Method for Preparing an Electric Circuit Comprising Multiple Leds

• US 20080203405A1
• Filed: 08/04/2006
• Published: 08/28/2008
• Est. Priority Date: 08/05/2005
• Status: Abandoned Application

• Current Assignee: Lemnis Lighting Patent Holding B.V.
• Original Assignee: Lemnis Lighting Patent Holding B.V.
• Inventors: Rooymans, Johannes Otto
• Application Number:
  US11/997,932
• Publication Number:
  US 20080203405A1
• Time in Patent Office: Days
• US Class Current: 257/91
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/40 Details of LED load circuits

Abstract

The invention relates to a method for preparing an electric circuit comprising a plurality of Light-Emitting Diodes (LEDs). First, a continuous layer of a first semiconductor material is provided. On this a first pattern of a material of a second semiconductor type is applied. Next, a substrate comprising a second pattern of at least one conducting layer (34) is attached to the first pattern. After this, the continuous layer is cut according to a third pattern. Thus the plurality of LEDs is formed.

Claims

1. Method for preparing an electric circuit comprising a plurality of LEDs, said method comprising the steps of:

a) providing a continuous layer of a first semiconductor material;

b) providing a layer of a second semiconductor material in a first pattern, contiguous with the continuous layer;

c) providing a substrate with a layer of a conducting material in a second pattern;

d) attaching the layer of the second semiconductor material in the first pattern to the layer of conducting material in the second pattern; and

e) cutting the continuous layer to form individual LEDs.

2. Method according to claim 1, in which the first semiconductor material is an n-type semiconductor material, and the second semiconductor material is a p-type semiconductor material.

3. Method according to claim 1 or 2, in which the continuous layer is applied on a substrate.

4. Method according to claim 3, in which step e) is performed before step d).

5. Method according to any one of claims 1-4, characterized in that the electric circuit comprises at least one diode-bridge circuit (23).

6. Electric circuit comprising a plurality of LEDs, in which the electric circuit is prepared according to the method according to any one of claims 1-5.

7. Method according to claim 1 for preparing an electric circuit comprising a plurality of LEDs (4,5,6,7), which method comprises the steps of:

providing a first substrate comprising an emitting side and an attachment side, in which the first substrate comprises a first layer (30) of a first semiconductor type and a second layer (31) of a second semiconductor type according to a first pattern, in which the second layer (31) is disposed on the attachment side of the first substrate;

attaching the attachment side of the first substrate to a second substrate (33), the second substrate (33) being insulating and comprising a second pattern of at least one conducting layer (34); and

cutting the first substrate from the emitting side of the first substrate up to the second pattern of the at least one conducting layer (34) according to a third pattern, whereby the plurality of LEDs (4, 5, 6, 7) is formed.

8. Method according to claim 1, in which, before attaching, the attachment side of the first substrate is provided with a fourth pattern of at least one conducting layer (35).

9. Method according to claim 7 or 8, in which the attachment of the first substrate to the second substrate (33) takes place using bumps (40, 41).

10. Method according to claim 9, characterized in that the bumps (40, 41) comprise at least bumps of a first and a second size (40, 41), in which upon attachment the bumps of the first size (40) contact the first layer (30) of the first semiconductor type, and the bumps of the second size (41) contact the second layer (31) of the second semiconductor type.

11. Method according to claim 10, characterized in that the first size is larger than the second size.

12. Method according to any one of claims 7-11, characterized in that at least before cutting, the method further comprises applying a third insulating substrate (38) on the emitting side of the first substrate, the third substrate (38) being transparent for a wavelength that can be generated by at least one of the plurality of LEDs (4, 5, 6, 7).

13. Method according to claim 12, characterized in that the third substrate (38) comprises sapphire.

14. Method according to any one of claims 7-13, in which the second substrate (33) comprises aluminum and is (hard) anodized on at least one side.

15. Method according to any one of the previous claims, characterized in that the first semiconductor type is an n-type conductor, and the second semiconductor type is a p-type conductor.

16. Method according to claim one for preparing an electric circuit comprising a plurality of LEDs (4, 5, 6, 7), in which the method comprises the steps of:

providing a first insulating substrate (50) transparent for a wavelength that can be generated by least one of the plurality of LEDs (4, 5, 6, 7);

forming a layer comprising a first layer (51) of a first semiconductor type and a second layer (52) of a second semiconductor type, on the first insulating substrate (50);

selectively removing the second layer (52) according to a first pattern until a part of the first layer (51) is exposed, and at least by grooves (53) an isolated area (54a, 54b) of the second semiconductor type is formed;

selectively, according to a second pattern, applying at least one conducting layer (55), whereby a first connection with the first layer (51) of the first semiconductor type and a second connection with the isolated area (54a, 54b) of the second semiconductor type is made;

cutting through the at least one conducting layer (55), the second layer (52) of the second semiconductor type and the first layer (51) of the first semiconductor type up to the first insulating substrate (50) according to a third pattern, forming the plurality of LEDs (4, 5, 6, 7); and

attaching the at least one conducting layer (55) on the first insulating substrate (50) to the second insulating substrate (57) comprising a third pattern of at least one conducting layer (59), whereby at least one conducting contact is formed between the at least one conducting layer (55) on the first insulating substrate (50) and the at least one conducting layer (59) on the second insulating substrate (57).

17. Method according to claim 16, characterized in that the first insulating substrate (50) comprises sapphire.

18. Method according to claim 16 or 17, in which the second insulating substrate (57) comprises aluminum and is (hard) anodized on at least one side.

19. Method according to any one of claims 16-18, characterized in that the electric circuit comprises at least one diode-bridge circuit (23).

20. Method according to any one of claims 16-19, characterized in that the first semiconductor type is an n-type conductor, and the second semiconductor type is a p-type conductor.

21. Electric circuit comprising a plurality of LEDs (4, 5, 6, 7), which electric circuit is prepared according to the method according to any one of claims 16-20.