FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to the data processing field, and more particularly, relates to a method and structures for implementing angled interposer interconnect systems. 
       DESCRIPTION OF THE RELATED ART 
       [0002]    Most interconnect systems facilitate 0, 90 or 180 degree interconnection. As mechanical packaging requirements become more aggressive interconnections at various non standard angles are needed. Specific 22 degree angled connectors are available for dual inline memory module (DIMM) applications. 
       SUMMARY OF THE INVENTION 
       [0003]    Principal aspects of the present invention are to provide a method and structures for implementing angled interposer interconnect systems. Other important aspects of the present invention are to provide such method and structures substantially without negative effects and to overcome many of the disadvantages of prior art arrangements. 
         [0004]    In brief, a method and structures are provided for implementing angled interposer interconnect systems. The angled interposer interconnect systems include an angled interconnect having a selected interconnect angle including a plurality of land grid array (LGA) contacts. The selected interconnect angle is provided within a predefined range between zero degrees one hundred eighty (180) degrees. Selected connector LGA contacts have substantially matching length for enhanced signal integrity performance. 
         [0005]    In accordance with features of the invention, modified bolsters are provided with the land grid array (LGA) contacts. 
         [0006]    In accordance with features of the invention, the angled interposer interconnect systems enable enhanced flexibility in mechanical design. 
         [0007]    In accordance with features of the invention, the angled interposer interconnect systems enable enhanced heat transfer to ambient air. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present invention together with the above and other objects and advantages may best be understood from the following detailed description of the preferred embodiments of the invention illustrated in the drawings, wherein: 
           [0009]      FIG. 1  schematically illustrates not to scale an example structure for implementing angled interposer interconnect systems in accordance with the preferred embodiment; 
           [0010]      FIG. 2  schematically illustrates not to scale an example contact structure for implementing angled interposer interconnect systems in accordance with the preferred embodiment; 
           [0011]      FIGS. 3A and 3B  schematically illustrate not to scale respective example structure for implementing angled interposer interconnect systems in accordance with the preferred embodiment; 
           [0012]      FIG. 4  schematically illustrates an example pre-form enabling 90 degree connector with constant LGA contact length in accordance with the preferred embodiment; 
           [0013]      FIG. 5  schematically illustrates an example 90 degree connector with different length LGA in accordance with the preferred embodiment; 
           [0014]      FIG. 6  schematically illustrates not to scale an example structure for implementing modular connector concept to customize angled interposer interconnect systems in accordance with the preferred embodiment; 
           [0015]      FIG. 7  schematically illustrates not to scale an example structure for implementing angled interposer interconnect systems in accordance with the preferred embodiment; and 
           [0016]      FIG. 8  schematically illustrates not to scale an example hybrid pre-form for implementing angled interposer interconnect systems in accordance with the preferred embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0017]    In the following detailed description of embodiments of the invention, reference is made to the accompanying drawings, which illustrate example embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention. 
         [0018]    The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
         [0019]    In accordance with features of the invention, a method and structures are provided for implementing angled interposer interconnect systems, enabling enhanced flexibility in mechanical design. Additional angled connector systems are needed to meet packaging challenges. Interconnects that match lengths are needed to improve signal integrity performance. 
         [0020]    Having reference now to the drawings, in  FIG. 1 , there is shown an example structure generally designated by the reference character  100  for implementing angled interposer interconnect systems in accordance with preferred embodiments. 
         [0021]    In accordance with features of the invention, the structure or angled interposer interconnect system  100  includes an interposer carrier  102  that is sized and arranged for providing a selected low angle connection to be positioned between a first board or chip  104  and a second board or chip  106 , as shown. The interposer carrier  102  includes a plurality of different length contacts  110  allowing for the angled connection system  100 . A screw force indicated by a respective arrow labeled SCREW FORCE A, SCREW FORCE B, respectively is applied to the first board or chip  104  and the second board or chip  106 . As illustrated by an arrow C, optional offset contact points or LGA contact contour or interposer contour design provide normal force with low angled applications. 
