Optical information processing circuit assembly

• US 20040114851A1
• Filed: 12/12/2002
• Published: 06/17/2004
• Est. Priority Date: 12/12/2002
• Status: Active Grant

• Current Assignee: Aptiv Technologies Limited (Aptiv PLC)
• Original Assignee: Delphi Technologies, Inc. (Aptiv PLC)
• Inventors: Pan, Binghua, Burns, Jeffrey H., Troxell, John R., Chan, Su Liang, Tan, Tecktiong, Chaudhuri, Arun K.
• Granted Patent: US 7,324,715 B2
• Time in Patent Office: Days
• US Class Current: 385/14
• CPC Class Codes: G02B 6/4232 using the surface tension of fluid solder to align the elements, e.g. solder bump techniques flip-chip mounting techniques in assembly of semiconductor devices H01L24/81

Abstract

An optical information processing circuit assembly includes an optically transmissive substrate and a resiliently compressible circuit member affixed to the substrate and defining an opening therethrough with a number of leads disposed about the opening. An integrated imaging circuit defines a corresponding number of pads wherein the pads align with and electrically contact the leads. An optically transmissive medium may be disposed between and in contact with the substrate and the integrated imaging circuit to allow light transmission therethrough from the substrate to the imaging circuit. In one embodiment, resilient bumps are provided between the integrated imaging circuit and the resiliently compressible circuit member to form the electrical connection therebetween. Alternatively, solder bumps may replace the resilient bumps. Additional circuit components may be similarly mounted to the resiliently compressible circuit member to complete the assembly.

Claims

1. An optical information processing circuit assembly, the assembly comprising:

a first optically transmissive substrate;

a resiliently compressible circuit member affixed to said first substrate and defining a first opening therethrough with a number of electrically conductive leads disposed about said first opening; and

an integrated circuit having a surface defining a number of electrically conductive pads disposed about an imaging circuit, each of said number of electrically conductive pads electrically contacting corresponding ones of said number of electrically conductive leads with said surface of said integrated circuit facing said first substrate through said first opening defined through said resiliently compressible circuit member.

2. The circuit assembly of claim 1 further including an optically transmissive medium disposed between and in contact with said first substrate and said surface of said integrated circuit, said medium allowing light transmission therethrough from said first substrate to said imaging circuit.

3. The assembly of claim 2 wherein said first substrate defines a first refractive index and said surface of said integrated circuit defines a second refractive index;

and wherein said optically transmissive medium is configured to match said first refractive index to said second refractive index.

4. The assembly of claim 2 wherein said optically transmissive medium is a formable medium that, when set, bonds said surface of said integrated circuit to said resiliently compressible circuit member and to said first substrate.

5. The assembly of claim 4 further including a resilient bump disposed between each of said number of electrically conductive pads and said corresponding ones of said number of electrically conductive leads.

6. The assembly of claim 5 wherein said optically transmissive medium is set while said resilient bumps are under compression so that each of said resilient bumps maintains electrical contact between a corresponding electrically conductive pad and electrically conductive lead when said compression is thereafter removed.

7. The assembly of claim 6 wherein said optically transmissive medium is an electrically non-conductive paste.

8. The assembly of claim 3 further including a solder bump disposed between each of said number of electrically conductive pads and said corresponding ones of said number of electrically conductive leads.

9. The assembly of claim 8 said optically transmissive medium is set while said solder bumps are reflowed to electrically and mechanically connect each of said number of electrically conductive pads to said corresponding ones of said electrically conductive leads.

10. The assembly of claim 8 wherein said solder bumps are reflowed to electrically and mechanically connected each of number of electrically conductive pads to said corresponding ones of said electrically conductive leads

and wherein said optically transmissive medium is provided between said first substrate and said surface of said integrated circuit after said solder bumps are reflowed.

11. The assembly of claim 1 wherein said first substrate defines a top surface and an opposite bottom surface;

and wherein said resiliently compressible circuit member is flexible and a first portion of said resiliently compressible circuit member defining said first opening therethrough is affixed to said top surface of said first substrate, and a second portion of said resiliently compressible circuit member is affixed to said bottom surface of said first substrate, one of said first and second portions of said resiliently compressible circuit member extending away from said first substrate and defining thereon an electrical connection structure.

12. The assembly of claim 11 wherein said second portion of said resiliently compressible circuit member defines a second opening therethrough to said bottom surface of said first substrate, said second opening aligned with said first opening defined through said first portion of said resiliently compressible circuit member;

and wherein the assembly further includes a lens housing mounted to said bottom surface of said first substrate through said second opening, said lens housing carrying at least one optical or compound lens configured to focus light through said first substrate to said imaging circuit.

