Plastic packaging of LED arrays

• US 6,733,711 B2
• Filed: 03/14/2003
• Issued: 05/11/2004
• Est. Priority Date: 09/01/2000
• Status: Expired due to Term

• Current Assignee: Current Lighting Solutions, LLC (f/k/a GE Lighting Solutions, LLC) (American Industrial Partners)
• Original Assignee: General Electric Company
• Inventors: Durocher, Kevin Matthew, Saia, Richard Joseph, Balch, Ernest Wayne, Krishnamurthy, Vikram B., Cole, Herbert Stanley, Kolc, Ronald Frank
• Primary Examiner(s): ORTIZ, ANGELA Y
• Application Number:
  US10/387,835
• Publication Number:
  US 20030153108A1
• Time in Patent Office: 424 Days
• Field of Search: 438/26, 438/28, 438/106, 438/113, 438/119, 438/121, 438/124, 438/125, 438/129, 264/259, 264/261, 264/271.1, 264/272.11, 264/272.15, 264/275, 264/277, 257/678, 298/31, 298/46, 298/54, 298/55, 298/56
• US Class Current: 264/272.14
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/85 using a wire connector
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 23/13 characterised by the shape
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 23/49833 the chip support structure consisting of a plurality of insulating substrates
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01039 : Yttrium [Y]
• CPC Class Codes: H01L 2924/01047 : Silver [Ag]
• CPC Class Codes: H01L 2924/01058 : Cerium [Ce]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/07811 : Extrinsic, i.e. with electrical conductive fillers
• CPC Class Codes: H01L 2924/10329 : Gallium arsenide [GaAs]
• CPC Class Codes: H01L 2924/12041 : LED
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/1433 : Application-specific integrated circuit [ASIC]
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15157 : Top view
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19042 : being an inductor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/207 : Diameter ranges
• CPC Class Codes: H01L 33/46 : Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: Y10S 362/80 : Light emitting diode
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49169 : Assembling electrical component directly to terminal or elongated conductor
• CPC Class Codes: Y10T 29/49171 : with encapsulating

Abstract

There is provided a flexible circuit module, including at least one rigid carrier, at least one solid state device mounted over a first side of the at least one rigid carrier, a flexible base supporting a second side of the at least one rigid carrier, a conductive interconnect pattern on the flexible base, and a plurality of feed through electrodes extending from the first side to the second side of the at least one rigid carrier and electrically connecting the conductive interconnect pattern with the at least one of a plurality of the solid state devices. The solid state devices may be LED chips to form an LED array module.

Claims

1. A method of forming a packaged solid state device, comprising:

placing at least one conductive element into a mold cavity;

filling the mold cavity with a fluid insulating material;

solidifying the fluid insulating material to form an insulating carrier, wherein at least two surfaces of the at least one conductive element are exposed after solidification; and

placing at least one solid state device on the insulating carrier in contact with one surface of the at least one conductive element.

2. The method of claim 1, wherein the at least one conductive element comprises a metal heat sink.

3. The method of claim 1, wherein the at least one conductive element comprises at least two metal electrodes.

4. The method of claim 3, wherein the at least one solid state device comprises at least one light emitting diode chip in electrical contact with the at least two metal electrodes.

5. The method of claim 4, wherein:

the step of filling comprises filling the mold with a fluid plastic or epoxy material;

the step of solidifying comprises heating or cooling the fluid plastic material to form a rigid plastic insulating carrier containing at least one cavity; and

the step of placing at least one solid state device comprises placing at least one light emitting diode chip into the at least one cavity in contact with the exposed top surfaces of the two electrodes.

6. The method claim 4, wherein

the step of filling comprises filling the mold with a powder plastic material and fluidizing the powder plastic material;

the step of solidifying comprises heating the fluidized material under pressure to form a rigid plastic insulating carrier containing at least one cavity; and

the step of placing at least one solid state device comprises placing at least one light emitting diode chip into the at least one cavity in contact with the exposed top surfaces of the two electrodes.

7. The method of claim 4, further comprising:

adhering a first side of the insulating carrier to a first side of a flexible module base; and

forming a conductive interconnect pattern over a second side of the flexible module base extending through the flexible module base toward the insulating carrier to form an electrical connection with the at least one light emitting diode chip.

