FLEXIBLE LED DEVICE WITH WIRE BOND FREE DIE

• US 20130213697A1
• Filed: 10/27/2011
• Published: 08/22/2013
• Est. Priority Date: 11/03/2010
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Palaniswamy, Ravi, Ouderkirk, Andrew J., Mooney, Justine A., Jesudoss, Arokiaraj, Narag, Alejandro Aldrin Il Agcaoili, Foo, Siang Sin, Tan, Fong Liang
• Granted Patent: US 9,179,543 B2
• Time in Patent Office: Days
• US Class Current: 174/254
• CPC Class Codes: H01L 24/17 of a plurality of bump connectors
• 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 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/01327 Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/07802 not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/12032 Schottky diode
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2924/1461 MEMS
• CPC Class Codes: H01L 2924/15787 Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/351 Thermal stress
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/60 Reflective elements
• 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: H01L 33/64 Heat extraction or cooling elements
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/0277 Bendability or stretchability details H05K1/038, H05K3/4691 take precedence
• CPC Class Codes: H05K 1/183 : Components mounted in and supported by recessed areas of the printed circuit board
• CPC Class Codes: H05K 1/189 : characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2201/2054 : Light-reflecting surface, e.g. conductors, substrates, coatings, dielectrics

Abstract

An article includes a flexible polymeric dielectric layer having first and second major surfaces. The first major surface has a conductive layer thereon and at least one cavity therein. The at least one cavity contains a conductive material including electrically separated first and second portions supporting and electrically connecting a light emitting semiconductor device to the conductive layer on the first major surface.

Claims

1. An article comprising:

a flexible polymeric dielectric layer having first and second major surfaces, the first major surface having a conductive layer thereon and having at least one cavity therein, the at least one cavity containing a conductive material including electrically separated first and second portions configured to support and electrically connect a light emitting semiconductor device to the conductive layer on the first major surface.

2. The article of claim 1, wherein the conductive material in the cavity is electrically insulated from the second major surface.

3. The article of claim 1, wherein the second major surface has a conductive layer thereon.

4. The article of claim 3, wherein the conductive material in the cavity is electrically connected to the conductive layer on the second major surface.

5. The article of claim 1, wherein the at least one cavity is at least 25% filled with conductive material.

6. The article of claim 1, wherein the top surface of the at least one cavity is reflective.

7. The article of claim 1, wherein the top surface of the at least one cavity comprises a reflective material applied over at least a portion of the conductive material in the at least one cavity.

8. The article of claim 1, wherein the distance between the bottom of the at least one cavity and the second major surface is about 5% to about 75% of the thickness of the dielectric layer.

9. The article of claim 1, wherein the floor of the cavity comprises a dielectric coating disposed at the bottom of the at least one cavity to electrically insulate the at least one cavity from the second major surface of the dielectric layer.

10. The article of claim 1, wherein the at least one cavity has walls that slope from the first major surface to the bottom of the at least one cavity at an angle of about 5°

to about 60°

from the major plane of the dielectric layer.

12. The article of claim 1 or claim 11, wherein the first and second portions of the conductive material are electrically separated by a gap or a ridge.

13. The article of claim 1 or claim 11 further comprising a light emitting semiconductor device supported and electrically connected to the conductive layer on the first major surface by the first and second portions.

14. The article of claim 13, wherein the light emitting semiconductor device is a flip chip die or a lateral die.

11. An article comprising:

a flexible polymeric dielectric layer having first and second major surfaces, the first and second major surfaces each having a conductive layer thereon, the dielectric layer having at least one via extending from the first major surface to the second major surface, the at least one via containing a conductive material electrically connected to the conductive layer on the second major surface and including electrically separated first and second portions configured to support and electrically connect a light emitting semiconductor device to the conductive layer on the first major surface.

15. An article comprising:

a flexible polymeric dielectric layer having a first major surface with a first conductive layer thereon and having a second major surface with a second conductive layer thereon, the dielectric layer having at least one cavity, or via, extending from the first major surface toward, or to, the second major surface;

the first conductive layer extending into the at least one cavity, or via; and

the at least one cavity, or via, containing a conductive feature and two conductive pads, the conductive pads electrically insulated from each other and from the conductive feature.