IP Library Granted Patent US 7,795,051
Granted Patent B2
US 7,795,051 · App. 11/626,280 · Granted Sep 14, 2010

Accurate alignment of an LED assembly

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,795,051
App. No.
11/626,280
Granted
Sep 14, 2010
Kind
B2
Abstract

An LED assembly includes a heat sink and a submount. The heat sink has a top mating surface that is solder wettable, and the submount has a bottom mating surface that is solder wettable. The top and the bottom mating surfaces have substantially the same shape and area. The submount is soldered atop the heat sink. During solder reflow, the molten solder causes the submount to align with the top mating surface of the heat sink. The LED assembly may further include a substrate having a top mating surface, and the heat sink may further include a bottom mating surface. The top and bottom mating surfaces have substantially the same shape and area. The heat sink is soldered atop the substrate. During solder reflow, the molten solder causes the heat sink to align with the top mating surface of the substrate.

Claims (35)

1. A method for assembling LED components, comprising;

mounting an LED die on a submount;

applying a first solder between a bottom mating surface of the submount and a raised top mating surface of a heat sink, wherein at least the bottom mating surface and the raised top mating surface are solder wettable and have substantially the same shape and area;

reflowing the first solder, whereby the submount and the heat sink are aligned and bonded together during reflowing, wherein the first solder aligns perimeters of the bottom mating surface and the raised top mating surface with an accuracy of at least 20 microns;

applying a second solder between a raised bottom mating surface of the heat sink and a top mating surface of a substrate wherein at least the raised bottom mating surface and the top mating surface are solder wettable and have substantially the same shape and area; and

reflowing the second solder, whereby the heat sink and the substrate are aligned and bonded together during reflowing.

2. The method of claim 1 , wherein said applying a solder comprises: applying the first solder to the raised top mating surface of the heat sink, and placing the bottom mating surface of the submount on the solder atop the raised top mating surface of the heat sink.

3. The method of claim 1 , wherein said applying a second solder comprises:

applying the second solder to the second top mating surface of the substrate; and

placing the second bottom mating surface of the heat sink on the second solder atop the second top mating surface of the substrate.

4. A method for assembling LED components, comprising:

mounting an LED die on a submount;

applying a first solder between a first bottom mating surface of the submount and a first top mating surface of a heat sink, wherein the first bottom mating surface and the first top mating surface are solder wettable and have substantially the same shape and area;

reflowing the first solder, whereby the submount and the heat sink are aligned and bonded together during reflowing, wherein the first solder aligns perimeters of the bottom mating surface and the raised top mating surface with an accuracy of at least 20 microns;

applying a second solder between a raised bottom mating surface of the heat sink and a top mating surface of a substrate, wherein the bottom mating surface and the top mating surface are solder wettable and have substantially the same shape and area; and

reflowing the second solder, whereby the heat sink and the substrate are aligned and bonded together during reflowing, wherein said reflowing the first solder occurs at a higher temperature than said reflowing the second solder.

5. The method of claim 1 , wherein said mounting an LED die on a submount comprises:

applying a third solder between the LED die and the submount; and

reflowing the third solder, whereby the LED die and the submount are bonded together during reflowing.

6. A method for assembling LED components, comprising:

applying a first solder between an LED die and a submount;

reflowing the first solder, whereby the LED die and the submount are bonded together during reflowing;

applying a second solder between a bottom mating surface of the submount and a raised top mating surface of a heat sink, wherein the bottom mating surface and the raised top mating surface are solder wettable and have substantially the same shape and area;

reflowing the second solder, whereby the submount and the heat sink are aligned and bonded together during reflowing, wherein said reflowing the first solder occurs at a higher temperature than and said reflowing the second solder and the first solder aligns perimeters of the bottom mating surface and the raised top mating surface with an accuracy of at least 20 microns;

applying a third solder between a raised bottom mating surface of the heat sink and a top mating surface of a substrate wherein the raised bottom mating surface and the top mating surface are solder wettable and have substantially the same shape and area; and

reflowing the third solder, whereby the heat sink and the substrate are aligned and bonded together during reflowing.

7. The method of claim 1 , wherein the bottom mating surface and the raised top mating surface have a hexagon shape.

8. The method of claim 1 , wherein the second bottom mating surface and the second top mating surface have a hexagon shape.

9. The method of claim 1 , wherein the heat sink is a thermally conducting slug.

10. A method for assembling LED components, comprising:

applying a first solder of a first liquidous temperature between an LED die and a submount;

reflowing the first solder at a first temperature, whereby the LED die and the submount are bonded together during reflowing; applying a second solder of a second liquidous temperature between a bottom mating surface of the submount and a raised top mating surface of a heat sink, wherein the bottom mating surface and the raised top mating surface are solder wettable and have substantially the same shape and area;

reflowing the second solder at a second temperature, whereby the submount and the heat sink are aligned and bonded together during reflowing, wherein the first solder aligns perimeters of the bottom mating surface and the raised top mating surface with an accuracy of at least 20 microns;

applying a third solder of a third liquidous temperature between a raised bottom mating surface of the heat sink and a top mating surface of a substrate, wherein the raised bottom mating surface and the top mating surface are solder wettable and have substantially the same shape and area; and

reflowing the third solder at a third temperature, whereby the heat sink and the substrate are aligned and bonded together during reflowing, wherein said reflowing the second solder occurs at a higher temperature than said reflow the third solder.

Assignments (7)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 10, 2025
From: LUMILEDS LLC
To: LUMILEDS SINGAPORE PTE. LTD.
Reel/Frame 071888/0086 →
RELEASE OF SECURITY INTEREST Recorded Jan 29, 2025
From: SOUND POINT AGENCY LLC
To: LUMILEDS LLC; LUMILEDS HOLDING B.V.
Reel/Frame 070046/0001 →
SECURITY INTEREST Recorded Jan 5, 2023
From: LUMILEDS LLC; LUMILEDS HOLDING B.V.
To: SOUND POINT AGENCY LLC
Reel/Frame 062299/0338 →
CHANGE OF NAME Recorded Jan 23, 2018
From: PHILIPS LUMILEDS LIGHTING COMPANY, LLC
To: LUMILEDS LLC
Reel/Frame 045759/0612 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 18, 2018
From: LUMILEDS LIGHTING U.S., LLC
To: PHILIPS LUMILEDS LIGHTING COMPANY, LLC
Reel/Frame 044652/0135 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 20, 2017
From: ELPEDES, CRESENTE S.; AZIZ, ZAINUL FITERI BIN; MARTIN, PAUL S.
To: LUMILEDS LIGHTING US; LLC
Reel/Frame 044442/0509 →
SECURITY INTEREST Recorded Jul 7, 2017
From: LUMILEDS LLC
To: DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT
Reel/Frame 043108/0001 →