Method of manufacturing light emitting element

Patent metadata

Field	Value
Publication number	US-11489086-B2
Application number	US-202016908354-A
Country	US
Kind code	B2
Filing date	Jun 22, 2020
Priority date	Jul 1, 2019
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

A method of manufacturing light emitting elements includes: providing a wafer including a substrate formed of sapphire and having a first main surface and a second main surface, and a semiconductor layered body disposed on the first main surface of the substrate; irradiating a laser beam into the substrate to form a modified region inside the substrate, the modified region having a crack reaching the first main surface and a crack reaching the second main surface; irradiating CO 2 laser to a region of the substrate overlapping with a region to which the laser beam has been irradiated; and cleaving the wafer along the modified region to obtain the light emitting elements each having a hexagonal shape in a plan view.

First claim

What is claimed is:

1. A method of manufacturing light emitting elements, the method comprising:
providing a wafer, the wafer including
a substrate formed of sapphire and having a first main surface and a second main surface, and
a semiconductor layered body disposed on the first main surface of the substrate;

irradiating a laser beam into the substrate to form a modified region inside the substrate, the modified region having a crack reaching the first main surface and a crack reaching the second main surface;
irradiating CO 2 laser to a region of the substrate overlapping with a region to which the laser beam has been irradiated; and
cleaving the wafer along the modified region to obtain the light emitting elements each having a hexagonal shape in a plan view, wherein
the cleaving of the wafer includes bonding the wafer to an elastic sheet and applying air pressure from a side of the elastic sheet opposite to the wafer, and
the irradiating of the CO 2 laser includes irradiating the CO 2 laser with an output of the CO 2 laser being 3 W or higher and being lower than 30 W.

2. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the laser beam includes irradiating the laser beam from a second main surface side of the substrate.

3. The method of manufacturing light emitting elements according to claim 2 , wherein
the irradiating of the laser beam includes:
scanning the laser beam along a first direction parallel to a first side and a second side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the first side and the second side;
scanning the laser beam in a second direction parallel to a third side and a fourth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the third side and the fourth side; and
scanning the laser beam in a third direction parallel to a fifth side and a sixth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the fifth side and the sixth side.

4. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the laser beam includes irradiating the laser beam from a second main surface side of the substrate.

5. The method of manufacturing light emitting elements according to claim 4 , wherein
the irradiating of the laser beam includes:
scanning the laser beam along a first direction parallel to a first side and a second side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the first side and the second side;
scanning the laser beam in a second direction parallel to a third side and a fourth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the third side and the fourth side; and
scanning the laser beam in a third direction parallel to a fifth side and a sixth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the fifth side and the sixth side.

6. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the laser beam includes:
scanning the laser beam along a first direction parallel to a first side and a second side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the first side and the second side;
scanning the laser beam in a second direction parallel to a third side and a fourth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the third side and the fourth side; and
scanning the laser beam in a third direction parallel to a fifth side and a sixth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the fifth side and the sixth side.

7. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the laser beam includes:
scanning the laser beam along a first direction parallel to a first side and a second side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the first side and the second side;
scanning the laser beam in a second direction parallel to a third side and a fourth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the third side and the fourth side; and
scanning the laser beam in a third direction parallel to a fifth side and a sixth side of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the fifth side and the sixth side.

8. The method of manufacturing light emitting elements according to claim 1 , wherein
the cleaving of the wafer includes stretching the elastic sheet by the applying of the air pressure.

9. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the CO 2 laser includes irradiating the CO 2 laser from a second main surface side of the substrate.

10. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the CO 2 laser includes irradiating the CO 2 laser with the output of the CO 2 laser in a range of 10 W to 20 W.

11. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the CO 2 laser includes irradiating the CO 2 laser with a laser spot diameter of the CO 2 laser in a range of 100 μm to 700 μm.

12. The method of manufacturing light emitting elements according to claim 1 , wherein
the irradiating of the CO 2 laser includes irradiating the CO 2 laser with an interval of the CO 2 laser in a range of 5 μm to 50 μm.

13. A method of manufacturing light emitting elements comprising:
providing a wafer, the wafer including
a substrate formed of sapphire and having a first main surface and a second main surface, and
a semiconductor layered body disposed on the first main surface of the substrate;

irradiating a laser beam into the substrate to form a modified region inside the substrate, the modified region having a crack reaching the first main surface and a crack reaching the second main surface;
irradiating CO 2 laser to a region of the substrate overlapping with a region to which the laser beam has been irradiated; and
cleaving the wafer along the modified region to obtain the light emitting elements each having a hexagonal shape in a plan view, wherein
the cleaving of the wafer includes bonding the wafer to an elastic sheet and applying air pressure from a side of the elastic sheet opposite to the wafer, wherein
the irradiating of the laser beam includes
scanning the laser beam in a zig-zag manner along sides of the hexagonal shape to irradiate the laser beam to regions corresponding to the sides of the hexagonal shape.

14. The method of manufacturing light emitting elements according to claim 13 , wherein
the irradiating of the laser beam further includes
scanning the laser beam along a direction parallel to a pair of opposing sides of the hexagonal shape, which are parallel to each other, to irradiate the laser beam to regions corresponding to the opposing sides.

15. A method of manufacturing light emitting elements, the method comprising:
providing a wafer, the wafer including
a subst

Assignees

• Nichia Corp

Inventors

• Inoue Naoto
• Yamamoto Minoru
• Okumura Satoshi
• Okamoto Hiroki
• Tamemoto Hiroaki

Classifications

• B23K26/0736

  into an oval shape, e.g. elliptic shape · CPC title

• B23K26/0622

  by shaping pulses · CPC title

• B23K2103/50

  Inorganic materials other than metals or composite materials · CPC title

• B23K26/53

  for modifying or reforming the material inside the workpiece, e.g. for producing break initiation cracks · CPC title

• B23K26/082

  Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head · CPC title