Surface mounted infrared image detector systems and associated methods

• US 20080048120A1
• Filed: 08/28/2006
• Published: 02/28/2008
• Est. Priority Date: 08/28/2006
• Status: Active Grant

• Current Assignee: L3 Technologies, Inc. (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Inventors: Gooch, Roland W.
• Granted Patent: US 7,514,684 B2
• Time in Patent Office: Days
• US Class Current: 250/338.4
• CPC Class Codes: G01J 5/10 using electric radiation detectors
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 27/14649 Infrared imagers
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80
• CPC Class Codes: H01L 31/024 Arrangements for cooling, heating, ventilating or temperature compensation for photovoltaic devices H01L31/052
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

An infrared image detector system mounted on a printed circuit board (PCB) is disclosed for use with an infrared imaging system such as an infrared camera. A semiconductor die having an infrared detector array and connection points on a first surface is mounted to a PCB and electrically coupled to electrical connection points on a PCB. In addition, a heat sink can be coupled to an opposing second surface of the semiconductor die. Still further, the PCB can have a window within which the infrared image detector array can be positioned so that the infrared image detector system can be mounted to one side of the PCB while infrared radiation incident on the second side of the PCB will reach the infrared image detector array through the window.

Claims

1. An image detector assembly for infrared imaging systems, comprising:

a printed circuit board (PCB) having a plurality of electrical connection points; and

an infrared image detector system mounted to the PCB, the infrared image detector system comprising a semiconductor die having a first and second opposing surfaces, an infrared image detector array formed on the first surface of the semiconductor die, and a plurality of electrical connection points coupled to the electrical connection points of the PCB.

2. The image detector assembly of claim 1, further comprising a heat sink coupled to the opposing second surface of the semiconductor die.

3. The image detector assembly of claim 2, wherein the PCB comprises a first and second surfaces and a window, the infrared image detector system being mounted on the first surface of the PCB such that infrared image detector array is located within the window so that infrared energy directed towards the second surface of the PCB will reach the image detector array.

4. The image detector assembly of claim 3, wherein the infrared image detector system further comprises:

a semiconductor lid coupled to the first surface of the semiconductor die and configured to cover the infrared image detector array, the semiconductor lid configured to be transparent to infrared radiation and configured to form a vacuum sealed region above the infrared image detector array;

a plurality of connection points on the first surface of the semiconductor die electrically coupled to the plurality of connection points on the PCB.

5. The image detector assembly of claim 3, further comprising a material transparent to infrared radiation configured to cover the infrared image detector array.

6. The image detector assembly of claim 3, wherein the electrical connection points on the first surface of the semiconductor die comprise bond pads and are surface mounted to the PCB electrical connection points.

7. The image detector assembly of claim 6, further comprising a spacer coupled between the heat sink and the PCB.

8. The assembly of claim 3, further comprising two or more spacers coupled between the heat sink and the PCB to mount the infrared image detector system to the first surface of the PCB.

9. The image detector assembly of claim 8, wherein the electrical connection points on the first surface of the semiconductor die are coupled to the electrical connection points on the PCB utilizing a lead frame, flex leads, or a combination thereof.

10. The image detector assembly of claim 3, further comprising a die clamp coupled to the PCB and positioned to hold the infrared image detector system within the window, the infrared image detector system being mounted to the die clamp.

11. The assembly of claim 10, wherein the electrical connection points on the first surface of the semiconductor die are coupled to the electrical connection points on the PCB utilizing a lead frame, flex leads, or a combination thereof.

12. The image detector assembly of claim 1, wherein the second surface of the semiconductor die is coupled to the PCB without an intervening heat sink.

13. The image detector assembly of claim 12, wherein the PCB is configured to provide a heat sink for the semiconductor die.

14. The image detector assembly of claim 12, wherein the electrical connection points on the first surface of the semiconductor die are coupled to the electrical connection points on the PCB utilizing a lead frame, flex leads, bond wires or a combination thereof.

15. An infrared imaging system, comprising:

an image detector assembly, comprising;

a printed circuit board (PCB) having a plurality of electrical connection points; and

an infrared image detector system mounted to the PCB, the infrared image detector system comprising a semiconductor die having a first and second opposing surfaces, an infrared image detector array formed on the first surface of the semiconductor die, and a plurality of electrical connection points coupled to the electrical connection points of the PCB;

an infrared lens assembly configured to receive infrared radiation and to focus it on the infrared image detector array;

image processing circuitry coupled to receive image information from the image detector assembly; and

display circuitry coupled to the image processing circuitry and configured to provide image information to a display device.

16. The infrared imaging system of claim 15, further comprising a heat sink coupled to the opposing second surface of the semiconductor die.

17. The infrared imaging system of claim 16, wherein the PCB comprises a first and second surfaces and a window, the infrared image detector system being mounted on the first surface of the PCB such that infrared image detector array is located within the window so that infrared energy directed towards the second surface of the PCB will reach the image detector array.

18. The infrared imaging system of claim 17, wherein the infrared image detector system further comprises:

a semiconductor lid coupled to the first surface of the semiconductor die and configured to cover the infrared image detector array, the semiconductor lid configured to be transparent to infrared radiation and configured to form a vacuum sealed region above the infrared image detector array;

a plurality of connection points on the first surface of the semiconductor die electrically coupled to the plurality of connection points on the PCB.

19. The infrared imaging system of claim 17, wherein the electrical connection points on the first surface of the semiconductor die comprise bond pads and are surface mounted to the PCB electrical connection points.

20. The infrared imaging system claim 17, further comprising two or more spacers coupled between the heat sink and the PCB to mount the infrared image detector system to the first surface of the PCB.

21. A method for assembling an infrared imaging system, comprising:

mounting an infrared image detector system to a printed circuit board (PCB), the infrared image detector system comprising a semiconductor die having a first and second opposing surfaces, an infrared image detector array formed on the first surface of the semiconductor die, and a plurality of electrical connection points;

coupling the plurality of electrical connection points on the first surface of the semiconductor die to a plurality of electrical connection points on the PCB; and

coupling an infrared lens system to the PCB so that infrared energy passing through the infrared lens system on the infrared image detector array.

22. The method of claim 21, wherein a heat sink is coupled to the opposing second surface of the semiconductor die.

23. The method of claim 22, wherein the PCB comprises a first and second surfaces and a window and wherein the infrared image detector system is mounted on the first surface of the PCB such that infrared image detector array is located within the window so that infrared energy directed towards the second surface of the PCB will reach the image detector array.

24. The method of claim 23, wherein the mounting step comprises surface mounting a the electrical connection points on the first surface of the semiconductor die to the PCB electrical connection points.

25. The method of claim 23, wherein the mounting step comprises utilizing one or more spacers coupled between the heat sink and the PCB to mount the infrared image detector system to the first surface of the PCB.

26. The method of claim 23, wherein the mounting step comprises utilizing a die clamp coupled to the PCB to hold the infrared image detector system within the window.

27. The method of claim 21, wherein the mounting step comprises mounting the second surface of the semiconductor die to the PCB without an intervening heat sink.