Method and apparatus for electrical and mechanical attachment, and electromagnetic interference and thermal management of high speed, high density VLSI modules

• US 6,198,630 B1
• Filed: 01/20/1999
• Issued: 03/06/2001
• Est. Priority Date: 01/20/1999
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Cromwell, S. Daniel
• Primary Examiner(s): Picard, Leo
• Assistant Examiner(s): Datskovsky, Michael
• Application Number:
  US09/234,127
• Time in Patent Office: 776 Days
• Field of Search: 361/690-695, 361/818, 361/688, 361/697, 361/718-720, 361/816, 361/699, 361/700-710, 361/712-717, 361/802-803, 257/706-727, 174/15.1, 174/16.3, 174/252, 174/52.4, 174/35.R, 165/80.3, 165/80.4, 165/185, 439/526, 439/71, 439/79, 439/73, 439/66
• US Class Current: 361/704
• CPC Class Codes: H01L 23/4006 with bolts or screws
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 7/1431 Retention mechanisms for CPU modules

Abstract

A method and apparatus for assembling a high speed, high density VLSI module in a computer system that enables attachment, support, electromagnetic interference containment, and thermal management of the VLSI module. The present invention packages a high speed, high density VLSI module within a limited space and in a single assembly that attaches, aligns, and manages electromagnetic interference and heat dissipation of the VLSI module. The present invention aligns a land grid array of a circuit board and an interposer socket assembly, and the interposer socket assembly and a land grid array of the VLSI module; in the single VLSI module assembly. An even, controlled load is placed on the interposer socket interface thereby reducing the risk of damage to the interposer socket from overloaded connections between the land grid array of the VLSI module, the interposer socket assembly, and the land grid array of the circuit board. The present invention is easy-to-use in upgrading and handling of the VLSI module.

Claims

1. A VLSI module assembly comprising:

a circuit board including a land grid array;

a VLSI module for electrical connection to said circuit board, said VLSI module being a land grid array;

an alignment frame attached to said circuit board, said alignment frame circumscribing and enclosing the sides of said VLSI module;

a load spreader connected to said VLSI module and aligned to said alignment frame thereby loading said VLSI module for electrical connection to said circuit board;

an overhead clamp, functioning as a spring, attached to said load spreader with pressure that applies load to said load spreader and to said VLSI module thereby electrically connecting said land grid array of said VLSI module to said land grid array of said circuit board; and

a heat sink screw attached to said overhead clamp, and connected to said load spreader thereby evenly applying load to said VLSI module.

2. The VLSI module assembly as set forth in claim 1, wherein said load spreader includes a heat sink so that said VLSI module thermally couples to said heat sink with a sufficiently low resistance thermal path.

3. The VLSI module assembly as set forth in claim 2, wherein said heat sink further includes a heat sink base, and at least one heat fin attached to said heat sink base thereby transferring heat from said VLSI module to said heat sink base and said heat fin.

4. The VLSI module assembly as set forth in claim 1, further comprising:

a pair of electromagnetic interference gaskets that attenuates electromagnetic interference from said VLSI module, said pair of electromagnetic interference gaskets being disposed between said alignment frame and said circuit board and between said alignment frame and said load spreader, a first one of said electromagnetic interference gaskets disposed between said alignment frame and said heat sink being molded into a groove in said alignment frame;

wherein said alignment frame includes electrically conductive material and said circuit board includes a ground plane;

said circuit board being attached to said alignment frame thereby attenuating electromagnetic interference from said VLSI module; and

said load spreader being connected to said VLSI module and said alignment frame thereby attenuating electromagnetic interference from said VLSI module.

6. The VLSI module assembly as set forth in claim 1, further comprising an interposer socket assembly attached to said circuit board, and aligned and connected to said VLSI module thereby facilitating electrical connection of said VLSI module to said circuit board.

7. The VLSI module assembly as set forth in claim 6, wherein said heat sink screw evenly applies load to said VLSI module and to said interposer socket assembly thereby electrically connecting, without overload, said VLSI module and said interposer socket to said circuit board.

5. A VLSI module assembly comprising:

a circuit board;

a VLSI module being soldered to said circuit board;

an alignment frame shaped to circumscribe and enclose the sides of said VLSI module;

a heat sink aligned to said alignment frame; and

an overhead clamp attached to said heat sink and to said alignment frame, then said alignment frame being attached to said circuit board, thereby connecting said heat sink to said soldered VLSI module and absorbing heat from said soldered VLSI module by said heat sink; and

a pair of electromagnetic interference gaskets that attenuates electromagnetic interference from said VLSI module, said pair of electromagnetic interference gaskets being disposed between said alignment frame and said circuit board and between said alignment frame and said heat sink, a first one of said electromagnetic interference gaskets disposed between said alignment frame and said heat sink being molded into a groove in said alignment frame.

