Light emitting diode with a micro-structure lens having a ridged surface

1. A light emitting diode (LED) with a micro-structure lens, comprising:

a LED die;

a phosphor layer disposed over and vertically aligned with the LED die; and

a micro-structure lens disposed over the LED die, the micro-structure lens including:

a convex lens portion; and

at least one concentric ridge structure surrounding the convex lens portion;

wherein a first optical path length from an edge of the LED die to a top center of the micro-structure lens is substantially the same as a second optical path length from the edge of the LED die to a side of the micro-structure lens, and wherein the convex lens portion is wider than the LED die.

2. The LED of claim 1 , wherein the micro-structure lens comprises silicon (Si).

3. The LED of claim 1 , wherein the at least one concentric ridge structure has the same height as the convex lens portion.

4. The LED of claim 1 , wherein the at least one concentric ridge structure has a lower height compared to the convex lens portion.

5. The LED of claim 1 , wherein a first concentric ridge of the at least one concentric ridge structure closer to a center of the micro-structure lens has a higher height than a second concentric ridge of the at least one concentric ridge structure.

6. The LED of claim 1 , wherein the at least one concentric ridge has a circular shape.

7. The LED of claim 1 , wherein the at least one concentric ridge has an oval shape.

8. The LED of claim 1 , further comprising a lens base layer disposed laterally around the LED die, wherein the micro-structure lens is disposed over the lens base layer.

9. The LED of claim 1 , wherein the convex lens portion and the at least one concentric ridge structure collectively make up an entire upper surface of the micro-structure lens.

10. The LED of claim 1 , wherein an entire upper surface of the LED die is covered by the phosphor layer.

11. The LED of claim 1 , further comprising a reflective layer below the LED die disposed on a substrate.

12. The LED of claim 11 , wherein the reflective layer comprises silver (Ag).

13. The LED of claim 11 , further comprising a solder layer disposed over the reflective layer.

14. A light emitting diode (LED) with a micro-structure lens, comprising:

a substrate having a reflective layer;

a LED die disposed over the reflective layer;

a phosphor coating disposed over the LED die, wherein the phosphor coating is vertically aligned with the LED die; and

a micro-structure lens disposed over the LED die, the micro-structure lens including:

a convex lens portion; and

at least one concentric ridge structure surrounding the convex lens portion;

wherein a first optical path length from an edge of the LED die to a top center of the micro-structure lens is substantially the same as a second optical path length from the edge of the LED die to a side of the micro-structure lens, and wherein the convex lens portion has a greater lateral dimension than the LED die.

15. The LED of claim 14 , further comprising a solder layer disposed over the reflective layer.

16. The LED of claim 14 , further comprising a lens base layer disposed laterally around the LED die, wherein the micro-structure lens is disposed over the lens base layer.

17. A light emitting structure, comprising:

a light-emitting diode (LED) die;

a phosphor material disposed over and vertically aligned with the LED die; and

a lens disposed over the LED die, the lens including:

a convex lens surface; and

a concentric ridge structure circumferentially surrounding the convex lens surface in a top view;

wherein the convex lens surface is wider than the LED die, and wherein a side surface of the lens is curved, and wherein a first optical path length from an upper edge of the LED die to the convex lens surface is substantially the same as a second optical path length from a lateral edge of the LED die to the side surface of the lens.

18. The light emitting structure of claim 17 , further comprising:

a lens base layer disposed laterally around the LED die, wherein the lens is disposed over the lens base layer; and

a reflective layer below the LED die disposed on a substrate.

19. The light emitting structure of claim 17 , wherein the concentric ridge structure has at least one of: a pointed peak or a curved peak.

20. The light emitting structure of claim 17 , wherein an entirety of an upper surface of the LED die is covered by the phosphor material.