LIGHT-EMITTING DEVICE AND MANUFACTURING METHOD THEREOF

1 . A manufacturing method for a light-emitting device, comprising:

forming a semiconductor stack;

forming an electrode on the semiconductor stack, wherein the electrode comprises a first top surface and a side surface;

forming an insulating stack on the semiconductor stack and the electrode, wherein the insulating stack comprises a plurality of first sub-layers with a first refractive index and a plurality of second sub-layers with a second refractive index alternately stacked;

removing a portion of the insulating stack to expose the first top surface, leaving another portion of the insulating stack having a second top surface surrounding the first top surface, and a level of the second top surface is lower than or equal to that of the first upper surface; and

forming an electrode pad on the insulating stack, wherein the electrode pad contacts the first top surface.

2 . The manufacturing method according to claim 1 , further comprising:

forming a sacrificial layer on the insulating stack; and

a portion of the sacrificial layer and the portion of the insulating stack are removed to expose the first top surface.

3 . The manufacturing method according to claim 2 , wherein:

after removing the portion of the sacrificial layer and the portion of the insulating stack, a remaining portion of the sacrificial layer has a third top surface, and a level of the third top surface is lower than or equal to that of the second top surface.

4 . The manufacturing method according to claim 2 , further comprising grinding the sacrificial layer and forming a flat top surface of the sacrificial layer before removing the portion of the sacrificial layer and the portion of the insulating stack.

5 . The manufacturing method according to claim 2 , further comprising removing a remaining portion of the sacrificial layer after exposing the first top surface.

6 . The manufacturing method according to claim 1 , further comprising removing a portion of the semiconductor stack and a portion of the insulating stack to form a plurality of the light-emitting devices.

7 . The manufacturing method according to claim 1 , before forming the electrode further comprising:

forming a protective layer covering the semiconductor stack; and

forming an opening in the protective layer;

wherein the electrode is filled in the opening and electrically connected to the semiconductor stack.

8 . The manufacturing method according to claim 7 , further comprising forming a contact layer on the semiconductor stack, wherein the protective layer covers the contact layer and the opening exposes the contact layer.

9 . The manufacturing method according to claim 1 , wherein a level difference between the first top surface and the second top surface is less than 0.5 μm.

10 . A light-emitting device, comprising:

a semiconductor stack;

an electrode formed on the semiconductor stack, comprising a first top surface and a side surface;

an insulating stack covering the semiconductor stack and the side surface, comprising a plurality of first sub-layers with a first refractive index and a plurality of second sub-layers with a second refractive index alternately stacked; and

an electrode pad formed on the insulating stack, connecting to the first top surface;

wherein the insulating stack comprises a second top surface surrounding the first top surface and having a level lower than or equal to that of the first top surface.

11 . The light-emitting device according to claim 10 , wherein a level difference between the first top surface and the second top surface is less than 0.5 μm.

12 . The light-emitting device according to claim 10 , wherein:

the semiconductor stack comprises a first semiconductor layer and a mesa on the first semiconductor layer, the mesa includes a second semiconductor layer and the first semiconductor layer comprises an exposed region not covered by the mesa;

the electrode is formed on the exposed region and has a thickness greater than a height of the mesa.

13 . The light-emitting device according to claim 10 , wherein:

the semiconductor stack comprises a first semiconductor layer and a mesa on the first semiconductor layer, the mesa comprises a second semiconductor layer and the first semiconductor layer comprises an exposed region not covered by the mesa;

the electrode comprises a first electrode on the exposed region and a second electrode on the mesa, and the thickness of the first electrode is greater than the thickness of the second electrode.

14 . The light-emitting device according to claim 13 , wherein a level difference between a top surface of the first electrode and a top surface of the second electrode is less than 0.5 μm.

15 . The light-emitting device according to claim 10 , further comprising a protective layer covering the semiconductor stack;

wherein the protective layer comprises an opening and the electrode is filled in the opening and electrically connected to the semiconductor stack.

16 . The light-emitting device according to claim 15 , further comprising a contact layer under the protective layer;

wherein the opening is formed on the contact layer and the electrode is connected to the contact layer.

17 . The light-emitting device according to claim 10 , further comprising a covering layer formed on the insulating stack;

wherein the covering layer comprises a third top surface which has a level lower than or equal to that of the second top surface.

18 . The light-emitting device according to claim 10 , wherein the electrode pad is formed on the third top surface.

19 . The light-emitting device according to claim 10 , wherein the electrode pad covers and contacts the second top surface.

20 . The light-emitting device according to claim 10 , wherein each of the first sub-layers and the second sub-layers comprises a cross-section, and the second top surface comprises the cross-sections.