8. A VLSI module assembly comprising:

a circuit board including a ground plane and a land grid array;

a VLSI module for electrical connection to said circuit board, said VLSI module being a land grid array;

an alignment flame attached to said circuit board, said alignment frame circumscribing and enclosing the sides of said VLSI module, and including electrically conductive material thereby attenuating electromagnetic interference from said VLSI module;

a heat sink connected to said VLSI module and aligned and connected to said alignment frame;

thereby loading said VLSI module for electrical connection to said circuit board, thermally coupling said VLSI module to said heat sink with a sufficiently low resistance thermal path, and attenuating electromagnetic interference from said VLSI module;

a pair of electromagnetic interference gaskets that attenuates electromagnetic interference from said VLSI module, said pair of electromagnetic interference gaskets being disposed between said alignment frame and said circuit board and between said alignment frame and said heat sink;

an interposer socket assembly attached to said circuit board, and aligned and connected to said VLSI module thereby facilitating electrical coupling of said VLSI module to said circuit board;

an overhead clamp, functioning as a spring, attached to said heat sink with pressure that applies load to said heat sink and to said VLSI module; and

a heat sink screw attached to said overhead clamp, and connected to said heat sink and evenly applying load to said VLSI module and to said interposer socket assembly thereby electrically connecting, without overload, said VLSI module and said interposer socket to said circuit board.

9. A method for creating a VLSI module assembly for a computer system, said computer system having a circuit board including a land grid array and a land grid array VLSI module, said method comprising:

attaching an alignment frame to said circuit board and circumscribing and enclosing the sides of said VLSI module;

connecting a load spreader to said VLSI module and aligning said load spreader to said alignment frame thereby loading said VLSI module for electrical connection to said circuit board;

attaching an overhead clamp, functioning as a spring, to said load spreader with pressure that applies load to said load spreader and to said VLSI module thereby electrically connecting said VLSI module to said circuit board; and

attaching a heat sink screw to said overhead clamp, and connecting said heat sink screw to said load spreader thereby evenly applying load to said VLSI module.

10. The method as set forth in claim 9, wherein connecting said load spreader step further includes substituting said load spreader with a heat sink and thermally coupling said heat sink to said VLSI module with a sufficiently low resistance thermal path.

11. The method as set forth in claim 9, further comprising:

sandwiching a pair of electromagnetic interference gaskets between said alignment frame and said circuit board and between said alignment frame and said load spreader thereby attenuating electromagnetic interference from said VLSI module, a first one of said electromagnetic interference gaskets disposed between said alignment frame and said heat sink being molded into a groove in said alignment frame;

attaching said alignment frame to said circuit board, wherein said alignment frame includes electrically conductive material and said circuit board includes a ground plane, thereby attenuating electromagnetic interference from said VLSI module; and

connecting said load spreader to said VLSI module and said alignment frame thereby attenuating electromagnetic interference from said VLSI module.

13. The method as set forth in claim 9, further comprising attaching an interposer socket assembly to said circuit board, and aligning and connecting said interposer socket assembly to said VLSI module thereby facilitating electrical connection of said VLSI module to said circuit board.

14. The method set forth in claim 13, wherein said attaching a heat sink screw to said overhead clamp, and connecting said heat sink screw to said load spreader evenly applies load to said VLSI module and to said interposer socket assembly thereby electrically connecting, without overload, said VLSI module and said interposer socket to said circuit board.

12. A method for creating a VLSI module assembly for a computer system, said computer system having a circuit board and a VLSI module, said method comprising:

mounting said VLSI module to said circuit board;

installing an alignment frame to circumscribe and enclose the sides of said VLSI module;

aligning a heat sink to said alignment frame;

attaching an overhead clamp to said heat sink and to said alignment frame, then attaching said alignment frame to said circuit board, thereby connecting said heat sink to said mounted VLSI module and absorbing heat from said mounted VLSI module by said heat sink; and

sandwiching a pair of electromagnetic interference gaskets between said alignment frame and said circuit board and between said alignment frame and said heat sink thereby attenuating electromagnetic interference from said VLSI module, a first one of said electromagnetic interference gaskets disposed between said alignment frame and said heat sink being molded into a groove in said alignment frame.