Light-emitting device and manufacturing method thereof
A manufacturing method of a light-emitting device includes steps of: providing a substrate with a top surface, wherein the top surface comprises a plurality of concavo-convex structures; forming a semiconductor stack on the top surface; forming a trench in the semiconductor stack to define a plurality of second semiconductor stacks and expose a first upper surface; forming a scribing region which extends from the first upper surface into the semiconductor stack and exposes a side surface of the semiconductor stack to define a plurality of first semiconductor stacks; removing a portion of the plurality of first semiconductor stacks and a portion of the concavo-convex structures trough the region to form a first side wall of each of the first semiconductor stack; and dividing the substrate along the region; wherein the first side wall and the top surface form an acute angle α between thereof, 30°≤α≤80°.
1. A manufacturing method of a light-emitting device, comprising:
providing a substrate with a top surface, wherein the top surface comprises a plurality of concavo-convex structures;
forming a semiconductor stack on the top surface;
forming a trench in the semiconductor stack to define a plurality of second semiconductor stacks and expose a first upper surface;
forming a region which extends from the first upper surface into the semiconductor stack and exposes a side surface of the semiconductor stack to define a plurality of first semiconductor stacks;
removing a portion of the plurality of first semiconductor stacks and a portion of the concavo-convex structures trough the region to form a first side wall of each of the first semiconductor stack; and
dividing the substrate along the region;
wherein the first side wall and the top surface form an acute angle α between thereof, 30°≤α≤80°.
2. The manufacturing method according to claim 1 , wherein the region is a scribing region.
3. The manufacturing method according to claim 2 , wherein forming the scribing region comprises laser dicing.
4. The manufacturing method according to claim 1 , further comprising forming a protective layer covering the plurality of second semiconductor stacks and the first upper surface.
5. The manufacturing method according to claim 4 , wherein the protective layer comprises SiO x , SiN x or a combination thereof.
6. The manufacturing method according to claim 1 , wherein the method of forming the trench comprises dry etching.
7. The manufacturing method according to claim 1 , wherein removing the portion of the plurality of first semiconductor stacks and the portion of the concavo-convex structures comprises wet etching.
8. The manufacturing method according to claim 1 , wherein the region exposes the concavo-convex structures.
9. The manufacturing method according to claim 1 , wherein dividing the substrate comprises providing a laser beam focusing in the substrate to form a damage region in the substrate.
10. The manufacturing method according to claim 1 , wherein the second semiconductor stack has a second side wall connecting the first upper surface, and an obtuse angle β is formed between the second side wall and the first upper surface, wherein 100°≤β≤170°.
11. The manufacturing method according to claim 1 , further comprising forming a buffer layer on the substrate by physical vapor deposition process before forming the semiconductor stack on the substrate.
12. The manufacturing method according to claim 11 , wherein the buffer layer comprises AlN.
13. The manufacturing method according to claim 1 , further comprises forming a first electrode on the first semiconductor stack and a second electrode on the second semiconductor stack.
14. The manufacturing method according to claim 7 , wherein the portion of the concavo-convex structures after being etched has smaller size than the concavo-convex structures under the first semiconductor stack.
15. The manufacturing method according to claim 3 , wherein the scribing region further extends into the substrate.
16. A manufacturing method of a light-emitting device, comprising:
providing a substrate with a top surface, wherein the top surface comprises a plurality of concavo-convex structures;
forming a semiconductor stack on the top surface;
forming a trench in the semiconductor stack to define a plurality of second semiconductor stacks and expose a first upper surface;
forming a scribing region by a first laser dicing from the first upper surface to define a plurality of first semiconductor stacks;
etching a portion of the plurality of first semiconductor stacks trough the scribing region to form a first side wall of each of the first semiconductor stack; and
dividing the substrate by a second laser dicing along the scribing region,
wherein a second laser beam of the second laser dicing focuses in the substrate; and
wherein the first side wall and the top surface form an acute angle α.
17. The manufacturing method according to claim 16 , wherein the scribing region further extends into the substrate to expose a side surface of the substrate.
18. The manufacturing method according to claim 17 , further comprising etching the side surface of the substrate.
19. The manufacturing method according to claim 16 , wherein the second laser beam forms a damage region in the substrate.
20. The manufacturing method according to claim 16 , wherein 30°≤α≤80°.