         [0022]    Referring now to  FIG. 2 , there is schematically shown an example contact structure generally designated by the reference character  200  for implementing angled interposer interconnect systems in accordance with the preferred embodiment. The contact structure  200  includes modified contacts indicated by labels: S 1 , S 2 , G 3 , S 4 , S 5 , G 6 , S 7 , S 8 , and G 9  with an angle of 10 degrees. The contact structure  200  is used for a  3  pair differential connector with a signal, signal, ground configuration of S 1 , S 2 , G 3 , S 4 , S 5 , G 6 , S 7 , S 8 , and G 9 . The modified contacts include a pair matching contact length for signals pairs S 1  and S 2 ; S 4  and S 5 ; and S 7  and S 8 . For example, as shown in the following Table A: 
         [0000]                                TABLE A                       Unmatched lengths   Matched lengths                           S1 52.9   53.3           S2 53.3   53.3           G3 53.6   53.6           S4 54.0   54.3           S5 54.3   54.3           G6 54.7   54.7           S7 55.0   55.4           S8 55.4   55.4           G9 55.7   57.4                        
As shown, the first pair S 1 , S 2  to the last pair S 7 , S 8  matching contact length differential is 2.5 mm (98 mils). As shown, matching length is achieved within the first pair S 1 , S 2 , within the second pair S 4 , S 5  and within the third pair S 7 , S 8 .
 
         [0023]    Referring now to  FIGS. 3A and 3B , there is schematically shown respective example structure respectively generally designated by the reference character  300 ,  310  for implementing angled interposer interconnect systems in accordance with the preferred embodiment. Each of the structures or angled interposer interconnect systems  300 ,  310  includes the interposer carrier  102  providing a selected low angle connection positioned between the first board or chip  104  and the second board or chip  106 . The interposer carrier  102  includes the plurality of different length contacts  110  allowing for the angled connection system  100 . 
         [0024]    As shown in  FIGS. 3A and 3B , an additional integrated bolster  302 ,  312 , respectively provided with the interposer carrier  102 . A material gradient in the integrated bolster  302 ,  312  can assist in offsetting unmatched contact lengths. 
         [0025]    Referring now to  FIG. 4 , there is schematically shown an example pre-form structure generally designated by the reference character  400  enabling 90 degree connector with constant LGA contact length in accordance with the preferred embodiment. The pre-form structure  400  includes an integrated pre-form  402  with an area  404  indicated in dotted line that is available for 1) within connector length matching; 2) system length matching; 3) signal crossing; and 4) active and passive components including redrive, filters, power conversion and the like. The pre-form structure  400  is used with a first board or chip  406  and a second board or chip  408  cooperating with respective pre-form structure cooperating portions  410 ,  412 . 
         [0026]    Referring now to  FIG. 5 , there is schematically shown an example 90 degree connector with different length LGA generally designated by the reference character  500  in accordance with the preferred embodiment. The 90 degree connector  500  includes an interposer carrier  502  used with a first board or chip  506  and a second board or chip  508 . The 90 degree connector  500  includes a respective clearance opening  510  for receiving different length LGA contacts. Each respective clearance opening  510  includes an angled connection portion  512 . 
         [0027]    Referring now to  FIG. 6 , there is schematically shown an example modular connector structure generally designated by the reference character  600  for implementing modular connector concept to customize angled interposer interconnect systems in accordance with the preferred embodiment. Modular connector structure  600  illustrates example customized connector features of Power, Standard, Standard, Matched Length, Standard, and Filtered Signals. 
         [0028]    Referring now to  FIG. 7 , there is schematically shown an example structure generally designated by the reference character  700  for implementing angled interposer interconnect systems with variable LGA contact length in accordance with the preferred embodiment. The angled connector  700  includes an interposer carrier  702  used with a first board or chip  706  and a second board or chip  708 . The angled connector  700  includes a respective clearance opening  710  for receiving different length LGA contacts. Each respective clearance opening  710  includes an angled connection portion  712 . 
         [0029]    Referring now to  FIG. 8 , there is schematically shown an example hybrid pre-form generally designated by the reference character  800  for implementing angled interposer interconnect systems in accordance with the preferred embodiment. The pre-form  800  includes an interposer carrier  802  used with a fixed first board or chip  806  and a second board or chip  808  receiving a screw force indicated by an arrow SCREW FORCE, and including includes a respective clearance opening  810  for receiving different length LGA contacts. Each respective clearance opening  810  includes an angled connection portion  812 . 
         [0030]    While the present invention has been described with reference to the details of the embodiments of the invention shown in the drawing, these details are not intended to limit the scope of the invention as claimed in the appended claims.
A method and structures are provided for implementing angled interposer interconnect systems. The angled interposer interconnect systems include an angled interconnect having a selected interconnect angle including a plurality of land grid array (LGA) contacts. The selected interconnect angle is provided in a provided within a predefined range between zero degrees one hundred eighty (180) degrees. Selected connector LGA contacts have substantially matching length for enhanced signal integrity performance.