LIGHT EMITTING DIODE AND MANUFACTURING METHOD THEREOF

• US 20160247964A1
• Filed: 02/17/2016
• Published: 08/25/2016
• Est. Priority Date: 02/17/2015
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Genesis Photonics Inc.
• Inventors: Ting, Shao-Ying, Huang, Jing-En
• Granted Patent: US 9,728,672 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 21/6836 Wafer tapes, e.g. grinding or dicing support tapes adhesive tapes in general C09J7/20
• CPC Class Codes: H01L 2221/68327 used during dicing or grinding
• CPC Class Codes: H01L 2221/68336 involving stretching of the auxiliary support post dicing
• CPC Class Codes: H01L 2221/6834 used to protect an active side of a device or wafer
• CPC Class Codes: H01L 2221/68381 Details of chemical or physical process used for separating the auxiliary support from a device or wafer
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• 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: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

A light-emitting diode (LED) and a method for manufacturing the same are provided. The method includes following steps. An LED wafer is fixed on a crafting table and is processed such that a substrate of the LED wafer has a thickness smaller than or equal to 100 μm. A fixing piece is pasted on the LED wafer surface. The LED wafer is detached from the crafting table. The LED wafer together with the fixing piece are cut and broken, such that the LED wafer forms a plurality of LEDs. The fixing piece is removed. Before the LED wafer is detached from the crafting table, the fixing piece is pasted on the LED wafer to provide a supporting force to the LED wafer to maintain the flatness of the wafer and avoid the wafer being warped or the substrate being broken or damaged, such that product quality and reliability can be improved.

Claims

1. A method for manufacturing a light-emitting diode (LED), comprising:

providing an LED wafer comprising a substrate;

pasting a fixing piece on a surface of the substrate;

cutting the LED wafer together with the fixing piece to form a plurality of LEDs; and

removing the fixing piece.

2. The method according to claim 1, wherein before the step of pasting the fixing piece on the surface of the substrate, the method further comprises a grinding step, such that the substrate has a thickness smaller than or equal to 100 μ

m.

3. The method according to claim 2, wherein before the grinding step, the method further comprises a waxing step for adhering the LED wafer on a crafting table.

4. The method according to claim 3, further comprising a dewaxing step for detaching the LED wafer from the crafting table.

5. The method according to claim 1, wherein the fixing piece is a sheet having a viscose and the step of removing the fixing piece is implemented by firstly projecting a UV light on the fixing piece to decompose the viscose and then removing the fixing piece from the LEDs.

6. The method according to claim 1, wherein before the step of cutting, the method further comprises a step of fixing the LED wafer on an elastic membrane. The method according to claim 6, wherein after the step of removing the fixing piece, the method further comprises a step of expanding the elastic membrane, such that the LEDs are separated from each other as the elastic membrane expands.

8. A manufacturing method of light-emitting diode (LED) characterized in that the method comprises:

providing an LED wafer comprising a substrate;

fixing the LED wafer on a crafting table and further processing the LED wafer, such that the substrate has a thickness smaller than or equal to 100 μ

m;

pasting a fixing piece on a surface of the LED wafer and removing the LED wafer from the crafting table;

cutting and breaking the LED wafer together with the fixing piece, such that the LED wafer forms a plurality of LEDs; and

removing the fixing piece.

9. The method according to claim 8, wherein the step of fixing the LED wafer on the crafting table comprises:

coating a liquid wax on a surface of the light-emitting unit surface; and

adhering the LED wafer on the crafting table.

10. The method according to claim 9, wherein the step of removing the LED wafer from the crafting table comprises:

removing the wax between the LED wafer and the crafting table.

11. The method according to claim 8 characterized in that the fixing piece is a sheet having viscose and the step of removing the fixing piece is implemented by firstly projecting a UV light on the fixing piece to decompose the viscose and then removing the fixing piece from the LEDs.

12. The method according to claim 8 characterized in that before the cutting and breaking step, the method further comprises a step of fixing the LED wafer on an elastic membrane.

13. The method according to claim 12 characterized in that after the step of removing the fixing piece, the method further comprises a step of expanding the elastic membrane, such that the LEDs are separated from each other as the elastic membrane expands.

14. A light-emitting diode (LED), comprising:

a substrate; and

a light-emitting unit comprising an n-type semiconductor layer, a p-type semiconductor layer, and a light-emitting layer interposed between the n-type semiconductor layer and the p-type semiconductor layer;

wherein, the substrate has a thickness 2-20 times larger than a thickness of the light-emitting unit.

15. The LED according to claim 14, wherein the substrate has the thickness 5-10 times larger than the thickness of the light-emitting unit.

16. The LED according to claim 14, wherein the substrate has the thickness between 20-100 μ

m.

17. The LED according to claim 14, wherein the LED has a beam-divergence angle between 115°

-140°

.