8. A method of forming a packaged solid state device, comprising:

placing a plurality of feed through electrodes into a mold cavity;

filling the mold cavity with a fluid insulating material;

solidifying the fluid insulating material to form an insulating rigid carrier, such that first surfaces of the feed through electrodes are exposed in a first surface of the rigid carrier and second surfaces of the feed through electrodes are exposed in a second surface of the rigid carrier after solidification;

adhering the first side of the rigid carrier over a first side of a flexible module base, wherein the flexible module base comprises an insulating material;

forming a conductive interconnect pattern having a first portion over a second side of the flexible module base and a plurality of second portions extending through the flexible module base and contacting the exposed first surfaces of the feed through electrodes; and

forming at least one light emitting diode on the second side of the rigid carrier and in electrical contact with the exposed second surfaces of the feed through electrodes.

9. The method of claim 8, wherein the step of adhering comprises forming an adhesive layer between the first side of the rigid carrier and the first side of the flexible module base prior to the step of forming the conductive interconnect but after the step of forming the plurality of feed through electrodes.

10. The method of claim 9, wherein the step of forming the conductive interconnect pattern comprises:

forming vias in the flexible module base extending through the adhesive layer, such that the vias expose the plurality of the feed through electrodes;

depositing at least one metal layer over the second side of the flexible module base and in the vias; and

patterning the metal layer to form the conductive interconnect.

11. The method of claim 8, wherein:

the step of filling comprises filling the mold with a fluid plastic or epoxy material;

the step of solidifying comprises heating or cooling the fluid plastic material to form a plastic insulating rigid carrier containing at least one cavity; and

the step of forming at least one light emitting diode comprises placing at least one light emitting diode chip into the at least one cavity.

12. The method claim 8, wherein:

the step of filling comprises filling the mold with a powder plastic material and fluidizing the powder plastic material;

the step of solidifying comprises heating the fluidized material under pressure to form a plastic insulating rigid carrier containing at least one cavity; and

the step of forming at least one light emitting diode comprises placing at least one light emitting diode chip into the at least one cavity.

13. The method of claim 8, wherein the step of forming at least one light emitting diode comprises placing a plurality of light emitting diode chips with chip pads toward the second side of the rigid carrier such that the chip pads contact the exposed second surfaces of the feed through electrodes.

14. The method of claim 8, the step of forming at least one light emitting diode comprises:

placing a plurality of light emitting diode chips with chip pads away from the second side of the rigid carrier; and

wire bonding a plurality of lead wires between the chip pads and the exposed second surfaces of the feed through electrodes.

15. A method of forming a packaged solid state device, comprising:

placing a plurality of feed through electrodes into a mold cavity;

filling the mold cavity with a fluid insulating material;

solidifying the fluid insulating material to form an insulating rigid carrier, such that first surfaces of the feed through electrodes are exposed in a first surface of the rigid carrier and second surfaces of the feed through electrodes are exposed in a second surface of the rigid carrier after solidification;

forming a conductive interconnect pattern having a first portion over a second side of a flexible module base and a plurality of second portions extending through the flexible module base, wherein the flexible module base comprises an insulating material;

adhering the first side of the rigid carrier over a first side of a flexible module base using an anisotropic adhesive layer; and

forming at least one light emitting diode on the second side of the rigid carrier and in electrical contact with the exposed second surfaces of the feed through electrodes;

wherein;

the anisotropic adhesive layer is located between the first side of the rigid carrier and the first side of the flexible module base and in electrical contact with the exposed first sides of the feed through electrodes; and

the anisotropic adhesive layer is electrically conductive substantially along a first axis between the rigid carrier and the flexible module base, but is electrically insulating substantially along a direction perpendicular to the first axis.

16. The method of claim 15, wherein the step of forming the plurality of feed through electrodes and the step of forming the conductive interconnect pattern occur prior to the step of adhering.

17. The method of claim 15, wherein:

the step of filling comprises filling the mold with a fluid plastic or epoxy material;

the step of solidifying comprises heating or cooling the fluid plastic material to form a plastic insulating rigid carrier containing at least one cavity; and

the step of forming at least one light emitting diode comprises placing at least one light emitting diode chip into the at least one cavity.

18. The method claim 15, wherein:

the step of filling comprises filling the mold with a powder plastic material and fluidizing the powder plastic material;

the step of solidifying comprises heating the fluidized material under pressure to form a plastic insulating rigid carrier containing at least one cavity; and

the step of forming at least one light emitting diode comprises placing at least one light emitting diode chip into the at least one cavity.

19. The method of claim 15, wherein the step of forming at least one light emitting diode comprises placing a plurality of light emitting diode chips with chip pads toward the second side of the rigid carrier such that the chip pads contact the exposed second surfaces of the feed through electrodes.

20. The method of claim 15, wherein the step of forming at least one light emitting diode comprises:

placing a plurality of light emitting diode chips with chip pads away from the second side of the rigid carrier; and

wire bonding a plurality of lead wires between the chip pads and the exposed second surfaces of the feed through electrodes.