Light emitting diode and fabrication method thereof
View Patent ↗A light emitting diode (LED). The LED comprises a LED chip comprising an n-type semiconductor layer, a active layer and a p-type semiconductor layer. An n-type ohmic contact electrode and a p-type ohmic contact electrode electrically contact the n-type semiconductor layer and the p-type semiconductor layer respectively. An AlGaInN thick film is on the LED chip, and the AlGaInN thick film has an oblique side and a textured top surface.
1. A light emitting diode (LED), comprising:
a LED chip comprising a n-type semiconductor layer, an active layer and a p-type semiconductor layer;
an n-type ohmic contact electrode electrically contacting the n-type semiconductor layer;
a p-type ohmic contact electrode electrically contacting the p-type semiconductor layer; and
an AlGaInN thick film on the LED chip, and the AlGaInN thick film has an oblique side and a textured top surface.
2. The light emitting diode (LED) as claimed in claim 1 , wherein the AlGaInN thick film is Al X Ga (1-X-Y) In Y N (0≦X, Y<1 and 0≦X+Y<1) thick film.
3. The light emitting diode (LED) as claimed in claim 1 , wherein the AlGaInN thick film is thicker than 20 μm.
4. The light emitting diode (LED) as claimed in claim 1 , wherein the AlGaInN thick film thickness is about 20˜100 μm.
5. The light emitting diode (LED) as claimed in claim 1 , wherein the AlGaInN thick film internal diameter exceeds 150 μm.
6. The light emitting diode (LED) as claimed in claim 1 , wherein the AlGaInN thick film internal diameter is about 200˜1000 μm.
7. The light emitting diode (LED) as claimed in claim 1 , wherein the bottom shape of AlGaInN thick film comprises a polygon, a circle or an ellipse.
8. The light emitting diode (LED) as claimed in claim 7 , wherein the polygon comprises a quadrangle or a hexagon.
9. The light emitting diode (LED) as claimed in claim 1 , wherein the included angle between AlGaInN thick film bottom and oblique side is about 43˜62°.
10. The light emitting diode (LED) as claimed in claim 1 , wherein the textured top surface comprises a convex structure or a concave structure.
11. The light emitting diode (LED) as claimed in claim 10 , wherein the shape of convex structure or concave structure comprises a polygon, a circle or an ellipse.
12. The light emitting diode (LED) as claimed in claim 10 , wherein the shape size of convex structure or concave structure is smaller than the LED chip size.
13. The light emitting diode (LED) as claimed in claim 12 , wherein the shape size of convex structure or concave structure is about 1 nm˜500 μm.
14. The light emitting diode (LED) as claimed in claim 10 , wherein the convex structure or the concave structure has a sidewall vertical or oblique to its bottom.
15. The light emitting diode (LED) as claimed in claim 10 , wherein the convex structure or the concave structure is a matrix.
16. The light emitting diode (LED) as claimed in claim 15 , wherein the period of matrix is smaller than the LED chip size.
17. The light emitting diode (LED) as claimed in claim 16 , wherein the period is about 1 nm˜500 μm.
18. The light emitting diode (LED) as claimed in claim 10 , wherein the height difference of convex structure or concave structure is less than the AlGaInN thick film thickness.
19. The light emitting diode (LED) as claimed in claim 10 , wherein the height difference of convex structure or concave structure is from 1 nm to the AlGaInN thick film thickness.