is structurally connected to the inner via  24 . 
     The upper and lower inner terminals  22 U and  22 L and the inner via  24  are all made of a conductive metal. Electric current can thus conduct through the inner via  24  between the upper and lower inner terminals  22 U and  22 L. 
     The upper interconnect structure  18 U has a support film  32 , a metal support  34 , an inner contact  36 , a conductive lever portion  38 , an outer via  40 , and an outer terminal  42 . 
     The support film  32  has first and second portions  44  and  46  and is made of a compliant, flexible, resilient, springable insulating material. The outer terminal  42  is formed on an upper surface of the second portion  46  of the support film  32 . The outer via  40  is formed through and opening in the second portion  46  of the support film  32  and is structurally connected to the outer terminal  42 . The conductive lever portion  38  and the inner contact  36  are formed on a lower surface of the second portion  46  of the support film  32 . The outer via  40  is structurally connected to the conductive lever portion  38 . The inner contact  36  and the outer terminal  42  have conductive particles formed thereon. The conductive particles may for example be metal-covered diamond particles. 
     The metal support  34  is formed on a lower surface of the support film  32 . The metal support  34  and the inner contact  36  form steps  48  and  50 , respectively, below a lower surface of the support film  32  in an area of the first portion  44 . 
     The adhesive layer  16 U is provided in the form of a sheet that does not have any adhesive qualities at room temperature. The upper adhesive layer  16 U is positioned above the first portion  26  of the main structure  20 . The upper interconnect structure  18 U is positioned over the main structure  20  and the upper adhesive layer  16 U such that the inner contact  36  is aligned with and above the inner terminal  22 U. A recess formed between the steps  48  and  50  is located to the left of the upper inner terminal  22 U and the second portion  46  of the support film  32  is positioned to the right of the upper inner terminal  22 U. 
     The upper shaping tool  10 U has a protrusion  60  that is positioned above the recess between the steps  48  and  50 . The upper shaping tool  10 U has recesses  62  and  64  to the left and the right of the protrusion  60 . A step  66  formed by the recess  62  is larger than a step  68  formed by the recess  64 . 
     The lower interconnect structure  18 L, lower adhesive layer  16 L and the lower shaping tool  10 L are a mirror image of the upper interconnect structure  18 U, upper adhesive layer  16 U and the upper shaping tool  10 U. Like reference numerals indicate like or similar components. Manufacturing of the interposer  12  will now further be described with reference to the upper interconnect structure  18 U, upper adhesive layers  16 U and the upper shaping tool  10 U. It should be understood that the manufacturing of the interposer  12  with respect to the lower interconnect structure  18 L, lower adhesive layer  16 L and lower shaping tool  10 L is similar. 
     Reference is now made to  FIG. 2 . An upper heat chuck  70 U is located against an upper surface of the upper shaping tool  10 U. A heater such as a heating element  72  within the upper heat chuck  70 U is used to heat the upper shaping tool  10 U. The upper heat chuck  70 U is then used to apply pressure to the upper shaping tool  10 U. A lower surface of the protrusion  60  makes contact with the first portion  44  of the support film  32 . Heat conducts from the protrusion  60  through the first portion  44  to the upper adhesive layer  16 U, causing the upper adhesive layer  16 U to soften. The upper adhesive layer  16 U then fills spaces between the metal support  34 , the first portion  44  of the support film  32  and the first portion  26  of the main structure  20 . 
     The softening of the upper adhesive layer  16 U and the pressure provided by the protrusion  60  causes the protrusion  60  to depress the first portion  44  of the support film  32  into the recess between the steps  48  and  50 . The inner contact  36  provides a pivot point on the upper inner terminal  22 U so that the second portion  46  of the support film  32  pivots upwardly, counterclockwise away from the second portion  28  of the main structure  20 . The pressure provided by the protrusion  60  also causes an interference fit between the inner contact  36  and the upper inner terminal  22 U. The conductive lever portion  38  and the outer terminal  42  pivot together with the second portion  46  of the support film  32  away from the main structure  20 . The recess  64  is deep enough so as not to restrict pivoting of the second portion  46  of the support film  32  away from the main structure  20 . 
     Referring to  FIG. 3 , the upper and lower shaping tools  10 U and  10 L have aligned openings  72 . A bolt  74  and a nut  76  are provided to secure the upper and lower shaping tools  10 U and  10 L to one another, and therefore to the supporting substrate  14 . The bolt  74  has a shank  78  and a head  80 . The shank  78  is inserted through the openings  72  and the head  80  rests on an upper surface of the upper shaping tool  10 U. The nut  76  is screwed onto thread  82  on the shank  78  and rests against a lower surface of the lower shaping tool  10 L. The entire assembly shown in  FIG. 3  is then allowed to cool to room temperature. Although passive cooling is described wherein the assembly of  FIG. 3  cools in air at room temperature, it is to be understood that active cooling such as with cold water is also within the scope of the invention and that the assembly can also be allowed to cool with active cooling. 
     Once the assembly has cooled, the upper and lower adhesive layers  16 U and  16 L have again solidified and have adhered to all adjacent components. The nut  76  is then removed from the bolt  74  and the bolt  74  is removed from the openings  72 . The upper and lower shaping tools  10 U and  10 L are then removed from the interposer  12 . 
       FIG. 4  shows the use of the interposer  12  to provide an electric connection between a device such as a socket  100  and a device such as an electronics wireframe package  102 . The socket  100  has a substrate  104  and a contact  106 . The electronics wireframe package  102  has one or more substrates  108 , a semiconductor chip  109  on the substrate  108  and a contact  110  on the semiconductor chip  109 . The contacts  106  and  110  are aligned with the outer terminals  42 . A force is then applied that moves the electronics wireframe package  102  towards the socket  100 . The contacts  110  and  106  move the outer terminals  42  relatively towards one another. The material of the support films  32  and the conductive lever portions  38  are sufficiently flexible so that they bend to allow for movement of the outer terminals  42  towards the main structure  20 , and to return to their original positions as shown in  FIG. 3  when the force is removed. The amount of deflection provided by the support films  32  is equivalent to that of a pogo pin having a length similar to a distance between contacting surfaces of the outer terminals  42 . 
       FIG. 5  shows further details of one of the support films  32 . The support film  32  has a plurality of cutouts  112  formed therein, each corresponding to a respective semiconductor chip. A plurality of outer terminals  42  are formed along a periphery of a respective cutout  112 . Each cutout  112  has four main sides and a plurality of the outer terminals  42  are formed along a respective side of the cutout  112 . As shown in  FIG. 6 , a plurality of conductive lever portions  38  are formed along a respective side of each cutout  112 . It will be understood that each one of the outer terminals  42  make contact with a respective contact such as the contact  110  on a device. Similarly, inner terminal  36  is connected to a respective inner contact such as the upper inner terminal  22 U shown in  FIG. 2 . 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative and not restrictive of the current invention, and that this invention is not restricted to the specific constructions and arrangements shown and described since modifications may occur to those ordinarily skilled in the art.