13. The assembly of claim 12 further including a number of additional circuit components mounted to said resiliently compressible circuit member;

wherein said imaging circuit, said number of additional circuit components and said electrical connection structure are all electrically interconnected to form the optical image processing circuit.

14. The assembly of claim 1 wherein said first substrate defines a top surface and an opposite bottom surface;

and wherein a first portion of said resiliently compressible circuit member defining said first opening therethrough is affixed to said top surface of said first substrate.

15. The assembly of claim 14 further including a lens housing mounted to said bottom surface of said first substrate and aligned with said first opening, said lens housing carrying at least one optical or compound lens configured to focus light through said first substrate to said imaging circuit.

16. The assembly of claim 15 wherein said resiliently compressible circuit member is flexible;

and further including a second substrate having a second portion of said resiliently compressible circuit member affixed thereto, one of said first and second portions of said resiliently compressible circuit member extending away from a corresponding one of said first and second substrates and defining thereon an electrical connection structure.

17. The assembly of claim 16 wherein said second portion of said resiliently compressible circuit member includes a first number of additional circuit components mounted thereto;

wherein said imaging circuit, said first number of additional circuit components and said electrical connection structure are all electrically interconnected to form the optical image processing circuit.

18. The assembly of claim 17 further including a third substrate having a third portion of said resiliently compressible circuit member affixed thereto;

and wherein said third portion of said resiliently compressible circuit member includes a second number of additional circuit components mounted thereto;

wherein said imaging circuit, said first and second number of additional circuit components and said electrical connection structure are all electrically interconnected to form the optical image processing circuit.

19. The assembly of claim 18 wherein said first, second and third substrates are affixed to a camera housing.

20. A method of assembling an optical information processing circuit, the method comprising the steps of:

providing an optically transmissive substrate;

affixing a resiliently compressible circuit member to one side of said substrate, said resiliently compressible circuit member defining an opening therethrough with a number of electrically conductive leads disposed about said opening;

dispensing a formable optically transmissive medium onto said substrate through said opening and onto said resiliently compressible circuit member adjacent to said opening;

aligning a number of electrically conductive pads defined on one surface of an integrated imaging circuit with corresponding ones of said number of electrically conductive leads, each of said number of electrically conductive pads having a resilient bump affixed thereto;

embedding said integrated imaging circuit into said formable optically transmissive medium and applying heat and compression to said integrated imaging circuit to compress said resilient bumps onto said electrically conductive leads; and

curing said formable optically transmissive medium while said integrated imaging circuit is under compression until said formable optically transmissive medium bonds to said substrate, said resiliently compressible circuit member and said integrated imaging circuit.

21. A method of assembling an optical information processing circuit, the method comprising the steps of:

providing an optically transmissive substrate;

affixing a resiliently compressible circuit member to one side of said substrate, said resiliently compressible circuit member defining an opening therethrough with a number of electrically conductive leads disposed about said opening;

dispensing a formable optically transmissive medium onto said substrate through said opening and onto said resiliently compressible circuit member adjacent to said opening;

aligning a number of electrically conductive pads defined on one surface of an integrated imaging circuit with corresponding ones of said number of electrically conductive leads, each of said number of electrically conductive pads having a solder bump affixed thereto;

embedding said integrated imaging circuit into said formable optically transmissive medium and with said solder bumps in contact with corresponding ones of said number of electrically conductive leads; and

heating said substrate, resiliently compressible circuit member and integrated imaging circuit to simultaneously reflow said solder bumps and cure said formable optically transmissive medium.

22. A method of assembling an optical information processing circuit, the method comprising the steps of:

providing an optically transmissive substrate;

affixing a resiliently compressible circuit member to one side of said substrate, said resiliently compressible circuit member defining an opening therethrough with a number of electrically conductive leads disposed about said opening;

aligning a number of electrically conductive pads defined on one surface of an integrated imaging circuit with corresponding ones of said number of electrically conductive leads, each of said number of electrically conductive pads having a solder bump affixed thereto;

bringing said solder bumps in contact with corresponding ones of said number of electrically conductive leads; and

reflowing said solder bumps to mechanically and electrically attach said number of electrically conductive pads to corresponding ones of said number of electrically conductive lead.

23. The method of claim 22 further including the steps of:

dispensing a formable optically transmissive medium between and in contact with said substrate and said integrated imaging circuit; and

curing said formable optically transmissive medium.